A&P Ch 9

Inversion

movement of the soles medially at the intertarsal joints so that they face away from each other

Articular cartilage

Covers bones at synovial joints. The articular cartilage reduces friction at the joint with movement and helps absorb shock.

Articular capsule

Surrounds a diarthrosis, encloses the synovial cavity, and unites the articulating bones. Composed of two layers - the outer fibrous capsule (which may contain ligaments) and the inner synovial membrane (which secretes a lubricating and joint-nourishing synovial fluid). The flexibility of the fibrous capsule permits considerable movement at a joint, whereas its great tensile strength helps prevent bones from dislocating. Synovial fluid, secreted by the synovial membrane, lubricates and reduces friction in the joint and supplies nutrients to and removes metabolic wastes from the joint.

Rotation

a bone revolves around its own longitudinal axis. Pivot and ball-and-socket joints permit rotation.

Symphyses

a cartilaginous joint in which the connecting material is a disc of fibrocartilage, allowing some movement. Examples are the intervertebral discs and the pubic symphysis.

Synchondroses

a cartilaginous joint in which the connecting material is hyaline cartilage, allowing no movement.

Hyperextension

a continuation of extension beyond the anatomical position and is usually prevented by the arrangement of ligaments and the anatomical alignment of bones.

Depression

a downward movement of a part of the body

interosseous membranes

a fibrous joint made of a broad sheet of ligament that allows some movement between adjacent bones. An example is between the radius and ulna

Protraction

a movement of a part of the body anteriorly in the transverse plane

Retraction

a movement of a protracted part back to the anatomical position

Pronation

a movement of the forearm at the proximal and distal radioulnar joints in which the distal end of the radius crosses over the distal end of the ulna and the palm is turned posteriorly or inferiorly

Supination

a movement of the forearm at the proximal and distal radioulnar joints in which the palm is turned anteriorly or superiorly. Holding soup in hands.

Eversion

a movement of the soles laterally at the intertarsal joints so that they face away from each other

Pivot joint

a round or pointed surface of one bone fits into a ring formed by another bone and a ligament. Movement is rotational and monaxial. An example is the atlas rotating about the axis.

Sutures

a suture is a fibrous joint composed of a thin layer of dense fibrous connective tissue that unites skull bones. A synostosis is a suture joint that has ossified. An example of a synostosis is the frontal suture between the left and right sides of the frontal bone. A synostosis is functionally classified as a synarthrosis.

Condyloid joint

an oval-shaped condyle of one bone fits into an elliptical cavity of another bone. Movements are flexion-extension, abduction-adduction, and circumduction; an example is the joint between the carpals and the radius

Elevation

an upward movement of a part of the body

Structural classification

based on the presence or absence of a synovial (joint) cavity and type of connecting tissue. Structurally, joints are classified as fibrous, cartilaginous, or synovial.

Dorsiflexion

bending of the foot at the ankle in the direction of the superior surface

Plantar flexion

bending of the foot at the ankle joint in the direction of the plantar surface

Hinge joint

contains the convex surface of one bone fitting into a concave surface of another bone. Movement is primarily flexion or extension in a single plane. Examples include the elbow, knee, ankle, and interphalangeal joints

Synovial joints

have a synovial cavity. Articulating bones are covered with articular cartilage, held together by ligaments, contain synovial fluid, have a nerve and blood supply, and are surrounded by an articular capsule. Permit a large range of movement. structure...

Lateral flexion

involves the movement of the trunk sideways to the right or left at the waist. The movement occurs in the frontal plane and involves the intervertebral joints.

Osteoarthritis

is a degenerative form, like wear and tear. Deterioration of articular cartilage. Bone spur formation. Non inflammatory. Weight bearing joints.

Fibrous joints

lack a synovial cavity. Are articulating bones are held together with dense fibrous connective tissue. Permit little or no movement. sutures, syndesmoses, interosseous membranes

Cartilaginous joints

lack a synovial cavity. Articulating bones are held together with cartilage connective tissue. Permit little or no movement.

Plain joints

permit mainly side-to-side and back-and-forth gliding movements.These joints are nonaxial and include the intercarpal, intertarsal, sternoclavicular, acromioclavicular, sternocostal, and vertebrocostal joints.

Rheumatoid arthritis

refers to any painful state of the supporting structures of the body )bones, ligaments, tendons, muscles). Autoimmune attacks itself and its own joints. Loss of joint function. Arthritis is a form of RA. Inflammation of joint. Ulnar deviation. Normally bilateral.

Circumduction

refers to movement of the distal end of a part of the body in a circle. Condyloid, saddle, and ball-and-socket joints allow circumduction.

Abduction

refers to the movement of a bone away from the midline

Adduction

refers to the movement of a bone toward the midline

Flexion

results in a decrease in the angle between articulating bones.

Extension

results in an increase in the angle between articulating bones.

Syndesmoses

s a fibrous joint in which there is more fibrous connective tissue than in a suture. Gomphosis is the root of a tooth.

Opposition

the movement of the thumb at the carpometacarpal joint in which the thumb moves across the palm to touch the tips of the finger on the same hand