Ankle fracture

Background

• Always palpate proximal leg to r/o Maisonneuve

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 (Lateral Malleolar)

• Type A
  • Fibular Fx at or below the joint line without syndesmotic involvement
  • Splinting in ED, 6-8 weeks in cast, NWB for three weeks
• Type B
  • Fib Fx at joint level with partial syndesmotic ligament injury
  • Often requires surgical repair
• Type C
  • Fibular Fx above the joint level and complete syndesmotic disruption
  • C-diaphyseal (Dupuytren Fx) or proximal fibular Fx (Maisonneuve)
  • Surgery usually required

Treatment

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

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