presentation

Epidemiology

Rare

- ? dislocates in utero or post-natal period

Usually bilateral

Aetiology

Familial

Associated with Down's / Larsen's & Arthrogryposis

Pathology

Persistent lateral patella dislocation

- hypoplastic flat LFC

- aberrant lateral insertion quadriceps

- hypoplastic flat patella

Definition 

A chronic systemic, autoimmune inflammatory disease of unknown cause

Epidemiology

1% of population

M:F = 1:3

Peak onset 40 years

Most common inflammatory arthropathy

Aetiology

Autoimmune

- trigger not identified

- cell mediated immune response