Joints & Joint Movement - VS 101

Vocabulary flashcards defining joint classifications, synovial fluid, tendons, ligaments, types of joint movement, and categories of synovial joints.

Fibrous Joints (Synarthroses)

Immovable joints united firmly by dense fibrous connective tissue (e.g., skull sutures, gomphosis of teeth).

Cartilaginous Joints (Amphiarthroses)

Slightly movable joints united by hyaline cartilage or fibrocartilage, acting as shock absorbers (e.g., pelvic symphysis, mandibular symphysis, intervertebral discs).

Synovial Joints (Diarthroses)

Freely movable joints characterized by a joint cavity, articular cartilage, a surrounding fibrous capsule lined by a synovial membrane, and lubricated by synovial fluid (e.g., stifle, shoulder, hip).

Synovial Fluid

A viscous, clear fluid rich in hyaluronic acid and lubricin, secreted by the synovial membrane. It lubricates joint surfaces to eliminate friction, absorbs mechanical shock during weight-bearing, and nourishes non-vascularized articular cartilage.

Tendon

Tough, fibrous connective tissue band that attaches muscle to bone.

Ligament

Fibrous connective tissue band that attaches bone to bone across a joint to provide structural stability.

Abduction

Moving a limb away from the medial plane of the body.

Adduction

Moving a limb toward the medial plane of the body.

Circumduction

Motion where the distal end of an extremity moves in a circle while the proximal end remains stationary.

Extension

Increasing the angle between two bones at a joint.

Flexion

Decreasing the angle between two bones at a joint.

Rotation

Twisting motion of a part around its longitudinal axis.

Ball-and-socket joint (Spheroidal)

A type of synovial joint exemplified by the hip joint (coxofemoral) and shoulder joint (scapulohumeral).

Gliding joint (Arthrodial)

A type of synovial joint exemplified by carpal joints (intercarpal) and tarsal joints (intertarsal).

Hinge joint (Ginglymus)

A type of synovial joint exemplified by the elbow joint (humeroulnar/humeroradial) and fetlock joint.

Pivot joint (Trochoid)

A type of synovial joint exemplified by the atlantoaxial joint ($C1-C2$) and proximal radioulnar joint.