ORIF Talar Neck Fracture

Aims, Principles & Alternatives

  • Aim to urgently reduce & fix displaced fractures
  • AVN risk correlates with severity of displacement, & delay in reduction leads to skin necrosis & infection
  • Alternative
    • BKPoP 8 – 12 weeks
      • undisplaced, or minimal displacement
      • poor surgical candidate

Indications

  • Displaced Talar neck fracture
    • with/out
      • dislocation of subtalar
      • ankle
      • talo-navicular joints
    • Even if body completely extruded, replace & maintain limb length unless severely contaminated or comminuted.
    • If excising body, can do tibio-calcaneal fusion, or spanning ex-fix & delayed Blair fusion or tibio-calcaneal fusion with interposition graft

Contraindications

  • Entirely undisplaced fracture
  • Minimally displaced fracture
    • elderly
    • neuropathic
    • diabetic
    • PVD

Preop Planning

  • Xray
    • AP/lateral /obl of ankle & foot
  • CT
    • if unsure of subtle displacement or loose bodies in subtalar joint
  • Consent including
    • AVN, skin breakdown, infection, subtalar/ankle arthritis

Technique

  • Attempt urgent closed reduction, but often unsuccessful
  • GA, supine, IV anti’s, tourniquet, prep & drape
  • Medial approach ± medial malleolar osteotomy
    • 10 cm incision from medial malleolus extending anteriorly & toward sole of foot, ending on medial side of navicular, in plane between Tibialis anterior & posterior. Avoid tendoneurovascular bundle below medial malleolus
    • If talar body is extruded from ankle mortise, a medial malleolar osteotomy may assist in exposure & reduction (predrill screw holes). Expose fracture & anteromedial neck but preserve as much soft tissue attachment as possible. Reduce fracture & irrigate joint to remove debris
  • anterolateral approach
    • is often useful to assess reduction & allow insertion of 2nd screw. Make a 5 cm incision over sinus tarsi extending toward base of 4th MT
    • Preserve cutaneous nerve branches & incise inferior extensor retinaculum. Reflect EDB & expose fracture
  • Reduce, avoiding varus
  • Temporarily fix with K wires, then insert cannulated screws (4.0 or 6.5 mm) anterior to posterior, one medial, one lateral & countersunk, just behind articular surface
  • Check with II
  • (Alternative is posterior to anterior screws from lateral to tendo Achilles, in interval between FHL & peroneal tendons)

Fix medial malleolus, close wounds.

Postop

  • BKPoP 6-8 weeks
  • Xray OOP to check for union & Hawkins sign
  • If uniting, walking cast / CAM walker 6 weeks. Then shoe with scaphoid pad for 3 months

Results

Hawkins (1970):

  • I 100% union, 0% AVN
  • II 100% union, 42% AVN
  • III 89% union, 91% AVN

Canale & Kelly defined type IV fractures (100% AVN), & found low incidence of AVN in type I fractures.

Keeping patient NWB if AVN does not prevent collapse. Painful AVN may require debridement of necrotic bone & Blair fusion.

Complications

  • General systemic
  • General local
    • skin necrosis, infection, DVT, neurovascular injury
  • Specific
    • post traumatic arthritis (even after undisplaced fracture), AVN, varus malunion