Post on 25-Dec-2015
Joints of the bodyClassification and mobility
Fibrous- no joint cavity, joined by fibrous tissue, mobility depends on the length of the tissue, most are immovable
Cartilaginous- lack a cavity and bones are joined by cartilage which allows for compression and resilience but not mobility
Synovial – fluid containing joint cavity, freedom of movement, majority of joints
Classification: 3 classes
Suture◦ Bones connected by short fibers◦ Immovable◦ Found in the skull
Syndesmosis◦ Bones connected by longer fibers, ligaments◦ Ex. The connection of the tibia and fibia, immovable◦ Ex. The connection of the radius and ulna slightly
movable allowing for rotation Gomphoses
◦ Periodontal ligament◦ Connects the tooth to the bony alveolar socket◦ Immovable as if “hammered in”
Fibrous
Synchondroses◦ A plate of hyaline cartilage unites the two bones◦ Joint between the growth plate of long bones and
the mature bone, seen in children◦ Joint between the first rib and the manubrium of
the sternum Symphyses
◦ The hyaline cartilage at the end of the bone is connected to a pad of fibrocartilage which is more compressible and resilient, allowing the joint to absorb shock and be flexible
◦ Intervertebral joints and the pubic symphysis of the pelvic bone
Cartilaginous
Same general structure Types: plane, hinge, pivot, condyloid,
saddle, ball and socket Freely movable, depends on design
Bursae and Tendon Sheaths◦ Assist with flexibility of the joint◦ Bursae are fluid filled sacs that line the area
where ligaments, muscles, skin, tendons, and bones rub together.
Synovial joints
General structure
a. Plane b. Hinge c. Pivot d. Condyloid e. Saddle f. Ball and
socket
Types of Synovial joints
Every skeletal muscle is attached in no less than two points.◦ Muscle origin is attached to an immovable bone◦ Muscle insertion is attached to a movable bone
Movement occurs when muscles contract across a joint
Described by the direction in relation to the axis: nonaxial, uniaxial, biaxial, multiaxial
Movement
Gliding- simple back-and-forth, and side to side◦ Include the tarsal and carpal◦ Include the vertebra◦ And is incorporated into other movements
Angular- increase or decrease the angle between two bones◦ Movement of limb by flexion, extension,
abduction, adduction, circumduction Rotation- turning a bone on its axis
◦ Include hip and shoulder◦ Include the 1st two cervical vertebrae
Three types of movement
Common Joint Injuries Sprain- ligaments stretched or torn Cartilage injuries- can not heal must be
removed or joints can get locked up Dislocations- bones are forced out of alignment
Inflammatory and Degenerative ConditionsBursistis- inflammation of the bursaTendonitis- inflamation of tendon sheathsOsteoarthritis and Rheumatoid ArthritisGout Arthritis- high uric acid levels accumulate
and inflame the joints