Epiphysis

The epiphysis is the rounded end of a long bone, at its joint with adjacent bone(s). Between the epiphysis and diaphysis (the long midsection of the long bone) lies the metaphysis, including the epiphyseal plate (growth plate). At the joint, the epiphysis is covered with articular cartilage; below that covering is a zone similar to the epiphyseal plate, known as subchondral bone (see subchondral).

The epiphysis is filled with red bone marrow, which produces erythrocytes (red blood cells).

Pathology
Pathologies of the epiphysis include avascular necrosis and osteochondritis dissecans (OCD). OCD involves the subchondral bone.

Epiphyseal lesions include chondroblastoma and giant-cell tumor.