first half; i hate it here

articulations

joints; where two bones meet

2 fundamental functions of joints

secure bone together and allow movement

joints are classified by _________ & ________

functional classification & structural classification

the structural classification is based on

material binding bone & presence / absence of a joint cavity

functional classification is based on ______ & includes three levels (synarthroses, amphiarthroses, diarthroses)

degree of movement

synarthroses

immovable joints (sutures in skull)

Amphiarthrosis

slightly movable joint

diarthroses

freely movable joints

fibrous joints

bones united by fibers; no joint cavity

Fibrous Joints: Sutures

found only in skull

fibrous joints: syndesmoses

united by a ligament

fibrous joints: gomphoses

tooth-in-jaw (peg-in-socked) periodontal ligament

cartilagenous joints

bones united by cartilage, no joint cavity

cartilagenous Joints: synchondroses

bones are united by a bar/plate of hyaline cartilage (almost all are immovable / synthartic)

Cartilagenous joints: symphyses

bones are united by fibrocartilage (strong, slightly moveable)

synovial joints

synovial membranes and synovial fluid; HAVE a joint cavity; all are freely moveable

articular cartilage

hyaline cartilage covering ends of bone; prevents crushing of bone ends

Joint (Articular) Cavity

only in synovial joints; potential space (can expand if fluid accumulates) happens during inflammation

articular capsule

2 layers thick; fibrous layer & synovial membrane

articular capsule: fibrous layer

dense irregular connective tissue; continous with periosteum of articulating bone; strengthens joint so bones are not pulled apart

articular capsule: synovial membrane

loose connective tissue; covers all internal joint surfaces that are not hyaline cartilage; makes synovial fluid

synovial fluid in synovial joints

small amount occupies all free space in joint capsule, eggwhite consistency, provides weight-bearing film, removes microbes and debris

reinforcing ligaments of synovial joints

capsular, extracapsular, intracapsular

reinforcing ligaments: capsular

thickened part of fibrous layer

reinforcing ligaments: extracapsular

outside the capsule

reinforcing ligaments: intracapsular

deep to capsule; covered by synovial membrane

nerves and blood vessels of synovial joints

rich supply of sensory nerve fibers, some detect pain while most monitor position and stretch, produce the blood filtrate

fatty pads

Provide cushioning between fibrous layer and synovial membrane; HIPS & KNEE JOINTS

articular discs (menisci)

discs / wedges of fibrocartilage seperating articular surfaces; stabilizes joint & minimizes wear and tear at the joint surface

bursae

flattened fibrous sacs lined with synovial membrane and containing a thin film of synovial fluid; reduces friction and found where ligaments, muscles, skin, tendons, or bone rub together

tendon sheath

elongated bursae that wrap completely around a tendon subjected to friction

3 factors that influence the stability of synovial joints

1.) shape of synovial joints 2.) ligament number and location 3.) muscle tone