A suture 's fibrous connective tissue helps protect the brain and form the face by strongly uniting the adjacent skull bones. Sutures form a tight union that prevents most movement between the bones. Most sutures are named for the bones they articulate.

Why is a suture an immovable joint?

Fibrous joints, such as sutures, syndesmoses, and gomphoses, have no joint cavity. Fibrous joints are connected by dense connective tissue consisting mainly of collagen. Fibrous joints are called “fixed” or “immovable” joints because they do not move.

Which joints are called sutures?

A suture is a type of fibrous joint that is only found in the skull (cranial suture). The bones are bound together by Sharpey's fibres. A tiny amount of movement is permitted at sutures, which contributes to the compliance and elasticity of the skull. These joints are synarthroses.