Bone - Terminology

Terminology

Several terms are used to refer to features and components of bones throughout the body:

Bone feature	Definition
articular process	A projection that contacts an adjacent bone.
articulation	The region where adjacent bones contact each other — a joint.
canal	A long, tunnel-like foramen, usually a passage for notable nerves or blood vessels.
condyle	A large, rounded articular process.
crest	A prominent ridge.
eminence	A relatively small projection or bump.
epicondyle	A projection near to a condyle but not part of the joint.
facet	A small, flattened articular surface.
foramen	An opening through a bone.
fossa	A broad, shallow depressed area.
fovea	A small pit on the head of a bone.
labyrinth	A cavity within a bone.
line	A long, thin projection, often with a rough surface. Also known as a ridge.
malleolus	One of two specific protuberances of bones in the ankle.
meatus	A short canal that finishes as a dead end, so it has only the entrance.
process	A relatively large projection or prominent bump.(gen.)
ramus	An arm-like branch off the body of a bone.
sinus	A cavity within a cranial bone.
spine	A relatively long, thin projection or bump.
suture	Articulation between cranial bones.
trochanter	One of two specific tuberosities located on the femur.
tubercle	A projection or bump with a roughened surface, generally smaller than a tuberosity.
tuberosity	A projection or bump with a roughened surface.

Several terms are used to refer to specific features of long bones:

Bone feature	Definition
diaphysis	The long, relatively straight main body of a long bone; region of primary ossification. Also known as the shaft.
epiphysis	The end regions of a long bone; regions of secondary ossification.
epiphyseal plate	Also known as the growth plate or physis. In a long bone it is a thin disc of hyaline cartilage that is positioned transversely between the epiphysis and metaphysis. In the long bones of humans, the epiphyseal plate disappears by twenty years of age.
head	The proximal articular end of the bone.
metaphysis	The region of a long bone lying between the epiphysis and diaphysis.
neck	The region of bone between the head and the shaft.