Aetiology
- Most unknown but several inherited forms are described – autosomal dominant
Multiple Associated Anomalies
- Split hand & foot
- Syndactyly
- Polydactyly
- Five fingered hand
- Finger anonychia
- Bifid femur
Classification
| Type | Description |
|---|---|
| 1 | Tibia not seen at birth |
| 1a | upper tibia not present |
| 1b | upper tibia is late to ossify |
| 2 | Proximal tibia ossified, distal tibia absent |
| 3 | Distal tibia is ossified, proximal tibia absent |
| 4 | Congenital Diastases of the ankle |
Treatment
Complete
- knee disarticulation
- Generally no Brown procedure – centralize the fibula
Incomplete
- IB may be able to fuse the proximal to the upper tibia & save knee if the quad is present – if not salvageable then through knee amputation
- Type II – upper tibia present, fuse fibula to tibia leaving a functional knee, distal Symes amputation secondary to ankle instability
- Type IV – modified Symes amputation