Anatomy & Physiology: Joints & Articulations

Flashcards covering the classification, structures, specific examples, and movements of joints based on lecture notes.

Joint (Articulation)

The location where two bones come together, bone and cartilage connect, or a bone and a tooth meet.

Synarthrosis

A functional classification of a joint that is described as immovable or nearly immovable.

Amphiarthrosis

A functional classification of a joint that is slightly movable, providing stability and limited flexibility.

Diarthrosis

A functional classification of a joint that is freely movable; all synovial joints fall into this category.

Fibrous Joint

A structural classification where adjacent bones are united by fibrous connective tissue and lack a joint cavity.

Cartilaginous Joint

A structural classification where bones are connected by hyaline cartilage or fibrocartilage.

Synovial Joint

A structural classification where bones are separated by a fluid-filled joint cavity, allowing the greatest range of movement.

Uniaxial Joint

A diarthrosis that allows movement in only one plane, such as the elbow joint.

Biaxial Joint

A diarthrosis that allows movement in two planes, such as the metacarpophalangeal (knuckle) joints.

Multiaxial Joint

A diarthrosis that allows movement in all three anatomical planes, such as the shoulder and hip joints.

Suture

A type of fibrous joint (synarthrosis) that connects the bones of the skull, except for the mandible.

Synostosis

The process by which connective tissue or cartilage between bones ossifies and fuses completely into bone.

Fontanelles

Wider areas of connective tissue between skull bones in infants that allow for flexibility during birth and rapid brain growth.

Syndesmosis

A fibrous joint (amphiarthrosis) where parallel bones are joined by ligaments or an interosseous membrane, such as between the radius and ulna.

Gomphosis

A specialized fibrous joint (synarthrosis) also known as a peg-and-socket joint that anchors a tooth into its jaw bone socket via the periodontal ligament.

Synchondrosis

A cartilaginous joint (synarthrosis) where bones are connected by hyaline cartilage, such as the epiphyseal plate or the first sternocostal joint.

Symphysis

A cartilaginous joint (amphiarthrosis) where bones are connected by fibrocartilage, such as the pubic symphysis and intervertebral discs.

Articular Capsule

The fibrous connective tissue structure that surrounds a synovial joint and encloses the joint cavity.

Synovial Fluid

The fluid secreted by the synovial membrane that lubricates the joint, reduces friction, and nourishes the articular cartilage.

Bursae

Fluid-filled sacs located between tissues that reduce friction and facilitate smooth movement.

Pivot Joint

A type of synovial joint that allows rotation around a central axis, such as the atlantoaxial joint between C1 and C2.

Hinge Joint

A synovial joint that allows movement in one plane (flexion and extension), such as the humeroulnar joint of the elbow.

Condyloid Joint

A synovial joint that allows flexion/extension and abduction/adduction, such as the radiocarpal joint of the wrist.

Saddle Joint

A synovial joint where articulating surfaces are both concave and convex, allowing biaxial movement and opposition; found at the first carpometacarpal joint of the thumb.

Plane Joint

A synovial joint that allows gliding movements (back and forth, side to side), such as intercarpal joints.

Ball-and-Socket Joint

A multiaxial synovial joint allowing flexion/extension, abduction/adduction, rotation, and circumduction; found at the shoulder and hip.

Flexion

A movement in the sagittal plane that decreases the angle between body parts.

Extension

A movement in the sagittal plane that increases the angle between body parts.

Abduction

Movement in the frontal plane that moves a body part away from the midline of the body.

Adduction

Movement in the frontal plane that moves a body part toward the midline of the body.

Circumduction

A circular movement combining flexion, extension, abduction, and adduction so the distal end of a part moves in a circle.

Supination

Turning the forearm and hand so the palm faces up or anteriorly.

Pronation

Turning the forearm and hand so the palm faces down or posteriorly.

Dorsiflexion

Movement at the ankle joint where the foot moves upward toward the shin.

Plantarflexion

Movement at the ankle joint where the foot moves downward, such as pointing the toes.

Inversion

Turning the sole of the foot inward toward the midline of the body.

Eversion

Turning the sole of the foot outward away from the midline of the body.

Opposition

The thumb movement across the palm to touch the fingertips of other fingers.

Glenohumeral Joint

The shoulder joint; a ball-and-socket synovial joint formed between the head of the humerus and the glenoid cavity of the scapula.

Acetabular Labrum

A fibrocartilage lip that deepens the acetabular socket of the hip joint to improve stability.

Anterior Cruciate Ligament (ACL)

A knee ligament that prevents the tibia from sliding too far forward and resists hyperextension.

Talocrural Joint

The joint that forms the ankle, involving the talus, tibia, and fibula.

Mesenchyme

The embryonic tissue from which all bones, cartilage, and connective tissues of joints develop.

Joint Interzone

The specific region in a developing limb where cells die to create the synovial joint cavity.