Lower limb trauma Flashcards
Femoral shaft fracture
High energy injuries frequently associated with life-threatening conditions
- Incidence = ____per 100,000 person-years
- Mechanism
3, Associated conditions
- 37.1 per 100,000 person-years
- Traumatic
◾high-energy (most common in younger population; often a result of high-speed MVA)
◾low-energy (more common in elderly eg.fall from standing) - Associated conditions
i) ipsilateral femoral neck fracture
◾2-6% incidence
◾often basicervical, vertical, and nondisplaced
◾missed 19-31% of time
ii) Bilateral femur fractures
◾significant risk of pulmonary complications
◾increased rate of mortality as compared to unilateral fractures
Femoral shaft fracture
Anatomy
Osteology of femur
◾largest and strongest bone in the body
◾femur has an anterior bow
◾linea aspera
◦ rough crest of bone running down middle third of posterior femur
◦ attachment site for various muscles and fascia
◦ acts as a compressive strut to accommodate anterior bow to femur
Femoral shaft fracture
3 compartments of the thigh
i. anterior (muscles and nerve)
ii. posterior (muscles and nerve
iii. adductor (muscles and nerve)
i. Anterior ◾sartorius ◾quadriceps (femoral)
ii. Posterior ◾biceps femoris ◾semiT ◾semimem (sciatic)
iii. Adductor ◾gracilis ◾adductor longus ◾adductor brevis ◾adductor magnus (Obturator)
Femoral shaft fracture: Biomechanics
Deforming force after fracture
- proximal fragment
- distal segment
- Proximal fragment
◾abducted : gluteus medius and minimus abduct as they insert on greater trochanter
◾flexed: iliopsoas flexes fragment as it inserts on lesser trochanter - Distal segment
◾varus : adductors inserting on medial aspect of distal femur
◾extension : gastrocnemius attaches on distal aspect of posterior femur
Femoral shaft fracture
Classification
Winquist and Hansen Classification
Type 0 • No comminution
Type I • Insignificant amount of comminution
Type II • Greater than 50% cortical contact
Type III • Less than 50% cortical contact
Type IV • Segmental fracture with no contact between proximal and distal fragment
Femoral shaft fracture: Presentation
NOTE: Initial evaluation ATLS should be initiated
Physical exam
- Inspection
- Blood loss in closed femoral shaft fractures is ___ to ____ mL
- For closed tibial shaft fractures, ____to____
- Blood loss in open fractures may be ______ that of closed fractures
- ◾tense, swollen thigh; ◾affected leg often shortened;
◾tenderness about thigh - 1000-1500ml
- 500-1000ml
- Double
NOTE:
◾examination for ipsilateral femoral neck fracture often difficult secondary to pain from fracture
◾must record and document distal neurovascular status
Femoral shaft fracture:Treatment
Nonoperative
Treatment: Nonoperative
Long leg cast
◾indications: nondisplaced femoral shaft fractures in patients with multiple medical comorbidities
Femoral shaft fracture: Operative
Antegrade nail (reamed)
- indications
- outcomes
- gold standard for treatment of diaphyseal femur fractures
- Outcomes
a) stabilization within 24 hours is associated with ◾decreased pulmonary complications (ARDS)
◾decreased thromboembolic events
◾improved rehabilitation
◾decreased length of stay and cost of hospitalization
b) EXCEPTION is patient with a closed head injury ◾critical to avoid hypotension and hypoxemia
◾consider provisional fixation (damage control)
Femoral shaft fracture: Operative
Retrograde intramedullary nail with reamed technique
- indications
- outcomes
- Indications
◾ipsilateral femoral neck fracture
◾floating knee (ipsilateral tibial shaft fracture) -use same incision for tibial nail
◾ipsilateral acetabular fracture (does not compromise surgical approach to acetabulum)
◾multiple system trauma
◾bilateral femur fractures (avoids repositioning)
◾morbid obesity - Outcomes
◾results are comparable to antegrade femoral nails
◾immediate retrograde or antegrade nailing is safe for early treatment of gunshot femur fractures
Femoral shaft fracture: Operative
External fixation with conversion to intramedullary nail within 2-3 weeks
- indications
- indications
◾unstable polytrauma victim
◾vascular injury
◾severe open fracture
Femoral shaft fracture: Operative
ORIF with plate
- indications
- outcomes
- indications
◾ipsilateral neck fracture requiring screw fixation
◾fracture at distal metaphyseal-diaphyseal junction
◾inability to access medullary canal
2. outcomes
◾inferior when compared to IM nailing due to increased rates of:
◾infection
◾nonunion
◾hardware failure
Femoral shaft fracture: Surgical Techniques
Entry point: piriformis entry vs trochanteric
1. Piriformis - pros
- trochanteric entry -pros
- piriformis entry - pros
◾colinear trajectory with long axis of femoral shaft
(* higher AVN risk in paediatric patient) - trochanteric entry - pros
◾minimizes soft tissue injury to abductors
◾easier starting point than piriformis entry nail
Femoral shaft fracture: Surgical Techniques
Reamed vs unreamed antegrade nail
- Which is superior ? / Why (3)
- Indications for unreamed nail
- Interlocking screws : technique
- reamed nailing superior to unreamed nailing with
◾increased union rates
◾decreased time to union
◾no increase in pulmonary complications - Consider for patient with bilateral pulmonary injuries
- Interlocking screws : technique
◾computer-assisted navigation for screw placement decreases radiation exposure
◾widening/overlap of the interlocking hole in the proximal-distal direction ◾correct with adjustment in the abduction/adduction plane
◾widening/overlap of the interlocking hole in the anterior-posterior plane ◾correct with adjustment in the internal/external rotation plane
Femoral shaft fracture: Surgical Techniques
Antegrade nail
- Pros
- Cons
- Pros
◾98-99% union rate
◾low complication rate
◾infection risk 2% - Cons
◾not indicated for use with ipsilateral femoral neck fracture
◾increased rate of HO in hip abductors
◾> rate of hip pain compared with retrograde nailing
◾mismatch of the radius of curvature of the femoral shaft and intramedullary nails can lead to anterior perforation of the distal femur
Femoral shaft fracture: Surgical Techniques
Retrograde intramedullary nailing
- approach
- technique : Entry point
- approach
◾2 cm incision starting at distal pole of patella
◾medial parapatellar versus transtendinous approaches
◾nail inserted with knee flexed to 30-50 degrees - Entry point
◾center of intercondylar notch on AP view
◾extension of Blumensaat’s line on lateral (posterior to Blumensaat’s line risks damage to cruciate ligaments)
Femoral shaft fracture: Surgical Techniques
Retrograde intramedullary nailing
- pros
- cons
- pros
◾technically easier
◾union rates comparable to those of antegrade nailing
◾no increased rate of septic knee with retrograde nailing of open femur fractures - cons
◾knee pain
◾increased rate of interlocking screw irritation
◾cartilage injury
◾cruciate ligament injury with improper starting point
Femoral shaft fracture: Surgical Techniques
External fixation with conversion to intramedullary nail within 2-3 weeks
- technique
◾safest pin location sites are _______
◾__ pins should be used on each side of the fracture line - pros
- cons
- technique
◾anterolateral and direct lateral regions of the femur
◾2 pins should be used on each side of the fracture line - Pros
◾prevents further pulmonary insult without exposing patient to risk of major surgery
◾may be converted to IM fixation within 2-3 weeks as a single stage procedure - Cons
◾pin tract infection
◾knee stiffness
◾due to binding/scarring of quadriceps mechanism
Femoral shaft fracture: Surgical Technique
Special considerations
- Ipsilateral femoral neck fracture
a) prioriry
b) technique : preferred methods
c) technique : less preferred methods
Ipsilateral femoral neck fracture
a) priority goes to fixing femoral neck because anatomic reduction is necessary to avoid complications of AVN and nonunion
b) technique : preferred methods
◾screws for neck with retrograde nail for shaft
◾screws for neck and plate for shaft
◾compression hip screw for neck with retrograde nail for shaft
c) less preferred methods
◾antegrade nail with screws anterior to nail (technically challenging)
Femoral shaft fracture: Complications (11)
- Heterotopic ossification–>(incidence=25%;treatment=rarely clinically significant)
- Pudendal nerve injury–>(◦incidence=10% when using fracture table with traction)
- Femoral artery or nerve injury–>(◦incidence=rare;–>◦cause=can occur when inserting proximal interlocking screws during a retrograde nail)
- Malunion & rotational malalignment (see separate card)
- Delayed union(◦treatment◾dynamization of nail with or without bone grafting)
- Nonunion(◦incidence◾<10%;–>◦risk factors◾postoperative use of nonsteroidal anti-inflammatory drugs◾smoking is known to decrease bone healing in reamed antegrade exchange nailing for atrophic non-unions; –>◦treatment◾reamed exchange nailing)
7.Infection(◦incidence◾< 1%;–>◦treatment◾removal of nail and reaming of canal OR external fixation used if fracture not healed) - Weakness(◦quadriceps and hip abductors are expected to be weaker than contralateral side)
- Iatrogenic fracture etiologies–>(◦risk factors=◾antegrade starting point 6mm or more anterior to the intramedullary axishowever, anterior starting point improves position of screws into femoral head;◾failure to overream canal by at least .5mm)
- Mechanical axis deviation (MAD)–>(◦lengthening along the anatomical axis of the femur leads to lateral MAD
◦shortening along the anatomical axis of the femur leads to medial MAD) - Anterior cortical penetration
Femoral shaft fracture: Complications
Malunion and rotational malalignment
- Most accurately determined by the ______ method
- Decribe this
- Malrotation up to ____degrees is usually well tolerated
- Incidence
a) proximal fractures ____%
b) distal fractures ____% - Risk factors
a) use of a fracture table ______ risk of internal rotation deformities when compared to manual traction
b) fracture ______
c) ______ surgery - Treatment
a) intraop
b) postop
- Jeanmart method
- angle between a line drawn tangential to the femoral condyles and a line drawn through the axis of the femoral neck
- 15 degrees
4a. 30%
4b. 10%
- Risk factors
a) increases risk compared to manual traction
b) fracture comminution
c) night-time surgery - Treatment
a) Remove distal interlocking screws and manually correct rotation
b) Osteotomy is required
Patella Fracture
1. incidence: patella fractures account for ___% of all skeletal injuries
- male to female __:__
- most fractures occur in __to__ year olds
- high-energy dashboard injuries are associated with i, ii or iii
- Prognosis: osteonecrosis reported to occur in up to ___% but not found to affect clinical outcome
- 1%
- 2:1
- 20-50 yo
- i) femoral neck; ii) posterior wall acetabular fracture; iii) knee dislocation
- 25%
Patella Fracture
Mechanism of injury (2)
- Direct impact injury
◾occurs from fall or dashboard injury
◾causes failure in compression - Indirect eccentric contraction
◾occurs from rapid knee flexion against contracted quads muscle (causes failure in tension)
◾patella sleeve fracture
◾seen in pediatric population (8-10 year olds)
◾high index of suspicion required
Patella Fracture - Anatomy
Osteology
- Superior ___% of posterior surface covered by articular cartilage
- articular cartilage thickest in body - up to __mm
- posterior articular surface comprised of a (largest) and _b_facets separated by a c
Soft tissue attachments
4. _(a)_and (b) attach to anterosuperior margin
- quadriceps tendon comprised of 3 layers
a)
b)
c)
6.________attaches to inferior margin - Blood Supply
a) derives from anastomotic ring originating from ________arteries
b) most important blood supply to the patella is located ________
- 75%
- 10mm
- (a) lateral (largest); (b) medial; (c) vertical ridge
Soft tissue attachments
4. (a) quadriceps tendon; (b) fascia lata
5a) superficial layer formed from rectus femoris tendon
5b) middle layer: formed by vastus med. + lat. tendons
5c) deep layer: formed by vastus intermedius tendon
- patellar tendon
- Blood Supply
a) geniculate arteries
b) at the inferior pole
Patella Fracture
Classification
Can be described based on fracture pattern: ◾nondisplaced
◾displaced:
◦ step-off >2-3mm or
◦ fracture gap >1-4mm
◾ transverse
◾ pole or sleeve (upper or lower)
◾ vertical
◾ marginal
◾ osteochondral
◾ comminuted (stellate)Patella Fracture
Physical exam
- inspection
- motion
- provocative tests
1 Inspection
◾palpable patellar defect
◾significant hemarthrosis
- motion
◾unable to perform straight leg raise indicates failure of extensor mechanism (retinaculum disrupted –> can aspirate hemarthrosis and inject local anesthetic if patient unable to perform due to pain)\ - provocative tests
◾perform saline load test to rule out open fracture
Patella Fracture
XR Findings
◾fracture displacement (degree of fracture displacement correlates with degree of retinacular disruption)
◾patella alta =Insall-Salvati ratio <1 (indicates disruption of patellar tendon)
◾patella baja = Insall-Salvati ratio >1 (indicates disruption of quads tendon)
Patella Fracture
Bipartite patella - may be mistaken for patella fracture
- affects __% of population
- characteristic _______ position
- bilateral in __% of cases
- affects 8% of population
- characteristic superolateral position
- bilateral in 50% of cases
Patella # Rx
TBC
Knee Dislocation
Devastating injury resulting from high or low energy
- high-energy MOI
- low-energy MOI
- Associated with significant soft tissue disruption with ____ of ligaments generally disrupted
- Prognosis
- usually from MVC or fall from height; commonly a dashboard injury resulting in axial load to flexed knee
- often from athletic injury; generally has a rotational component; morbid obesity is a risk-factor
- 75% (3/4)
- complications frequent and rarely does knee return to pre-injury state
Knee Dislocation : Associated injuries
Vascular injury
1) __to__% in all dislocations
2) __to__% in anterior/posterior dislocations
3) due to tethering at the popliteal fossa
a) Proximal - fibrous tunnel at the _____ ?
b) Distal - fibrous tunnel at _______?
Nerve injury
4) usually ___________ (25%)
5) _______ nerve injury is less common
Fractures
6) present in __%
7. _____ and _____ most common
- 5-15% in all dislocations
- 40-50% in anterior/posterior dislocations
3a. fibrous tunnel at adductor hiatus
3b. fibrous tunnel at soleus muscle - common peroneal nerve injury (25%)
- tibial nerve
- 60%
- tibia and femur
Knee Dislocation - classification
Kennedy classification based on direction of displacement of the tibia (5 types)
anterior (30-50%)
◾most common
◾due to hyperextension injury
◾usually involves tear of PCL
◾arterial injury generally intimal tear due to traction
posterior (25%)
◾2nd most common
◾due to axial load to flexed knee (dashboard injury)
◾highest rate of vascular injury (25%) (direction of dislocation)
◾highest rate of complete tear of popliteal artery
lateral (13%)
◾due to varus or valgus force
◾usually involves tears of both ACL and PCL
◾highest rate of peroneal nerve injury
medial (3%)
◾varus or valgus force
◾usually disrupted PLC and PCL
rotational (4%)
◾posterolateral most common rotational dislocation
◾usually irreducible
◾buttonholding of femoral condyle through capsule
Knee Dislocation - Classification
Schenck Classification : based on pattern of multiligamentous injury of knee dislocation (KD)
Schenck Classification
◾KD I: Multilig injury with involvement of ACL or PCL
◾KD II Injury to ACL and PCL only (2 ligaments)
◾KD III Injury to ACL, PCL, and PMC or PLC (3 ligaments).
- KDIIIM (ACL, PCL, MCL) and - KDIIIL (ACL, PCL, PLC, LCL). * note: KDIIIM has highest rate of vascular injury (31%) based on Schenck classification
◾KD IV Injury to ACL, PCL, PMC, and PLC (4 ligaments)
◾KD V Multiligamentous injury with periarticular fracture
Knee Dislocation
Physical exam
- Appearance
a) no obvious deformity
b) obvious deformity - Stability
1 Appearance
a) no obvious deformity
◾50% spontaneously reduce before arrival to ED (therefore underdiagnosed)
◾may present with subtle signs of trauma (swelling, effusion, abrasions)
b) obvious deformity
◾reduce immediately, especially if absent pulses
◾”dimple sign” - buttonholing of medial femoral condyle through medial capsule
–> indicative of an irreducible posterolateral dislocation
–> ◾a contraindication to closed reduction due to risks of skin necrosis
- Diagnosis based on instability on exam (radiographs and gross appearance may be normal)
Knee Dislocation : Physical exam
- Vascular exam
NOTE: collateral circulation can mask a complete popliteal artery occlusion
- Action if ABI >0.9 ? (with pulses normal and present)
- Action if ABI <0.9 ? (with pulses normal and present)
- If pulses are absent or diminished:
a)
b)
c) ischemia time >8 hours= amputation risk up to ____%
d) if pulses present after reduction then measure ABI then consider ______ vs. ________
Vascular exam
◾priority is to rule out vascular injury on exam both before and after reduction
◾serial examinations are mandatory
◾palpate the dorsalis pedis and posterior tibial pulses
- monitor with serial examination (100% Negative Predictive Value)
- perform arterial duplex ultrasound or CT angiography
◾if arterial injury confirmed then consult vascular surgery - If pulses are absent or diminished
a) confirm that the knee joint is reduced or perform immediate reduction and reassessment
b) immediate surgical exploration if pulses are still absent following reduction
c) 86%
d) observation vs. angiography
https://www.vumedi.com/video/knee-clinical-examination-360-view-of-instability/
Knee Dislocation : Treatment
Initial Treatment
Nonoperative
- Reduce knee and re-examine vascular status
** considered an orthopedic emergency **
◾splint in 20-30° flexion
◾confirm reduction is held with repeat radiographs in brace/splint
◾vascular consult indicated if –> arterial injury confirmed by arterial duplex ultrasound or CT angiography OR pulses are absent or diminished following reduction - Nonoperative - indications
◾limited and most cases require surgical stabilization
Knee Dislocation : Treatment
- Emergent surgical intervention with external fixation
a) indications (6)
b) technique - Delayed ligamentous reconstruction/repair
a) indications
b) technique
1. Emergent surgical intervention with external fixation a) indications ◾vascular repair (takes precedence) ◾open fx and open dislocation ◾irreducible dislocation ◾compartment syndrome ◾obese ◾multi trauma patient
b) technique : vascular intervention
◾perform external fixation first
◾excision of damaged segment and repair with reverse saphenous vein graft
◾always perform fasciotomies after vascular repair
- Delayed ligamentous reconstruction/repair
a) indications
◾generally instability will require some kind of ligamentous repair or fixation
◾patients can be placed in a knee immobilizer for 6 weeks for initial stabilization
◾improved outcomes with early treatment (within 3 weeks)
b) technique
◾PLC : early reconstruction before ACL reconstruction
◾postoperative: recommend early mobilization and functional bracing
Knee Dislocation : Complications
- Most common complication ? ◦more common with delayed mobilization
- Laxity and instability ___%
- Peroneal nerve injury __%
◦most common in ______ dislocations
◦poor results with acute, subacute, and delayed (>3 months) nerve exploration
◦neurolysis and tendon transfers are the mainstay of treatment
◦Dynamic tendon transfer involves transferring the posterior tibial tendon (PTT) to the lateral cuneiform. - ______ compromise
- Stiffness / arthrofibrosis (38%): more common with delayed mobilization
- Laxity and instability (37%)
- Peroneal nerve injury (25%)
◦most common in posterolateral dislocations
◦poor results with acute, subacute, and delayed (>3 months) nerve exploration
◦neurolysis and tendon transfers are the mainstay of treatment
◦Dynamic tendon transfer involves transferring the posterior tibial tendon (PTT) to the lateral cuneiform. - Vascular compromise: in addition to vessel damage, claudication, skin changes, and muscle atrophy can occur
Proximal third tibia fractures
- High rates of malunion - malalignment ?
- Assoc with _____ compromise ?
- Incidence= __to__% of all tibial shaft fractures
- Mechanism
- Associated conditions (2)
- valgus AND apex anterior (procurvatum)
- soft tissue compromise
- 5-11%
- MOI:
◾low energy (result of torsional injury / indirect trauma)
◾high energy (direct trauma) - Associated conditions
◾compartment syndrome
◾soft tissue injury (critical to outcome)
Proximal third tibia fractures
Deforming forces
proximal fracture extended, apex anterior, varus
◾apex extended due to patellar tendon
◾varus due to pes anserinus + anterior compartment
distal fragment flexed
◾flexed due to hamstrings
Proximal third tibia fractures: Treatment of Closed Tibia Fractures
Nonoperative: closed reduction / cast immobilization
1. indications = closed low energy fractures with acceptable alignment (parameters) ◾< \_\_\_ degrees varus-valgus angulation ◾ \_\_\_% cortical apposition ◾< \_\_\_cm shortening ◾< \_\_\_ degrees rotational alignment
- technique
- outcome
1. acceptable alignment (parameters) ◾< 5 degrees varus-valgus angulation ◾< 10 degrees anterior/posterior angulation ◾> 50% cortical apposition ◾< 1 cm shortening ◾< 10 degrees rotational alignment
- technique
◾place in LL case; convert to functional brace at 4 weeks ◾cast in 10 to 20 degrees of flexion - Rotational control is difficult to achieve by closed methods
Proximal third tibia fractures : Operative
- External fixation
a) indications
b) technique - Intramedullary nailing
a) indications
b) outcomes
- External fixation
a) indications
◾fractures with extensive soft-tissue compromise
◾polytrauma
b) technique
◾bi-planar and multiplanar pin fixators are useful - Intramedullary nailing
a) indications
◾enough proximal bone to accept two locking screws (5-6 cm)
b) outcomes
◾high rates of malunion with improper technique ◾most common malunion = valgus AND procurvatum
Proximal third tibia fractures: Operative
- Percutaneous locking plate
a) indications
b) technique
c) outcomes
a) indications
◾inadequate proximal fixation for IM nailing
◾best suited for transverse or oblique fractures
◾minimal soft-tissue compromise
b) technique
◾may be used medially or laterally
◾better soft tissue coverage laterally makes lateral plating safer
c) outcomes
◾lateral plating with medial comminution can lead to varus collapse
◾long plates may place superficial peroneal nerve at risk
Proximal third tibia fractures : IMN
Surgical technique
- approach
- starting point
- approach
◾lateral parapatellar- helps maintain reduction for proximal 1/3 fractures
- requires mobile patella
- medial parapatellar may lead to valgus deformity
◾suprapatellar - facilitates nailing in semiextended position
- starting point
◾proximal to the anterior edge of the articular margin
◾just medial to the lateral tibial spine
◾use of a more lateral starting point may decrease valgus deformity
◾use of a medial starting point may create valgus deformity
Proximal third tibia fractures : IMN
Surgical technique
- Fracture reduction techniques
a) blocking (Poller) screws
b) unicortical plating
c) universal distractor
- Fracture reduction techniques
a) Blocking (Poller) screws
◾coronal blocking screw- prevents apex anterior (procurvatum) deformity
- place in posterior half of proximal fragment)
◾sagittal blocking screw - prevents valgus deformity
- place on lateral concave side of proximal fragment
◾enhance construct stability if not removed
b) unicortical plating
◾short one-third tubular plate placed anteriorly, anteromedially, or posteromedially across fracture
◾secure both proximally and distally with 2 unicortical screws
c) universal distractor
◾Schanz pins inserted from medial side, parallel to joint
◾pin may additionally be used as blocking screws
Proximal third tibia fractures : IMN
Surgical technique
- nail insertion : options (2)
- Locking screws
a) Static vs dynamic locking ?
b) number of screws?
- nail insertion options
a) standard insertion with knee in flexion
b) nail insertion in semiextended position
◾may help to prevent procurvatum deformity
◾neutralizes deforming forces of ext mechanism
- Locking screws
a) statically lock proximally and distally for rotational stability ◾no indication for dynamic locking acutely
b) must use at least two proximal locking screws
Proximal third tibia fractures
Complication: Malunion
- incidence = __to__% rate of malunion following intramedullary nailing (valgus/procurvatum)
- treatment
- Prevention (4)
- 20-60%
- Treatment
◾revision intramedullary nailing
OR
◾osteotomy if fracture has healed - Prevention
i. blocking screws
ii. temporary plating
iii. universal distractors
iv. nailing in semiextended position
Subtalar Dislocations
- Mechanism
- ___% open
- Medial vs lateral dislocations (%)
- Associated dislocations
- Associated fractures in up to ___%
- Fractures with medial dislocation (3)
- Fractures with lateral dislocation (4)
- Typically from a high-energy mechanism
- 25% may be open (lateral dislocations more likely to be open)
- 65% to 80% are medial; remaining are lateral
(note: case reports of anterior or posterior dislocations) - talonavicular
- 44%
- (i)dorsomedial talar head; (ii) posterior process of talus ; (iii) navicular
- (i) cuboid; (ii) anterior calcaneus; (iii) lateral process of talus; (iv) fibula
Subtalar Dislocation Presentation
- foot will be locked in ______ with medial dislocation
- foot will be locked in ______ with lateral dislocation
Imaging : Radiographs
Findings
3. medial dislocation
4. lateral dislocation
- supination
- pronation
- medial dislocation
◾talar head will be superior to navicular on lateral view - lateral dislocation
◾talar head will be collinear or inferior to navicular on lateral view
Subtalar Dislocations: Treatment
Nonoperative with closed reduction and short leg non-weight bearing cast for 4-6 weeks
- indications
- __to__% can be reduced by closed methods
- Technique maneuvers for reduction
- first line of treatment
- 60-70%
- Technique
◾requires adequate sedation
◾typical maneuvers include knee flexion and ankle plantar flexion
◾followed by distraction and hindfoot inversion or eversion depending on direction of dislocation
◾perform a post-reduction CT to look for associated injuries
Subtalar Dislocations: Treatment
Operative: ie. open reduction
- indications
- Up to ___% require open reduction
- medial dislocation reduction blocked by: (3)
- lateral dislocation reduction blocked by: (3)
- If unstable post reduction ?
- failure of closed reduction
- 32%
- medial dislocation reduction blocked by
◾ peroneal tendons
◾extensor digitorum brevis
◾talonavicular joint capsule - lateral dislocation reduction blocked by:
◾PTT is the most common
◾ FHL
◾ FDL - Place temporary transarticular pins as needed
Subtalar Dislocations : Complications
Post-traumatic Arthritis
◾ Long-term follow up of these injuries show degenerative changes
◾Subtalar joint most commonly affected
◾Up to 89% of have radiographic arthrosis
◾Up to 63% of have symptomatic arthrosis
Talus Fracture (other than neck)
Epidemiology
- Less than __% of all fractures
- ______ most common tarsal fractures after calcaneus fxs
- talar body fractures: account for __to__% of talus fractures
- lateral process fractures: account for ___% of talus fractures
- Talar head fracture: _____common talus fracture
- less than 1%
- second
- 13-23% of talus fractures
- 10.4% of talus fractures
- LEAST common talus fracture
Talus Fracture (other than neck)
Mechanism
1. talar body
- lateral process of talus
- Prognosis
- talar body
◾injuries often result from high energy trauma, with the hindfoot either in supination or pronation - lateral process of talus
◾injuries result from forced dorsiflexion, axial loading, and inversion with external rotation
◾often seen in snowboarders - Prognosis
◾ lateral process injuries have a favorable outcomes with prompt diagnosis and immediate treatment
Talus Fracture (other than neck) : Anatomy 1. Number of muscular and tendinous attachments
- There are ___ articulating surfaces
- ____% of talus is covered by cartilage
- inferior surface articulates with ________
- talar head articulates with: (2)
- lateral process articulates with: (2)
- posterior process consist of medial and lateral tubercle separated _______
- Zero
- 5 articulating surfaces
- 70%
- Posterior facet of calcaneus
- i) navicular bone; ii) sustenaculum tali
- i) posterior facet of calcaneus; ii) lateral malleolus of fibula (this forms the lateral margin of the talofibular joint)
- groove for FHL
Talus Fracture (other than neck): Anatomy
Blood supply : because of limited soft tissue attachments, the talus has a direct extra-osseous blood supply
Sources include (4)
- Posterior tibial artery
◾via artery of tarsal canal (most important and main supply) –> supplies most of talar body
◾via calcaneal braches –> supplies posterior talus - Anterior tibial artery
◾supplies head and neck - Perforating peroneal arteries via artery of tarsal sinus –> supplies head and neck
- Deltoid artery (located in deep segment of deltoid ligament)
◾supplies body
◾may be only remaining blood supply with a talar neck fracture
Talus Fracture (other than neck)
Anatomic classification
- Lateral Process Fx (2 types)
Lateral Process Fx
◾type 1 fractures do not involved the articular surface
◾type 2 fractures involve the subtalar and talofibular joints
◾type 3 fractures have comminution
◦Posterior Process Fx
◾posteromedial tubercle fractures ◾result from an avulsion of the posterior talotibial ligament or posterior deltoid ligament
◾posterolateral tubercle fractures ◾result from an avulsion of the posterior talofibular ligament
◦Talar Head Fx
◦Talar Body Fx
Talus Fracture (other than neck)
Anatomic classification
i. Posterior Process Fx (2 types)
Others
ii. Talar head fx
iii. Talar body fx
- Posteromedial tubercle fractures
◾result from an avulsion of the posterior talotibial ligament or posterior deltoid ligament - posterolateral tubercle fractures
◾result from an avulsion of the posterior talofibular ligament
Talus Fracture (other than neck)
Imaging
- What is Canale view
Canale View: optimal view of talar neck
◾technique
◾maximum equinus
◾15% pronated
◾Xray 75 degrees cephalad from horizontal
NB:
◾careful not to mistake os trigonum (present in up to 50%) for fracture
◾may be falsely negative in talar lateral process fx
Talus Fracture (other than neck)
Treatment : Nonoperative with SLC for 6 weeks
- indications
Treatment : Operative
2. Options
- Indications
◾nondisplaced (< 2mm) lateral process fractures
◾nondisplaced (< 2mm) posterior process fractures
◾nondisplaced (< 2mm) talar head fractures
◾nondisplaced (< 2mm) talar body fractures
Talus Fracture (other than neck)
Treatment : Operative
- ORIF/Kirshner wire Fixation
◾indications ◾displaced (> 2mm) lateral process fractures
◾displaced (> 2mm) talar head fractures
◾displaced (> 2mm) talar body fractures
- medial, lateral or posterior malleolar osteotomies may be necessary
◾displaced (> 2mm) posteromedial process fractures
- may require osteotomies of posterior or medial malleoli to adequately reduce the fragments - fragment excision : indications
◾comminuted lateral process fractures
◾comminuted posterior process fractures
◾nonunions of posterior process fractures
Talus Fracture (other than neck)
- Complications (5)
- What does Hawkins indicate?
- Rate of ST arthritis after lateral process fractures, treated either non-operatively or operatively ?
- Complications
i. AVN
ii. Talonavicular arthritis (PTOA is common in all of these fractures; this can be treated with an arthrodesis of the talonavicular joint)
iii. Malunion
iv. Chronic pain from symptomatic nonunion (may have pain up to 2 years after treatment)
v. Subtalar arthritis - hawkins sign
◾subchondral lucency best seen on mortise Xray at 6-8 weeks ◾indicates intact vascularity with resorption of subchondral bone - 45%
Talus Fracture (other than neck)
Surgical Technique
ORIF/Kirshner Wires
- approaches (4)
Approaches
- lateral approach
◾for lateral process fractures
◾incision over tarsal sinus, reflect EDB distally - posteromedial approach
◾for medial tubercle of posterior process fracture or for entire posterior process fracture that has displaced medially
◾between FDL and neurovascular bundle - posterolateral approach
◾for lateral tubercle of posterior process fractures
◾between peroneal tendons and Achilles tendon (protect sural nerve)
◾beware when dissecting medial to FHL tendon (neurovascular bundle lies there) - combined lateral and medial approach
◾required for talar body fractures with more than 2 mm of displacement
Talar Neck Fractures
- incidence
- mechanism
- associated conditions
- most common fracture of talus ( 50%)
- MOI
◾ a high-energy injury
◾ is forced dorsiflexion with axial load - ipsilateral lower extremity fractures common
Talar Neck Fractures
Classification
1. Eponymous name
◾ details and % risk of AVN (4 types)
- Hawkins Classification
◾ Hawkins I: Nondisplaced (0-13% AVN)
◾ Hawkins II: Subtalar dislocation (AVN risk 20-50%)
◾ Hawkins III: Subtalar and tibiotalar dislocation (AVN risk 20-100%)
◾ Hawkins IV: Subtalar, tibiotalar, and talonavicular dislocation (AVN risk 70-100%)
Talar Neck Fractures: Treatment
- Initial treatment = emergent reduction in ER
◾indications - Nonoperativeshort leg cast for 8-12 weeks (NWB for first 6 weeks)
◾indications - Operative ◦open reduction and internal fixation
a) indications
b) techniques
c) complications
- initial Rx: emergent reduction in ER
◾all cases require emergent closed reduction in ER - Short leg cast for 8-12 weeks (NWB for first 6 weeks) Indications
◾nondisplaced fractures (Hawkins I)
◾CT to confirm nondisplaced without articular stepoff
3 Operative (ORIF) :
a) indications
◾all displaced fractures (Hawkins II-IV)
b) techniques
◾extruded talus should be replaced and treated with ORIF
c) complications
◾post-traumatic arthritis
◾mal-union
◾non-union
◾infection
◾wound dehiscence
Talar Neck Fractures Surgical Techniques
ORIF
- Approach
- Technique
- Postoperative
- Approach
◾two approaches recommended
- visualize medial and lateral neck to assess reduction
- typical areas of comminution are dorsal and medial
◾anteromedial- between tibialis ant and posterior tib
- preserve soft tissue attachments, especially deep deltoid ligament (blood supply)
- medial malleolar osteotomy to preserve deltoid ligament
◾ anterolateral - between tibia and fib proximally, in line with 4th ray
- elevate extensor digitorum brevis and remove debris from subtalar joint
Talar Neck Fractures Surgical Techniques
ORIF
- Technique
- Postoperative
- Technique
◾anatomic reduction essential
◾variety of implants used including mini and small fragment screws, cannulated screws and mini fragment plates
◾medial and lateral lag screws may be used in simple fracture patterns
◾consider mini fragment plates in comminuted fractures to buttress against varus collapse - Postoperative
◾non-weight-bearing for 10-12 weeks
- NB: timing of surgery NOT as important as anatomical reduciton for reducing rates of AVN *
Talar Neck Fractures : Complications
- Osteonecrosis = __% overall (including all subtypes)
- PTOA
a) ______ arthritis (__%) is the most common complications
b) tibiotalar arthritis __%) - Varus malunion __to__%
◦treatment includes medial opening wedge osteotomy of talar neck - Varus malunion leads to: (2)
- 31%
2a) Subtalar arthritis (50%)
2b) 33% - Varus malunion 25-30%
- Varus malunion leads to
i) decreased subtalar eversion (decreased motion with locked midfoot and hindfoot)
ii) weight bearing on the lateral border of the foot
Tibial Plateau Fractures
Definitions: Periarticular injuries of the proximal tibia frequently associated with soft tissue injuries
- Epidemiology (distribution/age/gender)
- Location
- Epidemiology
◾bimodal distribution
◾males in 40s (high-energy trauma)
◾females in 70s (falls) - Location
◾unicondylar vs. bicondylar
◾frequency = lateral > bicondylar > medial
Tibial Plateau Fractures
Mechanism
◦varus/valgus load with or without axial load
◦high energy
◾frequently associated with soft tissue injuries
◦low energy
◾usually insufficiency fractures
Tibial Plateau Fractures
Associated conditions (4)
- meniscal tears
i) lateral meniscal tear
◾more common than medial
◾associated with Schatzker II fracture pattern
◾associated with >10mm articular depression
ii) medial meniscal tear
◾most commonly assoc with Schatzker IV fractures - ACL injuries
◾more common in type IV and VI fractures (25%) - Compartment syndrome
- Vascular injury
◾commonly associated with Schatzker IV fracture-dislocations
Tibial Plateau Fractures
- Anatomy
- Biomechanics
- Anatomy
a) Osteology lateral tibial plateau
◾convex in shape
◾proximal to the medial plateau
b) Osteology medical tibial plateau
◾concave in shape
◾distal to the lateral tibial plateau
c) Muscles : anterior compartment musculature ◾attaches to anterolateral tibia
d) Muscles :pes anserine
◾attaches to anteromedial tibia
- Biomechanics
◦medial tibial plateau bears 60% of knee’s load
Tibial Plateau Fractures
Classification
Schatzker Classification
Type I Lateral split fracture
Type II Lateral Split-depressed fracture
Type III Lateral Pure depression fracture
Type IV Medial plateau fracture
Type V Bicondylar fracture
Type VI Metaphyseal-diaphyseal disassociation
Tibial Plateau Fractures
Presentation
◾look circumferentially to rule-out an open injury
◾consider compartment syndrome when compartments are firm and not compressible
◾varus/valgus stress testing –> any laxity >10 degrees indicates instability
◾neurovascular exam –> any differences in pulse exam between extremities should be further investigated with anke-brachial index measurement
Tibial Plateau Fractures
Imaging
CT and MRI
CT scan = important to identify articular depression and comminution
Findings
◾lipohemarthrosis indicates an occult fracture
◾fracture fragment orientation and surgical planning
MRI
◦indications ◾not well established
◦findings ◾useful to determine meniscal and ligamentous pathology
Tibial Plateau Fractures
Treatment : Nonoperative
Treatment: Nonoperative
Hinged knee brace, PWB for 8-12 weeks, and immediate passive ROM
Indications
◾minimally displaced split or depressed fractures
◾low energy fracture stable to varus/valgus alignment
◾nonambulatory patients
Tibial Plateau Fractures Operative
- temporizing bridging external fixation w/ delayed ORIF ◾indications ?
- External fixation with limited open/percutaneous fixation of articular segment
◾indications ?
◾outcomes
- temporizing bridging external fixation w/ delayed ORIF
◾indications = significant soft tissue injury ; polytrauma - External fixation with limited open/percutaneous fixation of articular segment
◾indications = severe open fracture with marked contamination ; highly comminuted fractures where internal fixation not possible
◾outcomes = similar to open reduction, internal fixation
Tibial Plateau Fractures
ORIF
a) indications (5)
Indications ◾articular stepoff > 3mm ◾condylar widening > 5mm ◾varus/valgus instability ◾all medial plateau fxs ◾all bicondylar fxs
Tibial Plateau Fractures
ORIF
Outcomes
Outcomes
◾restoration of joint stability is strongest predictor of long-term outcomes
◾postoperative infection after ORIF associated with
- male gender
- smoking
- pulmonary disease
- bicondylar fracture pattern
- intraoperative time over 3 hours
◾timing of definitive fixation (before, during or after) relative to fasciotomy closure does not increase the risk of infection
◾worse results with
- ligamentous instability
- meniscectomy
- alteration of limb mechanical axis > 5 degrees
Tibial Plateau Fractures
Techniques : External fixation (temporary)
a) technique
b) advantages
a) technique
◾two 5-mm half-pins in distal femur, two in distal tibia
◾axial traction applied to fixator
◾fixator is locked in slight flexion
b) advantages
◾allows soft tissue swelling to decrease before definitive fixation
◾decreases rate of infection and wound healing complications
Tibial Plateau Fractures
Techniques : External fixation with limited internal fixation (definitive)
a) technique
b) post-op
c) pros
d) cons
a) technique
◾reduce articular surface either percutaneously or with small incisions
◾stabilize reduction with lag screws or wires (must keep wires >14mm from joint)
◾apply external fixator or hybrid ring fixation
b) post-operative care
◾begin weight bearing when callus is visible on radiographs
◾usually remain in place 2-4 months
c) pros
◾minimizes soft tissue insult
◾permits knee ROM
d) cons
◾pin site complications
Tibial Plateau Fractures
Techniques : ORIF
Approach (5)
a) Approach
1. lateral incision (most common)
◾straight or hockey stick incision anterolaterally from just proximal to joint line to just lateral to the tibial tubercle
- midline incision (if planning TKA in future)
◾can lead to significant soft tissue stripping and should be avoided - Posteromedial incision
◾interval between pes anserinus and medial head of gastrocnemius - Dual surgical incisions with dual plate fixation
◾indications= bicondylar tibial plateau fractures - Posterior
◾can be used for posterior shearing fractures
Tibial Plateau Fractures
Techniques : ORIF
Reduction
◾restore joint surface with direct or indirect reduction
◾fill metaphyseal void with autogenous, allogenic bone graft, or bone graft substitutes
- calcium phosphate cement has high compressive strength for filling metaphyseal void
Tibial Plateau Fractures
Techniques : ORIF
Internal fixation
a) absolute or relative
b) screws
c) plate fixation
a) absolute stability constructs should be used to maintain the joint reduction
b) screws may be used alone for:
- simple split fractures
- depression fractures that were elevated percutaneously
c) plate fixation
i. non-locked plates
◾non-locked buttress plates best indicated for simple partial articular fractures in healthy bone
ii. locked plates
◾advantages
◾fixed-angle construct
◾less compression of periosteum and soft tissue
Tibial Plateau Fractures
Techniques : ORIF
postoperative
postoperative
◾hinged knee brace with early passive ROM
- gentle mechanical compression on repaired osteoarticular segments improves chondrocyte survival
◾NWB or PWB for 8 to 12 weeks
