- In cats, horses and dogs
- Appear in young animals and stop growing when the bones cease growth
- Defect of skeletal growth
- Possibly inherited in dogs and horses
- Grossly:
- Multiple
- Cartilage capped projections on external surface of bone
- Undergoes endochondral ossification
- Marrow spaces of the masses communicate with the parent bone
- May:
- Interfere with actions of tendons and ligaments
- Cause compression of spinal cord
- Become malignant -> chondrosarcoma
- Seen in adult cats**In flat bones
- Do not undergo endochondral ossification
- Associated with FeLV?
- May also become malignant