Hip Dislocation
Incidence
Young men
Posterior / Anterior 9:1
Aetiology
High velocity injury
- head direction at impact decides direction of dislocation
Anterior Dislocation
Externally rotated & abducted leg
- flexion = inferior dislocation

Young men
Posterior / Anterior 9:1
High velocity injury
- head direction at impact decides direction of dislocation
Anterior Dislocation
Externally rotated & abducted leg
- flexion = inferior dislocation
CP is a permanent disorder of movement and posture
- non-progressive
- brain injury before the age of two years
Strict definition excludes familial & progressive congenital problems & those acquired in childhood as a result of head injuries
2-3 per 1000 live births
Higher in

Up to 8% patients with ACL reconstruction will have recurrent instability and graft failure
- increased with surgical inexperience
1. Be inadequate from the start
- inadequate tension
- poor tunnel placement
Virchow's Triad
1. Venous stasis
2. Hypercoagulability
3. Endothelial damage
Starts as platelet nidus at valves
- thrombogenic materials elaborated by platelets
- leads to development of fibrin thrombus
- thrombus grows
Thrombus may
- detach as embolus
- be completely dissolved / recanalise
- organise with valve incompetence
Self limiting syndrome of unknown aetiology
- hip pain associated with osteoporosis of proximal femur
AVN
- AVN of the hip in pregnancy is rare but possible
- TOH tends to be diffuse on MRI, while AVN is localised
- extends to neck and metaphysis
- transient osteoporosis has normal bone scan
Rare
- M: F 3:1
Largely related to degree of displacement
Hawkins Type I
- 0% to 13%

Hawkins Type II
- 20% to 50%
- usually only patchy and not a problem (rarely collapses)
Dorsal
- most common
Volar
1. Acute traumatic peripheral tear TFCC with DRUJ dislocation
- usually major trauma
- dorsal or volar
2A. Distal radial fracture
Pain & Stiffness
- often more pain than FT tears
Bursal side tears more painful than articular
Articular side more common
May see in young patient overhead throwing
Painful arc
Impingement signs
No weakness
- function good
10% of elbow tendonitis
Overuse injury
- poor swing in golf
- poor throwing technique
- overuse of topspin in tennis
- occupational (repetitive hammering / screwing)
Some patients also have lateral epicondylitis
Tenderness CFO
Stimulate pain
- flexion of WJ with fingers resisting
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)