Joint & articulations

diarthroses

freely movable joints

synarthroses

immovable joints

flexion

is bending of a body part

hyperextension

is excess extension of a body part beyond the anatomical position

depression

is lowering a body part ex. lowering raised shoulders

dorsiflexion

is movement at ankle that brings the foot closer to the shin, in other words as if you are pointing the toes toward your head

plantar flexion

is movement at ankle that brings the foot farther from the shin, in other words as if you are standing on tip-toe

rotation

is moving a body part around an axis; aka twisting ex. twist head to side

retraction

is moving a body part backward ex. pulling shoulders back

protraction

is moving a body part forward ex. drawing shoulders forward

circumduction

is moving a body part in a circular path, as in a pitcher's wind up and pitch ex. moving your leg in a circle

abduction

is moving a part away from the midline of the body ex. raise arm out to the side

adduction

is moving a part toward the midline of the body ex. lowering raised arm to your side

elevation

is raising a body part ex. shrugging shoulders

extension

is straightening of a body part

eversion

is turning the foot laterally (out to the side) with the sole flattening

inversion

is turning the foot medially (in towards your side) with the sole raising

supination

is turning the palm of the hand up (superiorly or anteriorly)

pronation

is turning the palms of the hand down (inferiorly or posteriorly)

amphiarthroses

slightly movable joints

synovial joints

1. One of three general groups of joints 2. all free movement & are diarthroses (freely movable) 3. Ex. elbow, shoulder & hip

Gliding synovial joint (2)

1. The articulating surfaces of gliding joints are nearly flat or slightly curved. 2. Examples of gliding joints are joints within the wrists and ankles and joints between the articulating surfaces of the vertebrae.

hinge synovial joint (2)

1. The structure of a hinge joint is a convex surface of one bone fitting into the concave surface of another bone. concave / convex 2. An example of a hinge joint is the elbow joint.

pivot synovial joint (2)

1. The structure of a pivot joint is a cylindrical surface of one bone rotating within a ring formed of bone and a ligament. 2. An example of a pivot joint is the joint between the dens of the axis and ring of the atlas.

saddle synovial joint (2)

1. The structure of a saddle joint is a convex surface of one bone articulating with a concave surface of another bone. 2. An example of a saddle joint is the joint between the trapezium and the metacarpal of the thumb.

symphyses (2)

1. a type of cartilaginous joint 2. Ex. symphysis pubis & intervertebral joints

synchondroses (3)

1. a type of cartilaginous joint 2. many are temporary structures & disappear during growth 3. Ex. epiphyseal plate

Bursae

1. are fluid filled sacs associated with synovial joints. These structures are located between the skin and underlying bony prominences. 2. function to cushion and aid the movement of tendons that glide over bony parts or over other tendons.

General structure of synovial joints (1,2,3) 1/3

1. articular cartilage is a thin layer of hyaline cartilage that covers ends of bones 2. the joint capsule is a tubular structure that hold together the bones of a synovial joint. 3. The outer layer of the joint capsule consists of dense connective tissue.

6 types of synovial joints

1. ball-and-socket 2. condyloid 3. gliding 4. hinge 5. pivot 6. saddle

ball-and-socket synovial joint (3)

1. consists of a bone with a round head that articulates with a cup-shaped cavity of another bone. 2. A ball-and-socket joint allows a wider range of motion than any other type of joint. 3. Examples of ball-and-socket joints are the hip joint and shoulder joint.

condyloid synovial joint (2)

1. consists of a condyle fitting into a fossa or cavity of another bone. 2. An example of a condyloid joint is between the metacarpals and phalanges.

3 groups of joints

1. fibrous 2. cartilaginous 3. synovial

2 types of cartilaginous joints

1. synchondroses 2. symphyses

3 Types of synarthroses

1. syndesmosis 2. suture 3. gomphosis

gomphosis

1. type of synarthroses (immovable joint) 2. Ex. a joint formed between a tooth & bony socket in jaw

syndesmosis

1. type of synarthroses (immovable joint) 2. Ex. between tibia & fibula

suture

1. type of synarthroses (immovable joint) 2. Ex. sutures are only between flat bones of skull

General structure of synovial joints (4,5) 2/3

4. The inner layer of the joint capsule consists of a synovial membrane. This membrane produces synovial membrane. 5. Ligaments reinforce the joint capsule. a. Synovial fluid has a consistency of uncooked egg white and functions to moisten and lubricate the smooth cartilaginous surfaces within the joint.

General structure of synovial joints (6,7) 3/3

6. Menisci are discs of fibrocartilage. These function to cushion articulating surfaces. 7. Bursae are fluid filled sacs associated with synovial joints. These structures are located between the skin and underlying bony prominences. a. Bursae function to cushion and aid the movement of tendons that glide over bony parts or over other tendons.

Menisci

are discs of fibrocartilage. These function to cushion articulating surfaces. located btw articulating surfaces

joints (aka)

articulations