joint mechanics Flashcards
frontal plane axis
anteroposterior
sagittal plane axis
medial-lateral
horizontal/transverse plane axis
longitudinal
kinematics
description of motion without regard to the forces producing the motion
kinetics
study of forces producing motion and or maintaining equilibrium
osteokinematics
study of the movement of a bone without regard for the motion occurring at the joint surface or the forces producing the movement
how do you measure osteokinematics
goniometers and inclinometers
uniaxial
1 degree of freedom
ex. hinge joints: the humeroulnar joint or proximal radioulnar joint that pivots
biaxial
2 degrees of freedom
CONCAVE AND CONVEX
saddle and sellar
sellar joints
joint surface is concave in one direction and convex in the other direction
triaxial
3 degrees of freedom
planar and ball and socket joints
circumduction
combines all degrees of freedom
minimal of 2 degrees of freedom
synarthrodial
bony components connected by connective tissue
designed for stability and minimal movement
suture
united by collagenous sutural ligament/membrane
gomphosis
peg in a hole (ex. mandible)
syndesmosis
interosseous ligament, fibrous cord or aponeurotic membrane
cartilaginous
bone-cartilage bone interface
symphysis
directly joined by fibrocartilage
synchondrosis
hyaline cartilage forms a body between the two bones
ex. rib connection to sternum
diarthrodial (synovial)
bones are indirectly connected by means of a joint capsule
ruffini receptor
stretch receptor
pacini receptor
compression, changes in hydrostatic PRESSURE and joint MOVEMENT
golgi receptor
pressure receptor and extremes of motion
unmyelinated free nerve endings are sensitive to
noxious/non-noxious mechanical or biomechanical stress
unmyelinated free nerve endings location
around blood vessels in synovial layer of capsule and fat pads
ligaments, tendons and periosteum
golgi location
intima of synovium, ligaments and tendons
pacini location
throughout the joint capsule, fat pads
Ruffini location
fibrous joint capsule, periosteum, ligaments, tendons (flexion side)
compound joint
has one or more pair of articular surfaces within the capsule
complex joint
has an intra-articular disc b/w joint surfaces
sub-intima
loose network
attaches to margins of articular cartilage, periosteum and fibrous capsule
intima
synoviocytes are 1-3 layers)
lines the joint space and interacts with it
responsible for exchange with the synovial fluid, removal of debris from joint cavity and structural repair of synovium
what does the intima synthesize
hyaluronic acid to keep the friction low
what interacts directly with the intima
synovial fluid
function of synovial fluid
keeps joint surfaces lubricated, has viscosity from hyaluronic acid and has low friction due to lubricin
function of discs, plates, menisci, labrum
increase joint congruency, absorb compressive forces, facilitate motion, deepen cavity
bursae
lined with synovial membrane, filled with a thin fluid
flat, dense, irregular CT sac
either subcutaneous, subtendinosis, and submuscularis
open kinetic chain
proximal segment is fixed and distal segment can move
closed kinetic chain
distal segment is fixed and stabilized and the proximal segment is moving
generally weight bearing
kinetic chain definition
combo of several joints uniting successive segments (series of rigid links)
saddle joints are ___
sellar; have both convex and concave on the same articular surface
ovoid joints
joint surfaces are curved in the same direction as the articular partner
arthrokinematics
the study of the movement of one articular surface on another without regard to the movement of the bone or the forces producing that movement
rolling
each subsequent point on one surface contacts a new point on the other surface
SAME DIRECTION AS THE MOVEMENT
gliding/sliding
same point on one surface contacts new point on the other surface, maintains optimal joint contact, direction depends on the surfaces and type of joint
normal joint motion
combination of rolling, gliding and spinning
convex on concave
rolling and gliding are opposite
concave on convex
gliding and rolling are in the same direction
treatment plane
line parallel to the concave articular surface
distraction joint glide
perpendicular to the treatment plane
traction joint glide
along long axis of the bone- parallel to treatment plane
close packed position
maximum tautness of ligaments
maximum surface congruity/contact
min joint volume
maximum stability to allow for least distraction
loose packed position or open packed
any position other than the close packed position
capsule and ligaments on slack
max joint volume
joint surfaces may distract several mm
allows for necessary roll, glide and spin
what position does a joint go into with inflammation
open packed or loose packed
what position do we do joint mobilizations
loose packed/open packed
common convex bones
capitulum, femoral head, femoral condyles, talus, olecranon, humeral epicondyles, humeral head
common concave bones
glenoid fossa, acetabulum, radial head, tibial plateaus, distal tibia and fibula, olecranon fossa,
synarthrosis
designed for stability
diarthrosis designed for ____
mobility (through synovial capsule)
primary cartilaginous joint
synchondrosis
secondary cartilaginous joint
symphysis
outer fibrous capsule function
enclose the joint and provide stability
describe the dense irregular CT in synovial jt capsule
70% water highly innervated poorly vascularized variable thickness 90% collagen/elastin in dry weight
intima is responsible for
synthesis of hyaluronic acid, remove debris from the capsule and structurally repair synovium
sternoclavicular retraction
concave clavicle on convex sternum
posterior roll, posterior glide
sternoclavicular elevation
convex clavicle on concave sternum
Superior roll, inferior glide
treatment plane
lies in the concave joint surface, parallel to the joint surface
