Articulations and Range of Motion
dorsiflexion
Lifting the foot so that its superior surface approaches the shin (corresponds to wrist extension)
Protraction
Nonangular anterior movements in a transverse plane
Retraction
Nonangular posterior movements in a transverse plane
plantar flexion
depressing the foot (pointing the toes)
supination
Rotating the forearm laterally so that the palm faces anteriorly or superiorly
Flexion
a bending movement, usually along the sagittal plane, that decreases the angle of the joint and brings the articulating bones closer together.
epiphyseal (growth) plate
a disc of hyaline cartilage that grows during childhood to lengthen the bone
Joint Cavity
a feature unique to synovial joints; a potential space that contains a small amount of synovial fluid
periosteum
a glistening white, double-layered membrane that covers the external surface of the entire bone except the joint surfaces
synovial
articulating bones are separated by a fluid-filled cavity. Most joints are this way. Examples: gliding, condyloid, ball-and-socket, hinge, saddle, pivot
epiphysis
bone ends
synchondroses
cartilaginous; joints between the shafts and the epiphyseal plates of long bones
symphyses
cartilaginous; pads of fibrous cartilage cushions joint Examples: pubic symphysis, intervertebral joints
articular cartilage
covers the ends of most bones at movable joints
sutures
fibrous; b/w bones of skull (in adults, fibrous tissue ossifies creating synostoses)
syndesmoses
fibrous; junction of bones held together by ligaments Examples: tibia-fibula; radius-ulna; (distal ends)
gomphoses
fibrous; tooth attached to socket with periodontal ligament
diarthroses
freely movable joints
synarthroses
immovable joints
Abduction
movement of a limb away from the midline or median plane of the body, along the frontal plane
Circumduction
moving a limb so that it describes a cone in space; distal end of the limb moves in a circle, while the point of the cone (the shoulder or hip joint) is more or less stationary
Extension
reverse of flexion and occurs at the same joints; involves movement along the sagittal plane that increases the angle between the articulating bones and typically straightens a flexed limb or body part
diaphysis
shaft that forms the long axis of the bone, composed of a relatively thick collar of compact bone
amphiarthroses
slight movable joints
pronation
the forearm rotates medially and the palm faces posteriorly or inferiorly.
Adduction
the opposite of abduction, so it is the movement of a limb toward the body midline or, in the case of the digits, toward the midline of the hand or foot
Rotation
the turning of a bone around its own long axis
synovial fluid
viscous, egg-white consistency; provides slippery, weight-bearing film that reduces friction b/w the cartilages
meniscus (articular disc)
wedges of fibrocartilage separating the articular surfaces