articulations Flashcards
mobility vs stability
more mobility means less stability
arthrology
study of joints
joints from most mobile to most stable
glenohumeral (shoulder)
hip
elbow
intervertebral
suture
joints are classified by
structure (material binding the bones) and function (range of motion)
functional classifications of joints
synarthrotic, amphiarthrotic, diarthrotic
synarthrotic
immovable
ex: suture
amphiarthrotic
slightly movable
ex: intervertebral
diarthrotic
freely movable
ex: shoulder, limbs
ehlers-danlos syndrome
group of inherited disorders that affect CT, primarily skin, joints, and blood vessels
overly flexible joint, hypermobile, stretchy fragile skin
structural classifications of joints
fibrous, cartilaginous, synovial
fibrous joints
joined by fibrous tissue (CT)
most are synarthrotic, some amphi
3 types of fibrous joints
sutures, syndesmoses, gomphoses
synostoses
fibrous tissue ossifies
ex: skull bones fuse
syndesmoses
bones connected by ligament, cord, or band of fibrous tissue
amphiarthrotic
have interosseous ligament
interosseous ligament
articulating bones held side by side by a ligamentous sheet, provides pivot point for bones to rotate against each other
gomphoses
peg in socket joint
ex: tooth in bony alveolar socket
cartilaginous joints
bones united by cartilage, no joint cavity
2 types of cartilaginous joints
synchondroses, symphyses
synchondroses
bar or plate of hyaline cartilage
symphyses
articular cartilage fused to a pad or plate of fibrocartilage, designed for strength and flexibility
amphiarthrotic
shock absorption, resist compression and tension
synovial joints
separated by fluid containing cavity
most abundant
widest ROM (diarthrotic)
parts of synovial joint
articular capsule, synovial cavity, synovial fluid, articular cartilage, reinforcing ligaments
articular capsule
richly innervated, maintain joint position, maintain muscle tone
1. fibrous layer on outside, made of dense irregular CT
2. synovial membrane on inside, where synovial fluid originates
synovial cavity
contains synovial fluid, separates bones
synovial fluid
blood filtrate, “weeping lubrication”
weeping lubrication
articular cartilage takes up synovial fluid and releases it when compresses, maintains lubrication
articular cartilage
thin layer of hyaline cartilage that lacks perichondrium,
cushions
reinforcing ligaments
strengthens and reinforces joint
intrinsic- within joint
extrinsic- outside joint/articular cartilage
bursae
flattened fibrous sacs with synovial membrane and thin layer of synovial fluid
reduces friction
tendon sheath
elongated bursa that wrap around tendon to reduce friction
fat pads
adipose tissue distributed along periphery of synovial joint, protects and fills in open space
tendons
dense regular CT that attaches muscle to bone
skeletal muscle attachment points
origin and insertion
origin
muscle attached to immovable bone
insertion
muscle attached to movable bone
movement occurs when … moves toward …
insertion, origin
ROM of muscles
uniaxial, biaxial, multiaxial
uniaxial movement
movement in one plane
biaxial movement
movement in 2 planes
multiaxial movement
movement in multiple planes
types of synovial joints (6)
hinge, planar/gliding, saddle, condylar, ball and socket, pivot
hinge joint
uniaxial
ex: elbow
planar/gliding joint
uniaxial
simplest, least movable
ex: carpals
saddle joint
biaxial
ex: thumb carpometacarpal
condylar joint
biaxial
ex: metacarpal (knuckle)
pivot joint
uniaxial
rotation of one bone along longitudinal axis
ex: axis vertebra
ball and socket joint
multiaxial
ex: hip
gliding movement
simplest, bone gliding over another surface
angular movements
changes angle between bones
flexion, extension, hyperextension, lateral flexion, abduction, adduction, circumduction
flexion
decrease angle
ex: bicep curl up
extension
increase angle
ex: bicep curl down
hyperextension
beyond 180°
ex: extend hand up, bend knee backwards
lateral flexion
trunk moves distal laterally in coronal plane
abduction
move limb medially (away from midline)
adduction
move limb toward midline
circumduction
like a cone, point is stationary white the distal end moves in a circle
rotational movements
rotation, supination, pronation
rotation
turning along longitudinal axis, toward or away from midline
supination
radius and ulna are parallel
pronation
radius and ulna crossed
elevation/depression
up and down
inversion/eversion
sole of foot moves medially (inversion) or laterally (eversion)
dorsiflexion/plantar flexion
foot moves up at the ankle (dorsiflexion) or down at the ankle (plantar flexion)
protraction/retraction
moves anteriorly (protraction) or posteriorly (retraction)
opposition/reposition
touching fingers to thumb (opposition) or taking them away (reposition)
temporomandibular joint
small complex, only movable articulation between skull bones
hinge, pivot, and gliding
articular capsule promotes an extensive rom
articular disc separates synovial cavity into 2
structurally bicondylar but classified as a modified hinge
3 ligaments of TMJ
temporomandibular/lateral ligament, stylomandibular ligament, sphenomandibular ligament
knee joint
largest most complex diarthrosis
bursae: suprapatellar bursa, prepatellar bursa, infrapatellar bursa
“joints”: knee, tibiofemoral, patellofemoral
sprain
stretched or torn ligament
cartilage injury
tearing knee menisci, growth plate fissure, overuse damage to articular cartilage,
slow or no repair
luxation
bones forced out of alignment
bursitis
inflammation of bursa due to excessive stress, a blow or friction
tendonitis
inflammation of tendon sheath
osteoarthritis
degenerative joint disease that involves deterioration if cartilage at ends of bones, articular surface becomes rough and pieces break off into synovial cavity
weakening, deforming or joint, stiffness and pain
rheumatoid arthritis
women 3x men, 40-50, chronic inflammatory autoimmune disease
tenderness snd stiffness due to inflammation if synovial membrane
pannus forms (thickened synovial membrane, scar tissue)
RA vs OA
rheumatoid due to inflammation in lining of joint, osteo is a wear process, cartilage wears down
