Soft tissue Flashcards
What Z-plasty angle provides approximately 50% scar lengthening?
45 degrees. A 45° angle achieves roughly 50% lengthening, with each additional 15° increment adding about 25% more length (e.g., 60° achieves ~75%).
If you need 100% lengthening in a scar contracture via Z-plasty, what limb angle should you choose?
75 degrees.
According to Z-plasty principles, a 75° angle results in approximately 100% increase in scar length.
How much lengthening would a 60-degree angle achieve in a Z-plasty?
**About 75%.
**
Each incremental 15° increase from 30° adds roughly 25% additional lengthening
30° = 25%,
45° = 50%,
60° = 75%
75° = 100%.
Presence of fibrinous “rice bodies” in the wrist tenosynovium strongly suggests which diagnosis?
**Tuberculosis.
**Rice bodies are characteristic fibrinous formations commonly seen in chronic tenosynovial tuberculosis.
In a patient with chronic wrist swelling and carpal tunnel syndrome, finding fibrinous loose bodies intraoperatively should prompt suspicion of what atypical cause?
Tuberculous tenosynovitis.
This form of extrapulmonary tuberculosis often presents with fibrinous “rice bodies” and atypical carpal tunnel symptoms.
How might tuberculous tenosynovitis clinically present in the hand?
It commonly presents as a chronic compound palmar ganglion or wrist swelling, carpal tunnel symptoms, and characteristic intraoperative fibrinous rice bodies.
Why does a full-thickness skin graft generally have lower initial take rates than a split-thickness graft?
It includes the full dermis, making revascularization slower due to less superficial vascularity, necessitating ideal graft bed conditions.
True or False: A split-thickness graft donor site heals faster when thinner grafts are harvested.
True. Thinner grafts, harvested superficially with a high density of tiny bleeding points, heal faster than deeper, thicker graft harvests.
Can a skin graft survive on bare cortical bone, tendon, or cartilage?
Yes, but only via bridging. Small grafts may survive initially through bridging, where nutrients diffuse through a fibrin clot until neovascularization occurs.
What is the most reliable reconstructive option for a large dorsal hand defect with exposed tendons, joints, and bone following trauma?
A pedicled reversed radial forearm flap provides robust and reliable vascularized tissue coverage for extensive dorsal hand defects.
One possible option
Why is a negative pressure dressing alone inappropriate directly on exposed tendons without paratenon coverage?
Direct negative pressure dressings on denuded tendons cause desiccation, impairing future graft take and tendon viability.
Why might a bilayer dermal regeneration template (Integra®) be suboptimal for large contaminated dorsal hand defects with exposed structures?
Dermal templates require granulation tissue formation, are slow, infection-prone, and often fail in large contaminated wounds with exposed joints or bone.
According to Mathes and Nahai, into which category does the trapezius muscle flap fall?
Type II—characterized by one dominant vascular pedicle and minor pedicles.
What is the primary vascular supply for a Type II trapezius muscle flap?
The dominant pedicle is typically from the transverse cervical artery or dorsal scapular artery, supplemented by minor pedicles from posterior intercostal arteries.
Damage to which nerve can significantly impair trapezius flap function and shoulder stability?
Spinal accessory nerve (CN XI). Injury results in shoulder droop and instability due to impaired trapezius muscle function.
What anatomical landmark is crucial in deciding replantation for single index finger amputations?
Flexor digitorum superficialis (FDS) insertion. Amputations distal to the FDS insertion preserve PIPJ function and thus are favorable indications for replantation.
True or False: Anticoagulation post-digit replantation significantly improves outcomes.
False. There is currently no strong evidence (Level I-III) supporting improved outcomes with anticoagulation after digital replantation.
What is the most common late secondary procedure following a successful finger replantation?
Tenolysis. Tenolysis is the most frequent secondary procedure post-replantation, addressing adhesions and stiffness.
What is the axial vessel supplying the Moberg flap?
The Moberg flap is axial-pattern, based specifically on digital arteries supplying the thumb.
What type of flap is the reversed homo-digital island flap considered (axial or random)?
Axial-pattern flap. It relies on retrograde flow through digital arterial communications at the DIP joint level.
Optimal initial management for extravasation injury with chemotherapy agents classified as DNA-binding vesicants includes which approach?
Immediate localization, neutralization, and targeted treatment. For severe extravasation injuries, Dexrazoxane is indicated, along with cold compresses to limit tissue damage.
What is the first-line pharmacological therapy indicated for severe extravasation injury from anthracycline chemotherapy agents?
Dexrazoxane administration, initiated promptly, significantly mitigates tissue damage and is recommended for severe anthracycline extravasations.
Why are warm compresses contraindicated in the acute phase of DNA-binding chemotherapy extravasation?
Warm compresses exacerbate spread, potentially worsening tissue necrosis;
cold compresses localize and limit injury.
According to Cormack and Lamberty classification, what flap type is a radial forearm free flap?
Type C fasciocutaneous flap (fascial flap with axial blood supply), having reliable perfusion from radial artery perforators.
During radial forearm osteocutaneous flap harvest, which cortical part of the radius must always remain intact?
Dorsal cortex. Only unicortical bone harvest from the distal radius is permitted to avoid fracture risk postoperatively.
Describe the standard direction of flap elevation and the anatomical landmarks of pedicle dissection in a radial forearm flap.
Dissection occurs distal-to-proximal, preserving paratenon over flexor carpi radialis, with the pedicle dissected deep to brachioradialis muscle and tendon.
Which forearm muscle is typically affected first by ischemia in missed compartment syndrome resulting in Volkmann’s contracture?
Flexor Digitorum Profundus (FDP). Deep volar muscles, especially FDP and Flexor Pollicis Longus (FPL), are usually affected first.
What’s the most common cause of compartment syndrome in the adult upper limb?
Distal radius fractures. They frequently precede compartment syndrome, potentially leading to Volkmann’s ischemic contracture.
In severe Volkmann’s ischemic contracture cases, what advanced reconstruction technique may be indicated?
Functional muscle transfer, commonly using the gracilis muscle, can restore function in severe cases.
Which organism most commonly infects wounds associated with medicinal leech therapy?
Aeromonas hydrophilia, a commensal bacterium living symbiotically within the gut of medicinal leeches.
What antibiotic class is recommended prophylactically during leech therapy to prevent Aeromonas infections?
Fluoroquinolones, particularly **ciprofloxacin, **effectively target Aeromonas hydrophilia.
True or False: Leeches should be forcibly removed if not detaching spontaneously to prevent infection.
**False. **Forceful removal increases the risk of infection by leaving behind teeth and regurgitating gut flora.
Which condition is an absolute contraindication for negative pressure wound therapy (NPWT)?
**Application directly on malignant tissue **awaiting histological confirmation is absolutely contraindicated.
Can NPWT safely be used directly over exposed tendons or bone?
Only cautiously. Direct NPWT may desiccate tendons or bones if not adequately hydrated or protected.
Why should NPWT not be used as a definitive solution for wounds?
NPWT is temporizing and promotes granulation but should not replace definitive coverage with grafts or flaps.
Which tissue has higher electrical resistance: fat or muscle?
Fat has higher electrical resistance than muscle, influencing the pattern of injury seen in electrical burns.
True or False: Alternating current (AC) poses a higher cardiac risk than direct current (DC).
True. AC is more dangerous, causing cardiac dysrhythmias at lower amperages compared to DC.
Are injuries from electrical sources above 1000 volts considered high-voltage injuries?
Yes. Clinically, electrical injuries above 1000 volts are classified as high-voltage injuries.
What is the optimal initial management of frostbite to the hand and fingers?
Rapid rewarming by immersion for 30 minutes at 40-44°C, ensuring controlled thawing and limiting tissue damage.
Should immediate amputation be performed on frostbitten digits with obvious necrosis upon initial presentation?
No. Immediate amputation should be avoided until clear demarcation between viable and necrotic tissue develops, typically 6-24 hours later.
Why is rewarming frostbitten tissue at temperatures higher than 44°C contraindicated?
Higher temperatures (e.g., 60°C) risk additional thermal injury and tissue necrosis, worsening outcomes.
What are the four classical Kanavel signs of suppurative flexor tenosynovitis?
- Fusiform swelling of the digit
- Pain on passive extension
- Tenderness along the flexor sheath
- Digit held in a flexed posture
Classically described by Kanavel for diagnosing suppurative flexor tenosynovitis.
Which scoring system uses hemoglobin levels among its criteria for diagnosing necrotizing fasciitis?
Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score.
Considers hemoglobin, WBC, sodium, creatinine, glucose, and CRP to predict likelihood of necrotizing fasciitis.
Which epidermal layer is exclusive to glabrous (hairless) skin such as palms and soles?
Stratum lucidum.
A clear epidermal layer beneath the stratum corneum, exclusive to palms and soles.
What is the primary proliferative layer of epidermis containing mitotically active stem cells?
Stratum germinativum (stratum basale).
Responsible for epidermal regeneration and contains melanocytes.
Which epidermal layer forms the primary barrier to fluid loss and infection?
Stratum corneum.
Made of dead keratinocytes, forming the outermost barrier layer.
Why prioritize thumb reconstruction over the index finger in combined traumatic injuries?
Thumb function is critical for opposition, grasp, and hand functionality, making reconstruction a priority.
Optimizing thumb function significantly enhances overall hand utility.
Why is heterotopic replantation beneficial in thumb reconstruction using an amputated index finger?
It restores functional thumb length and opposition, improving grip compared to isolated digit amputation.
Enables maximal functional recovery after severe trauma.
Define an “angiosome.”
Three-dimensional tissue block supplied by a single underlying source artery.
Introduced by Taylor and Palmer, fundamental for flap reconstruction.
What is a “perforasome”?
Vascular territory supplied by a single perforator artery.
Refined concept by Saint-Cyr for precise perforator flap planning.
Who first introduced the angiosome concept and why is it significant in plastic surgery?
Taylor and Palmer (1987).
Revolutionized reconstructive flap surgery by mapping tissue vascular territories.
Immediate management for fingertip hydrofluoric acid burns with persistent pain?
Remove fingernails, irrigate thoroughly, apply calcium gluconate 10% gel.
Calcium gluconate counters fluoride-ion-induced pain and tissue damage.
Why does hydrofluoric acid cause systemic toxicity?
Fluoride ions bind calcium ions causing hypocalcemia and electrolyte disturbances, potentially leading to cardiac arrhythmias.
Systemic toxicity results from disruption of calcium homeostasis.
Why should immediate surgical excision generally be avoided in initial hydrofluoric acid burns?
Tissue necrosis is delayed; conservative initial management allows precise assessment of burn depth, avoiding unnecessary tissue removal.
Prefer initial conservative therapy; surgery planned subsequently based on demarcation.
What is the vascular supply for the Becker flap?
Dorsal branch of the ulnar artery.
What is the vascular supply for the lateral arm flap?
Posterior radial collateral artery.
What artery provides blood supply to the anterolateral thigh flap (ALT)?
Descending branch of lateral femoral circumflex artery.
The Foucher flap is based on which artery?
First dorsal metacarpal artery.
Which artery supplies the parascapular flap?
Descending branch of circumflex scapular artery.
Which organism causes Hansen’s disease (Leprosy)?
Mycobacterium leprae.
Organism responsible for cat-scratch disease?
Bartonella henselae.
Organism causing subcutaneous fungal infections in gardeners and florists?
Sporothrix schenckii.
Which organisms cause mucormycosis leading to digital gangrene?
Phycomycetes.
Name the common parapox virus transmitted from sheep/goats causing skin lesions.
Orf virus.
Function of low-adherent dressings (e.g., Jelonet/Mepitel)?
Allow exudate to pass through into a secondary dressing.
Primary property of semipermeable films (e.g., Opsite/Tegaderm)?
Permeable to gases and vapor but impermeable to fluids.
Primary role of hydrogel dressings (e.g., Intrasite)?
Donate water to the wound to maintain a moist environment.
Mechanism of hydrocolloid dressings (e.g., Duoderm/Aquacel)?
Form a gel on wound surface, maintaining moist healing environment.
Origin and function of alginate dressings (e.g., Kaltostat)?
Derived from brown seaweed, useful for absorbing exudate and promoting hemostasis.
Which anticoagulant inhibits synthesis of factors II, VII, IX, and X?
Warfarin.
Which drug irreversibly inhibits platelet P2Y12 ADP receptors?
Clopidogrel.
Antiplatelet agent irreversibly inhibiting COX-1?
Aspirin.
Anticoagulant binding antithrombin III, risking thrombocytopenia (HIT)?
Unfractionated heparin.
Proteolytic enzyme commonly used to dissolve thrombi in microsurgery?
Tissue plasminogen activator (t-PA).
Optimal reconstruction for 2.5 cm full-thickness defect with exposed tendon on dorsum of proximal phalanx?
Quaba flap (dorsal metacarpal artery flap).
Best flap for full-thickness defect over the DIPJ dorsum of the ring finger?
Reversed cross-finger flap.
Treatment for volar oblique fingertip amputation, little finger, minimal bone exposed?
Allow to heal by secondary intention.
Best reconstruction option for a 2cm full-thickness thumb pulp defect with exposed distal phalanx?
First dorsal metacarpal artery flap (Foucher flap).
Ideal flap for extensive (6cm by 2cm) hypothenar eminence defect with exposed flexors and nerves?
Becker flap (based on dorsal ulnar artery).
