Complete Knee Dislocation

Aetiology

  • Serious high energy injury (usually - can be low energy in elderly)

Pathophysiology

  • Directions: posterior, anterior, medial, lateral, rotatory

Clinical presentation

  • Pain and instability of the knee

Investigations

  • Check neurovascular status
  • X-ray
  • If concern over neurovascular status - CT angiogram
  • No concern over neurovascular status - MRI

Management

Immediate

  • Emergency reduction under sedation, recheck neurovascular status
  • May need emergency fix for temporary stabilisation
  • May require theatre reduction if medial femoral condyle button-holed through the medial capsule
  • Vascular stenting or by‐pass may be required if neurovascular injury
    • Reperfusion may result in compartment syndrome especially after prolonged ischaemia and fasciotomies may be necessary

Definitive

  • Sequential ligamentous repair

Complications

  • High incidence of complications, especially neurovascular injury (popliteal artery injury, injury to the common peroneal nerve) and ligamentus injury
  • Other complications include arthrofibrosis and stiffness, and ligament laxity