Mnemonic: NISA 10-50-90-100
Type I – Non-displaced Neck fracture (upto 10% risk of AVN)
- 1 blood vessel damaged (entering talar neck)
- Management: 8 weeks in cast and 4 weeks in CAM cast
Type II – Type I + Inferior (subtalar) subluxation/dislocation (upto 50% risk of AVN)
- 2 blood vessels damaged
- Management: Immediate closed reduction and management as type I
Type III – Type II + Superior (tibiotalar) subluxation/dislocation (90% risk of AVN)
- 3 (all sources) blood vessels damaged
- Management: ORIF using combined anterolateral and anteromedial approach
Type IV – Type III + Anterior (talonavicular) subluxation/dislocation (100% risk of AVN)
- AVN not related to blood supply damage
- Management: As type III
He is the section editor of Orthopedics in Epomedicine. He searches for and share simpler ways to make complicated medical topics simple. He also loves writing poetry, listening and playing music.