Instability in multiple directions
Evidence of collateral ligamentous injury combined with peroneal nerve palsy
History of high-energy mechanism
Patients with BMI > 40 commonly report low-energy mechanism
Affected knee may hyperextend relative to unaffected knee when leg is lifted by the foot
Patients with BMI > 40 commonly report low-energy mechanism
Popliteal artery injury
Cannot rule out based on normal distal pulses and Ankle Brachial Index (ABI) > 0.9
Requires definitive vascular imaging or serial exams
Neurologic injuries
Common peroneal nerve injury (25%)
Test for:
Sensation in 1st dorsal web space
Dorsiflexion of foot
Toe extension
Tibial nerve injured (less common)
Fractures
Femur and tibia most common
Check hip and ankle joints for associated fracture
Avulsion fractures common
Compartment syndrome risk high with vascular compromise
Cannot rule out based on normal distal pulses and Ankle Brachial Index (ABI) > 0.9
Requires definitive vascular imaging or serial exams
Requires definitive vascular imaging or serial exams
Common peroneal nerve injury (25%)
Test for:
Sensation in 1st dorsal web space
Dorsiflexion of foot
Toe extension
Tibial nerve injured (less common)
Test for:
Sensation in 1st dorsal web space
Dorsiflexion of foot
Toe extension
Sensation in 1st dorsal web space
Dorsiflexion of foot
Toe extension
Femur and tibia most common
Check hip and ankle joints for associated fracture
Avulsion fractures common
Knee dislocation
Hip dislocation
Knee fractures
Lens dislocation
Patella fracture
Elbow dislocation
Segond fracture
Shoulder dislocation