Ankle fracture

Physical Exam

• Examine for ecchymoses, abrasions, or swelling
• Note skin integrity and areas of tenderness or crepitus over ankle
• Range joint passively and actively to evaluate for stability
• Examine Joints above and below the ankle
• Perform anterior drawer test (positive exam suggests torn ATFL)
• Always palpate entire length of fibula to rule-out Maisonneuve Fracture (fibulotibialis ligament tear)
  • Perform a crossed-leg test to detect syndesmotic injury
• Evaluate integrity of Achilles tendon (Thompson test)
• Palpate midfoot and base of 5th metatarsal for tenderness

Diagnosis

• Ottawa Ankle Rules
• 3 views:
  • AP
    • Best for isolated lateral and medial malleolar fractures
  • Oblique (mortise)
    • Best for evaluating for unstable fracture or soft tissue injury
    • At a point 1cm proximal to tibial plafond space between tib/fib should be ≤6cm
  • Lateral
    • Best for posterior malleolar fractures

Classification (Danis-Weber System)

System based on level of the fibular fx and characterizes stability of fx

Type A (supination-adduction injury)

• Fibular Fx at or below level of ankle joint (talar mortise) without syndesmotic involvement
• Typically stable
• Deltoid ligament usually intact, medial malleolus usually fx
  • A1: isolated
  • A2: medial malleolus fx
  • A3: posteromedial fx

Type B (supination-external rotation injury)

• Fibular Fx at level of ankle joint (talar mortise) w/ partial syndesmotic ligament injury
• Stability dictated by integrity of tibiofibular syndesmosis (no widening of distal tibiofibular articulation)
• Deltoid ligament may be torn, medial malleolus usually fx
  • B1: isolated
  • B2: medial lesion (either malleolus or ligament)
  • B3: medial lesion and fx of posterolateral tibia

Type C (pronation-eversion injury)

• Fibular Fx above level of ankle joint (talar mortise) w/ complete syndesmotic disruption
• Unstable (widened distal tibiofibular articulation) and require surgical correction
• Deltoid ligament torn, medial malleolus fx
  • C1: simple diaphyseal fibular fracture
  • C2: complex diaphyseal fibular fracture
  • C3: proximal fracture

Management

1. Lateral malleolar Fx (isolated)
   1. Treat like severe ankle sprain unless unstable:
      1. Displacement >2mm
      2. Medial fx
   2. Widening of medial clear space (deltoid injury)
2. Medial or posterior malleolar Fx
   1. Must rule-out other injuries
   2. If non-displaced, isolated:
      1. Short-Leg Posterior Splint (ankle at 90')
      2. Non-weight bearing
      3. Refer in 5-7d
3. Lateral malleolar fx with deltoid injury OR bimalleolar OR trimalleolar fx
   1. Short-Leg Posterior Splint (ankle at 90o)
   2. Immediate consultation in ED

X-rays

Weber A Oblique

Weber B Oblique

Weber B AP

Weber C Oblique

Weber C AP

See Also

• Ankle Sprain
• Ankle Fracture (Peds)
• [[Ottowa Ankle Rules]
• Maisonneuve Fracture
• Pilon Fracture
• Fracture (Main)
• Splinting

Source

• Tintinalli, Radiopaedia.org (Images by Dr. Frank Gaillard), Medpix Radiology Teaching Files (Images by Dr. Timothy Sanders)