Extremely uncommon
Stability provided by joint capsule /costoclavicular & interclavicular ligaments
Recurrent instability uncommon
Many apparent dislocations in adolescents may be growth plate injuries
-will remodel without treatment
If OA from chronic dislocation may resect SCJ
Instability in at least 2 planes
- postero-inferior
- antero-inferior
- antero-postero-inferior
Recognised as a common problem
- often misdiagnosed
Most patients athletic
Indications have narrowed
- due to success of shoulder arthroplasty
1. Chronic infections of GHJ
2. Stabilization in paralytic disorders
3. Post-traumatic brachial plexus palsy
4. Salvage of failed GHJ Arthroplasty
- may need bone graft procedures
5. Arthritic diseases unsuitable for arthroplasty / young patient
Post-traumatic (type III clavicle fractures)
Idiopathic
1. OA with osteophytes
- contribute to impingement
2. Osteolysis with resorption & gross osteoporosis
Lateral : Medial 9:1
4th & 5th decades
- M = F
- 75% dominant arm
50% of regular tennis players
- especially > 2 hrs / week
Insertion pathology / Enthesopathy
Over-extension of the elbow with supination / pronation
Lateral epicondyle
- anconeus from posterior face
- ECRB and EDC from anterior face (CEO)
Pain at attachment of thickened central part of plantar aponeurosis to Medial Calcaneal Tuberosity
Origin
- medial calcaneal tuberosity
Inserts
- 5 bands superfical & deep layers
Superficial
- insert transverse MT ligament & skin
Deep
- flexor sheath, volar plate & periosteum of P1