Fundamentals of Anatomy & Physiology - Joints

Flashcards covering key vocabulary and definitions related to joints, their structure, classification, and movements.

Joints (articulations) Ch 9

Where two bones meet and body movement occurs; a tradeoff exists between strength and mobility.

Structural Joint Classifications

Fibrous, Cartilaginous, Bony, Synovial

Functional Joint Classifications

Synarthrosis (immovable), Amphiarthrosis (slightly movable), Diarthrosis (freely movable)

Synarthrosis

Immovable joint, very strong, edges of bones may touch or interlock, may be fibrous or cartilaginous.

Suture

Synarthrotic joint found only between bones of the skull; edges of bones interlock and are bound by dense fibrous connective tissue.

Gomphosis

Synarthrotic joint that binds teeth to bony sockets via a fibrous connection (periodontal ligament).

Synchondrosis

Synarthrotic joint featuring a rigid cartilaginous bridge between two bones (e.g., vertebrosternal ribs and sternum, epiphyseal cartilage of growing long bones).

Synostosis

Synarthrotic joint created when two bones fuse (e.g., metopic suture of frontal bone, epiphyseal lines of mature long bones).

Amphiarthrosis

A slightly movable joint that is stronger than a diarthrosis; may be fibrous or cartilaginous.

Syndesmosis

An amphiarthrotic joint where bones are connected by a ligament.

Symphysis

An amphiarthrotic joint where bones are connected by fibrocartilage.

Synovial Joints (Diarthroses)

Freely movable joints at the ends of long bones, surrounded by a joint capsule containing a synovial membrane.

Synovial Fluid

Fluid with the consistency of egg yolk, containing proteoglycans, that lubricates, distributes nutrients, and absorbs shock in synovial joints.

Meniscus

Fibrocartilage pad between opposing bones in a synovial joint.

Sprain

Injury to a ligament in a synovial joint involving torn collagen fibers.

Bursae

Small pockets of synovial fluid that cushion areas where tendons or ligaments rub against other tissues.

Monaxial

Movement in 1 plane (e.g., elbow).

Biaxial

Movement in 2 planes (e.g., wrist).

Triaxial

Movement in 3 planes (e.g., shoulder).

Gliding Movement

When two flat surfaces slide past each other (e.g., between carpal bones).

Flexion

Angular movement that decreases the angle between articulating bones.

Extension

Angular movement that increases the angle between articulating bones.

Hyperextension

Extension past anatomical position.

Abduction

Movement away from the longitudinal axis.

Adduction

Movement toward the longitudinal axis.

Circumduction

A complete circular movement without rotation.

Medial (Internal) Rotation

Limb rotation toward the long axis of the body.

Lateral (External) Rotation

Limb rotation away from the long axis of the body.

Pronation

Rotates forearm so that radius rolls across ulna; results in palm facing posteriorly.

Supination

Turns palm anteriorly; forearm is supinated in anatomical position.

Inversion

Twists sole of foot medially.

Eversion

Twists sole of foot laterally.

Dorsiflexion

Flexion at ankle (lifting toes).

Plantar Flexion

Extension at ankle (pointing toes).

Opposition

Movement of thumb toward palm or other fingers.

Reposition

Opposite of opposition.

Protraction

Anterior movement in horizontal plane (forward).

Retraction

Opposite of protraction (pulling back).

Depression

Moving a structure inferiorly (down).

Elevation

Moving a structure superiorly (up).

Lateral Flexion

Bending vertebral column to the side.

Plane Joint (Gliding Joint)

Flattened or slightly curved surfaces; limited motion (nonaxial).

Hinge Joint

Angular motion in a single plane (monaxial).

Condylar Joint

Oval articular face within a depression; motion in two planes (biaxial).

Saddle Joint

Articular faces fit together like a rider in a saddle; biaxial.

Pivot Joint

Rotation only; monaxial.

Ball-and-Socket Joint

Round head in a cup-shaped depression; triaxial.

Intervertebral Disc

Separates vertebral bodies; includes anulus fibrosus (tough outer layer) and nucleus pulposus (elastic, gelatinous core).

Bulging Disc

Bulge in anulus fibrosus that invades vertebral canal.

Herniated Disc

Nucleus pulposus breaks through anulus fibrosus and compresses spinal nerves.

Elbow Joint

Hinge joint involving humerus, radius, and ulna.

Humero-ulnar Joint

Largest, strongest joint at elbow; between trochlea of humerus and trochlear notch of ulna.

Humeroradial Joint

Smaller joint at elbow; articulation between capitulum of humerus and head of radius.

Knee Joint

Complex hinge joint that transfers weight from femur to tibia.

Shoulder Joint (Glenohumeral Joint)

Ball-and-socket diarthrosis between head of humerus and glenoid cavity of scapula; greatest range of motion.

Glenoid Labrum

Rim of fibrocartilage that deepens socket of glenoid cavity in shoulder joint.

Hip Joint

Between head of femur and acetabulum of hip bone; strong ball-and-socket diarthrosis.

Acetabular Labrum

Rim of fibrocartilage that increases depth of joint cavity in hip joint.

Rheumatism

Pain and stiffness in musculoskeletal system.

Arthritis

All rheumatic diseases that affect synovial joints.

Osteoarthritis

Arthritis caused by wear and tear of joint surfaces or genetic factors affecting collagen formation; generally affects people over age 60.

Rheumatoid Arthritis

An inflammatory condition where the immune system attacks joint tissues.

Gouty Arthritis

Arthritis where crystals of uric acid form within synovial fluid.