Subchondral bone

Epiphysis
Structure of a long bone, with epiphysis labeled at top.
Identifiers
MeSH	A02.835.232.251
Dorlands /Elsevier	12338275
TA	A02.0.00.018
FMA	24012
Anatomical terminology []

The epiphysis (/ɛˈpɪfᵻsᵻs/) 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 bone.

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

There are four types of epiphysis:

There are many bones that contain an epiphysis:

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

Epiphyseal lesions include chondroblastoma and giant-cell tumor.

Long bone

Longitudinal section of head of left humerus.