A synchondrosis (or primary cartilaginous joint) is a type of cartilaginous joint where hyaline cartilage completely joins together two bones.^[1] Synchondroses are different from symphyses (secondary cartilaginous joints) which are formed of fibrocartilage. Synchondroses are immovable joints and are thus referred to as synarthroses.are all synchondroses synarthrotic/immovable^{[citation needed]}

Synchondrosis
Sagittal section through the clivus of the skull demonstrating the location of the spheno-occipital synchondrosis in an infant.
Identifiers
TA98	A03.0.00.016
TA2	1529
FMA	7497
Anatomical terminology [edit on Wikidata]

Examples in the human body

Permanent synchondroses

• first sternocostal joint (where first rib meets the manubrium of the sternum)
• petro-occipital synchondrosis

Temporary synchondroses (fuse during development)

• epiphyseal plates
• apophyses
• synchondroses in the developing hip bone composed of the ilium, ischium and pubis
• spheno-occipital synchondrosis