5-15% of posterior dislocations
Posterior hip dislocation
Type I - head fracture below fovea
Undisplaced
- non operative
Displaced
- excise fragment if small
- ORIF fragment if large (can contribute to instability)
Posterior Portal
- make slightly inferior and lateral compare to normal
- inspect joint
Hyperextension of MTPJ and PIPJ / DIPJ flexion
- usually all toes affected
1. Complex hammer
- hammer toe with MTPJ extension
- hammer usually affects second toe
2. Curly toe
Able to achieve relatively high level of function after STJ fusion
- previously believed that isolated STJ fusion should not be performed
- believed that triple arthrodesis was operation of choice for hindfoot
- STJ fusion has superior result with less stress on AJ
Average loss of DF 30% / PF 10%
Position of hindfoot determines flexibility of transverse tarsal (CCJ & TNJ) joints
- imperative that fusion be positioned in ~ 5o valgus
FOOSH
- axial load with a valgus force
1. Provides Valgus stability
- especially if MCL deficient
2. Longitudinal stability
- aided by interosseous membrane
3. Load Transfer
- 60% of load at elbow
THR in dysplastic hips has a higher failure rate
- due to anatomic abnormalities
- due to generally younger age
Restore normal biomechanics and preserve bone stock
Soft tissues
Chronic instability due to rupture of one or more parts of the lateral ligament
Progressive injury
1. Anterolateral capsule
2. ATFL
3. CFL
Can lead to ankle OA over time
