MTPJ dislocation

Epidemiology

Uncommon

- dancers

- athletes

Aetiology

Hyperdorsiflexion of the MTPJ

Pathology

MT head dislocates plantar

- may buttonhole through capsule

- can prevent closed reduction

Blocks to Reduction

1.  Sesamoids

2.  Conjoint tendon

3.  Intersesamoid Ligament

Definition 

Disorder of immune system 

- antigen-antibody complexes

- stimulate release of proteolytic enzymes

- leading to vasculitis, synovitis and cartilage destruction

Characterised

Articular Effects

- synovitis

- ligamentous and capsular laxity

- cartilage destruction

- osseous erosion

Vasculitis

- rheumatoid nodules