techniques

Etiology

Ankle sprain

- eversion / external rotation

Ankle fractures

Types

1.  Standard trochanteric osteotomy

2.  Sliding trochanteric osteotomy

3.  Extended trochanteric osteotomy

Standard Trochanteric osteotomy

Advantage

1.  Reduce implant loosening

- offset load sharing to diaphysis

- 30% if > 70 mm

2. Restore optimal alignment

Indications

1.  Using augments or bone grafting

2.  Increased constraint 

- VVS / hinge

Definition

Patients usually complain of subluxation rather than dislocation

- rarely requires reduction

Different entity to acute posterior dislocation usually

Epidemiology

Rare

Aetiology

1.  Ligamentous laxity > 50%

- commonly associated with MDI

- posterior only 20%

- posterior & inferior 20%

Definition

Instability in at least 2 planes

- postero-inferior

- antero-inferior

- antero-postero-inferior

Epidemiology

Recognised as a common problem 

- often misdiagnosed

Most patients athletic

Epidemiology

Dominant arm of middle aged men

- between 40 and 60

Aetiology

Sudden dramatic event

- sporting / weightlifting injury

- resisting heavy extension load

Pathology

Degenerative changes seen on histology

Types

Complete

- retracted / rupture of lacertus fibrosis

- minimally retracted