Ch 9 Articulations

immovable (largely restricted to the axial skeleton)

slightly movable (largely restricted to the axial skeleton)

freely movable (predominate in the limbs)

fibrous, cartilaginous, or synovial joints

immobile or minutely mobile (examples: joints of cranium and teeth)

• suture (short fibers) - immoble
• syndemosis (longer fibers) - slightly mobile
• gomphosis (periodontal ligament) - immoble

immovable joints formed by skull bones & connected by fibrous tissue

slightly movable but no true movement, formed by a ligament band of fibrous tissue. Amount of movement depends on length of the connecting fibers.

immobile and is a peg in socket as in the tooth and gum containing a small ligament

articulating bones are united by cartilage, no joint cavity, not highly moveable

• synchondrosis (hyaline cartilage) - immobile
• Symphysis (fibrocartilage) - slightly movable

hyaline cartilage that unites bones as in the ribs and sternum (immobile)

fibrocartilage that unites bones (growing together) as in the pubic symphysis and intervetrebral bones. Symphyses are slightly movable joints that provide strength with flexibility because fibrocartilage resists both tension and compression stresses & can act as a resilient shock absorber.

most moveable, has fluid filled cavity with synovial fluid, called diarthrosis, covered with articular cartilage

lines the ends of bones

synovial joints are contained by a fibrous capsule, a cavity filled with fluid called synovial fluid (makes synovial fluid)

viscous liquid that lubricates the joint

• ligaments - reinforce the joint
• nerves - protect it from over stretching

fibrous pouches made up of lined with synovial membranes. Bursa is a flattened fibrous sac and occurs where ligaments, muscles, skin, tendons, or bones overlie each other and rub together

have same compnents as bursa, but are longer and wider, more like a sheath.

highly lubricated to facilitate motion, routinely experience compression, and the fluid moves to accomodate the pressure

ligaments strengthen the joint and prevent it from moving incorrectly, not as flexible and capable of reshaping

• flat articulating surfaces that allow for short gliding movements as in the wrist bones (intercarpals), ankle bones (intertarsals), and vertebral bones, no rotation around an axis (non-axial)
• - only occurs along the plane of the joint surface
• - short gliding movements

• movement is along one plane (uniaxial). examples are elbow and knee (
• - allow movement around one axis only
• -flexion and extension

• rounded end of one bone fits into the other, also uniaxial. examples are the radius & ulna and atlas & dens
• - rounded end of one bone fitrs into a ring that is formed by another bone plus an encircling ligament
• - rotation

• knucle like, oval like shape of one bone fits into an oval bowl like shape of the other. It does not rotate around its axis but can move side to side and back and forth, it is biaxial. (examples: knucle or metacarpophalangeal joint spreadning fingers apart/together or flex/extend them)
• - cannot rotate around its long axis
• - flexion & extension; adduction and abduction

• two ends fit into one another as a person sitting in a saddle does. They are biaxial such as the thumb joint (first carpometacarpal joint)
• - each articular surface has both convex and concave areas
• - adduction/abduction, flexion/extension

spherical end fits into round socket, allows movement in multiple planes of axis (triaxial) such as the hip and shoulder

- flexion/extension, adduction/abduction, rotation

TMJ - a synovial joint that has an articular capsule, hinge like movement, & anterior movement. It is so shallow and can be easily dislocated

less stable, but more movable. glenoid fossa is lined with fibrocartilage callled genoid labrum, ligaments supprt limb weight, and muscle tendons contribute to stability. This joint has a rotator cuff formed by tendons & also has bursa and tendon sheaths

stable hinge joint with the ligaments stabilizing & preventing lateral/medial movements

largest & most complex including the femur, tibia, && patella

guide the condyles

patellar ligament, medial & lateral ligament

support the joint capsule

stretch or torn ligaments

bones are forced out of alignment & must be reduced (returned to original location).

a partial dislocation

when it is subjected to high compression & tension. example: meniscus tearing. Does not heal itself thus broken fragments are removed by arthroscipic surgery

swelling of the bursa or tendon sheaths

inflammation or degeneration of the joints

• osteoarthiritis - joints wearing out where use of joint causes enzyme that breakdown the cartilage to breakdown.
• rheumatoid arthritis - immune system attacks the cartilage causing inflammation & muscle weakness (affects women more than men)
• gouty arthritis - uric acid accumulates in joints causing inflammation at the joints (affects men more than women)
• lyme disease - bacteria transmitted by tick bites causes joint inflammation & many other symptoms (difficult to diagnose and treat)

a combination of flexion, extension, abduction, and adduction (making a circle)

Rotation is a movement of bone along its own axis with only 3 areas that can do this: atlas and axis, shoulder joint, and hip joint.

• supination - lateral radial rotation to turn palm anteriorly (palm up)
• pronation - medial radial rotation to turn palm posteriorly (palm down)