Ch. 8 Joints

A&P 1- Joints, Lonestar College objectives, McDowell

Joint

site where 2 or more bones articulate

synarthroses

immovable

amphiarthroses

slightly moveable

Diarthroses

freely moving

Fibrous joints

connected by fibrous connective tissue

no cavity present, generally synarthroses

examples of fibrous joints

Sutures, short ligaments (syndesmoses), gomphoses (peg in socket - ex. ligament holds tooth in socket)

cartilaginous joints

connected by cartilage

no cavity present.

usually synarthroses to amphiarthroses.

2 types

what are the 2 types of cartilaginous joints?

1. synchondrosis

2. symphysis

synchondroses

bones are connected by hyaline cartilage

symphyses

bones are united my fibrocartilage

synovial joints

fluid filled cavity is present

most common

generally diarthroses,

Origin

attachment to the bone that does not move when muscle contracts

Insertion

attachment to the bone that moves during contraction

Types of movements

Gliding, rotation, angular

Gliding

one flat surface slips smoothly across another

Rotation

moving around axis

angular

causes increase/decrease in angle between 2 bones

Uniaxial

movement in 1 plane

Biaxial

movement in 2 planes

multiaxial

movement in multiple planes

plane joint (synovial type)

flat articulating surfaces

gliding

hinge joint (synovial type)

allows uniaxial angular motions

flexion and extension

pivot joint (synovial type)

allows rotation

condyloid joint (synovial type)

allows all angular motions

saddle joint (synovial type)

Complimentary concave
and convex areas on each
bone
Allows all angular motions

Ball and socket (synovial type)

spherical head of bone fits in deep cavity of other

allows all motions

sprain

ligament is stretched or torn

ex. ankle, knee, lumbar

dislocation

bones are out of normal position

ex. shoulder, fingers

Bursa

acts as a cushion to prevent friction between

bones and tendons

bone and muscle

skin and bones

arthritis

very common

disease that damages the joints

osteoarthritis

age related

cartilage wears away exposing bone

bone spurs develop

more common in women

rheumatoid arthritis

auto-immune disease

3x more likely in women

inflammatory

scars in joint cavity ossify and bones fuse

Gouty arthritis

metabolic disorder

more common in men

uric acid is deposited in cavity

starts with inflammation of big toe

could be genetic

several effective drug therapies