Definition
Involvement epiphysis or apophysis of immature skeleton
- heterogenous group of eponymous conditions
- usually occurs at time of greatest growth
Xray
Features of
- sclerosis
- fragmentation
- decrease in size of ossification centre
NHx
Some progress to OA
Some are self-healing
Pathology
Affected portion of bone has features of osteonecrosis
Thought to be due to recurrent minor trauma & avascularity
Three types
Crushing
Types
- Kohler's (4 year old boys)
- Freiberg's (11 year old girls)
- Panner's (young child or teens)
- Kienbock's (20-30 years)
Pathology
Spontaneous necrosis of
- ossific nucleus of long bone
- cuboidal bone of wrist or foot
Pathological changes of AVN
- bone death
- fragmentation
- collapse
- new bone formation
Pulling
Types
- Osgood-Schlatter
- Sever's
- Sinding-Larsen-Johansson
- Menalaus-Batten
Aetiology
Excessive traction by large tendon to unfused apophysis
- repetitive microtrauma
- no bone necrosis
- apophysis becomes painful
- may be tenosynovitis
Splitting
OCD of Knee / Ankle / Hip
Uncertain aetiology but thought to be combination of microtrauma & hypovascularity