investigation

Incidence

Dale et al Acta Orthop 2012

- Nordic Arthroplasty Registry of 430,000 THA

Anatomy

3 primary stabilizers (plus posterolateral capsule)

LCL / Popliteus / Popliteofibular ligament

Laprade et al. AJSM 2003

https://pubmed.ncbi.nlm.nih.gov/14623649/

1.  Lateral collateral ligament

Femoral attachment

Definition

Proximal Focal Femoral Deficiency

- congenital malformation

- characterised by failure of normal development of the proximal femur

Epidemiology

Rare

- 1 in 50 000

Bilateral in 15% 

- usually more severe

Association

Fibular hemimelia in 2/3

ACL deficient

Epidemiology

70% male

70% positive FHx

20% learning difficulties

DDx toe walking

Early / late onset

Unilateral  / bilateral

1.  Habitual

Toddlers - child can heel walk

2.  Structural

Fixed equinus - CTEV / arthrogryposis

Short / tight T Achilles

Space occupying lesion in calf