talar neck fracture

Talar neck fractures extend through the thinnest cross-sectional portion of the talus, just proximal to the talar head. They represent one of the most common types of talus fracture (~30-50%), along with chip and avulsion fractures of the talus (~40-49%). These fractures are commonly associated with subtalar dislocation and/or posterior body fractures .

Pathology

Mechanism of injury

These fractures usually result from hyperdorsiflexion.

Radiographic features

Plain radiograph

• Canale view (15 degree internal rotation with 15 degree, tube angle (similar tube angle to an AP foot)) demonstrates the fracture well

Classification

Hawkins classification :

• type I: non displaced fracture
• type II: displaced fracture with subluxation or dislocation of the subtalar joint and a normal ankle joint
• type III: displaced fracture with body of talus dislocated from both subtalar and ankle joint

Canale and Kelly  described a rare type IV category which in addition to features described for type III there is dislocation or subluxation of the head of the talus at the talonavicular joint.

Treatment

• type I fractures: short leg cast or boot & no weight bearing
• type II-IV fractures: open reduction - internal fixation (ORIF)

Complications

• hardware complications
  • loosening
  • backing out
  • hardware or peri-hardware fracture
• tendon entrapment or injury
• risk of avascular necrosis (AVN) increases with increasing classification type
  • type I fractures have 0%–15% risk
  • type II fractures have 20%–50% risk
  • type III fractures approach 100% risk
  • type IV fractures have 100% risk

History and etymology

The classification of talar neck fractures was described by Dr Leland G Hawkins in 1970 .

See also

• Hawkins sign

Siehe auch:

• Aseptische Knochennekrose
• Hawkins Zeichen
• Talusfraktur
• Hawkins classification

und weiter:

• ankle radiograph checklist
• Hawkins classification of talar neck fractures