Musculoskeletal System - Joint Development
From Embryology
Introduction
In the adult, the region where two skeletal bones meet and articulae is called a "joint".
In the adult, there are a range of adult joint types based upon their anatomical structure, mobility and shape of the joint.
In the embryo, the majority of the vertebrate skeleton is initially formed as a cartilage template, that is later replaced by bone except at the interface between two adjacent bones, leaving in the adult a layer of cartilage in this region. The musculoskeletal system consists of skeletal muscle, bone, and cartilage and is mainly mesoderm in origin with some neural crest contribution.
Joint Types
Classification
- Fibrous (synarthrodial) - immoveable joints found in cranial vault and teeth
- Cartilagenous (synchondroses and sympheses) - partially moveable joints
- Synovial (diarthrosis) - freely moveable joints are the most common found in the skeleton
Movement
- Hinge - (elbow and knee) Flexion/Extension
- Pivot - (neck, atlas and axis bones) Rotation of one bone around another
- Ball and Socket - (shoulder and hip)
- Saddle - (thumb)
- Condyloid - (wrist joints)
- Gliding - (intercarpal joints) Gliding movements
