Articulations and Movement

1. Articulations and Movement • An articulation or joint is a place where two bones come together. • In terms of the amount of movement they allow, there are three types of joints: • immovable • slightly movable • freely movable.

2. Classes of Joints • Fibrous Joints – Consist of two bones that are united by fibrous connective tissue, have no joint cavity, and exhibit little or no movement. 1. Sutures – are seams between the bones of the skull

3. Cartilaginous Joints – unite two bones by either hyaline cartilage or fibrocartilage. These joints can be slightly moveable due to the flexibility of the cartilage. • Example: symphysis – the symphysis pubis and the intervertebral disks.

4. Synovial Joints –Freely moveable joints.Most joints in the adult body are synovial joints. In this type of joint, the ends of the opposing bones are covered with cartilage and are separated by a space called the joint cavity. The components of the joints are enclosed in a dense fibrous joint capsule. The outer layer of the capsule consists of the ligaments that hold the bones together. The inner layer is the synovial membrane that secretes synovial fluid into the joint cavity for lubrication.

6. Movement • Range of motion – is the amount of movement, active or passive, that can occur at a joint • Types of movement: • Gliding • Angular • Circular

7. Combination • (Special movement) • Gliding movement – Where surfaces slide/glide over each other. Ex. Between carpal bones.

8. Angular movement - * one part of a linear structure, such as the body as a whole or a limb, is bent relative to another part of the structure, thereby changing the angle between the two parts. • Example Flexion and Extension – • Flexion – to bend

9. Extension – to straighten • * relative to the coronal plane. Anterior is flexion and posterior is extension. Ex. Head bending forward is flexion and bending backward is extension

10. (Angular con’t) • Abduction and Adduction • Abduction – meaning to take away – is movement away from the midline • Adduction – meaning to bring together – is movement toward the midline • Example jumping jacks….

11. Circular movements - movement that involves the rotation of a structure along an axis or movement of the structure in an arc. • Example Rotation – turning on the axis – ex. Head • Specific rotations Pronation and supination – the unique rotation of the forearm. Prone means lying facedown, and supine means lying face up

12. Special movements - several ex. Elevation vs. depression (shoulders) and protraction and retraction (jaw) etc…. • Combination movements – movement in the course of normal activity.