Anatomy and Physiology

Synarthrosis

Immovable joint.

Amphiarthrosis

Slightly movable joint.

Diarthrosis

Freely movable joint.

Synostosis

Body joint; complete fusion of bones across a structure line.

Syndesmosis

Greater distance between the articulating bones and more fibrous connective tissue.

Symphysis

Cartilaginous joint connected by a disc of fibrocartilage.

Synchondrosis

Cartilaginous joint in which the connecting material is hyaline cartilage.

Gomphosis

Cone-shaped peg fits into a socket; dento-alveolar joint.

Fibrous

No synovial cavity; held together by fibrous connective tissue rich in collagen fibers.

Cartilaginous

No synovial cavity; held together by cartilage.

Synovial

Has a synovial cavity; united by articular cartilage; often includes ligaments.

Periodontal ligaments

Hold teeth in jaw socket.

Sutures

Thin layer of dense, fibrous connective tissue uniting only the bones of the skull.

Epiphyseal plate

Layer of cartilage present only during the growth period and vanishes soon after puberty in long bones.

Epiphyseal line

An epiphyseal plate that has become ossified.

Typical Synovial Joint Structure

Two bony surfaces that are encompassed by a fibrous capsule with a synovial lining.

Accessory Synovial Joint Structures

Articular discs or menisci.

Ligaments

A short band of tough, flexible fibrous connective tissue which connects two bones or cartilages or holds together a joint.

Tendons

Connect muscle to bone; provide mechanical support; may limit range of motion.

Aponeurosis

Flat sheets of connective tissue.

Bursa

Small, fluid-filled sac that lies near bony prominences and joints.

Menisci

C-Shaped pad of cartilage in the knee that acts as a shock absorber.

Articular Cartilage Characteristics

Shock absorber and reduces friction.

Synovial Fluid Characteristics

Reduces friction and lubricates joint.

Types of Synovial Joints

Hinge, pivot, saddle, ball and socket, gliding, ellipsoid.

Flexion

Decreasing the angle between articulating bones.

Extension

Increasing the angle between articulating bones.

Hyperextension

Extension past neutral.

Abduction

Movement of a bone away from the midline.

Adduction

Movement of a bone toward the midline.

Medial Rotation

Internal/Inward rotation of a body part.

Lateral Rotation

External/Outward rotation of a body part.

Eversion

Turning soles of the feet away from midline.

Inversion

Turning soles of the feet toward the midline.

Plantarflexion

Standing on toes.

Dorsiflexion

Standing on heels.

Supination

Palms turned upward.

Pronation

Palms turned downward.

Elevation

Upward movement of a body part.

Depression

Downward movement of a body part.

Lateral Flexion

Side Bending.

Circumduction

A series of movements with no rotation.

Opposition

Thumb touching fingers.

Reposition

Thumb returns to anatomical position.

Protraction

Movement away from the midline.

Retraction

Movement toward the midline.