Exercise 13 - Articulations and Body Movements

decreases the angle of the joint and reduces the distances between the two bones, typical of hinge joints (bending the knee or elbow) and also common in at ball-and-socket joints (bending forward at the hip)

increases the angle of a joint and the distance between two bones or parts of the body (straightening the knee or elbow); if extension is greater than 180 degrees, it's termed hyperextension

movement of a limb away from the midline or median plane of the body

movement of a limb toward the midline of the body or drawing the fingers or toes together

movement of a bone around its longitudinal axis without lateral or medial displacement, a common movement of ball-and-socket joints

a combination of flexion, extension, abduction, adduction commonly observed in ball-and socket joints like the shoulder, condyloid and saddle joints also allow circumduction

movement of the palm of the hand from an anterior, radius rotates over ulna

movement of the palm from a posterior position to anterior position, the radius and ulna are parallel

a movement that results in the medial turning of the sole of the foot

a movement that results in the lateral turning of the sole of the foot

a movement of the ankle joint in a dorsal direction

a movement of the ankle joint in which the foot is flexed downward

to increase cushioning and improve fit

to decrease friction

(linking bone to bone) strengthen joint but stretch only 5-7% of it

covers bone ends to cushion

dense irregular connective tissue, surround the articulation of two adjoining bones

produces a lubricating fluid (synovial fluid) that reduces friction

the clear, viscid, lubricating fluid secreted by synovial membranes.

articulating surfaces are flat or slightly curved, allow only gliding movement as the surfaces slide past one another, ex: intercarparl joints, intertarsal joints, and , and joints between vertebral articular surfaces

the rounded or cylindrical process of one bone fits into the concave surface another bone, allowing movement in one plane, usually flexion and extension, ex: elbow and interphalangeal joints

the rounded surface of one bone articulates with a shallow depression or foramen in another, ex: proximal radioulnar joint

the oval condyle of one bone fits into an ellipsoidal depression in another bone to allow movement in two planes, usually flexion/extension and abduction/ adduction. ex: the wrist and metacarpophalangeal joints

articulating surfaces are saddle shaped; one surface is convex, and the other is concave, permits two movements: flexion/extension and abduction/ adduction. Ex: carpometacarparl joints of the thumb

the ball-shaped head of one bone fits into a cuplike depression of anther bone, permits flexion/extension, abduction/ adduction, and raotation. ex: shoulder and hip joints