Pathogenesis
- Lump of cancellous bone covering cortical bone and a cartilaginous cap
- Originate from separation of small pieces of metaphyseal cartilage from the main cartilagnious epiphyseal plate
- Usually start to grow in adolescence
Approach
- Expose relevant area
- Examine as for lumps
- Inspect
- Hemispherical lump
- Solitary / multiple
- Palpate
- Smooth surface
- Narrow base
- May be bony hard or soft if there is overlying bursa
- Assess relationship with adjacent muscles and tendons
Treatment
- Excision if symptomatic (pressure, cosmesis)
- Suspicion of malignancy
Diaphyseal aclasis
- AD - multiple osteochondromas particularly in the limb bones
- All bones that ossify in cartilage effected except spine and skull
- Thought to be a failure of growth-plate modelling
- Small incidence of sarcomatous change, particularly if subjected to trauma