Joints

Synchondroses

Structurally cartilagenous joint with hyaline cartilage, found temporarily in epiphyseal plates, permanently in costal cartilage (Functionally synarthroses - immovable)

circumduction

circular movement of joint, combining movements; possible in shoulder joint, hip joint, and trunk around a fixing point

articular cartilage

covers the surfaces of bones where they come together to form joints

axis of rotation

imaginary line or point about which an object such as a body or a lever, rotates

sutures

immovable joints in the skull

symdesmoses (fiber joint)

is a fibrous joint at which two bones are bound by longer collagenous fibers than in a suture or gumphosis, giving the bone more mobility

Symphses

jointed by fibrouscartilage

abduction

moving of a body part AWAY from the central axis of the body

lap suture

occurs when two bones have overlapping beveled edges

plane sutures

occurs when twoo bones have straight nonoverlapping edges.

bony joint

or synostosis; an immovable joint formed when the gap between two bones ossifies and they become, in effect, a single bone. it can be form by ossification of either fibrous or cartilaginous joints

pronation

rotation of the hands and forearms so that the palms face downward

supination

rotation of the hands and forearms so that the palms face upward

extension

straightening at the joint so that the angle between the bones is increased

tendon

strong connective tissue that attaches muscle to bone

ligament

strong connective tissue that holds bones together in movable joints

Gompohoses (fiber joint)

the attachment of tooth as a joint is called ------------

mechanical advantage

the ratio of the output force to the input force

synovial fluid

viscid lubricating fluid secreted by the membrane lining joints and tendon sheaths etc. It's rich in albumin and hyaluronic acid which give it viscous slippery texture similar to raw white.

synovial joint

-diarthrosis -glassy smooth articular cartilage covers opposing bone surfaces [prevents bone to bone contact] -joint cavity: space between the bones is a cavity lined by a synovial membrane -articular capsule: fibrous covering of the joint -joint cavity contains synovial fluid that reduces friction [secretes fluid that lubricates], serves as a shock absorber and nourished cartilage

rotation

Moving the bone around in a central axis

range of motion

The fullest extent of possible movement in a particular joint.

effort arm

The part of a lever from the fulcrum on which an effort force is applied.

resistance arm

The part of a lever that exerts the resistance force.

Cartilaginous Joint

a joint where the material between bones consists of cartilage that allows some movement between bones. Two types Synchondroses and symphyses

fibrous joint

a point at which adjacent bones are bound by collagen fibers that emerge from one bone, cross the space between them, and penetrate into the other. There are 3 type; Suture, gomphoses, an synesmoses

serrates suture

appears as wavy lines along the adjoining bones firmly interlock with each other by serrated margins

flexion

bending at the joint so that the angle between the bones is decreased