Ankle fracture

Background

• Always palpate proximal leg to r/o Maisonneuve

Malleolar Fractures

1. Isolated Malleolar
   1. Stable if displaced <2mm, joint surface involvement <25%, and no contralateral or syndesmotic injury
2. Medial Malleolus Fx
   1. Is it really isolated? (frequently associated with lateral or posterior injuries)
3. Posterior Malleolus Fx
   1. Usually occurs in association w/ post. tibiofibular ligament injury / fibular fx
   2. Rarely occurs in isolation!
4. Bimalleolar
   1. Lateral + medial malleoli fx
   2. Unstable
5. Trimalleolar
   1. Lateral + medial + posterior malleoli fx
   2. Requires surgical stabilization

Diagnosis

Imaging

1. Ottowa Ankle Rules
2. 3 views:
   1. AP - Best for isolated lateral and medial malleolar fractures
   2. Oblique (mortise) - Best for evaluating for unstable fracture or soft tissue injury
      1. At a point 1cm proximal to articular surface of tibia the space between the tib/fib should be ≤6cm
   3. Lateral - Best for posterior malleolar fractures

Classification

Danis-Weber system

• type A-fibular Fx at or below the joint line without syndesmotic involvement.
• type B-fib Fx at joint level with partial syndesmotic ligament injury.
• type C-fibular Fx above the joint level and complete syndesmotic disruption.
  • C-diaphyseal (Dupuytren Fx) or proximal fibular Fx (maissoneuve).

Fracture Types

1. lateral malleolar-Tx depends on type A, B, or C
2. A-splinting in ED, 6-8 weeks in cast.NWB for three weeks.
3. B-often requires a surgical repair.
4. C-surgery usually required.

Management

1. Lateral malleolar Fx
   1. Stable - >90% have good clinical result
      1. Treat like severe ankle sprain
   2. Unstable = displacement >2mm, medial fx, or medial ligament disruption
      1. Medial tenderness indicates need for stress xrays to determine degree of instability
2. Medial or posterior malleolar Fx
   1. Must confirm no other injuries!
   2. If non-displaced, isolated:
      1. Short-leg posterior splint (ankle at 90o)
      2. Non-weight bearing
      3. Refer in 5-7 days
3. Lateral malleolar fx with deltoid injury OR bimalleolar OR trimalleolar fx
   1. Short-leg posterior splint (ankle at 90o)
   2. Refer within few days for surgical intervention

Disposition

1. Emergent
   1. Open fracture
   2. Fx/dislocation with vascular compromise
   3. Fx/dislocation with significant tenting of the skin
2. Recommended (pt often admitted for repair)
   1. Tillaux/triplane fractures
   2. Intrarticular fractures with displacement
   3. Pilon fractures (reduce if ortho unavailable)
   4. Trimalleolar fractures
   5. Maisonneuve Fx
   6. Any Fx with significant disruption of mortise
3. Recommended (phone is ok)
   1. Bimalleolar Fx
4. Minimally displaced medial or lateral malleolar Fx

Complications

1. Nerve damage
2. Peroneal nerve (lateral ankle injury)
3. Weak foot dorsiflexion
4. Tibial nerve (medial ankle injury)
5. Compartment syndrome
6. Nonunion or malunion
7. Fracture blister/skin necrosis

See Also

• Maisonneuve
• Pilon Fx
• Ottowa Ankle Rules
• Ankle Sprain
• Ankle Fracture (Peds)