articulations Flashcards
Articulations
joints
Stability and ROM are
inversely proportional
3 classifications of joints
Synarthrosis, amphiartesis, and diarthrosis
Synarthrosis
no cavity, capsule, membrane, or fluid
-most stable joint
-bones connected by dense fibrous ligaments
-Sutures and Syndesmoses
Sutures
connected by fibers that are continuous with the periosteum
-skull is only place that has these
Syndesmosis
connected by fibrous tissue
-coracoacromial joint (scapula)
-Tibiofibular joint (high ankle sprain)
Amphiarthrosis
none
-permit more motion than syndesmoses
-synchondrosis
-symphyses
Synchondroses
joints held by hyaline cartilage
-sternocostal joints (ribs and sternum)
-Epiphyseal plates (movement in long bones)
symphyses
bones held by cartilage and fibrocartilage (shock absorption)
-intervertebral joints
-pubic symphysis
Diarthrosis
-freely moveable joints
-articular cavity, fluid, ligaments, membrane, covered with hyaline cartilage
-richly supplied with sensory nerves
Uniaxial joints
Gliding, pivot, and hinge
gliding joints
flat planes
-short gliding movements
-intertarsal and intercarpal joints
-nonaxial
hinge joints
cylindrical end of one bone fits into trough on another
-elbow, ankle, and joints between fingers and toes
-uniaxial-sagittal
Pivot joints
-rotating bone only turns around its long axis
-transverse plane
-proximal radioulnar joint
-joint in spine
Biaxial joints
condyloid and saddle
condyloid joints
-circumduction
(frontal) side to side-abduction/adduction
(sagittal) back and forth- flexion/extension
-convex surface with concave surface
-metacarpal phalangeal joints
-wrist joints
Saddle Joints
-more range of motion (looks like saddle)
-circumduction
-first carpometacarpal joint
Triaxial joints
Ball and socket and Bicondyloid
Ball and Socket
Spherical head of one bone fits into round socket of another
-multiaxial
-shoulder and hip
Bicondyloid
two convex and two concave surfaces
-8 deg of rotation
-valgus+ knocked knee; varus= bow legs
Types of cartilage
hyaline, elastic, and fibrocartilage
Hyaline Cartilage
most abundant type of cartilage
-provides support via flexibility and resilience
elastic cartilage
greatest flexibility and can tolerate repeated bending
-outer ear, epiglottis, eustachian tube
fibrocartilage
provides shock absorption
-very strong in resisting tension and compression
-menisci of knee, intervertebral discs, TMJ, and pubic symphysis
Articular Cartilage
comprised of hyaline cart.
-chondrocytes embedded in a matrix of collagen and other proteins
-maintain and restore cartilage with wear
function of articular cartilage
distributes load over a wide area to reduce stress
-allows movement at joints with minimal friction
-friction is less than half of ice
-acts like a sponge to soak up and re-disperse synovial fluid
synovial membrane
manufactures synovial fluid
-located in the lining of the joint
