In anatomy, the term “articulation” refers to a complex of structures that maintains two or more bone surfaces in contiguity .The joint is therefore a set of elements (fibrous and / or cartilage tissue, ligaments, capsules, membranes) that regulate the connection between two skeletal segments .
What are joints?
The bone heads that make up the joints can be, among them:
- Furniture (such as hip , knee , ankle , wrist, shoulder and elbow )
- Semi-movable (such as the spine joint)
- Fixed (as in the case of the joints of the bones of the skull or pelvis)
This depends on whether they serve to originate more or less wide movements or to stable anchoring mechanisms : using scientific terminology we speak – respectively – of diarthrosis, amphiarthrosis and synarthrosis .
What are the fixed joints?
Also called “synarthrosis” , they are those that confer stability : for example, the joints of the bones of the skull and pelvis are such . They are characterized by the continuity of the bone segments that compose them, between which portions of fibrous, bone or cartilaginous tissue are interposed; do not allow the execution of movements.
What are the moving joints?
Also called “diarthrosis” , they are those in charge of the movement. They consist of a complex mechanism that allows their mobility : those of the knee and elbow are considered such .
What are the semi-mobile joints?
Also called “amphiarthrosis” , they are characterized by limited movements: the joint of the vertebral column is considered semi-mobile .
What are joints used for?
Their main function is to give stability to some parts of the body (as happens, for example, in the case of the skull and pelvis).
Those semi-movers, in addition to allowing the realization of certain movements, also act as support structures .
The main function of the mobile ones is to allow the execution of wide movements , as in the case of the knee or elbow joint: the articular surfaces that form them can have various shapes – flat, spherical, ellipsoidal – and are usually ” concordant ” , that is, one embraces the other, precisely to allow a wide range of movements.
- Fixed joints
- Movable joints
- Semi-mobile joints