Lower Extremity Flashcards
A 65-year-old man is referred for evaluation of a 3 x 4-cm wound with exposed tendon over the distal anterior tibia after sustaining fracture to the lateral malleolus, which was successfully treated with cast immobilization. The wound had been managed with local wound care for the past several weeks. Physical examination shows a clean wound with some fibrinous exudate. Periosteum and peritenon are intact. Pulses cannot be palpated. Pencil Doppler signals in dorsalis pedis and posterior tibialis are noted. Which of the following studies is the most appropriate next step in management?
A) Ankle brachial index
B) CT angiography
C) MRA
D) MRI
E) Percutaneous angiography
The correct response is Option A.
This patient has a pressure sore from cast immobilization. He also has asymptomatic peripheral vascular disease, as is evidenced from his clinical examination. For the lower extremity to heal, adequate blood flow is required and this can be most effectively quantified with an ankle brachial index measurement. Ankle brachial index less than or equal to 0.9 establishes the presence of peripheral artery disease. Ankle brachial index between 0.5 and 0.79 yields wound healing issues and less than 0.5 results in rest pain and arterial insufficiency.
CT angiography, MRI, MRA, and percutaneous angiography can assist in delineating anatomy but they do not yield clinically helpful information about perfusion, prognosis, or stratification of peripheral artery disease.
A 65-year-old man is referred for evaluation of a 3 x 4-cm wound with exposed tendon over the distal anterior tibia after sustaining fracture to the lateral malleolus, which was successfully treated with cast immobilization. The wound had been managed with local wound care for the past several weeks. Physical examination shows a clean wound with some fibrinous exudate. Periosteum and peritenon are intact. Pulses cannot be palpated. Pencil Doppler signals in dorsalis pedis and posterior tibialis are noted. Which of the following studies is the most appropriate next step in management?
A) Ankle brachial index
B) CT angiography
C) MRA
D) MRI
E) Percutaneous angiography
The correct response is Option A.
This patient has a pressure sore from cast immobilization. He also has asymptomatic peripheral vascular disease, as is evidenced from his clinical examination. For the lower extremity to heal, adequate blood flow is required and this can be most effectively quantified with an ankle brachial index measurement. Ankle brachial index less than or equal to 0.9 establishes the presence of peripheral artery disease. Ankle brachial index between 0.5 and 0.79 yields wound healing issues and less than 0.5 results in rest pain and arterial insufficiency.
CT angiography, MRI, MRA, and percutaneous angiography can assist in delineating anatomy but they do not yield clinically helpful information about perfusion, prognosis, or stratification of peripheral artery disease.
A 25 year old healthy male has a 5 x 5 cm wound of his weight bearing heel that requires closure. What is the arterial blood supply of the best reconstructive option?
A) Medial plantar artery
B) Medial femoral circumflex
C) Radial artery
D) Peroneal perforators
E) Dorsalis pedis
The correct answer is option a.
Heel wounds are best reconstructed with glabrous tissue if possible. The medial plantar artery is the vascular supply to the medial plantar flap. This flap provides durable glabrous offering the best reconstruction to replace “like tissue with like tissue” Other options for heel reconstruction typically involve free tissue transfer. Some people debate if muscle flaps or fasciocutaneous flaps are better but both have successfully be used. The medial femoral circumflex supplies the gracilis flap and the radial artery supplies the radial forearm flap. Peroneal perforators supply the reverse sural flap. Depending on the size and exact location all of these flaps are potential options but likely secondary choices if a medial plantar flap is available. Dorsalis pedis flaps have a high donor site morbidity and would not reach the heel. 
A 56-year-old man who is an active smoker sustains a degloving injury of the left foot from a motorcycle collision. The heel was avulsed from the calcaneus by a deep posterior laceration but has normal capillary refill. No tissue is missing, but the wound is heavily contaminated and the calcaneus has an abrasion that is imbedded with grit. After irrigation and debridement in the operating room, which of the following is the most appropriate next step in management of this wound?
A) Coverage with a free gracilis muscle flap
B) Healing by secondary intention
C) Layered closure over a drain
D) Negative pressure wound therapy and skin grafting
E) Serial debridement and delayed closure
The correct response is Option E.
The most appropriate management of this wound is serial debridement and delayed closure. With such a high level of contamination of both the soft and hard tissues, layered closure after the initial debridement will very likely lead to infection, especially in a patient with a history of smoking. It would be a mistake to perform a free tissue transfer in a highly contaminated wound. Furthermore, there is no missing or ischemic tissue. Negative pressure wound therapy followed by skin grafting would not be appropriate for a deep wound with bone exposure when local tissues are available for closure; this would be more appropriate for a superficial wound with missing skin. Healing by secondary intention is an option; however, serial debridement and delayed closure will take less time, is less painful, and avoids scar formation in the heel.
You are evaluating a 50-year-old male has non-healing foot ulcer in distal toe. Angiogram shows normal SFA with long segment occlusion of popliteal artery with reconstitution of the anterior tibial artery and run off of dorsalis pedis. Patient has previously had bilateral saphenous vein stripping. The most appropriate next step is:
A) Popliteal-distal bypass using PTFE
B) Popliteal- distal bypass using lesser saphenous vein
C) Toe amputation
D) Below knee amputation
The correct answer is option B.
The patency rate of autogenous vein grafts for infra-popliteal bypasses is superior to that of prosthetic grafts. However prosthetic grafts may be used in limb salvage situations, as an alternative to amputation. Vein stripping (for patients with varicose veins) typically involves removal of the great saphenous vein. In such cases, alternate autologous options include the lesser saphenous, superficial femoral, basilic, or cephalic veins.
A 26-year-old man comes to the office for evaluation after sustaining an open injury to the right knee during a motorcycle collision 2 weeks ago. Physical examination shows a 2-cm defect over the patella. A medial gastrocnemius flap is planned to close the defect. Which of the following is the dominant vascular supply to this muscle?
A) Anterior tibial
B) Inferior geniculate
C) Medial sural
D) Posterior tibial
E) Superior geniculate
The correct response is Option C.
The gastrocnemius flap is the primary flap used to cover soft-tissue defects of the upper third of the tibia and knee. The gastrocnemius muscle is a bipennate muscle located on the posterior surface of the lower leg. The muscle originates from the medial and lateral condyles of the femur and inserts into the Achilles tendon. The dominant blood supply of the muscle is the medial and lateral sural arteries, which are branches of the popliteal artery. Generally only one head of the gastrocnemius flap is harvested to cover soft-tissue defects. The muscle alone is generally taken and is covered with a split-thickness skin graft for lower extremity reconstructions. The geniculate arteries primarily supply the bone around the knee joint.
A 40-year-old man undergoes open reduction and internal fixation of an open fracture of the ankle. Debridement of nonviable tissue results in the exposure of the lateral joint and hardware. Coverage of the lateral malleolus with the flap shown is planned. Which of the following arteries must be intact for this flap to be viable?
A ) Anterior tibial
B ) Dorsalis pedis
C ) Lateral genicular
D ) Lateral plantar
E ) Peroneal
The correct response is Option E.
The reverse-flow sural flap has become one of the more dependable solutions in distal third leg wound and heel reconstruction. Survival of the flap depends on intact flow into the superficial
sural arterial network via perforators from the peroneal system. The largest perforator arises roughly 5 cm cephalad to the lateral malleolus and typically marks the lowest pivot point for the flap.
None of the remaining choices would provide adequate perfusion for this flap.
Which lower leg compartment is most prone to compartment syndrome:
A) Lateral
B) Anterior
C) Deep Posterior
D) Superficial posterior
The correct answer is option B.
The anterior compartment is the most commonly affected compartment, usually secondary to tibial fracture. It contains the anterior tibial artery, deep peroneal nerve, tibialis anterior muscle, peroneus tertius, extensor hallucis longus, and extensor digitorum longus.
A 1-year-old boy is scheduled to undergo primary surgical reconstruction of congenital talipes equinovarus. Subsequent skin shortage and wound complications are best prevented by which of the following methods?
A ) Free fasciocutaneous flap transfer
B ) Healing via second intention
C ) Preoperative tissue expansion
D ) Split-thickness skin grafting
E ) Two-stage local flap delay and transfer
The correct response is Option C.
Although the treatment of congenital talipes equinovarus (CTEV) has trended toward conservative routines of manipulation and limited surgical release (eg, Ponseti technique), surgical treatment of CTEV may be necessary in cases of delayed treatment or failure of the conservative regime. Surgical correction may be attempted via a gradual technique (Ilizarov) or as an acute correction with release of the contracted posterior and medial elements.
Many acute surgical CTEV corrections can be accomplished without skin or wound difficulties; when such difficulties are anticipated, preoperative placement of tissue expanders has proven useful in allowing primary closure of the release sites with minimal morbidity.
Second intention healing and split-thickness skin grafting may not be appropriate depending on the purposeful injury and potential exposure of tendons during the contracture release.
Adjacent tissue transfer may be compromised by altered local anatomy, and creation of a second wound around the ankle by the donor site may threaten future surgical approaches for additional correction of the deformity.
Free tissue transfer may be warranted in late correction cases with severe tissue shortage but rarely would be necessary in the setting of primary correction.
A 52-year-old man is brought to the emergency department after sustaining a gunshot wound to the right forearm. History includes well-controlled diabetes mellitus type 2, coronary artery disease, and renal insufficiency. Examination of the forearm shows viable muscle coverage and gross instability. A radiograph is shown. Following debridement and stabilization of the wound, reconstruction of the defect is planned via a vascularized free fibular transfer. In addition to clinical examination, which of the following is the most appropriate preoperative evaluation of this patient €™s lower extremity?
A ) Ankle brachial indices
B ) Color-flow Doppler imaging
C ) CT angiography
D ) Traditional angiography
E ) Transcutaneous partial pressure of oxygen
The correct response is Option B.
While anatomic variants in the vasculature of the leg are rare, failure to recognize these prior to sacrifice of the peroneal artery during harvest of a fibular free flap can result in disastrous ischemic complications. Variations occur more commonly in patients who have vascular insufficiency due to underlying atherosclerotic changes. In these patients, clinical examination alone is insufficient to adequately define blood flow patterns to the leg and foot.
Color-flow Doppler imaging has demonstrated excellent ability to define the presence of flow-limiting lesions in the leg. Monophasic signals in any of the three major runoff vessels strongly suggest that the limb will be at risk for ischemia following sacrifice of the peroneal artery. Comparison of the findings on color-flow Doppler with angiography demonstrates that angiography is an unnecessary addition to the initial study.
Angiography and CT angiography offer excellent road maps of the vasculature of the lower extremity, but each does involve the use of intravenous contrast. The dose of contrast used in CT angiography is significantly lower than that in traditional angiography, but neither would be justified in this patient with pre-existing renal insufficiency.
MR angiography provides a map of the vessels comparable to both angiography and CT angiography without the use of nephrotoxic contrast agents. The additional information gained by seeing the vessels preoperatively (by MRA, CT angiography, or traditional angiography) may be justified when very long segments of the bone need to be harvested or when the perfusion to the overlying skin paddle may be better defined.
Transcutaneous partial pressure of oxygen measures perfusion and does not offer any anatomic detail.
The postoperative image shown demonstrates the free fibula reconstruction of the radius.
A 28-year-old man presents 8 days after open reduction and internal fixation of an unstable distal tibia fracture. Postoperatively, the incision has dehisced. Examination shows a 5 × 2-cm open wound with marginal skin necrosis and exposed hardware. Which of the following is the most appropriate next step in soft-tissue coverage?
A) Debridement with application of skin substitute
B) Hardware removal, casting, and wound care
C) Hyperbaric oxygen and wound care
D) Operative debridement and placement of a VAC for a bridge to skin grafting
E) Operative debridement and vascularized reconstruction with a flap
The correct response is Option E.
The best treatment that would allow salvage of the fracture fixation is operative debridement and vascularized flap reconstruction. Stable fixation has been achieved and subacute wound dehiscence has occurred because of ischemia or devitalization of the overlying soft tissue. This is due to the forces of the original trauma as well as potential further traumatic insult of the tissue during surgical repair. In the absence of infection, immediate soft-tissue reconstruction will provide stable vascularized soft-tissue coverage of the fracture site and the hardware. As such, vascularized flap reconstruction is appropriate. In the distal leg, this often requires free tissue transfer, but depending on the location and size of the defect, soleus flap or perforator propeller flaps can be used.
Gustilo provided a classification of open fractures of the leg in which the fracture site was exposed through a disruption of soft-tissue integrity:
Determination of the type of flap reconstruction required requires assessment of not only the location and size of the defect, but also the zone of injury. Greater degrees of force are associated with the increasing Gustilo classification such that type III fractures often require free tissue transfer because of concomitant damage of the regional and local tissues.
Operative debridement and placement of a VAC for a bridge to skin grafting is a potential treatment for an open wound with exposed bone without hardware. The period of time in which the wound remains open and granulates during this process provides a very high risk for hardware infection, nonunion, and osteomyelitis.
Debridement with skin advancement and closure is likely to fail because of the difficulty in providing appropriate tension-free advancement flaps in the leg, combined with the need to accommodate for tissue loss from the debridement and ischemia of the advancing skin edges. The reliability of this treatment is poor and would have high risk for failure and subsequent hardware infection and nonunion or osteomyelitis.
Hardware removal, casting, and wound care is not indicated since the fracture repair is intact and no signs of infection are present. However, if hardware removal were required because of overt infection, the most appropriate treatment would be placement of an external fixator and soft-tissue flap reconstruction.
Hyperbaric oxygen and wound care is not the best option in this acute situation in which prompt soft-tissue reconstruction and vascularized coverage of the fracture site are required to salvage the existent fixation and avoid mal/nonunion or osteomyelitis.
A 25-year-old construction worker has a 4-cm-diameter posterior calcaneal ulcer with exposed bone on removal of a short-leg cast applied 6 weeks ago for an ankle fracture. Coverage with a lateral calcaneal artery flap is planned. The lateral calcaneal artery is usually the terminal branch of which of the following arteries?
A) Anterior tibial
B) Dorsalis pedis
C) Lateral malleolar
D) Peroneal
The correct response is Option D.
Anatomic dissections by Drs. Grabb and Argenta found that the lateral calcaneal artery is usually the terminal branch of the peroneal artery but occasionally may arise from the posterior tibial artery. The branches of the peroneal include the nutrient artery which supplies the fibula, the perforating branch which gives branches to the tarsus, the communicating branch and the lateral calcaneal.
A 50-year-old man has noninfected wound dehiscence with exposure of the hardware two weeks after undergoing open reduction and internal fixation of an ankle fracture. A photograph and radiograph are shown above. Following debridement of the wound, which of the following is the most appropriate management?
A) Skin grafting
B) Coverage with a free flap
C) Application of an external fixator and skin grafting
D) Removal of the hardware and skin grafting
E) Removal of the hardware and coverage with a free flap
The correct answer is option B.
This patient has early wound dehiscence after undergoing open reduction and internal fixation of a lateral malleolus fracture. Appropriate management involves early coverage of the exposed bone and hardware to promote bony union while preventing bacterial colonization of the hardware, which may lead to the development of osteomyelitis. Because this patient underwent open reduction and internal fixation only two weeks ago, fixation is still required to maintain rigid fracture stabilization. Instead, coverage with a free flap is recommended to provide stability and vascularity and to enhance function once bony union is obtained.
Skin grafting will not provide stable, well vascularized coverage in this patient. External fixation is problematic because of the location of the fracture. Removal of the hardware two weeks after fracture is indicated only for established hardware failure.
Where can the blood supply of medial plantar artery flap be located?
A) Between the abductor hallucis and flexor digitorum brevis
B) Between the adductor hallucis and flexor hallucis brevis
C) Between the adductor hallucis and flexor digiti minimi brevis
D) Between the lumbricals
Correct answer is option a.
The medial plantar artery is typically identified between the abductor hallucis and the flexor digitorum brevis.
Scaglioni 2018 correct answer is option a.
A 65-year-old woman with a history of peripheral vascular disease presents with a complex soft tissue defect over her distal tibia following trauma. The wound is 8 cm × 6 cm, with exposed bone and periosteal stripping. CT angiography reveals adequate vascular supply to the limb but no significant perforating vessels near the defect. What is the most reliable option for soft tissue coverage while minimizing donor site morbidity?
A) Anterolateral thigh fasciocutaneous free flap
B) Local gastrocnemius flap
C) Rectus abdominis myocutaneous flap
D) Propeller flap based off the anterior tibial artery
E) Split-thickness skin graft
The correct answer is A) Anterolateral thigh fasciocutaneous free flap
Explanation:
The anterolateral thigh (ALT) fasciocutaneous free flap is a reliable and versatile option for coverage of lower extremity defects. It provides robust vascularized coverage with minimal donor site morbidity, as it does not require harvesting muscle. For defects involving exposed bone and periosteal stripping, split-thickness skin grafts are unreliable.
Rationale for other options:
• B) Local gastrocnemius flap: This flap cannot reach defects in the distal third of the tibia or near the ankle.
• C) Rectus abdominis myocutaneous flap: Although effective, it involves sacrificing a muscle, leading to higher donor site morbidity compared to the ALT flap.
• D) Propeller flap based off the anterior tibial artery: This option is not viable in this case due to the lack of a significant perforating vessel as identified on CT angiography.
• E) Split-thickness skin graft: This is not suitable for defects with exposed bone or periosteal stripping, as it requires a vascularized wound bed for survival.
Key considerations for flap selection:
Microsurgical techniques are feasible in elderly patients with peripheral vascular disease and provide optimal outcomes for complex wounds. ALT fasciocutaneous flaps are associated with excellent coverage, aesthetic outcomes, and minimal donor site morbidity.
References:
1. Gohritz A, Osinga R, Haumer A, Schaefer DJ. Microsurgical reconstruction of the lower extremity in the elderly. Clin Plast Surg. 2021;48(2):331-340. doi:10.1016/j.cps.2021.01.008
2. Üstün GG, Aksu AE, Uzun H, Bitik O. The systematic review and meta-analysis of free flap safety in elderly patients. Microsurgery. 2017;37(5):442-450. doi:10.1002/micr.30156
3. Yang Z, Xu C, Zhu Y, et al. Flow-through free anterolateral thigh flap in reconstruction of severe limb injury. Ann Plast Surg. 2020;84(5S Suppl 3):S165-S170. doi:10.1097/SAP.0000000000002372
A 21-year-old man undergoes reconstruction with a free flap. Photographs are shown. This procedure places the patient at risk for claw toe with loss of active flexion of the great toe. The muscle responsible for this functional loss is located in which of the following compartments in the lower leg?
A) Anterior
B) Deep posterior
C) Lateral
D) Superficial posterior
The correct response is Option B.
Claw toe or loss of active flexion of the great toe interphalangeal joint can result from harvest of the flexor hallucis longus for free fibula flaps. The flexor hallucis longus is present within the deep posterior compartment of the lower leg and should be resuspended to the interosseus membrane and posterior tibial muscles as needed to maintain proper tension. Physical therapy is initiated after adequate wound healing to maintain the mobility of the great toe and ankle. The deep posterior compartment musculature is composed of the tibialis posterior, the flexor digitorum longus, the flexor hallucis longus, and the popliteus.
The superficial posterior compartment musculature is composed of the gastrocnemius, soleus, and plantaris.
The anterior compartment musculature is composed of the tibialis anterior, the extensor digitorum longus, extensor hallucis longus, and the peroneus tertius.
The lateral compartment musculature is composed of the peroneus longus and brevis muscles.
A 50-year-old man comes to the office because of a persistent nonhealing wound 6 months after he underwent open reduction and internal fixation of an open ankle fracture. Examination shows palpable pedal pulse with retained protective sensation of the foot. Which of the following is the most appropriate initial step in management of this patient?
A) Application of collagenase ointment
B) Core needle bone culture
C) Coverage with a free flap
D) Operative debridement
E) Referral for hyperbaric oxygen therapy
The correct response is Option D.
The patient is at high risk for fracture nonunion and osteomyelitis. The best next course of management is operative debridement ideally along with the treating orthopedist to make judgments about bone viability and debridement and the risks and benefits of hardware removal. Enzymatic wound debridement would not address the concerns about the deeper wound issues. The role for hyperbaric oxygen in the scenario presented is not well established. Bone cultures at the time of operative debridement should be obtained; but, percutaneous core needle cultures alone would not likely be adequate to obtain best healing. Free flap coverage may be required but is not indicated at this time.
Which of the following conditions is a relative CONTRAINDICATION for use of the flap in the image shown for reconstruction of an 8 x 10-cm anterior ankle wound?
A) Diabetes mellitus
B) Hypertension
C) Joint exposure with loss of the joint capsule
D) Occlusion of the peroneal artery
E) Underlying osteomyelitis
The correct response is Option D.
Hypertension does not preclude the use of any fasciocutaneous flaps in the lower extremity.
Diabetes mellitus can be associated with peripheral vascular disease, but by itself, would not prevent successful use of the reverse sural artery flap for foot or ankle reconstruction. Appropriate preoperative workup would include noninvasive ultrasound study of the lower extremity vasculature to prove the peroneal artery was patent.
Vascularized flaps, including the reverse sural artery flap, provide excellent coverage for foot/ankle wounds, including those with underlying osteomyelitis. Effective treatment would necessitate adequate debridement and antibiotic therapy as part of the reconstructive paradigm.
The distally based sural artery flap receives its blood supply from a few sources, the most robust of which are perforators from the peroneal artery. The most distal of these perforators arise between 4 and 7 cm proximal to the lateral malleolus. Additional perfusion arises from neurocutaneous perforators from the sural nerve and venocutaneous perforators from the lesser saphenous vein.
A 17-year-old boy sustains a traumatic injury to the right lower extremity. Examination shows weakness of plantar flexion and loss of sensation over the plantar surface of the foot. Which of the following nerves is most likely injured?
A ) Deep peroneal
B ) Femoral
C ) Obturator
D ) Superficial peroneal
E ) Tibial
The correct response is Option E.
The most likely nerve to be injured is the tibial nerve.
The tibial nerve is a branch of the sciatic nerve. It travels through the popliteal fossa and gives off branches to the gastrocnemius, soleus, plantaris, and popliteus muscles. The tibial nerve travels in proximity to the posterior tibial artery. In the leg, it gives off branches to the flexor digitorum longus, tibialis posterior, and flexor hallucis longus. Distally in the foot, it branches to give rise to the medial and lateral plantar nerves, which provide sensation to the plantar surface of the foot. Injury to the tibial nerve results in deficits of plantar flexion, as well as anesthesia to the plantar surface of the foot. Tibial nerve disruption has been considered an indication for amputation as opposed to limb salvage in traumatic injuries of the lower extremity. However, one study suggests that limb salvage can be performed even in the face of absent plantar sensation at the time of presentation. This may indicate that absence of plantar sensation is not a reliable correlate for tibial nerve disruption.
The deep peroneal nerve arises from the common peroneal nerve at the fibular neck. It travels in the anterior compartment of the leg and gives branches to the tibialis anterior, extensor hallucis longus, and extensor digitorum longus and brevis, as well as peroneus tertius. The sensory distribution is in the area of the first web space. Injury to the deep peroneal nerve causes weakness in dorsiflexion of the foot.
The femoral nerve innervates muscles of the anterior thigh, including the quadriceps group, iliacus, and sartorius. Injury to the femoral nerve results in weakness of leg extension.
The superficial peroneal nerve arises from the common peroneal nerve at the fibular neck. It supplies the lateral compartment of the leg, giving motor branches to peroneus longus and brevis, as well as sensory contribution to the lateral aspect of the leg. Injury to the superficial peroneal nerve results in anesthesia of the lateral aspect of the leg and weakness in eversion and plantar flexion of the foot.
The obturator nerve provides innervation to the medial thigh muscles (adductor group), including adductor brevis, longus, and magnus, as well as the gracilis and obturator externus. The cutaneous branch provides sensation of the medial thigh. Injury to the obturator nerve results in weakness in thigh adduction and sensory deficits in the medial thigh.
A 12-year-old boy is referred to a multidisciplinary sarcoma treatment center because of a deep localized rhabdomyosarcoma of the right thigh. After neoadjuvant radiotherapy, radical resection with curative intent, including a 20-cm segmental intercalary resection of involved distal femoral diaphysis, is performed. Skin and major neurovascular structures will be spared. Postoperative chemotherapy is planned. Which of the following is the most appropriate method for management of the bony defect in this patient?
A) Distraction osteogenesis
B) Free fibula transfer with femoral allograft (Capanna technique)
C) Induced membrane (Masquelet) technique
D) Lower extremity rotationplasty (Van Ness procedure)
E) Pedicled medial femoral condyle flap
The correct response is Option B.
Rhabdomyosarcomas represent the most common soft-tissue sarcoma of childhood and are responsible for approximately half of all soft-tissue sarcomas in this age group. They are thought to originate from immature cells that are destined to form striated skeletal muscle, although they can arise anywhere in the body. With modern multimodal management, the cure rates for localized disease are generally greater than 70% overall. The primary goal of local tumor control in extremity rhabdomyosarcoma is limb-sparing complete resection where possible.
Vascularized bone grafting represents the gold standard for reconstructing segmental bone loss greater than 6 cm associated with a compromised local soft-tissue environment that occurs with radiotherapy and chemotherapy. For large weight-bearing intercalary reconstruction, significant literature supports the combination of a large structural allograft combined with vascularized fibula as described by Capanna in 1980. With this combination, the neoosteogenic properties of the free fibula are supplemented by the immediate structural support of the bulk allograft and provide a durable single-stage biological reconstruction.
Distraction osteogenesis is a technique of de novo bone formation that capitalizes on normal bone healing with gradual, surgically controlled distraction of adjacent osteotomy defects and has the advantage of simultaneously expanding surrounding soft-tissue envelopes. The technique requires viable bone in proximity to one another following a latency phase and is useful in limb lengthening and craniofacial procedures but has limited utility in long segmental tumor reconstruction.
The induced membrane technique proposed by Masquelet is a two-step procedure where a segment of bone loss is first filled with an acrylic spacer and later replaced by cancellous bone graft in the so-called self-induced reactive “periosteal” membrane. The technique requires two stages and is less favored in the setting of planned radiation or chemotherapy where experience has shown that vascularized flaps or supplemented vascularized allografts are beneficial. The medial femoral condyle flap has been used for small osteoperiosteal, corticoperiosteal, and osteocartilaginous flaps based off either the articular descending genicular or superomedial genicular arteries. It would be insufficient in size for a 20-cm-long bone defect.
The Van Ness rotationplasty is a type of autograft where functional limb below the knee is used to reconstruct more proximal defects. It can be a useful “spare part” reconstructive option in composite proximal extremity resections by repurposing a functional ankle joint more proximally in a rotated configuration for preserved gait advantage at the repurposed knee. A rotationplasty would not be indicated for intercalary resections sparing joint and metaphysis.
A 51-year-old man presents for evaluation of nerve injury following varicose vein stripping of the left leg. Which of the following findings would be expected with saphenous nerve injury in this patient?
A) Anesthesia around the left medial malleolus
B) Hypersensitivity along the dorsum of the left foot
C) Inability to dorsiflex the left foot
D) Increased insertional activity in the tibialis anterior muscle
E) Numbness near the left lateral heel
The correct response is Option A.
Nerve injury is a relatively rare but significant complication of varicose vein stripping. Knowledge of anatomy can help identify which nerve is involved in most injuries. Injury to the saphenous nerve would cause anesthesia over the medial calf and medial malleolus. Injury to the deep peroneal nerve would cause weakness in dorsiflexion and would result in increased insertional activity on electromyography of the tibialis anterior. Hypersensitivity on the dorsal foot or numbness over the lateral heel would come from an injury to the superficial peroneal nerve and the sural nerve, respectively.
A 20-year-old man presents to the emergency department 6 hours after a bicycle accident with an open tibial fracture. The patient was traveling at 10 miles per hour at the time of the accident. The wound is 5 cm in length, and there is moderate contamination. The fracture is a mid-shaft tibial fracture with moderate comminution, with an associated closed fibula fracture. Which of the following Gustilo classifications is most appropriate for this injury?
A) I
B) II
C) IIIA
D) IIIB
E) IIIC
The correct response is Option B.
Though it was never designed to predict treatment, the Gustilo classification has stood the test of time as a highly utilized grading system for lower extremity trauma. It is often used to predict the need for flap coverage, to estimate the risk for osteomyelitis, and to guide antibiotic use.
A 35-year-old man is brought to the emergency department because of an injury to the left lower leg after being involved in a motorcycle collision. X-ray studies confirm a Gustilo IIIB tibia-fibula fracture. After debridement, there is a bone defect measuring 12 cm in the mid shaft of the tibia. Which of the following is the most appropriate technique to restore the bone defect?
A) Autogenous bone grafting
B) Cadaveric bone grafting
C) Coverage with a fibular free flap
D) Osteodistraction
The correct response is Option C.
Although various techniques have been used successfully to reconstruct large bony defects of the lower extremity, the most reliable technique for such a large bone gap is the fibular free flap reconstruction. The Ilizarov osteodistraction technique can be used for large defects, but would necessitate a very long period of immobilization and fixation. Neither autogenous nor cadaveric bone graft would be as reliable as vascularized bone.
A 34-year-old woman presents with a 1-year history of progressive ankle and dorsal foot pain and paresthesias in the first dorsal web space. Electrodiagnostic study is significant for changes in the extensor digitorum brevis muscle. Which of the following nerves is the most likely source of this patient’s symptoms?
A) Deep peroneal
B) Saphenous
C) Superficial peroneal
D) Sural
E) Tibial
The correct response is Option A.
Anterior tarsal tunnel syndrome, also known as deep peroneal nerve (DPN) entrapment, is the result of compression of the DPN at the superior border of the inferior extensor retinaculum at the ankle joint and beneath the extensor hallucis longus tendon. Entrapment can occur as a result of wearing tight-fitting shoes or boots. It is important to rule out exertional anterior compartment syndrome or common peroneal nerve entrapment as the cause of symptoms. The nerve can also experience traction injury caused by chronic ankle instability due to ankle sprains.
The DPN travels in the leg between the extensor digitorum longus (EDL) and tibialis anterior and distally between the EDL and extensor hallucis longus just proximal to the ankle before dividing into the lateral and medial branches, 1.3 cm proximal to the ankle joint. The lateral branch innervates the extensor digitorum brevis (EDB) and the tarsometatarsal (TMT) and metatarsophalangeal joints. The medial branch, a sensory branch, travels to the first dorsal web space and has a dorsomedial cutaneous branch to the second toe and a dorsolateral cutaneous branch to the great toe. Entrapment of the medial branch can occur from the extensor hallucis brevis (EHB) tendon, as it travels over the nerve at the first and second TMT joints. Patients typically present with pain along the dorsum of the foot with intermittent numbness radiating to the first dorsal web space. A Tinel sign may be elicited over the superior and inferior retinaculum along the DPN, resulting in tingling over the first dorsal web space of the foot. The EDB can be weak or atrophied. Patients may also report aching and tightness along the ankle joint or numbness at the first dorsal web space when the ankle is placed in plantar flexion with the toe extended. Electrodiagnostics should be ordered to confirm the diagnosis and location of the entrapment.
Regarding surgical treatment of osteomyelitis of the lower extremity, which of the following is most important?
A) Muscle rather than fasciocutaneous flap coverage
B) Fasciocutaneous rather than muscle flap coverage
C) Adequate debridement
D) Irrigation
The correct answer is option C.
While historical studies showed muscle flaps had superior vascularity and better ability to decrease bacterial counts in wounds, these were compared to random pattern fasciocutaneous flaps, not free flaps with a known blood supply. More recent series have shown no difference in clearance of chronic osteomyelitis when comparing muscle and fasciocutaneous flaps. Thorough debridement is believed to be the most critical factor in treatment of osteomyelitis.
Salgado 2005, Kovar 2019, Buono 2018 The correct answer is option C.
What is the blood supply to the anterolateral thigh free flap?
A) Perforators of the ascending branch of the lateral circumflex femoral artery
B) Perforators of the descending branch of lateral circumflex femoral artery
C) Perforators of the medial femoral circumflex artery
D) Saphenous artery
Correct answer is option B.
The anterolateral thigh free flap is supplied by perforators of the descending branch of the lateral circumflex femoral artery. The tensor fascia lata flap is supplied by the ascending, transverse, and descending branches. The gracilis flap is supplied by the medial circumflex femoral artery. The saphenous and medial condylar flaps are supplied by the saphenous artery.
Ali 2009.
An 18-year-old woman comes to the office because of a large osteosarcoma of the distal shaft of the right femur. A 15-cm bone resection is planned, with a resulting large intercalary segmental defect. The overlying skin and soft-tissue is not involved. The patient is very motivated to proceed with limb preservation. Which of the following is the most appropriate option for reconstruction of this defect?
A) Bone allograft
B) Contralateral vascularized fibula free flap
C) Contralateral vascularized fibula free flap with bone allograft
D) Ilizarov bone transportation
E) Ipsilateral pedicled vascularized fibula flap
The correct response is Option C.
In a young patient who desires limb preservation after sarcoma resection, a contralateral vascularized fibula free flap with bone allograft (Capanna technique) is the most appropriate option for a large intercalary segmental defect. This involves placing the fibula flap within an allograft construct and bridging both osteotomy sites. There are advantages to using the allograft with the fibula flap, as a fibula flap alone may have difficulty with weight-bearing and potential fracture. In select cases a double barrel configuration can be used; however, in this patient the defect is too large. An ipsilateral pedicled flap would have difficulty reaching this large defect and would still have issues with fractures from weight-bearing. Ilizarov bone transportation can be performed for smaller defects (4 to 6 cm), but not in a defect this large. Finally, bone allograft alone is an option; however, this has a high rate of nonunion (34% versus 8 to 10%).
A 61-year-old man comes to the office for evaluation of a 3 x 3-cm calcaneal defect with exposed bone. Medial plantar flap reconstruction is planned. The principal blood supply to this flap arises from which of the following arteries?
A) Arcuate
B) Dorsalis pedis
C) Peroneal
D) Plantar arch
E) Posterior tibial
The correct response is Option E.
The primary blood supply to the medial plantar flap is the medial plantar artery, a terminal branch of the posterior tibial artery. The dorsalis pedis is the continuation of the anterior tibial artery and does not contribute to this flap. The peroneal artery is a proximal branch of the posterior tibial artery and descends in the deep posterior compartment posterior to the tibialis posterior and anterior to the flexor hallucis longus; it does not contribute to this flap. The arcuate artery is the terminal branch of the anterior tibial artery. The plantar arch runs on the plantar aspect of the foot at the level of the metatarsals; it is formed from a confluence of the lateral plantar artery and the deep plantar artery from the dorsalis pedis.
True or false: the time to primary bone union is faster in patients with muscle flap coverage compared to fasciocutaneous flap coverage?
A) TRUE
B) FALSE
The correct answer is option B.
There is no difference in time to primary bone union or incidence of tibial non-union when comparing fasciocutaneous and muscle flaps. There is also no difference in time until return to ambulation and full weight bearing.
Yazar 2006, Spfiadellis 2012, Paro 2016, Cho 2017 The correct answer is option B.
A 53-year-old man with a comminuted fracture of the midtibia has a 4 H 3-cm defect of the midanterior surface of the leg at the level of the fracture. He currently smokes two packs of cigarettes daily. Physical examination shows no palpable dorsalis pedis pulse. Which of the following surgical interventions is the most appropriate method of reconstruction in this patient?
(A) Anterior tibialis muscle flap
(B) Below-knee amputation
(C) Gastrocnemius muscle flap
(D) Gracilis free tissue transfer
(E) Soleus muscle flap
The correct response is Option E.
The soleus muscle flap is most appropriate for reconstruction in this patient. The soleus is a bipenniform muscle; its medial head originates from the posterior tibia, and the lateral head originates from the proximal fibula. It is located deep to the gastrocnemius in the superficial posterior compartment. Blood to the medial head is predominantly supplied by the popliteal and posterior tibial arteries and the lateral head is predominantly supplied by the peroneal artery. Depending on the size of the defect, a hemisoleus muscle flap can be used to preserve flexor function.
Below-knee amputation is an option if salvage of the leg is not possible or if the extremity is insensate, particularly in older patients.
An anterior tibialis muscle flap can be used for small defects. In this patient with an absent dorsalis pedis pulse and possible injury to the anterior tibial artery, this is not an optimum choice.
For lower-extremity reconstruction, the gastrocnemius muscle flap is used for knee wounds and proximal tibial defects, the soleus for middle third defects, and free tissue transfer for distal third defects. The gastrocnemius muscle flap might not reach the defect in the middle third and therefore is not the best option. Free tissue transfer is often used for reconstruction of high-velocity injuries to avoid the use of muscle in the zone of injury. Free tissue transfer, however, is not the best option for this 53-year-old man because his history of cigarette smoking and absent pedal pulse suggest the possibility of peripheral vascular disease.
A 70-year-old man undergoes open reduction and internal fixation of an open fracture of the ankle. Debridement of nonviable tissue results in the exposure of the joint and hardware. Coverage with a reverse sural artery flap is planned. A photograph is shown. Which of the following is the most likely adverse outcome associated with the use of this flap?
A) Infection
B) Insufficient bulk
C) Insufficient flap coverage
D) Partial flap loss
E) Wound dehiscence
The correct response is Option D.
The utility of the flap has been proven in both healthy and compromised wounds; neither peripheral arterial disease nor diabetes has precluded its success. Of the possible complications, partial flap loss has occurred most commonly. As a result, numerous modifications to the flap have been proposed. These include maintaining a narrow (2 cm wide) pedicle, including a cutaneous ?tail? along the length of the pedicle and maintaining a mesentery between the sural nerve and the deep fascia.
Infection rates have been low, ranging from 0 to 2.5%. The fasciocutaneous variety of the reverse sural flap is often malleable enough to conform to most defects. When a deeper defect exists, a fasciomusculocutaneous variation of the flap has been designed to carry a portion of the gastrocnemius muscle via one of the larger proximal perforators typically found deep to the cutaneous paddle in the proximal leg.
Cutaneous paddles have been harvested with dimensions of up to 12 × 15 cm, allowing coverage of most ankle and heel wounds.
Reconstruction of larger donor defects with split-thickness skin grafts makes dehiscence unlikely.
A 24-year-old man is brought to the emergency department 2 hours after sustaining injuries to the left lower extremity when he was hit by a motor vehicle. Physical examination shows avulsion of the soft tissue of the posterior thigh. A fracture of the femur is stabilized by an intramedullary rod; the sciatic nerve is noted to be intact but ecchymotic at the level of the mid posterior thigh. Soft tissue is available for coverage. Which of the following is the most appropriate management?
A) Acute resection of the ecchymotic nerve and repair with a nerve graft
B) Delayed resection of the ecchymotic nerve at 10 days and repair with a nerve graft
C) Electromyography after 3 weeks and repair with a nerve graft if fibrillations occur
D) Serial electrodiagnostic studies after 3 weeks and again after 3 months with repair if no improvement
The correct response is Option D.
In cases in which the nerve has undergone a significant crush component, it is important to get a sense of nerve viability and recovery. The nerve conduction study at 3 weeks largely serves as a baseline study as it rarely provides more information than physical examination other than the presence of fibrillations, which indicates at least some axonal loss. The nerve conduction study at 3 weeks is not a reliable indicator of possible nerve recovery; therefore, resection and reconstruction are not advisable at this time point. The 3-month nerve conduction study is able to pick up subtle signs of recovery that may not be evident on physical examination. If at the 3-month mark there are no signs of recovery on physical examination or nerve conduction study, repair is indicated. Acute resection of a possibly viable nerve is not indicated. If the nerve were noted to be transected at the time of initial exploratory surgery, the viability of the nerve ends would not be stable until 7 to 10 days post trauma, making this a good time for definitive repair. In the scenario described, the nerve is in continuity and viability cannot be ascertained intraoperatively at 10 days; therefore, resection and reconstruction are not indicated.
A 40-year-old man is diagnosed with a posterior thigh sarcoma. He undergoes resection of the tumor as well as some of the surrounding muscle. Partial sacrifice of the sciatic nerve is required, leaving a 40% circumferential defect and an 11-cm gap between proximal and distal ends. A photograph is shown. Which of the following is the most appropriate method of nerve reconstruction?
A) Mobilization and primary coaptation
B) Polyglycolic acid nerve tube
C) Processed human allograft conduit
D) Saphenous vein graft
E) Sural nerve cable graft
The correct response is Option E.
Fundamentals of nerve repair include coaptation in a tension-free manner. If there is any tension, nerve grafts or conduits are indicated. In this clinical scenario, there is a large nerve gap that precludes tension-free primary coaptation, even with extensive proximal and distal mobilization. Therefore, a nerve graft is indicated. Common choices include sural, lateral, or medial antebrachial cutaneous. For the size and length of the defect and the fact that multiple cable grafts would be needed, the sural is the most appropriate choice.
Nerve conduits such as PGA tubes and processed human allograft conduits serve as scaffolds to promote nerve regeneration, although these are typically used for gaps less than 3 cm. Given the distance involved, a sural nerve graft using a grouped fascicular or epineurial repair is the most appropriate choice, although a gap this large is almost certain to leave permanent deficits. Appropriate levels of expectation must be set with the patient.
An otherwise healthy 62-year-old woman presents with mild edema, some hemosiderin deposition, and a clean, shallow, painful ulcer about 2 cm in size above the left medial malleolus. Medical history includes a left ankle fracture 15 years ago. She does not smoke cigarettes. She has a job which requires that she stand for 8-hour shifts. Distal pulses are present and ankle brachial index is .94. Which of the following is the most appropriate initial management?
A) Debride the wound and apply a split-thickness skin graft
B) Elevate and apply serial compression dressings (Unna boot)
C) Hyperbaric oxygen therapy (HBOT)
D) Optimize the wound bed with bilaminate neodermis (Integra)
E) Strip the greater saphenous vein and ligate the perforators
The correct response is Option B.
Venous insufficiency is staged using the CEAP (clinical, etiologic, anatomical, and pathophysiologic) classification. The patient presented in this scenario meets the criteria for C6 (Clinical 6) criteria with the presence of an active ulcer. Compression and keeping the wound clean are the initial, primary, and mainstay therapies for healing venous ulcers. The only option listed that provides compression and wound care is to clean the wound, elevate, and apply serial compression dressings (Unna boot). After a trial of compression and wound bed optimization, closure can be considered. The literature does not provide conclusive evidence that skin grafting is a superior or desired closure. There are studies that demonstrate the superiority of Apligraf in achieving wound closure. If the perforators are found to be the source of the issue, ligation may reduce the recurrence of ulcers in the area but studies comparing ligation and wound care do not show earlier closure of ulcers present. Hyperbaric oxygen therapy (HBOT) is not indicated in this situation.
A 45-year-old man with insulin-dependent diabetes mellitus develops a gangrenous toe. Culture of the wound shows mixed aerobic and anaerobic organisms, including Bacteroides, Enterococcus, and Staphylococcus. Noninvasive vascular studies show an ankle-brachial index of 0.76. The patient wishes to undergo a single-stage surgical procedure. Which of the following is the most appropriate type of amputation for this patient?
A) Amputation at the level of the metatarsophalangeal joint
B) Transmetatarsal amputation
C) Lisfranc amputation
D) Syme’s amputation
E) Below-knee amputation
The correct answer is option B.
Amputation is indicated in this patient who has obvious necrosis of the toe. Indeed, ischemic changes and wound problems are often seen in patients with diabetes mellitus. Because these patients are typically predisposed to further, more proximal amputations in the future, a conservative approach to amputation should be used in this instance. Several factors, including ankle-brachial index, help to predict the success rate in patients who undergo partial amputations of the foot; an ankle-brachial index of less than 0.7 indicates a markedly increased risk for wound healing problems following surgery. However, this patient has an ankle-brachial index of 0.76, which is an acceptable risk for complications following amputation. Therefore, an evaluation for the likelihood of revascularization should be undertaken prior to any amputation procedure. The surgeon should attempt to save as much of the foot as possible to allow for primary closure of the defect. As a result, the amputation should be performed at the metatarsal level in this patient. The surgeon should also be aware of the vascular supply to the adjacent toes during the amputation procedure in order to prevent any associated complications.
Which artery in the lower leg is most commonly injured?
A) Anterior tibial artery
B) Posterior tibial artery
C) Peroneal artery
D) Medial plantar artery
The correct answer is option A.
As a more superficial vessel, the anterior tibial artery is the most commonly injured vessel in lower extremity trauma (30-60%).
Chen 1994
During harvest of a plantaris tendon graft, which of the following structures is at greatest risk for injury?
A) Dorsalis pedis artery
B) Extensor hallucis brevis muscle
C) Medial plantar artery
D) Sural nerve
E) Tibial nerve
The correct response is Option E.
When multiple tendon grafts are needed or when it is necessary to harvest grafts long enough to reach from the forearm to the fingertip, lower extremity tendon graft harvest is necessary. The plantaris tendon is a good source of tendon graft and is present in about 80% of limbs.
The graft is harvested through a vertical incision just anterior to the medial aspect of the Achilles tendon. Then the graft is followed proximally using either a tendon stripper or with further incisions. As such, dissection of the plantaris tendon begins behind the medial malleolus and close to the tibial nerve. The sural nerve lies about the lateral malleolus and thus is not likely to be inadvertently injured during plantaris harvest. The medial plantar artery is on the sole of the foot and would be distal to the field of dissection. The extensor hallucis brevis muscle is a small muscle that lies over the dorsum of the foot and thus, like the dorsalis pedis artery, would not be injured in the dissection.
A 25-year-old man presents with a comminuted tibia plateau fracture sustained during a self-inflicted gunshot wound. A CT scan is shown. During open reduction and internal fixation of the fracture, a 5-cm gap in the common peroneal nerve is noted. Tendon transfer, nerve repair with grafting, and nerve transfer are planned. Which of the following fascicular nerve transfers is most likely to aid in ankle dorsiflexion?
A) Flexor digitorum longus to soleus
B) Flexor digitorum longus to tibialis posterior
C) Flexor hallucis longus to tibialis anterior
D) Peroneal longus to extensor digitorum longus
E) Soleus to extensor digitorum brevis
The correct response is Option C.
Common peroneal nerve repairs tend to have less favorable results than their upper extremity counterparts. Traction injuries showed only good outcomes in 42% of patients, whereas sharp injuries showed good results in 61% of patients. Gunshot wounds, on the other hand, showed only 49% good outcomes due to the blast injury. This patient had damage of his nerve from penetrating trauma from the fracture fragments as well as damage from the blast injury. Because of the size of the defect, primary nerve repair would not be feasible. Nerve grafts less than 6 cm have been found to have a more favorable result than those greater than 6 cm. When combined with blast injury, a favorable result has only been found in 31% of patients.
In addition to nerve repairs, tendon transfers of the posterior tibial tendon have been useful for more immediate dorsiflexion. Fascicular nerve transfers have found some success in dorsiflexion. Of the options given, only transfer from the flexor hallucis longus (tibial nerve) to the tibialis anterior (deep peroneal nerve) would result in dorsiflexion. Although flexor digitorum longus is a common donor from the tibial nerve, innervating the soleus would result in plantar flexion and the soleus is also innervated by the tibial nerve, so it was not injured in the gunshot. Transfer from the flexor digitorum longus to the tibialis posterior (tibial nerve) would plantarflex the foot and not dorsiflex it. Although transfer to the extensor digitorum longus can lead to dorsiflexion, transfer from the peroneal longus (superficial peroneal nerve) to extensor digitorum longus would not result in a functional nerve repair, since the peroneal longus is innervated by the damaged nerve. Finally, transfer from the soleus to the extensor digitorum brevis (EDB, deep peroneal nerve) would not be a nearby transfer, nor would the EDB dorsiflex the ankle.
A 17-year-old boy sustains an avulsion injury to the anterior ankle with exposed tendon in a motorcycle collision. The wound is evaluated and reconstruction with a reverse sural artery flap is planned. During elevation of the flap, which of the following is most likely to compromise flap viability?
A) Injury to the lesser saphenous vein
B) Injury to the median superficial sural artery
C) Injury to the sural nerve
D) Ligation of the gastrocnemius muscle perforators
E) Ligation of the peroneal artery perforators
The correct answer is option E.
The predominant blood supply to the reverse sural artery flap relies on perforators from the peroneal artery, which primarily originate at a point 5 cm proximal to the lateral malleolus. The median superficial sural artery and perforators from the gastrocnemius are involved in anterograde blood supply to the flap. Thus, these vessels are typically ligated in the reverse form of the flap. Likewise, injury to the lesser saphenous vein would not cause significant problems with venous outflow. In dissections and venous flow studies, small concomitant veins were found along both sides of the lesser saphenous vein and were considered to be venae comitantes of accompanying arteries of the vein. These accompanying veins played a role in bypassing the valves of the lesser saphenous vein. The sural artery flap can be harvested as a neural-veno-adipofascial flap. In this context, the sural nerve can used to provide sensation to the flap. This nerve does not provide primary blood supply to the flap, and injury would not compromise flap viability.
A 55-year-old man is evaluated in the emergency department for foot salvage after he was involved in a motorcycle collision. Flow is restored after 6 hours from the time of injury. On examination, the foot is cold, and no plantar sensation is noted. The posterior tibial nerve is disrupted. A temporary external fixator is placed. A photograph and an x-ray study are shown. Which of the following is the most appropriate classification of this injury and recommendation for management?
A) Gustilo type IIIB; amputation
B) Gustilo type IIIB; reconstruction
C) Gustilo type IIIC; amputation
D) Gustilo type IIIC; reconstruction
The correct response is Option C.
The patient described has a Gustilo IIIC injury. Based on the best available data, he should undergo amputation.
Ultimately, the choice to reconstruct versus amputate is a gestalt of the situation and the patient, as well as the capabilities of the hospital and the care team. In this case, the factors influencing the decision would be the warm ischemia time of 6 hours and severed posterior tibial nerve, as well as the extensive soft-tissue injury.
Some of the newer data suggests that absence of plantar sensation is no longer criteria for amputation in and of itself. However, an anatomically disrupted nerve in an adult strongly favors amputation.
In addition, there is evidence supporting the notion that limb salvage might involve less cost in the long term versus reconstruction.
Gustilo Classification
I: open fracture; clean; wound less than 1 cm
II: open fracture; wound greater than 1 cm
IIIA: open fracture; extensive soft-tissue injury but adequate tissue for coverage
IIIB: open fracture; extensive soft-tissue injury but inadequate tissue for coverage
IIIC: any of the above with a vascular (arterial) injury
An 18 year old man comes to the office for follow-up examination becaus he has a four-month history of tripping with numbness and tingling of the right leg and foot. He underwent arthroscopic anterior cruciate ligament (ACL) grafting five months ago after he dislocated the right knee and ruptured the ACL during a football game. Physical examination shows weakness of dorsiflexion of the foot. Decreased sensibility to light touch over the lateral aspect of the right leg is noted. Which of the following is the most likely cause of his symptoms?
(A) Compartment syndrome
(B) Compression of the common peroneal nerve
(C) Laceration of the deep peroneal nerve
(D) Laceration of the superficial peroneal nerve
(E) Neurapraxia of the tibial nerve
The correct response is Option B.
Compression of the common peroneal nerve is the third most common nerve compression syndrome (carpal tunnel syndrome is first and cubital tunnel syndrome is second) and the most common nerve compression syndrome in the lower extremity. Knee dislocations are a common cause of common peroneal nerve compression. The patient described has a chronic injury that has not caused complete paralysis or loss of sensibility. The initial injuries would likely cause scar tissue around the knee but are not sharp in nature. Compression of the common peroneal nerve would result in weakness in the anterior compartment muscles caused by slowing of conduction in the deep peroneal nerve and paresthesias to the superolateral foot caused by slowing of conduction in the superficial peroneal nerve.
Compartment syndrome is caused by elevation of interstitial pressure (>30 mmHg) in the closed fascial compartment that results in microvascular compromise often secondary to a crushing injury or a high-force trauma. As duration and magnitude of interstitial pressure increase, myoneural function is impaired and necrosis of soft tissues eventually develops. Symptoms of an anterior compartment syndrome include extreme pain out of proportion to the injury and painful plantar flexion of the foot and toes.
The superficial peroneal nerve travels in and supplies the muscles of the lateral compartment of the leg. This nerve can be injured during an open reduction and internal fixation of a fracture of the ankle. A laceration of this nerve would not cause foot drop. The deep peroneal nerve travels in and supplies the muscles to the anterior compartment. Laceration of this nerve would cause foot drop but not decreased sensibility to the leg.
A neurapraxia of the tibial nerve at the level of the knee would affect the plantar flexors of the foot and toes. A tibial nerve injury would also cause planar foot paresthesias, which is the opposite of what the patient described is experiencing.
An otherwise healthy 47-year-old man is transferred to the hospital because of an infection of the leg. He sustained the initial injury in a fall 6 weeks ago that was treated with internal fixation. The infection is now under control, and the internal hardware has been removed. Examination shows a 9-cm bony defect of the lower extremity. Neurovascular status of the foot is normal. Angiography of both lower extremities shows no abnormalities. A photograph and x-ray study are shown. Which of the following considerations favors vascularized bone grafting in this patient?
A) Length of time since the initial injury
B) Mechanism of the injury
C) Method of injury stabilization
D) Patient age
E) Size of the bony defect
The correct response is Option E.
The injury described is a Gustilo IIIB lower extremity wound complicated by infection. The sequence of reconstruction is often bony stabilization and debridement until bacterial balance. Bony deficits can be reconstructed in a variety of ways, including non-vascularized grafts, vascularized grafts (free of pedicle), and bone transport.
Generally, for defects greater than 6 to 8 cm, vascularized bone grafting is indicated.
Other indications for vascularized bone grafting are the presence of infection and prior failure of conventional (non-vascularized) grafting.
Age of the patient is not a contraindication to reconstruction per se, as long as he or she is medically stable to undergo a prolonged operation.
Gustilo Classification
I: open fracture; clean; wound less than 1 cm
II: open fracture; wound greater than 1 cm
IIIA: open fracture; extensive soft-tissue injury but adequate tissue for coverage
IIIB: open fracture; extensive soft-tissue injury but inadequate tissue for coverage
IIIC: any of the above with a vascular (arterial) injury
A 65-year-old man comes to the office because of an infected wound to the left plantar region. Medical history includes type 2 diabetes mellitus. Dorsalis pedis and posterior tibial pulses are not palpable but are located with a handheld Doppler probe. Ankle brachial index cannot be obtained because of noncompressible vessels in the left lower extremity, below the knee. Which of the following is the most appropriate next step in evaluating the arterial perfusion of this patient’s foot?
A) Computed tomography arteriography
B) Magnetic resonance arteriography
C) Percutaneous arteriography
D) Repeat ankle brachial index
E) Toe brachial index
The correct response is Option E.
The most appropriate next step when evaluating the arterial perfusion of this diabetic patient’s foot is obtaining a toe-brachial index (TBI). TBI is calculated by dividing the great toe systolic pressure by the brachial systolic pressure. An index of >0.7 is considered normal.
Patients with diabetes mellitus have a higher incidence of peripheral arterial disease than the non-diabetic population. Atherosclerotic lesions in diabetic patients tend to favor the arteries below the knee, which also commonly display medial calcinosis, causing stiffening of the arterial walls, poor compressibility, and an unreliably high ankle-brachial index (ABI). Interestingly, the small vessels of the great toes are usually spared of disease, therefore the diagnostic advantage of TBIs. These features should be taken into consideration whenever assessing arterial blood flow to the distal lower extremity of a diabetic patient.
Percutaneous arteriography is an invasive procedure and should be reserved for when surgical or endovascular therapeutic interventions are anticipated. Computed tomography arteriography and magnetic resonance arteriography may also be used in the diagnosis of peripheral artery disease in the lower extremities, but a normal TBI would most likely preclude their need. Repeating the ABI would most likely render a similar result, as the inability to compress the arteries in the leg is due to stiffened vessel walls.
After prolonged ischemic time of 8 hours, you successfully perform a femoral, posterior tibial artery for an acutely threatened limb. Several hours post-operatively, the patient develops a swollen, painful leg that feels tight on exam. He has pain on passive range of motion. The most appropriate next step is:
A) Fasciotomy
B) Arterial bypass
C) Elevation and observation
D) Hydration
The correct answer is option a.
fasciotomy- reperfusion injury can result in compartment occur after prolonged ischemia times. Treatment is four compartment release
A thin 40-year-old woman has an 8 × 5-cm skin defect in the distal third of the anterior leg extending to the dorsum of the foot, with tibia denuded of periosteum and exposed tendon, after undergoing stabilization of the fracture with internal hardware 3 days ago. The distal posterior tibial artery was ligated before surgery at the distal third of the leg. There are no signs of infection or osteomyelitis. Which of the following is the most appropriate method of reconstruction?
A) Application of bilaminate neodermis (Integra) and negative pressure wound therapy
B) Coverage with a dorsalis pedis flap
C) Coverage with a free anterior lateral thigh (ALT) flap
D) Coverage with a free tranverse rectus abdominus myocutaneous (TRAM) flap
E) Coverage with a reverse sural flap
The correct response is Option C.
A free anterior lateral thigh flap is large enough to close the defect, can be thinned for aesthetics and shoe wear, and may allow for primary closure of the donor site. Although free tranverse rectus abdominus myocutaneous (TRAM) flap coverage is a possibility, the potential complications of taking muscle and unpredictable control of the final contour make them less ideal options. The reverse sural flap is not an option because of the ligation of the posterior tibial artery. In addition to having severe donor site morbidity, the dorsalis pedis would remove the remaining blood supply to the foot. The vascular nature of the defect’s wound bed makes bilaminate neodermis (Integra) and negative pressure wound therapy a less optimal choice.
A 42-year-old man sustains open fractures of the tibia and fibula (Gustilo type IIIB) when he is thrown from his motorcycle. The wounds are irrigated, debrided, and covered with a free flap. Which of the following will NOT increase this patient’s risk for the development of osteomyelitis?
A) Dead space at the surgical site
B) Inadequate soft-tissue coverage
C) Internal fixation
D) Presence of nonviable muscle
E) Retention of devitalized bone
Correct answer is option C.
Patients who sustain open fractures of the long bones are susceptible to bacterial invasion of the wound site and the subsequent development of infection, especially osteomyelitis. Factors associated with persistent infection include the presence of dead space at the surgical site, inadequate soft-tissue coverage, the presence of nonviable soft tissue, including muscle, and retention of devitalized bone. Aggressive irrigation and debridement should be performed in any patient with an open fracture. All nonviable tissue must be removed, and the fracture site should be covered with adequate soft tissue from a local site or via a free tissue transfer. Internal fixation has not been associated with development of osteomyelitis in patients who have open fractures of the tibia and/or fibula.
A 40-year-old man presents to the emergency department because of severe pain after sustaining a crush injury to the left lower extremity from a forklift. On physical examination, the lower leg is tense and swollen circumferentially. Sensation to the foot is diminished. Distal pulses are palpable. X-ray study does not show any fractures. Which of the following is the most appropriate next step in management?
A) Ace wrap compression
B) CT angiography
C) Emergent fasciotomy
D) MRI
E) Observation and leg elevation
The correct response is Option C.
The patient displays the signs and symptoms of acute compartment syndrome, a surgical emergency requiring emergent fasciotomy. Acute compartment syndrome requires prompt diagnosis and expeditious treatment in order to minimize morbidity. Compartment syndrome can occur following a substantial soft tissue crush injury, even in the absence of a fracture, such as in this clinical scenario. Severe pain is usually the presenting complaint. It may be out of proportion to the injury and unresponsive to analgesics. The presence of paresthesias can signify nerve hypoxia from elevated compartment pressures. Pallor, paralysis, and pulselessness are very late signs. Nerve and muscle do not tolerate long periods of ischemia and may undergo irreversible damage if surgical decompression is delayed.
Compartment syndrome is primarily a clinical diagnosis, but measurement of compartment pressures can provide additional information especially if the diagnosis of compartment syndrome is less obvious. If compartment pressures are greater than 30 mmHg or if the differential pressure (difference between diastolic blood pressure and compartment pressure) is less than 30 mmHg, then fasciotomy is recommended.
Observation and leg elevation would not be appropriate management in the setting of acute compartment syndrome. CT angiography would not be indicated in this case, where there is a low suspicion of vascular injury. MRI has been used in the diagnosis of chronic exertional compartment syndrome but has little value in the setting of acute trauma.
A 77-year-old man has a 4 x 3-cm defect of skin and soft tissue over the distal third of the tibia after he had a stroke and fell. He has a history of myocardial infarction and chronic obstructive pulmonary disease. Physical examination of the lower leg shows exposed bone and desiccated periosteum; there is no fracture. Which of the following is most appropriate for reconstruction of the defect?
A) Full-thickness skin graft
B) Cross-leg flap
C) Fasciocutaneous flap
D) Gastrocnemius flap
E) Free tissue transfer
Correct answer is option C.
The most appropriate management is coverage of the defect with a fasciocutaneous flap. This flap is ideal for reconstruction of lower extremity wounds in patients with severe illness or multiple trauma, or in patients with small wounds that cannot be covered with a skin graft alone. The fasciocutaneous flap can be based either proximally or distally on various septocutaneous perforators, including those of the medial leg (which lie approximately 3 cm posterior to the tibia), the posterolateral septum, and the anterolateral leg. Skin grafting should not be performed over bone that is exposed and lacks periosteum. Some surgeons have recently described a technique for grafting over exposed bone, in which holes are drilled into the bone to allow for granulation and grafting is then performed. However, this process is not the best option in an elderly patient with multiple medical problems. The gastrocnemius flap is appropriate for defects of the upper and sometimes middle third of the leg, but lacks the adequate reach for defects of the distal leg. Cross-leg flaps are rarely used now because of the availability of free tissue transfer. This flap is more appropriate in children than elderly patients, in whom stiffness is a factor. Free tissue transfer is not an option in a patient who has had serious medical conditions, including stroke, myocardial infarction, and pulmonary disease.
A 40-year-old man sustains an avulsion of the weight-bearing portion of the medial heel. Coverage with an instep flap is planned. Sensation to this flap is provided by which of the following?
A) Lateral plantar nerve from the deep peroneal nerve
B) Lateral plantar nerve from the superficial peroneal nerve
C) Lateral plantar nerve from the sural nerve
D) Medial plantar nerve from the deep peroneal nerve
E) Medial plantar nerve from the tibial nerve
The correct response is Option E.
The medial plantar artery flap, or instep flap, provides sensate, full-thickness glabrous skin and subcutaneous tissue that can be transferred as a pedicled or free flap. The tissue is well suited for weight-bearing areas of the foot but has also been used as a free tissue transfer for palmar defects. Because the instep donor site is non–weight-bearing, the donor site can be covered with a skin graft. The innervation of the medial instep flap comes from the medial plantar nerve, a branch of the tibial nerve.
A 37-year-old man comes to the office because of wound breakdown 2 weeks after he sustained a calcaneal fracture. Orthopaedic stabilization was performed in the emergency department at the time of the injury. Examination today shows a 3 × 4-cm wound over the lateral calcaneus. Coverage with a propeller fasciocutaneous flap from the lateral leg is planned. Which of the following blood vessels supplies the perforators of this flap?
A) Anterior tibial artery
B) Lateral plantar artery
C) Lateral sural artery
D) Peroneal artery
E) Posterior tibial artery
The correct response is Option D.
Propeller flaps are a useful method of lower extremity reconstruction. These flaps were initially popularized by Teo and have been utilized for a variety of defects in the lower leg and foot. The propeller flap is based on perforating blood vessels from the peroneal artery to reconstruct lateral defects and perforators from the posterior tibial artery to reconstruct defects on the medial aspect of the leg wound. The propeller flaps can often replace the need for a sural artery, neurocutaneous artery flap or a free tissue transfer. Laterally based plantar flaps may be used to cover small defects on the weight-bearing surface of the foot but are not reliable for larger or lateral defects. The posterior and anterior tibial arteries do not have perforator in the desired location for a distally based propeller flap. The lateral sural vessels are too proximal for heel coverage.
Compared to muscle free flaps for lower extremity trauma reconstruction, fasciocutaneous flaps have comparable rates of which of the following:
A) Flap thrombosis
B) Flap salvage
C) Limb salvage
D) Secondary revisions
E) All of the above
The correct answer is option E.
For lower extremity reconstruction in trauma patients, multiple studies comparing fasciocutaneous free flaps and muscle free flaps have shown no difference in flap thrombosis or flap loss, limb salvage, infection, bone healing, and functional recovery. Both types of flaps also undergo similar rates of secondary revisions.
Yazar 2004, Cho 2017 The correct answer is option E.
A 29-year-old man undergoes open reduction and internal fixation of an open fracture of the proximal right tibia. There is no tissue loss, and there is little wound contamination. The wound is closed with 2-cm raised flaps. Reconstruction of the popliteal artery is required. Which of the following Gustilo fracture classifications is most likely in this patient?
A) I
B) II
C) IIIA
D) IIIB
E) IIIC
The correct response is Option E.
Gustilo initially classified long-bone fractures into three types in order to establish a treatment algorithm. Essentially, this classification subdivided fractures according to the energy of the initial trauma that resulted in significant soft-tissue injury, periosteal stripping, and fracture comminution in the worst subtype. Debridement, antibiotics, and primary or delayed wound closure were advocated dependent on fracture severity. Type III fractures were subsequently subdivided into A, B, and C subtypes. Subtypes were stratified according to potential for complications such as infection, osteomyelitis, non-union, and amputation rates. Type IIIC had open fracture with arterial injury requiring repair (the case in this patient, even though there appears to be adequate soft-tissue coverage).
Although fracture fixation methods have substantially improved since the original publications of Gustilo, the ability to transport bone into segmental traumatic defects has also since developed, and free flaps have extended our ability to cover large wounds. This classification system has stood the test of time and still forms the basis of prognosticating and determining the optimum treatment algorithm.
A 43-year-old man has footdrop and numbness of the left foot following reconstruction of a soft-tissue defect resulting from a Gustilo Type IIIB fracture of the proximal tibia. Which of the following pedicled flaps was most likely used for reconstruction?
A) Gracilis
B) Lateral gastrocnemius
C) Reversed sural artery
D) Sartorius
E) Soleus
Correct answer is option B.
The pedicled gastrocnemius flap has been shown to be a reliable source of vascularized soft tissue for injuries of the distal thigh, knee, and proximal leg. The lateral or medial head may be harvested. Lateral gastrocnemius harvest risks damaging the common peroneal nerve, with an incidence of 7.7%. Medial gastrocnemius harvest, for obvious anatomical reasons, does not carry this risk. There are few data on the morbidity of donor sites, but those studies that have been done demonstrate no functional debility at a walking gait for less than 200 m. Patients do notice difficulty standing on their toes and have slowing with variable calcaneal gait when walking fast. Forty-two percent of patients could run, 22% had pain in the donor site at rest, and 20% had pain when walking more than 200 m. Seventy percent had pain and weakness in the operated leg when attempting to run. Range-of-motion deficit existed in the operated limb, with average loss of 27% flexion and 14% extension. The gracilis and sartorius muscles are not routinely used for pedicled reconstruction of the proximal tibia, nor would their harvest cause the symptoms of the patient described. The reversed sural artery flap is an adipofascial flap that could be used for this described defect; however, its dissection does not jeopardize the common peroneal nerve. The soleus muscle has better venous muscle pump function than the gastrocnemius, and edema, not nerve damage, is more common after use of the gastrocnemius. The limited data available suggest that the functional deficit with resulting limitation to ankle flexion is also more severe with soleus harvest.
A 45-year-old man is brought to the emergency department after sustaining a fracture of the neck of the fibula after being struck by a baseball. Physical examination shows major nerve deficit. Which of the following actions will the patient be unable to perform?
A) Dorsiflex the foot
B) Extend the leg
C) Flex the leg
D) Invert the foot
E) Plantar flex the foot
The correct response is Option A.
The most commonly injured nerve in the leg is the common peroneal nerve because of its superficial location as it courses around the neck of the fibula. The common peroneal nerve then divides into the superficial and deep branches. The superficial branch will evert the foot by innervating the lateral compartment of the leg, while the deep branch will dorsiflex the foot by innervating the anterior compartment. The superficial branch also provides sensation for the anterior and lateral sides of the leg and the majority of the dorsum of the foot and toes, including the medial side of the big toe. Paralysis of the common peroneal nerve would lead to foot drop and foot inversion, abnormal “steppage” gait, and loss of sensation.
A 32-year-old woman comes to the office because the toes of the right foot “drag” when she walks. She underwent vein stripping of the right leg and ligation of the lesser saphenous vein 4 weeks ago. Physical examination shows absent dorsiflexion and eversion of the ankle. Electromyography findings show:
Which of the following is the most likely site of nerve injury in this patient?
A) Common peroneal nerve at the knee
B) Superficial peroneal nerve at the knee
C) Sural nerve at the knee
D) Tibial nerve at the knee
E) Tibial nerve at the mid calf
The correct response is Option A.
The most likely site of injury would be the common peroneal nerve at the knee. Injuries to the common peroneal nerve are well documented in both traumatic (knee dislocation) and iatrogenic settings. Patients have footdrop and numbness over the first dorsal web space of the foot. History and clinical examination are the mainstays for diagnosis, but electromyography can be helpful in less-clear circumstances. The absence of recruitment of the lateral compartment muscles (peroneals) and the anterior compartment muscles (tibialis anterior, extensor hallucis longus) strongly suggest common peroneal involvement. The presence of recruitment of the biceps femoris and the tibialis posterior rules out tibial nerve involvement. An isolated superficial peroneal nerve injury would spare the anterior compartment muscles.
The sural nerve is a sensory nerve and provides no motor function.
An otherwise healthy 30-year-old man is evaluated because of left foot drop after posterior knee dislocation. The common peroneal nerve is explored at the level of the knee shortly after the time of injury and found to be in continuity. The patient does not return for follow-up examination within the next year. Eighteen months after the injury, the patient returns for follow-up examination and shows no improvement of the foot drop. Passive range of motion of the ankle is full. Which of the following transfers is most likely to correct this patient’s foot drop deformity?
A) Peroneus brevis tendon with graft to calcaneus bone
B) Peroneus longus tendon to calcaneus bone
C) Peroneus longus tendon to talus bone
D) Tibialis anterior nerve to tibialis posterior nerve
E) Tibialis posterior tendon to tibialis anterior tendon
The correct response is Option E.
Common peroneal nerve injury is common after posterior knee dislocation, usually occurring at or near where the nerve crosses the fibula neck. After surgical exploration to confirm the peroneal nerve is intact, initial management consists of supportive care with an ankle brace to correct foot drop. Patients are observed clinically for recovery, often with serial electromyography and nerve conduction studies.
Tibialis posterior to anterior transfer will restore the patient’s ability to dorsiflex the ankle. The donor muscle is innervated by the tibial nerve, which is not commonly injured in a posterior knee dislocation. The tendon is dis-inserted from the tarsus and brought out through the medial leg.
It is transferred through the interosseous membrane to the tibialis anterior tendon.
By 18 months after injury, the motor end plates to the tibialis anterior have degenerated, making a nerve transfer no longer an option. Earlier after injury, a nerve transfer from the tibialis posterior to the tibialis anterior might be a feasible option.
Peroneus longus and brevis would also be paralyzed in the setting of a common peroneal nerve injury such as this patient’s. In certain situations, such as with some patients with leprosy, the deep peroneal nerve is not paralyzed. For these patients, the peroneus longus can be used as a tendon transfer, but it is normally used to provide toe extension in conjunction with a tibialis posterior transfer to provide ankle dorsiflexion.
A 62-year-old woman with non-insulin-dependent diabetes mellitus is undergoing lower extremity angiogram to determine her suitability for forefoot reconstruction. Which of the following is the most appropriate therapy for the prevention of contrast-induced nephropathy in this patient?
A) Ascorbic acid
B) Intravenous saline
C) N-acetylcysteine
D) Simvastatin
E) Sodium bicarbonate
The correct response is Option B.
Contrast-induced nephropathy (CIN) is a significant problem in patients undergoing procedures that require contrast administration. The mechanism is believed to be an ischemic injury to the renal medulla. It is the third most common cause of hospital-acquired renal failure. Independent of renal failure, the development of even mild CIN is associated with increased rates of morbidity and mortality. The major risk factor for developing CIN is pre-existing renal dysfunction. This is particularly associated with patients with diabetes and those who have a creatinine clearance less than 60. The best method of prevention is appropriate risk stratification, intravenous hydration with normal saline and withholding of nephrotoxic medications. Intravenous fluid hydration with normal saline is the mainstay of practice in the prevention of CIN. It is low-risk, carries few side effects, and is cost-effective. Randomized trials have found intravenous hydration with normal saline to be consistently effective. The administration of intravenous fluids increases intravascular volume, promotes diuresis, diminishes the overall intravascular contrast load and supports vasodilation. Although intravenous administration of sodium bicarbonate has also gained popularity in the prevention of CIN, recent publications have demonstrated mixed results. The use of N-acetylcysteine, statin drugs and ascorbic acid are not recommended for the prevention of CIN.
A 14-year-old girl comes to the office for follow-up examination seven days after undergoing intramedullary nail fixation of a fracture of the right tibia. Along with bony stabilization, the degloved skin from the posterior middle and distal third of the leg was tacked back in place. On physical examination, necrosis of the replaced skin is noted. After debridement, the tibia is exposed in the middle to distal third of the leg. Which of the following is the most appropriate management?
(A) Split-thickness skin graft
(B) Sural artery flap
(C) Soleus flap
(D) Free latissimus flap
(E) Amputation
The correct response is Option D.
This Gustilo IIIB wound is best covered with a free muscle flap. The latissimus muscle flap is an effective and frequently used flap for large wounds. This flap also has the advantage of large vessels and a long pedicle length.
Dressing changes followed by a skin graft will not provide durable coverage over the tibia, is not appropriate in a healthy teenager who is not at surgical risk, and the time delay to coverage may predispose the patient to the development of osteomyelitis. A neuroadipofascial flap based on the vessels accompanying the sural nerve would be a poor choice, as this would be harvested from the zone of injury. The soleus flap is traditionally used for middle third defects of the leg and also is within the zone of injury. This is a salvageable extremity in a young teenager, which makes amputation inappropriate.
A 65-year-old attorney has severe ischemia of the right leg. On examination, the leg is gangrenous and ulcerated; he has pain with motion and at rest. Noninvasive vascular studies show an ankle-brachial index of 0.16. He refuses to undergo amputation.
Which of the following is the most appropriate technique for limb salvage?
(A) Distal arterial bypass
(B) Distal venous arterialization bypass
(C) Endovascular stent placement
(D) Free muscle transfer
(E) Lumbar sympathectomy
The correct response is Option B.
The symptoms and findings of severe pain at rest, ulceration, and gangrene seen in this patient are indicative of limb ischemia, a critically urgent condition that results from occlusion of the pedal and crural arteries. Although amputation had been performed in the past for patients with this condition, distal venous arterialization bypass is now a recommended alternative method for limb salvage. According to one small study of 18 patients, limb salvage was successfully accomplished in 83% of patients at surgery and 75% of patients at follow-up examination one year later. In these patients, the distal bypass was performed to the venous vessels of the foot using a conduit of either vein, synthetic graft, or a combination of both. The valves of the venous system were destroyed, and arterial inflow was then provided by the most distal patent artery.
Because both the pedal and crural arteries are occluded in this patient, neither direct arterial bypass nor placement of an endovascular stent will address the problem. Both free muscle transfer and lumbar sympathectomy are associated with lower rates of limb salvage in patients with severe ischemia.
A 29-year-old man undergoes open reduction and internal fixation of an open fracture of the proximal right tibia. There is no tissue loss, and there is little wound contamination. The wound is closed with 2-cm raised flaps. Reconstruction of the popliteal artery is required. Which of the following Gustilo fracture classifications is most likely in this patient?
A) I
B) II
C) IIIA
D) IIIB
E) IIIC
Correct answer is option E.
Gustilo initially classified long-bone fractures into three types in order to establish a treatment algorithm. Essentially, this classification subdivided fractures according to the energy of the initial trauma that resulted in significant soft-tissue injury, periosteal stripping, and fracture comminution in the worst subtype. Debridement, antibiotics, and primary or delayed wound closure were advocated dependent on fracture severity. Type III fractures were subsequently subdivided into A, B, and C subtypes. Subtypes were stratified according to potential for complications such as infection, osteomyelitis, non-union, and amputation rates. Type IIIC had open fracture with arterial injury requiring repair (the case in this patient, even though there appears to be adequate soft-tissue coverage). Although fracture fixation methods have substantially improved since the original publications of Gustilo, the ability to transport bone into segmental traumatic defects has also since developed, and free flaps have extended our ability to cover large wounds. This classification system has stood the test of time and still forms the basis of prognosticating and determining the optimum treatment algorithm. The Gustilo grading scale: Type Findings I Clean wound bed, simple/minimally comminuted bone injury, wound <1 cm II Wound contaminated, moderate comminution of bone, wound >1 cm IIIA Wound highly contaminated, severe comminution, wound 1 to 10 cm IIIB Wound highly contaminated, severe comminution, wound >10 cm IIIC Major vascular injury requiring repair for limb salvage
The percentage of persons who have absence of the plantaris muscle in one lower extremity is
(A) less than 5%
(B) 10% to 15%
(C) 25% to 30%
(D) 45% to 50%
(E) 75% to 80%
The correct response is Option B.
According to the results of several studies, the plantaris muscle has been shown to be absent in at least one lower extremity in approximately 10% to 15% of persons. This tendon can be used for grafting procedures. It provides a longer donor graft than the palmaris longus in the forearm; however, it is hidden on physical examination, making it more difficult to locate prior to surgery. Because the muscle may be absent in one or both lower extremities, ultrasonography can be helpful in determining its presence and location. Approximately 33% of patients have a plantaris muscle in only one lower extremity.
Other studies have shown that absence of the plantaris muscle occurs with slightly greater frequency in women, and the plantaris muscle is more likely to be absent in the left lower extremity. Differences based on race and/or ethnicity have not been studied. In addition, absence of the plantaris muscle is unrelated to absence of the palmaris longus muscle; in other words, a person who is missing one or both plantaris muscles may in fact have one or both palmaris longus muscles.
A 14-year-old girl comes to the office for follow-up examination seven days after undergoing intramedullary nail fixation of a fracture of the right tibia. Along with bony stabilization, the degloved skin from the posterior middle and distal third of the leg was tacked back in place. On physical examination, necrosis of the replaced skin is noted. After debridement, the tibia is exposed in the middle to distal third of the leg. Which of the following is the most appropriate management?
(A) Split-thickness skin graft
(B) Sural artery flap
(C) Soleus flap
(D) Free latissimus flap
(E) Amputation
The correct response is Option D.
This Gustilo IIIB wound is best covered with a free muscle flap. The latissimus muscle flap is an effective and frequently used flap for large wounds. This flap also has the advantage of large vessels and a long pedicle length.
Dressing changes followed by a skin graft will not provide durable coverage over the tibia, is not appropriate in a healthy teenager who is not at surgical risk, and the time delay to coverage may predispose the patient to the development of osteomyelitis. A neuroadipofascial flap based on the vessels accompanying the sural nerve would be a poor choice, as this would be harvested from the zone of injury. The soleus flap is traditionally used for middle third defects of the leg and also is within the zone of injury. This is a salvageable extremity in a young teenager, which makes amputation inappropriate.
The most commonly injured nerve with lower extremity fasciotomy is:
A) Superficial peroneal
B) Common peroneal
C) Tibial
D) Peroneal
Correct answer is option a.
Superficial peroneal nerve is very superficial at the area between the anterior and lateral compartments near the proximal fibula (near the fibular head). The two incision technique will be in close proximity to the superficial peroneal nerve. -
A 19-year-old man is brought to the emergency department after sustaining a heavily contaminated, open fracture of the tibia during an all-terrain vehicle collision. The injury is classified as a Gustilo Type IIIB fracture of the tibia in the distal third of the right leg. A comminuted 4-cm segment of the tibia is debrided. A soft-tissue defect measuring 7 * 4 cm overlies the fracture site. Which of the following is the most appropriate initial method to stabilize the fracture?
A ) Contralateral free fibula flap with intramedullary rod stabilization
B ) Iliac crest bone graft with plate stabilization
C ) Ipsilateral pedicled fibula flap with intramedullary rod stabilization
D ) Placement of an antibiotic-impregnated spacer
E ) Placement of an external fixation device
The correct response is Option E.
The most appropriate initial step for fracture stabilization is placement of an external fixation device. The patient described will require multiple debridements for the heavy contamination, followed by a free muscle flap to provide soft-tissue coverage of the exposed tibia fracture, and a future avascular bone graft for the 4-cm segmental bone loss.
Intramedullary rod stabilization for the initial management of open fractures of the tibia has gained increasing popularity in the orthopaedic literature, but the bone fixation is converted from external fixation to an intramedullary rod within the first 10 days of injury immediately prior to muscle flap coverage.
Although reported in the literature, the use of the ipsilateral fibula has been criticized, especially in trauma cases, because of (1) the loss of the mechanical integrity of the limb, which is especially useful to maintain limb length; (2) the loss of the peroneal artery in a traumatized limb; and (3) the loss of the origins of the deep muscles, which contributes an additional 30% loss of strength in an already traumatized and weakened extremity.
A 4-cm segmental bone loss does not require vascularized bone by either a pedicled or free bone flap.
Plate stabilization of the tibia fracture described is not indicated because of the heavy contamination and the soft-tissue loss. Also, avascular bone grafts are not recommended in the initial management of open lower extremity wounds because of the risk of graft loss secondary to infection.
An antibiotic-impregnated spacer could be used to help prevent infection, but it is not the initial step for fracture stabilization.
A 37-year-old man comes to the office because of wound breakdown 2 weeks after he sustained a calcaneal fracture. Orthopaedic stabilization was performed in the emergency department at the time of the injury. Examination today shows a 3 × 4-cm wound over the lateral calcaneus. Coverage with a propeller fasciocutaneous flap from the lateral leg is planned. Which of the following blood vessels supplies the perforators of this flap?
A) Anterior tibial artery
B) Lateral plantar artery
C) Lateral sural artery
D) Peroneal artery
E) Posterior tibial artery
The correct response is Option D.
Propeller flaps are a useful method of lower extremity reconstruction. These flaps were initially popularized by Teo and have been utilized for a variety of defects in the lower leg and foot. The propeller flap is based on perforating blood vessels from the peroneal artery to reconstruct lateral defects and perforators from the posterior tibial artery to reconstruct defects on the medial aspect of the leg wound. The propeller flaps can often replace the need for a sural artery, neurocutaneous artery flap or a free tissue transfer. Laterally based plantar flaps may be used to cover small defects on the weight-bearing surface of the foot but are not reliable for larger or lateral defects. The posterior and anterior tibial arteries do not have perforator in the desired location for a distally based propeller flap. The lateral sural vessels are too proximal for heel coverage.
A 47-year-old woman is referred by orthopedic surgery for evaluation and discussion of soft-tissue reconstruction at the time of nonvascularized allograft reconstruction of recurrent Achilles tendon rupture. The patient has a history of congenital clubfoot and multiple previous Achilles tendon repairs. Physical examination shows atrophied skin and multiple longitudinal scars along both the medial and lateral distal posterior calf. Which of the following is the most appropriate management?
A) Cross-leg fasciocutaneous flap
B) Fasciocutaneous free flap
C) Reverse sural artery flap
D) Soleus muscle flap
E) Tissue expansion
The correct response is Option B.
On the basis of the scenario described, fasciocutaneous free flap is the most appropriate management option.
The soleus muscle flap is appropriate for defects of the middle third of the leg but lacks adequate reach for soft-tissue coverage of the distal third of the leg.
Tissue expansion has been described for soft-tissue reconstruction of congenital talipes equinovarus but is usually reserved for children and in the setting of primary correction. When comparing tissue expansion in the limb versus non-limb sites, the incidence of complications associated with tissue expansion is significantly higher in the limb. Because a nonvascularized allograft is to be used, and the patient has a contracted and scarred soft-tissue envelope, tissue expansion would be associated with higher risk of expansion failure and complications when compared with free tissue transfer soft-tissue reconstruction.
Cross-leg flaps are rarely used because of the availability of free tissue transfer. This flap is more appropriate in children than elderly patients, in whom stiffness is a factor.
A reverse sural artery flap is not appropriate given the patient’s multiple past surgeries and local scars.
A 35-year-old man is brought to the emergency department 2 hours after sustaining a severe crush injury to the right distal thigh in a motor vehicle collision. Physical examination shows an open fracture of the femur; the leg and foot are pale and cool. There are no palpable popliteal, dorsalis pedis, or posterior tibialis pulses. Closed reduction does not restore perfusion. Which of the following is the most appropriate next step?
A) Arterial repair with a polytetrafluoroethylene graft
B) Arterial repair with reverse saphenous vein graft
C) CT angiography
D) Intramedullary fixation of the femoral fracture
E) Placement of a temporary vascular shunt
The correct response is Option E.
Gustilo Type IIIC fractures involve arterial injury requiring repair irrespective of the degree of soft tissue and often represent significant limb-threatening injuries. Early recognition and management of lower extremity vascular injury is crucial to limb salvage. CT angiography is of little benefit in the presence of hard signs of vascular injury and can delay operative intervention as well as increase limb ischemia time.
The combination of vascular and orthopedic injuries requiring repair is rare, with a reported incidence as low as 1.5%. Data exist from both wartime and civilian groups evaluating the sequence of management of such injuries. The recommended algorithm suggests improved ischemia times and favorable limb salvage rates with temporary vascular repair, using shunts as the initial adjunct to restore perfusion followed by debridement and fracture fixation.
Definitive vascular repair should follow debridement and fracture fixation. Both synthetic polytetrafluoroethylene and autologous (reverse saphenous vein) interposition grafts are reported to be used in traumatic reconstruction, although autologous tissue is often preferred in the setting of gross contamination.
A 67-year-old man comes to the office because of an open wound of the right groin and exposed distal anastomosis of a vascular graft 3 weeks after aortofemoral bypass grafting. Reconstruction with a sartorius muscle flap is planned to cover the graft. The blood supply of the sartorius muscle flap originates directly from which of the following arteries?
A) Deep circumflex iliac
B) Lateral circumflex femoral
C) Medial circumflex femoral
D) Profunda femoris
E) Superficial femoral
The correct response is Option E.
The sartorius muscle has a Type IV vascularization pattern consisting of 8 to 10 pedicles from the superficial femoral vessel, which enter the muscle medially. The other arteries do not contribute to the blood supply of the sartorius muscle.
A 35-year-old man presents for evaluation of a laceration to the lateral aspect of the right lower leg 5 cm distal to the knee that he sustained when he fell from a bicycle 2 months ago. Findings on electromyography and nerve conduction studies are consistent with an isolated complete injury of the common peroneal nerve. Which of the following deficits is most likely on physical examination?
a. Dorsiflexion of ankle
b. Plantarflexion of great toe
c. Sensation of lateral foot
d. Sensation of medial foot
e.Sensation of plantar foot
The correct response is Option A.
The common peroneal nerve forms as the sciatic nerve bifurcates at the apex of the popliteal fossa. It then follows the medial border of the biceps femoris muscle and tendon. The nerve then passes over the posterior aspect of the fibular head and winds around the neck of the fibula. The common peroneal then divides into the deep and superficial peroneal nerve branches. The deep branch supplies the anterior muscles of the leg, the dorsum of the foot, and the skin of the first web space. The superficial branch supplies the peroneus longus and brevis muscles and the skin on the distal third of the lower leg and dorsum of the foot. Because of its relatively superficial position, the common peroneal nerve is the most commonly injured nerve of the lower extremity. Transection of the common peroneal nerve results in paralysis of all muscles in the anterior and lateral compartments of the leg (dorsiflexors and ankle evertors). This pattern of injury results in the classic picture of a foot drop. The distribution of sensory loss would include the anterolateral leg and dorsum of the foot.
Sensation of the medial foot is from the saphenous nerve and branches of the medial plantar nerve. Lateral foot sensation is provided by the sural nerve. Sensation of the plantar aspect of the foot is from the terminal branches of the tibial nerve (medial and lateral plantar nerves). All of the muscles of plantar flexion of the ankle and toes (i.e. gastrocnemius, soleus, plantaris, and tibialis posterior, flexor hallucis longus, flexor digitorum longus, and the intrinsic plantar foot muscles) are innervated by the tibial nerve.
Reference(s)
- Anderson JC. Common fibular nerve compression: anatomy, symptoms, clinical evaluation, and surgical decompression. Clin Podiatr Med Surg. 2016 Apr;33(2):283-291.
- Kleiber GM, Parikh RP. Comprehensive lower extremity anatomy. In: Song D, e. Volume 4: Lower Extremity, Trunk, and Burns. Philadelphia, PA: Elsevier Churchill Livingstone; 2017:1-52. Plastic Surgery; Neligan PC, ed.
A 35-year-old man comes to the office for evaluation of purulent drainage from the surgical wound one year after open reduction and internal fixation of tibia and fibula fractures sustained in a motorcycle collision. Radiographs show osteomyelitis and nonunion of tibia and fibula fractures. He is taken to the operating room for debridement of scarred and fibrotic soft tissue, removal of hardware, and application of external fixation. A cutaneous scapula free flap is used to close an 8-cm defect. Intravenous antibiotics are initiated and continued for six weeks. Three months later, the purulent drainage recurs. Which of the following is the most likely cause of treatment failure?
A) Flap closure was under tension
B) Inadequate antibiotic therapy
C) Inadequate bone debridement
D) Use of a cutaneous scapula free flap rather than a muscle free flap
E) Use of a one-stage rather than a two-stage procedure
The correct response is Option C.
Lower extremity osteomyelitis following trauma is a challenging problem with high complication rates. The key to success is adequate debridement of both bone and soft tissue followed by coverage with vascularized tissue. The patient described had debridement of soft tissue but not bone. The bone is a persistent source of infection and the scarred fibrotic soft tissue is poorly vascularized, thus crippling the immune response. Without adequate bone debridement, early recurrence is likely. Muscle flaps fill the resultant defect, enhance blood flow, and improve immunologic defense against microorganisms.
The scapula flap can easily provide skin paddles of 10 × 15 cm; therefore, closure under tension would not be a problem.
A 50-year-old female has been diagnosed with osteomyelitis of her left tibia. The infection is isolated to the medullary canal of the bone, and her past medical history is significant for heavy smoking and chronic venous stasis. Based on the clinical staging of osteomyelitis, what would be her Cierney-Mader classification?
a. Stage 1
b. Stage 2
c. Stage 3
d. Stage 4
Correct answer is option a.
A 42-year-old man presents with an open tibia fracture sustained during a motor vehicle collision 4 hours ago. Physical examination shows a 3-cm puncture wound at the fracture site, no dirt or debris in the wound, and no exposed bone. X-ray studies show a transverse fracture of the tibia and fibula without comminution. Which of the following is the appropriate initial antibiotic coverage?
A) First generation cephalosporin
B) First generation cephalosporin, aminoglycoside, and penicillin
C) First generation cephalosporin and aminoglycoside
D) Third generation cephalosporin
E) Third generation cephalosporin, aminoglycoside, and penicillin
The correct response is Option A.
The Gustillo-Anderson classification system is used to grade open fractures based on the extent of bone and soft tissue injury, and the extent and nature of wound contamination. Aggressive debridement, administration of prophylactic antibiotics, application negative pressure dressing while the wound is open, and early definitive wound coverage (less than 5 days) reduces the infection risk. The open fracture described is a grade II injury and a first-generation cephalosporin alone provides appropriate antibiotic coverage. A concurrent vascular or neural injury or gross contamination could escalate this into a grade III injury, but there is no mention of these factors in the clinical scenario described.
A 17-year-old boy undergoes resection of the right distal femur to treat osteosarcoma. A large allogeneic corticocancellous bone graft is used for skeletal reconstruction of the 10-cm bony defect. An intramedullary vascularized fibular free flap is also placed in the construct. Which of the following is the most likely purpose of this additional procedure?
A) Decrease the immunogenicity of the allograft
B) Decrease the rate of infection
C) Increase creeping substitution in the allograft
D) Increase the immediate strength of the construct
E) Shorten union time
The correct response is Option E.
The most likely reason to place an intramedullary fibular free flap in the allogeneic bone graft is to shorten union time. Free fibular flaps contain an intrinsic blood supply and osteogenic cells. These offer an alternative to the allograft and the capability of osteogenesis through osteoinduction. Thus, the biologic advantage of fibular free flaps is a shortened union time compared with the allograft, which solely depends upon creeping substitution for healing. Union times may be as short as 3 to 5 months. The healing of massive allografts is generally slow, superficial, and incomplete. The union times for allograft healing have been reported at 14 to 23 months for intercalary defects.
Nonvascularized massive allografts provide a biologic spacer with strong cortical bone. These grafts give great strength to the construct; however, despite this advantage they have many disadvantages, including their lack of blood supply, lack of osteogenic cells, and potential for immunologic reaction. The fibula may add some strength to the overall construct but this is not the primary reason for its use in the scenario described. It also does not mitigate any potential antigenicity that the graft may have. The graft heals by creeping substitution and as such is only osteoconductive, unlike vascularized bone. This process in the allograft remains unchanged by the presence of the fibular flap; however, it does provide the additional process of osteoinduction as described above, which helps in healing. It is the avascular status of the allograft that predisposes these reconstructions to infection, not the dead space in the medullary canal.
A 53-year-old man with a comminuted fracture of the midtibia has a 4-by-3-cm defect of the midanterior surface of the leg at the level of the fracture. He currently smokes two packs of cigarettes daily. Physical examination shows no palpable dorsalis pedis pulse. Which of the following surgical interventions is the most appropriate method of reconstruction in this patient?
A) Anterior tibialis muscle flap
B) Below the knee amputation
C) Gastrocnemius muscle flap
D) Gracilis free tissue transfer
E) Soleus muscle flap
The correct answer is option E.
The soleus muscle flap is most appropriate for reconstruction in this patient. The soleus is a bipenniform muscle; its medial head originates from the posterior tibia, and the lateral head originates from the proximal fibula. It is located deep to the gastrocnemius in the superficial posterior compartment. Blood to the medial head is predominantly supplied by the popliteal and posterior tibial arteries and the lateral head is predominantly supplied by the peroneal artery. Depending on the size of the defect, a hemisoleus muscle flap can be used to preserve flexor function. Below-knee amputation is an option if salvage of the leg is not possible or if the extremity is insensate, particularly in older patients. An anterior tibialis muscle flap can be used for small defects. In this patient with an absent dorsalis pedis pulse and possible injury to the anterior tibial artery, this is not an optimum choice. For lower-extremity reconstruction, the gastrocnemius muscle flap is used for knee wounds and proximal tibial defects, the soleus for middle third defects, and free tissue transfer for distal third defects. The gastrocnemius muscle flap might not reach the defect in the middle third and therefore is not the best option. Free tissue transfer is often used for reconstruction of high-velocity injuries to avoid the use of muscle in the zone of injury. Free tissue transfer, however, is not the best option for this 53-year-old man because his history of cigarette smoking and absent pedal pulse suggest the possibility of peripheral vascular disease.
A 43-year-old man has footdrop and numbness of the left foot following reconstruction of a soft-tissue defect resulting from a Gustilo Type IIIB fracture of the proximal tibia. Which of the following pedicled flaps was most likely used for reconstruction?
A ) Gracilis
B ) Lateral gastrocnemius
C ) Reversed sural artery
D ) Sartorius
E ) Soleus
The correct response is Option B.
The pedicled gastrocnemius flap has been shown to be a reliable source of vascularized soft tissue for injuries of the distal thigh, knee, and proximal leg. The lateral or medial head may be harvested. Lateral gastrocnemius harvest risks damaging the common peroneal nerve, with an incidence of 7.7%. Medial gastrocnemius harvest, for obvious anatomical reasons, does not carry this risk.
There are few data on the morbidity of donor sites, but those studies that have been done demonstrate no functional debility at a walking gait for less than 200 m. Patients do notice difficulty standing on their toes and have slowing with variable calcaneal gait when walking fast. Forty-two percent of patients could run, 22% had pain in the donor site at rest, and 20% had pain when walking more than 200 m. Seventy percent had pain and weakness in the operated leg when attempting to run. Range-of-motion deficit existed in the operated limb, with average loss of 27% flexion and 14% extension.
The gracilis and sartorius muscles are not routinely used for pedicled reconstruction of the proximal tibia, nor would their harvest cause the symptoms of the patient described.
The reversed sural artery flap is an adipofascial flap that could be used for this described defect; however, its dissection does not jeopardize the common peroneal nerve.
The soleus muscle has better venous muscle pump function than the gastrocnemius, and edema, not nerve damage, is more common after use of the gastrocnemius. The limited data available suggest that the functional deficit with resulting limitation to ankle flexion is also more severe with soleus harvest.
A 60-year-old man sustains a Gustilo type IIIB open fracture of the distal left tibia during a boating accident. There is severe contamination of the wound, and the patient undergoes multiple formal washouts in the operating room. There is no neurovascular compromise of the extremity. He undergoes external fixation to stabilize the limb. Which of the following is the most appropriate next step in treatment?
A) Coverage with a free tissue transfer
B) Negative pressure wound therapy until secondary healing is achieved
C) Pedicled gastrocnemius muscle and skin grafting
D) Primary bone allografting
E) Split-thickness skin grafting
The correct response is Option A.
The Gustilo classification describes open fractures of the tibia by the severity of the soft tissue injury overlying the fracture. In patients with IIIB injuries, there is extensive soft-tissue loss and periosteal stripping, but no vascular compromise requiring repair.
Gustilo classification:
Type I: The wound is less than 1 cm long. There is little soft-tissue damage and no sign of crush injury. There is no or minimal comminution of the fracture.
Type II: The laceration is more than 1 cm long but there is no extensive soft tissue damage, flap, or avulsion. There is slight to moderate crushing injury, moderate comminution of the fracture.
Type III: Extensive damage to the soft tissues, including muscle, skin, and neurovascular structures, and a high degree of contamination.
Type IIIA: Soft tissue coverage of the bone is adequate.
Type IIIB: Extensive injury to or loss of soft tissue, with periosteal stripping and exposure of bone, massive contamination, and severe comminution of the fracture from high-velocity trauma
Type IIIC: Any open fracture with a vascular injury requiring repair.
Free tissue transfer will bring healthy, nontraumatized tissue into the area to cover the exposed broken bone. Multiple recent studies have shown equivalence of muscle versus skin/fat/fascia flaps for coverage of the open fracture even in patients with osteomyelitis. Negative pressure wound therapy has proven to be an excellent adjunct in the management of patients with these injuries. Between washouts, negative pressure devices can help decrease edema and isolate the wound and bone from the outside world. In a patient with a IIIB injury, there is insufficient tissue available to cover the wound. Therefore, secondary intention would not close the wound.
Split-thickness skin grafting provides an epithelial barrier to help seal off a wound from outside contamination. Grafts require a viable wound bed to survive. There must be a pliable bed to help grafts resist minor trauma in the future. With the periosteal stripping in this type of injury, a graft would not survive. In addition, graft placed directly on bone with periosteum would be very vulnerable to breakdown from minor trauma.
Bone allografting can be used to bridge defects in many circumstances. In the patient described, the severe contamination of the initial injury would make bone allografting much less appealing than autografting. Because of contamination, any type of bone grafting may need to be delayed until after achieving stable soft tissue coverage of the fracture.
A pedicled gastrocnemius muscle flap provides excellent coverage for defects about the knee, including the proximal tibia. Although the free gastrocnemius muscle flap could be transferred to any location, the pedicled flap would not be able to reach the distal tibia.
A 25-year-old man undergoes open reduction and internal fixation of a Gustilo Type IIIB tibia-fibula fracture. Coverage of the resultant soft-tissue defect with a free flap is planned. Which of the following is the ideal length of time after the injury that this procedure should be performed?
A ) 3 Days
B ) 10 Days
C ) 21 Days
D ) 60 Days
E ) 90 Days
The correct response is Option A.
Godina defined the timing of posttraumatic microsurgical lower extremity reconstruction in 1986 with recommendations for flap coverage of Gustilo Type IIIB/C fractures within 72 hours of injury. Godina’s study showed the highest risk of infection and flap loss in the delayed period (72 hours to 90 days). Subsequent authors have also cited lower rates of flap loss and infection when repair was performed.
Many authors have reported good flap survival when surgery is done within 3 days and 3 months after injury, but it is accepted that this delayed time frame necessitates more meticulous dissection and going well outside the zone of injury to a patent venous system to decrease the incidence of free flap loss.
Six months after undergoing plate fixation and primary wound closure for management of open fractures of the distal tibia and fibula sustained in a motorcycle accident, a 43-year-old man has purulent drainage from the wound site. Radiographs show bony nonunion at the fracture sites.
Which of the following is the most appropriate initial management?
(A) Continuous irrigation
(B) Debridement of bone
(C) Coverage with a muscle flap
(D) Bone grafting
(E) Insertion of an intramedullary rod
The correct response is Option B.
Osteomyelitis is a frequent complication of open fractures associated with soft-tissue injury, fibrosis, and localized ischemia. Measures to prevent the development of osteomyelitis, including removal of dead and devitalized bone, closure of dead space, and coverage with well-vascularized soft tissue, are recommended. In patients with established osteomyelitis, the most appropriate initial management is debridement of devascularized bone and necrotic or scarred tissues and removal of any nonautologous material, such as fixation devices. Because local soft tissue is frequently inadequate, free tissue transfer is often performed for soft-tissue coverage in the lower third of the leg. In patients who have unhealed fractures, an external fixation device is used to stabilize the fracture pattern. An Ilizarov frame may be applied if lengthening is required.
Continuous irrigation alone will not treat the osteomyelitis. Coverage with a well-vascularized muscle flap should be performed following bony debridement, and bone grafting should be delayed until the bone and soft tissues are stabilized and the osteomyelitis has resolved. Insertion of an intramedullary rod may further compromise bony perfusion.
An otherwise healthy 25-year-old man is evaluated because of footdrop and paresthesia 4 weeks after undergoing open reduction and internal fixation of a fracture of the proximal tibia. Electrodiagnostic testing shows no conduction of the nerve. Which of the following is the most appropriate next step in management?
A ) Ankle arthrodesis
B ) Peroneal nerve decompression
C ) Posterior tibial nerve decompression
D ) Posterior tibial tendon transfer
E ) Repeat electrodiagnostic testing in 4 weeks
The correct response is Option E.
Peroneal nerve palsy may lead to severe disability with footdrop and paresthesia. Traumatic peroneal palsy may result from supracondylar femoral fracture, knee dislocation, and proximal tibial fracture involving both motor and sensory changes. On examination, the motor deficit manifests as a footdrop, and the sensory deficit results in a loss of sensation along the dorsum of the foot. Unlike the loss of sensation associated with the peroneal nerve, the posterior tibial nerve is clinically morbid, as it is on the plantar aspect of the foot. The chronic injury may result in wounding of the plantar aspect of the foot, which may ultimately result in amputation.
Electrodiagnostic testing should be performed within 1 month of the injury to confirm sensory and motor deficits. In patients with partial nerve palsy, greater than 80% will recover completely and can be expected to recover with observation alone. A patient with complete palsy will have a much worse prognosis, with only 40% of patients with a functional recovery. If there is no neurologic improvement after 2 to 3 months, operative decompression should be performed. If the nerve is noted to be in continuity, and nerve action potentials are transmitted across a lesion, then there may be continuity of the nerve, and neurolysis is performed. If there is a transected nerve, a direct repair or nerve grafting may be performed.
When neurolysis and nerve grafting do not provide satisfactory results, the remaining surgical options are salvage procedures such as tendon transfer or arthrodesis. Posterior tibial tendon transfer is the most commonly used tendon transfer for this injury.
A 48-year-old man comes to the office because of drainage from the distal aspect of the wound 2 weeks after he underwent soft-tissue coverage with a free latissimus dorsi muscle flap for a degloving injury of the left lower extremity sustained in a motorcycle collision. Examination in the emergency department showed a Gustilo type IIIB tibia/fibula fracture and 6 cm of tibial loss. Debridement of the bone and stabilization with an external fixator were performed at the time of the injury. The patient underwent soft-tissue coverage 8 days after the injury. Examination today shows purulent drainage at the lower portion of the flap. Which of the following is the most likely cause of this complication?
A) Age of patient
B) Delay in soft-tissue coverage
C) Distal flap necrosis
D) Inadequate debridement
The correct response is Option D.
Posttraumatic reconstruction of the lower extremities with significant soft-tissue defects that expose bone, joints and tendons generally require free tissue transfer. The Gustilo-Anderson fracture classification system is widely used to describe the injury when associated with a long bone fracture. Gustilo type IIIB fractures are associated with periosteal stripping and exposure of bone with contamination. In 1986, Godina emphasized coverage of these soft-tissue defects within the first 72 hours of injury. Given the nature of these poly-trauma injuries, coverage of these wounds is not always possible in the given time frame. Staged debridement and negative pressure therapy have become common in the management of these injuries. Inadequate bone or soft-tissue debridement prior to reconstruction is a common cause of failure. The wound has to be free of all contaminants prior to reconstruction; thus, it is unlikely that an 8-day delay is the cause of breakdown. Distal flap necrosis would show more superficial breakdown and, in this case, is not the cause for a deep space infection. The patient’s age does not have any bearing on this complication.
A 33-year-old woman is brought to the emergency department after sustaining a 6 × 8-cm soft-tissue defect over the tibial tuberosity after being hit by a motor vehicle while riding her bicycle. Physical examination shows exposed bone at the proximal third of the leg. Which of the following muscle flaps is most appropriate for this patient?
A) Lateral gastrocnemius
B) Lateral soleus
C) Medial gastrocnemius
D) Medial soleus
E) Sartorius
The correct response is Option C.
The gastrocnemius is a powerful muscle in the superficial posterior compartment of the leg that acts to plantar flex the foot at the ankle joint and flex the leg at the knee joint. It is involved in standing, walking, running, and jumping.
The lateral head originates from the lateral condyle of the femur, while the medial head originates from the medial condyle of the femur. Its other end forms a common tendon with the soleus muscle; this tendon is known as the calcaneal tendon or ?Achilles tendon? and inserts onto the posterior surface of the calcaneus.The medial head is longer, and its muscular fibers extend more inferiorly. The gastrocnemius can be harvested as a muscular or musculocutaneous flap if the soleus is intact and plantar flexion of the foot will be preserved. Medial and lateral heads may be used independently based on the tissue defect present. Footdrop is possible with the use of the lateral muscle belly.The soleus is the other powerful muscle of the superficial posterior compartment of the leg. With the gastrocnemius, it acts to plantar flex the foot at the ankle joint. Specifically, the soleus plays an important role in standing; if not for its constant pull, the body would fall forward. The muscle originates from the posterior surfaces of the head of the fibula and its upper quarter, as well as the middle third of the medial border of the tibia. Its other end forms a common calcaneal tendon with the gastrocnemius muscle.The soleus muscle, when freed from its insertion on the Achilles tendon and based proximally, covers defects in the middle third of the tibia. It may also be used as a hemisoleus to cover distal third tibia defects as well.The sartorius flap may be raised as a muscle or myocutaneous flap based on segmental branches of the superficial femoral artery and vein. Because it has a Type IV segmental blood supply, the arc of rotation both superiorly and inferiorly is limited. Its best indication is for coverage of the femoral vessels.
An otherwise healthy 35-year-old man is brought to the emergency department after he collided with a parked bus while riding his motorcycle at 20 mph. On admission, he is cleared by the trauma service to undergo orthopedic exploration of an open fracture of the tibia and fibula. The surgeon achieves external fixation and begins washout of a 15-cm anterior wound with exposed denuded bone. A consultation regarding initial evaluation for soft-tissue coverage is requested. Which of the following additional findings is most likely to lead to the decision to recommend eventual below-the-knee amputation rather than reconstruction for this patient?
A) Gap of the tibial nerve of 4 cm
B) Grade 2 liver laceration
C) Ipsilateral full-thickness anterior plantar skin avulsion with associated metatarsal fractures
D) New-onset absence of the pulses in the foot following external fixation
E) Parietal contusion requiring endotracheal intubation and neurosurgical consultation
The correct response is Option A.
Avulsion of the tibial nerve is one of the two absolute indications for amputation in the context of Gustilo Type IIIB and IIIC open tibial fractures. This is because outcomes of microsurgical reconstruction of the insensate foot in these cases are very poor.
The other absolute contraindication to reconstruction is a warm ischemia time of 6 hours or greater, which the patient described does not have. The patient has just lost pulses after manipulation and fixation. This is a new finding, with very recent ischemia time. This is a potentially fixable situation, and not necessarily a contraindication to reconstruction. Recent loss of pulses could contribute to a need for amputation in the future but would not require that decision now.
Polytrauma, such as a liver laceration or an intracranial injury, can evolve into relative contraindications to reconstruction, but they are not absolute contraindications by themselves. The liver laceration could resolve and allow safe microsurgical reconstruction. Even the delay of time to reconstruction that polytrauma can necessitate can be managed with bony fixation, wound care, and vacuum-assisted closure placement until construction of a flap can be performed.
The loss of plantar skin and metatarsal fractures by themselves are also not an absolute contraindication to reconstruction. This is a potentially reconstructible problem that should not push the plastic surgeon to recommend amputation. The additional foot trauma can potentially be reconstructed either with a skin graft or a flap.
The intracranial injury can evolve to a point where neurosurgery would eventually release the patient for a free flap. So, the parietal contusion is not necessarily an absolute contraindication to reconstruction, depending on the eventual outcome from the head injury. The patient may very well get better from that, and become a limb salvage candidate. It all depends on severity.
Which of the following is the most likely cause of congenital constriction band syndrome of the lower extremity?
A) Defect in the zone of polarizing activity
B) Deletion of the gene responsible for the apical ectodermal ridge
C) Early amnion rupture
D) Exposure to retinoic acid
E) Use of thalidomide during pregnancy
The correct response is Option C.
Early amnion rupture with subsequent entanglement of fetal parts (mostly limbs and appendages) by amniotic strands is the primary theory of pathogenesis.
A wide spectrum of clinical deformities is encountered and range from simple ring constrictions to major visceral defects. Lower extremity limb malformations are extremely common and consist of asymmetric digital ring constrictions, distal atrophy, congenital intrauterine amputations, acrosyndactyly, lymphedema, and clubfoot.
Amniotic band syndrome is not a rare anomaly, as first described more than 150 years ago, and appears to be rising. Once believed to have an incidence of 1:100,000, recent literature supports the incidence today as 1:1200 to 1:5000 births.
No distinct sex predilection has been determined. Nearly 60% of the cases documented have some sort of abnormal gestation history. Prenatal risk factors associated with amniotic band syndrome include prematurity (less than 37 weeks), low birth weight (less than 2500 g), maternal illness during pregnancy, maternal drug exposure, and maternal hemorrhage. Attempted abortion in the first trimester is also a highly associated finding. Family history seldom shows any direct inheritance pattern since the syndrome occurs in no particular association with known genetic or chromosomal disorders.
The zone of polarizing activity signals the developing limb bud towards anterior/posterior polarity and does not result in truncation.
Proximodistal limb growth is the result of the apical ectodermal ridge. Deletion of the gene responsible for the apical ectodermal ridge will result in shortening of the limb but not in congenital constriction band syndrome. Experiments in which the apical ectodermal ridge has been removed show truncated limb growth. Scientific evidence supports that the pattern of limb anomalies in the offspring of mothers exposed to exogenous retinoids, such as retinoic acid, causes interference with apical ectodermal ridge function, resulting in similar deformities.
Thalidomide results in various limb deformities, including phocomelia, dysmelia, amelia, and bone hypoplasticity, with as little as a single dose of thalidomide during gestation. It does not, however, result in constriction bands. It is postulated that thalidomide-associated malformations are the result of the drug’s interference with vasculogensis.
A 46-year-old woman presents with new-onset pain following below knee amputation. Medical history includes a Gustilo IIIB left leg injury and failed limb salvage 3 years ago. The patient reports phantom sensation, pain in her great toe, burning that ascends the limb, and several points along the distal stump that are inappropriately tender.On examination, a well - healed amputation stump without evidence of unstable skin or skin changes consistent with pressure - related trauma is noted.Targeted muscle reinnervation surgery is planned. Which of the following is the most likely evolution of neuropathic pain at 4 weeks and 6 months postoperatively in this patient?
The correct response is Option C.
Targeted muscle reinnervation (TMR), as originally described by Dumanian and Kuiken, is a procedure in which sensory and/or mixed nerves are transferred or coapted to motor nerve branches, in an effort to promote organized nerve growth and also to improve prosthetic control. While initially explored for improvement of prosthetic functionality, researchers observed a concomitant reduction in neuropathic and residual limb pain.
Though more research is needed, targeted muscle reinnervation may be most successful in decreasing or preventing pain when performed at the time of the amputation. The natural history of pain following TMR performed secondarily (not at the time amputation) includes a period of immediate relief (nerves are cut proximal to the neuroma), followed by activation of the nerves and increased pain (3 to 6 weeks), and plateau and reduction of pain (6 weeks to 6 months).
Nearly all patients report a decrease in pain and improvement in quality of life. The degree with which the pain is decreased and life is improved may be related to the timing of the operation. Data suggest that the earlier the operation is performed, the better the results, perhaps because of the centralization of the somatic pain response, though more work is needed to elucidate this mechanism.
A 56-year-old woman with a traumatic defect of the upper third of the tibia undergoes open reduction and internal fixation with tibial nail. Soft tissue coverage with a gastrocnemius flap is planned. Which of the following arteries provides the dominant blood supply for this flap?
A) Anterior tibial
B) Peroneal
C) Popliteal
D) Posterior tibial
E) Sural
The correct response is Option E.
Each head of the gastrocnemius muscle is supplied by the sural artery: either the medial sural or lateral sural artery for medial and lateral gastrocnemius, respectively. The arteries arise from the popliteal artery about 3-4 cm above the head of the fibula and enter the medial and lateral heads of the gastrocnemius at about the level of the head of the fibula. The flap can be rotated to cover soft-tissue defects of the anterior distal aspect of the knee. The flap ranges from 5 to 9 cm in width and from 13 to 20 cm in length. It provides a vascular bed for a skin graft and improves the delivery of oxygen and systemic antibiotics. The other listed arteries do not supply the gastrocnemius muscles.
A 30-year-old man is scheduled to undergo great toe-to-thumb transfer 7 months after traumatic amputation of the dominant thumb. During dissection of the toe, the first dorsal metatarsal artery is most likely to be found branching from which of the following vessels?
A) Deep plantar
B) Dorsalis pedis
C) Plantar arterial arch
D) Posterior tibial
E) Proper digital
The correct response is Option B.
The origin and course of the first dorsal metatarsal artery (FDMA) are key to dissecting the first or second toe and the variety of available toe flaps. This anatomy is quite variable. In two thirds of cases, this artery emanates from the dorsalis pedis artery as its distal continuation. This course can then be superficial, within, or deep to the interosseous muscle. However, in one third of patients, the metatarsal artery may arise from the deep plantar artery that communicates with the plantar arch or actually from the plantar arch itself, in which case the FDMA may be vestigial. In the latter two situations, the metatarsal artery passes plantar to the deep transverse metatarsal ligament. The proper digital arteries are the distal continuations of the FDMA. The posterior tibial artery runs longitudinally in a superficial plane to the forefoot on the plantar surface. It is the larger lateral plantar artery that travels deeply to become the plantar arterial arch.
A 15-year-old girl sustained an isolated open tibial fracture in a motor vehicle collision. At the proximal third of the tibia, 15 cm of anterior soft-tissue loss is noted. Despite fracture reduction, the foot is warm but pulseless without dopplerable signals. The patient is otherwise stable. Which of the following is the most appropriate next step in management?
A) Below-knee amputation
B) CT angiography
C) Four-compartment fasciotomy
D) Internal fixation and soft-tissue coverage
E) Surgical exploration of the popliteal artery
The correct answer is option B.
Lower extremity fractures with combined soft-tissue and neurovascular trauma have high rates of complications, and a percentage of these injuries lead to amputation. Risk factors for amputation include Gustilo IIIC injuries, sciatic or tibial nerve injuries, prolonged ischemia (more than 4 to 6 hours), significant soft-tissue injury, significant wound contamination, multiple injured extremities, advanced age, lower versus upper extremity trauma, and futile attempt at revascularization. While tibial nerve injury is a risk factor and relative indication for amputation, it is never an absolute indication for amputation. Hard signs for vascular injury include: active hemorrhage, expanding hematoma, bruit or thrill, absent distal pulses, and distal ischemic signs and symptoms (five P’s). In the face of these hard signs, imaging such as CT angiography should be used to evaluate for vascular injury. With that said, most hard signs can be explained by soft-tissue or bone bleeding, traction of intact arteries due to unreduced fractures, or compartment syndrome. Early soft-tissue coverage is associated with a lower complication rate. The goal is to close wounds within 7 to 10 days to decrease the risk for infection, osteomyelitis, nonunion, and further tissue loss. It is best to get wound control prior to bone grafting, avoiding the risk of losing valuable limited bone; therefore, bone grafting is generally postponed until 8 to 10 weeks after soft-tissue wound coverage.
A 50-year-old man has noninfected wound dehiscence with exposure of the hardware two weeks after undergoing open reduction and internal fixation of an ankle fracture. A photograph and radiograph are shown above. Following debridement of the wound, which of the following is the most appropriate management?
(A) Skin grafting
(B) Coverage with a free flap
(C) Application of an external fixator and skin grafting
(D) Removal of the hardware and skin grafting
(E) Removal of the hardware and coverage with a free flap
The correct response is Option B.
This patient has early wound dehiscence after undergoing open reduction and internal fixation of a lateral malleolus fracture. Appropriate management involves early coverage of the exposed bone and hardware to promote bony union while preventing bacterial colonization of the hardware, which may lead to the development of osteomyelitis. Because this patient underwent open reduction and internal fixation only two weeks ago, fixation is still required to maintain rigid fracture stabilization. Instead, coverage with a free flap is recommended to provide stability and vascularity and to enhance function once bony union is obtained.
Skin grafting will not provide stable, well vascularized coverage in this patient. External fixation is problematic because of the location of the fracture. Removal of the hardware two weeks after fracture is indicated only for established hardware failure.
A 15-year-old boy is brought to the emergency department 1 hour after his left foot was severed when his leg was run over by a train. Photographs are shown. Which of the following is the most appropriate management?
A ) Construction of a foot filet free flap
B ) Replantation and ankle fusion
C ) Revision amputation to the level of the skin edge and primary closure
D ) Split-thickness skin grafting
E ) Temporary revascularization with shunts and delayed replantation
The correct response is Option C.
The patient described has a limb amputation that includes a significant avulsion component, exemplified in the long tendon stumps that appear ripped off from their muscle bellies, and ankle disarticulation. Avulsion amputations of the lower extremity are not suitable for replantation because of the extended neurovascular damage that is present on both ends well beyond the level of the injury. The incidence of thrombosis at the anastomosis is high. Use of vein grafts on a free flap could be considered, but, in this case, they may have to be connected as high as knee level to ensure patency. The amputated part likely has massive microscopic endothelial damage extending to terminal vessels and could only be used as a donor site for skin grafts. Therefore, there is no role for immediate or delayed replantation.
While preservation of maximum tibial length is desirable in preparing the amputation stump, prosthetic fitting for ankle disarticulations is fraught with trouble. Some tibial shortening is required to have a comfortable, reliable prosthesis. In the scenario described, tibial shortening of 2 and 4 in would have equivalent results because there is still ample length of proximal tibia
available to provide the same functionality and equivalent energy expenditure. Therefore, use of a free flap to protect an additional 2 in of tibia adds no advantage for this patient. When the level of amputation is through the proximal tibia, some benefit could be found in that a minimum of 6 in of proximal tibia is available for prosthetic fitting. Split-skin grafts are generally unstable in weight-bearing surfaces and take longer to heal and mature, which causes delay in rehabilitation. Skin grafts will not take or perform well when applied over an articular surface.
A 35-year-old man is referred to the office after undergoing prolonged failed attempts at local wound care of an exposed Achilles tendon. Physical examination shows that the tendon is beginning to desiccate. Coverage with a flap is performed, as shown. The blood supply to this flap is derived from which of the following arteries?
A) Anterior tibial
B) Geniculate
C) Peroneal
D) Popliteal
E) Superficial femoral
The correct response is Option C.
The flap used to cover the Achilles tendon in the patient described is the reverse sural fasciocutaneous flap. It is based on perforators from the peroneal artery through a network of small vessels. The general axis of the flap follows the sural nerve from behind the lateral malleolus to the mid portion of the gastrocnemius muscle bellies. Sural nerve injury results in loss of lateral foot sensation. This is often of no functional consequence because its harvest does not result in loss of a major neurovascular structure.
The other vessels noted do not supply inflow to the flap.
A 20-year-old man has purulent breakdown 5 months after sustaining a Gustilo type IIIB open fracture treated with intramedullary rod placement and skin grafting over a medial gastrocnemius flap. A postoperative x-ray study and current photograph are shown. The intramedullary rod is removed and an external fixator is placed. There is 1.5 cm of bone without periosteum surrounding the fracture exposed in the wound. Which of the following is the most appropriate next step in wound reconstruction?
A) Full-thickness skin grafting with a bolster dressing
B) Reconstruction with an anterior tibial artery perforator flap
C) Reconstruction with a lateral gastrocnemius muscle flap and skin grafting
D) Reconstruction with a pedicled descending medial genicular artery flap
E) Split-thickness skin grafting with negative pressure wound therapy
The correct response is Option B.
Perforator flap reconstruction, whether free or pedicled, has become increasingly popular over the past decade. Perforator flap use allows for the creation of an axial pattern flap without the sacrifice of a major artery and can often be done for areas once considered to require free flaps for coverage. Prior transfer of a medial gastrocnemius flap might disrupt perforators from the posterior tibial artery to the medial leg skin, but would not have disturbed anterior tibial artery perforators through the skin of the anterolateral leg.
Skin grafting, whether split- or full-thickness, would not be successful on fractured bone without periosteum, regardless of the type of dressing used.
The lateral gastrocnemius muscle is smaller and cannot reach as far as the medial gastrocnemius. It would not be able to reach the mid-shaft tibia defect shown in this patient.
The descending medial genicular artery is the pedicle of the medial femoral condyle flap. It is normally used as a bone graft donor, although an overlying skin paddle can be harvested with it. When used in a pedicled fashion, it can be transposed proximally onto the thigh, but not distally onto the leg.
A 57-year-old man comes to the office 4 weeks after undergoing a free osseocutaneous fibula flap. He says he has pain with walking. A photograph is shown. X-ray studies show 6 cm of fibular bone remains proximally and distally. Sensation of the right foot shows no abnormalities; pain is noted on plantar flexion. Which of the following is the most appropriate next step in management?
A) Cast immobilization of the lower extremity (above the knee)
B) Cast immobilization of the lower extremity (below the knee)
C) Operative exploration and bone grafting
D) Operative exploration and nerve grafting
E) Reassurance that the pain is self-limiting
The correct response is Option E.
Vascularized bone flap is typically needed for defects >6 cm regardless of location in the body. The fibula is a common donor for vascularized bone. Understanding the postoperative course and complications is needed both in terms of discussions with the patient preoperatively and management of the patient’s condition after surgery. Common sequelae of fibula harvest include pain in the leg (especially when walking). Four weeks is relatively early in the postoperative course and reassurance should be given.
Risks of fibula harvest include damage to the peroneal nerve (increased when <6 cm of bone is left behind or when the head of the fibula is included in the harvest); destabilization of the ankle (increased when <6 cm of bone is left behind); and damage to the posterior tibial nerve.
A free-fibular flap design with hash marks left intact is shown.
Which of the following anatomic structures is an important landmark in raising a reverse sural artery flap?
A) Achilles tendon
B) Deep peroneal nerve
C) Lesser saphenous vein
D) Plantaris tendon
E) Posterior tibial artery
Correct answer is option C.
When raising a reverse sural artery flap, the important landmarks are the lesser saphenous vein and sural nerve, which should bisect the cutaneous paddle. The blood supply to this flap depends on the medial superficial sural artery and the lesser saphenous vein with its two small accompanying arteries. The pivot point of the pedicle is typically 5 cm above the lateral malleolus, where the perforators of the flap enter a more superficial plane.
The Achilles tendons are not landmarks for raising this flap but, when exposed, are good indications for this type of flap. The deep peroneal nerve is located in the lateral compartment. The posterior tibial artery is found in the deep compartment and is not associated with this flap. The plantaris tendon is deep to the dissection of the flap.
Which of the following is the most common primary arterial blood supply to the great toe flap used in toe-to-thumb transfer?
A) First dorsal metatarsal artery from the communicating branch between the dorsalis pedis and plantar arteries
B) First dorsal metatarsal artery from the plantar arch
C) Second dorsal metatarsal artery from the dorsalis pedis artery
D) Second dorsal metatarsal artery from the plantar arch
The first dorsal metatarsal artery (FDMA), arising from the dorsalis pedis artery, is the most common primary arterial blood supply to the great toe flap, which is used in toe-to-thumb transfer. Although the vascular anatomy that supplies the great toe flap is somewhat variable, the FDMA typically arises from the dorsalis pedis artery and travels in a relatively dorsal plane. It may travel dorsal or plantar to the interosseous muscle or through the muscle itself.
The FDMA is less likely to arise from the communicating branch between the dorsalis pedis and plantar arteries or from the plantar arch.
The second dorsal metatarsal artery does not contribute to the great toe flap.
A 62-year-old man is scheduled to undergo reconstruction of a 7-cm bone defect (shown) resulting from excision of a tumor of the distal radius. He has hypertension and has smoked one pack of cigarettes daily for 30 years. Which of the following is the most appropriate technique for reconstruction of the defect?
A ) Allograft bone graft
B ) Fibula free flap
C ) Locking fixation plate
D ) Pedicled ulna bone flap
The correct response is Option B.
Composite tissue reconstruction after tumor ablation is a significant challenge to the plastic surgeon. Generally, bony defects greater than 6 cm require vascularized bone for reconstruction. For large defects, the optimum choice of bone is the vascularized fibula. The fibula also has a reliable blood supply from the peroneal artery and can be harvested with a cutaneous skin paddle. The fibula free flap is the most appropriate technique. Reconstruction with free flaps can be successfully performed in a patient with a smoking history and, in fact, is often the optimal method of reconstruction in smokers. The use of allograft cadaver bone is not indicated, especially in a patient with a history of smoking. For defects of the size shown in the photograph, the locking fixation plate would not give adequate long-term support. A local bone flap is also not a viable option.
A 24-year-old man is brought by ambulance to the emergency department after sustaining a tibial fracture in a motorcycle collision. On physical examination, there is an open, segmental fracture with a 4-cm wound and a large avulsion flap, but adequate soft-tissue coverage. Which of the following Gustilo-Anderson fracture classifications best describes this injury?
A) Type I
B) Type II
C) Type IIIA
D) Type IIIB
E) Type IIIC
The correct response is Option C.
is restored after 6 hours from the time of injury. On examination, the foot is cold, and no plantar sensation is noted. The posterior tibial nerve is disrupted. A temporary external fixator is placed. A photograph and an x-ray study are shown. Which of the following is the most appropriate classification of this injury and recommendation for management?
A) Gustilo type IIIB; amputation
B) Gustilo type IIIB; reconstruction
C) Gustilo type IIIC; amputation
D) Gustilo type IIIC; reconstruction
The correct response is Option C.
The patient described has a Gustilo IIIC injury. Based on the best available data, he should undergo amputation.
Ultimately, the choice to reconstruct versus amputate is a gestalt of the situation and the patient, as well as the capabilities of the hospital and the care team. In this case, the factors influencing the decision would be the warm ischemia time of 6 hours and severed posterior tibial nerve, as well as the extensive soft-tissue injury.
Some of the newer data suggests that absence of plantar sensation is no longer criteria for amputation in and of itself. However, an anatomically disrupted nerve in an adult strongly favors amputation.
In addition, there is evidence supporting the notion that limb salvage might involve less cost in the long term versus reconstruction.
Gustilo Classification
I: open fracture; clean; wound less than 1 cm
II: open fracture; wound greater than 1 cm
IIIA: open fracture; extensive soft-tissue injury but adequate tissue for coverage
IIIB: open fracture; extensive soft-tissue injury but inadequate tissue for coverage
IIIC: any of the above with a vascular (arterial) injury
A 34-year-old man who works as a police officer is brought to the emergency department after sustaining a traumatic avulsion of the right heel. Examination shows a 3 * 3-cm area of exposed calcaneus on the weight-bearing aspect of the heel. Which of the following arteries and nerves supply the flap that will provide the most appropriate sensate coverage?
The correct response is Option B.
Sensate flaps include an intact sensory nerve supplying the overlying skin being transferred or, as in the case of a free tissue transfer, the cutaneous nerve is preserved and reanastomosed to a recipient cutaneous nerve. Sensate flaps are useful for areas where sensation is important for the appropriate function of a reconstructed region. Sensate flaps are beneficial in resurfacing wounds located on weight-bearing areas as in pressure sores or the heel, as in the scenario described.
The most reliable sensate flap for coverage of the plantar calcaneus comes from the medial plantar flap. This flap receives its sensation from the medial plantar nerve (L4-5) and receives its blood supply from the medal plantar artery. This flap comes from the instep of the foot between the head of the first metacarpal and the midpoint of the heel. The size of the flap can be up to 12 * 6 cm. Due to its proximity to the heel and the minimal donor morbidity with loss of sensation to the instep of the foot, this flap is the most appropriate for coverage of this patient €™s defect.
The dorsalis pedis flap receives its blood supply from the dorsalis pedis artery. This flap can be transferred as a sensate flap using the superficial peroneal nerve. However, this flap would not reach the area needed to be covered in this patient. The dorsalis pedis flap is used most frequently for coverage of the anterior ankle and dorsal distal foot.
The medial sural artery supplies the medial gastrocnemius flap. This flap is best used for soft-tissue coverage of the upper third of the leg and the distal knee. Preservation of the saphenous nerve with the medial gastrocnemius musculocutaneous flap will provide a neurosensory flap.
However, due to the distance from the flap, it would require a free tissue transfer and is typically not used for this type of coverage.
The proximal branches of the posterior tibial artery supply the medial soleus muscle flap. The posterior tibial nerve supplies only motor fibers to the soleus muscle and can therefore not be used as a sensate flap. This flap is best used for soft-tissue coverage of the middle third of the leg.
The radial forearm flap receives its blood supply from the radial artery and its septocutaneous perforating vessels. A neurosensory flap can be harvested based on the medial or lateral antebrachial cutaneous nerves to reconstruct the plantar surface of the foot. This would be a second choice to the medial plantar artery flap as it requires free tissue transfer.
A 38-year-old man comes to the office for follow-up examination two months after undergoing open reduction and internal fixation of a fracture of the right proximal fibula. A preoperative radiograph is shown. On current physical examination, he can evert the right foot, but he is unable to dorsiflex it. This patient has most likely sustained an injury to which of the following nerves?
A ) Common peroneal B ) Deep peroneal C ) Sciatic D ) Superficial peroneal E ) Sural
The correct response is Option B.
The patient described has sustained an injury to his deep peroneal nerve. An electromyelogram should be ordered to confirm the diagnosis. The common peroneal nerve divides into two branches. The deep branch of the peroneal nerve innervates the extensor hallucis longus and the anterior tibial muscles. The superficial branch of the peroneal nerve provides motor innervation to the peroneus longus and brevis muscles. If the common peroneal nerve had been injured, eversion would not have been likely. A sural nerve injury would have a sensory component, not a motor component. The sciatic nerve injury would have more global consequences, though this pattern is theoretically possible in a Sunderland Grade VI injury. Thus, the most likely injured nerve is the deep peroneal nerve.
A 58-year-old man comes to the office for follow-up 3 weeks after undergoing mandibular reconstruction with a fibular free flap. The patient reports numbness of the operated extremity and says he has difficulty walking. Which of the following sensory and motor deficits is most likely in this patient?
The correct response is Option A.
The injury in the patient described is to the common peroneal nerve.
Both the first web space of the foot and the extensor hallucis longus and tibialis anterior muscles are innervated by branches of the common peroneal nerve. The finding of absence of sensation over the medial aspect of the calf and weakness of the soleus and extensor digitorum brevis muscles is eliminated by numbness of the medial calf, which is innervated by the saphenous nerve, a branch of the femoral nerve. Absence of sensation over the medial malleolus and heel with weakness of the soleus and tibialis anterior muscles is eliminated by numbness of the medial malleolus, which is also innervated by the saphenous nerve. In addition, the soleus is innervated by the tibial nerve. The finding of absence of sensation in the third web space of the foot and weakness of the soleus and extensor digitorum brevis muscles is eliminated by the soleus muscle. The finding of absence of sensation over the upper lateral calf and weakness of the flexor hallucis longus and extensor digitorum brevis muscles is eliminated by the flexor hallucis longus, which is innervated by the tibial nerve.
A 48-year-old man presents to the emergency department because of spontaneous progressive pain, swelling, cyanosis, and edema of the left lower extremity for the past 24 hours. A photograph is shown. Medical history includes prophylactic inferior vena cava (IVC) filter placement in the setting of prolonged immobilization secondary to traumatic closed head injury sustained 2 years ago. Physical examination shows no dyspnea. Oxygen saturation is 98% on room air. Venous ultrasonography and CT scan show total left deep femoral thrombosis extending into the lower IVC at the indwelling filter. Which of the following is the most appropriate next step in management?
A) Catheter-directed thrombolysis
B) Femoral vein to IVC vascular bypass
C) Isolated extracorporeal membrane oxygenation (ECMO) support to the affected extremity
D) Open thrombectomy
E) Oral anticoagulation
The correct response is Option A.
The patient is presenting with extensive acute thrombotic occlusion resulting in clinically evident symptomatic venous insufficiency of the extremity. If the occlusion is left untreated, progressive cyanosis and secondary ischemia followed by gangrene develop. Locally delivered thrombolytic agents via catheter-directed thrombolysis with or without percutaneous transluminal angioplasty is an effective first line of treatment in this scenario where the patient presents within a few days of symptom onset (ie, prior to clot fibrosis) and is not high-risk for bleeding. In patients who are high-risk for bleeding (eg, acute intracerebral hemorrhage, gastrointestinal bleeding), alternative methods of restoring venous outflow include clot retrieval through other percutaneous or open techniques (eg, transluminal aspiration thrombectomy, open inferior vena cava (IVC) thrombectomy with or without temporizing groin arteriovenous fistula creation). Systemic thrombolysis can be considered when other first line therapies are not available but has been associated with high frequency of major bleeding complications in several randomized trials (14% for streptokinase).
Systemic anticoagulation infusion helps prevent progression but does not restore acute compromised ischemic limb secondary to venous outflow obstruction. Oral anticoagulation is not indicated for acute management of a limb-threatening thrombosis. Femoral vein to IVC vascular bypass is not a described procedure for venous insufficiency. Limb-threatening thrombo-occlusive venous insufficiency resulting in a painful swollen blue leg, such as that pictured (also known as “phlegmasia cerulea dolens,” literally “painful blue edema”) was first described with heparin-induced thrombocytopenia. It has also been associated with cancer or life-threatening critical illness. More recently, a growing population of patients are at risk due to unretrieved IVC filters. While IVC filter placement may protect the pulmonary vascular bed, it does not lessen thrombotic predisposition or incidence in the lower extremities, and IVC thrombosis with or without phlegmasia cerulea dolens has been reported to occur in 3 to 30% of patients following IVC filter placement. Filter retrieval following its initial indicated need can lessen secondary thrombotic complications, but data suggest that only a fraction of retrievable filters are later removed. In a systemic review, overall retrieval was 34% with a high percentage of nonretrieval occurring for a variety of reasons, including loss to follow up (particularly in trauma centers), limited life expectancy, and/or unresolved underlying conditions.
An otherwise healthy 47-year-old man is transferred to the hospital because of an infection of the leg. He sustained the initial injury in a fall 6 weeks ago that was treated with internal fixation. The infection is now under control, and the internal hardware has been removed. Examination shows a 9-cm bony defect of the lower extremity. Neurovascular status of the foot is normal. Angiography of both lower extremities shows no abnormalities. A photograph and x-ray study are shown. Which of the following considerations favors vascularized bone grafting in this patient?
A) Length of time since the initial injury
B) Mechanism of the injury
C) Method of injury stabilization
D) Patient age
E) Size of the bony defect
The correct response is Option E.
The injury described is a Gustilo IIIB lower extremity wound complicated by infection. The sequence of reconstruction is often bony stabilization and debridement until bacterial balance. Bony deficits can be reconstructed in a variety of ways, including non-vascularized grafts, vascularized grafts (free of pedicle), and bone transport.
Generally, for defects greater than 6 to 8 cm, vascularized bone grafting is indicated.
Other indications for vascularized bone grafting are the presence of infection and prior failure of conventional (non-vascularized) grafting.
Age of the patient is not a contraindication to reconstruction per se, as long as he or she is medically stable to undergo a prolonged operation.
Gustilo Classification
I: open fracture; clean; wound less than 1 cm
II: open fracture; wound greater than 1 cm
IIIA: open fracture; extensive soft-tissue injury but adequate tissue for coverage
IIIB: open fracture; extensive soft-tissue injury but inadequate tissue for coverage
IIIC: any of the above with a vascular (arterial) injury
A 36-year-old man is evaluated for coverage of a 4 × 3-cm middle-third lower extremity soft-tissue defect with an exposed fracture of the mid tibia. Reconstruction with a proximally based medial hemisoleus muscle flap is planned. Which of the following arteries provides the major contribution to the blood supply of this flap?
A) Anterior tibial
B) Dorsalis pedis
C) Medial sural
D) Peroneal
E) Posterior tibial
The correct response is Option E.
The soleus muscle is a bipennate muscle that is located in the superficial posterior compartment of the lower extremity, deep to the gastrocnemius muscle. The soleus muscle has a medial head that originates from the posterior aspect of the tibia and a lateral head that originates from the posterior surface of the fibula. The soleus functions in plantar flexion of the foot in conjunction with the gastrocnemius as they unite to form the Achilles tendon. Branches from the popliteal artery contribute to the blood supply of the proximal soleus muscle.
The soleus muscle flap is a reliable local flap for coverage of moderate-sized soft tissue defects of the middle-third of the lower extremity. It is customarily elevated as a muscle-only flap and covered with a split-thickness skin graft. Branches from the posterior tibial artery contribute to the blood supply of the medial hemisoleus muscle flap, which is more reliable when based proximally.
Branches from the peroneal artery contribute to the blood supply of the lateral hemisoleus muscle.
The medial sural artery is the dominant blood supply to the medial gastrocnemius muscle flap.
The anterior tibial artery and the dorsalis pedis artery do not contribute to the blood supply of the medial hemisoleus flap
A 40-year-old woman is referred by her orthopedic surgeon for reconstruction because of an exquisitely tender scar over the site of the anterolateral portal for arthroscopy of the left ankle. Examination shows a 1-cm scar over the lateral malleolus. Tinel sign is present over the scar. Sensation is diminished over the middle part of the dorsum of the foot. Which of the following nerves is most likely to have been injured during the arthroscopy?
A) Lateral malleolar
B) Medial plantar
C) Saphenous
D) Superficial peroneal
E) Sural
The correct response is Option D.
In the patient described, the dermatomal distribution of numbness of the middle of the dorsum of the foot suggests injury of the superficial peroneal nerve (SPN). The SPN supplies the sensation to the middle portion of the dorsum of the foot, except for the skin in the great toe web space (which is innervated by the deep peroneal nerve). The lateral malleolar nerve is a terminal branch nerve supplying the skin of the lateral malleolus. The medial plantar nerve supplies the medial three fourths of the plantar surface of the foot. The saphenous nerve travels to the dorsum of the foot, medial malleolus, and the area of the head of the first metatarsal. At the level of the ankle, the saphenous nerve is found between the medial malleolus and the anterior tibial tendon, just lateral to the saphenous vein. The sural nerve is located at an average of 7 mm posterior to the lateral malleolus and supplies sensation to the lateral aspect of the foot. A diagram is shown.
According to one study, in ankle arthroscopy the risk of SPN injury is maximal in the 0 to 3 mm lateral to the peroneus tertius tendon. To avoid injury to the SPN, the safest placement of the anterolateral portal is 4 mm lateral to the peroneus tertius tendon.
In another study, in 82% of specimens, the SPN ran between the lateral border of the talocrural joint and the peroneus tertius tendon at the talocrural joint level, where the anterolateral portal was placed. Therefore, the SPN was at high risk for injury with anterolateral portal placement.
A 28-year-old man has a markedly diminished dorsalis pedis pulse on the right after being stabbed with an ice pick in the right lower leg. In this patient, the most likely finding on physical examination is numbness at which of the following sites?
A) Dorsal foot
B) First web space
C) Lateral foot
D) Medial foot
E) Plantar foot
The correct answer is option B.
This 28-year-old man has a markedly diminished dorsalis pedis pulse after sustaining a laceration of the anterior tibial artery when he was stabbed in the leg. Therefore, he is most likely to have numbness of the first web space of the foot on physical examination. The first web space is innervated by the deep peroneal nerve; this nerve courses within the anterior compartment of the leg with the anterior tibial artery, which becomes the dorsalis pedis artery in the foot.
-The dorsal aspect of the foot (with the exception of the first web space) is innervated by the superficial peroneal nerve.
-The lateral foot is innervated by the sural nerve, and the medial foot is innervated by the saphenous nerve. None of these nerves travels with an artery.
The plantar surface of the foot is innervated by the tibial nerve, which courses within the deep posterior compartment of the leg with the posterior tibial artery.
A 32-year-old male is brought to the emergency department following a high-speed motor vehicle collision. The patient reports severe pain and deformity of the left lower extremity. Physical examination reveals an obvious dislocation at the proximal tibiofibular joint and significant swelling around the knee. The patient has diminished capillary refill in the foot but intact posterior tibial and dorsalis pedis pulses. Neurologic examination reveals complete anesthesia in the first dorsal webspace of the foot and weakness in dorsiflexion of the foot and toes. The affected limb demonstrates a valgus deformity, and radiographs confirm a traumatic proximal tibiofibular fracture-dislocation. Based on the patient’s clinical findings, which nerve is most likely injured?
A) Tibial nerve
B) Sural nerve
C) Saphenous nerve
D) Sciatic nerve
E) Common peroneal nerve
Correct Answer: E) Common peroneal nerve
Rationale:
Traumatic proximal tibiofibular dislocations frequently lead to injury of the common peroneal nerve, which courses around the fibular head, making it particularly susceptible to injury in these cases. Neurologic symptoms often include sensory deficits in the first dorsal webspace (innervated by the deep peroneal nerve) and foot drop due to weakness in dorsiflexion and toe extension.
The other options are incorrect:
• Tibial nerve: Responsible for plantarflexion and sensation to the sole of the foot; its injury would not result in first webspace anesthesia.
• Sural nerve: Provides sensation to the lateral aspect of the foot and ankle, not the first webspace.
• Saphenous nerve: A sensory nerve that supplies the medial aspect of the leg and ankle.
• Sciatic nerve: Typically causes widespread motor and sensory deficits in the lower limb, rather than isolated first webspace anesthesia.
Traumatic proximal tibiofibular fracture-dislocation injuries can be
severe, sometimes needing immediate surgical intervention.
Especially in cases with open fractures, vascular injury and
compartment syndrome have been reported, with compartment
syndrome being seen in 29% of cases in one study. Most larger case
series also report variable rates of amputation, whether for a
nonreconstructable limb, vascular injury, or nerve dysfunction.
Common peroneal nerve injury is the most commonly reported
nerve injury, sometimes involving greater than 35% of cases. As
such, residual peroneal nerve deficits are the most common reason
for later nerve reconstruction surgery. Posterior tibialis tendon
transfer is a common option for common peroneal nerve
dysfunction-related footdrop.
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proximal tibiofibular dislocation: a marker of
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2. Rajan PV, Ramski DE, Romeo NM. Traumatic
dislocation of the proximal tibiofibular joint: a
systematic review and 10-year experience from a
level 1 trauma center. J Am Acad Orthop Surg Glob
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