1. Chapter 9 Pages 275-80, 284-294 Arthrology= study of joints & associated disorders Kinesiology= study of musculoskeletal movement Biomechanics= broader ÷ dealing w/ motion/mechanics of body Articulation (joint)= pt where 2 bones meet; can be movable, moderately, or immovable 3 classifications based on movement: diarthrosis (freely, elbow) amphiarthrosis (slightly, intervertebral jnt) synarthrosis (little/no, suture) Joints named after bones associated w/ it Joints classified according to way bones attach to each other 4 types of joints- fibrous, cartilaginous, bony, & synovial

2. 4 types of joints Bony joint (synostosis)- 2 separate bones fuse (ossify) to form ‘single’ bone Frontal bone, mandible; epiphses & diaphyses ossify as adults Some cranial sutures of elderly may completely ossify, transforming from a synarthrosis to a synostosis Rib 1 fuses to sternum with age Fibrous joint (synarthrosis)= collagen fibers of 1 bone extend into matrix of another bone 3 types= sutures, gomphoses (teeth…periodontal ligament), & syndesmoses Sutures & gomphoses have short fibers= little movement Sutures ONLY present in skull 3 types include serrate, lap, & plane sutures

3. Fibrous joints (cont.) Fibrous joint (cont.)- Gomophoses allow for slight movement of teeth, giving us sense of how hard we are biting down, food in teeth, etc. Syndesmoses have longer fibers= movable joints Less moveable joint….distal ends of tibia/fibula More moveable joint.…radius/ulna & tibia/fibula by interosseous membrane Interosseous membrane allows for supination/pronation

4. Joint Types (cont.) Cartilaginous joint (amphiarthrosis)- 2 bones bound together by either hyaline or fibrocartilage Synchondroses= hyaline cartilage binds bones together Epiphysis & diaphysis fuse (epiphyseal plate); costal cartilage Symphyses= fibrocartilage joins 2 bones Pubic bones join by a interpubic disc to form pubic symphysis 23 intervertebral discs between vertebrae allow for flexibility yet permits only slight movement between each adjacent bone Synovial joint- most common jnt; 2 bones separated by a space filled w/ synovial fluid Elbow, knee, jaw, hip…all freely movable Health & mobility of synovial joints important throughout life Loss of flexibility (range of motion) w/ age, rheumatoid arthritis, etc. Exercise & articular cartilage (insight 9.1)

5. Cartilaginous & synovial joints

6. Synovial Joints General structure of a synovial joint- Cavity w/ fluid that nourishes/removes wastes of articulating cartilage Bones covered w/ articular cartilage Fibrous jnt capsule encloses cavity & outer fibrous capsule is continuous w/ periosteum Synovial membrane of mostly areolar tissue secretes fluid Meniscus= pad btw bones to absorb shock/pressure, guides bones across each other, distributes force across entire joint Tendons, ligaments, & bursae common in synovial joints remember tendons/ligaments are made of dense regular connective tissue (tough collagen fibers) Bursae= fibrous sac filled w/ synovial fluid found btw muscles or where tendons pass over bone also forms tendon sheaths…bursae wrapped around tendons of hand & foot

7. Synovial joints (cont.) 6 types of synovial joints- 4 common joints are…. Ball-&-socket joint= shoulder, hip Only multiaxial joints (multidirectional movement) Glenoid cavity + head of humerus; acetabulum + head of femur) Gliding joint= carpal & tarsal bones, vertebrae, sternoclavicular joints Limited monaxial movement (amphiarthroses) ‘Flat or slightly curved’ articulating surfaces slide over each other Combine movement of several bones produces significant ROM Hinge joint= elbow, knee, interphalangeal joint Monaxial joints (1-directional plane) Convex surface fits into concave depression of other bone Trochlea + trochlear notch; condyles of femur + tibial condyles Pivot joint= atlantoaxial jnt, proximal radioulnar jnt Monaxial joints where 1 bone ‘spins’ on its longitudinal axis

8. Movements of synovial joints ** When in anatomical position, joint is in ‘zero position’ Flexion/extension Hyperextension= greater than 180 o Abduction/adduction (away/towards midline) Elevation/depression (vertical plane; clavicle) Protraction/retraction (horizontal plane; jaw) Circumduction (1 pt stays stationary, while distal end makes a circle) Lateral & medial rotation (femur, humerus, waist) Supination/pronation (hands & feet only) Opposition/reposition (thumbs only, thumb to finger tips) Dorsiflexion/plantar flexion (feet only…toes up, toes down)