Gross Anatomy of a Long Bone

Diaphysis

Shaft of a long bone

Epiphysis

Structure: Expanded knobby. Outer = compact bone. Inner = spongy bone. Articular cartilage of hyaline cartilage covers bone.

Location: the end of a long bone

Function: articulates with another bone

Proximal epiphysis

The end of a long bone closest to the point of origin

Distal epiphysis

The end of a long bone farthest from the point of origin

Compact bone tissue

Structure: Composed of lamellae. Organized into osteons.

Location: outer bone

Function: stability. Protection.

Spongy bone

Structure: composed of trabeculae. Covered by endosteum.

Location: inner layer of bone

Function: protection. Site of hematopoiesis

Medullary cavity

Structure: hollow space

Location: diaphysis of long bones

Function: in adults contains yellow bone marrow

Articular surfaces

Specialized ends of bones that come into contact within a joint.

Function: allow for smooth low friction movements between bones

Epiphyseal line

Structure: bone line

Location: epiphysis of a long bone

Function: remnant of the epiphyseal plate, growth plate

Nutrient foramina

Structure: opening, hole

Location: long bones

Function: opening for blood vessels