Introduction pt1 Flashcards
sagittal plane
is vertical and divides the body into right and left sides
what are the joint motions w/in the sagittal plane
flexion and extension
flexion
2 segments of the body approaching each other
extension
2 segments of the body moving away from each other
hyperextension
beyond the normal anatomical position
pure sagittal plane
divides the body directly down the middle
equal right and left sides
parasagittal plane
sagittal plane moves off center
right and left sides are not equal
frontal plane
also named coronal
is vertical and divides the body into front and back parts
what joint motions are in the coronal plane
ABD and ADD
ABD
position or motion away from midline
ADD
position or motion towards midline
transverse
also called horizontal
is horizontal and divides the body into upper and lower parts
joint motions of the horizontal plane
IR and ER
IR
rotation oriented towards the anterior surface of the body
ER
rotation oriented towards the posterior surface of the body
where are the three axes of motion located
intersection of the 3 planes of space
how is each axis placed
perpendicular to the plane in which the motion occurs
frontal axis
x axis
the axis passes horizontally from side to side
perpendicular to the sagittal plane
motions that occur around the x axis
flexion and extension
vertical axis
also called y-axis
axis passes perpendicular to the ground and to the transverse plane
motions that occur around the y-axis
IR and ER
sagittal axis
z axis
pass horizontally from front to back and is perpendicular to the frontal plane
motions that occur around the z-axis
ABD and ADD
2 broad categories of joint design
synarthrosis and diarthrosis
what are the 2 joint design categories based on
the type of materials and the methods used to unite the bony components
synarthrosis joints
no mobile, not synovial joints
material used to connect the surfaces is interosseous connective tissue
fibrous or cartilaginous
firmly joins 2 bones
built for stability
2 types of synarthrosis joints
fibrous joints
cartilaginous joints
fibrous joints
fibrous tissue directly unites bone to bone
3 types of fibrous joints
suture joint
gomphosis
syndesmosis
suture joint
bones united by thin layer of dense fibrous tissue
found only in the skull
allows very little movement
gomphosis joint
bony components are adapted to each other like a peg in a hole
b/w the tooth and the mandible or maxilla
syndesmosis joint
bony components are joined directly by a ligament, cord, or aponeurotic membrane
ex: tibia and fibula w/ a interosseous membrane
cartilaginous joints
material used is either fibrocartilage or hyaline growth cartilage
2 types of cartilaginous joints
symphysis joint
synchondrosis joint
symphysis joint
components are directly joined by fibrocartilage in the form of disks or plates
ex: symphysis pubis
synchondrosis joint
components are connected by hyaline growth cartilage
it forms a bond b/w ossifying centers
ex: 1st sternocostal joint
diarthroses joint
synovial joints
the bony components are free to move in relation to each other b/c no cartilaginous tissue directly connects adjacent bony surfaces
indirectly connects by means of a joint capsule that encloses the joint
accessory structures of diarthrosis joints
discs
plates
menisci
labrums
fat pads
ligaments and tendons
roles of ligaments and tendons in diarthrosis joints
keep joint surfaces together
may assist in guiding motion
ligaments –> bone to bone
tendons –> bone to muscle
separation of synovial joints
limited by passive tension in static stabilizers of the joint
active tension of muscles also limits separation of joint surfaces (dynamic stabilizers)
what are static stabilizers of the joint
joint capsule
ligaments
tendons
what are dynamic stabilizers of the joint
muscles
what are the common features of every diarthrodial joint
joint capsule
joint cavity
synovial membrane lining
hyaline cartilage covering the bony surfaces
synovial fluid
joint capsule
has 2 layers
outer layer and inner layer
outer layer of the joint capsule
stratum fibrosum
dense fibrous tissue
poorly vascularized
richly innervated by joint receptors
what can the joint receptors detect
rate and direction of movement
compression
tension
vibration
pain
inner layer of the joint capsule
stratum synovium
highly vascularized
poorly innervated by joint receptors
specialized cells that make hyaluronate
what is hyaluronate
component of synovial fluid
joint cavity
is enclosed by the joint capsule
synovial membrane lining
lines the inner surface of the capsule
hyaline cartilage covering the boney surface
is a specialized cartilage
allows for friction free motion
can’t heal –> will lead to osteoarthritis is damaged
synovial fluid
lubricates the joint and reduces friction b/w the bony components
provides nourishment of the articular (hyaline) cartilage
3 subclassifications of diarthrodial joints
complexity of organization
number and distribution of axes (degrees of freedom)
geometric form
complexity of organization
simple
compound
complex
simple
there are 2 articular surfaces
ex: hip joint, head of the femur with the acetabulum
compound
more than 2 articular surfaces
ex: elbow joint, humerus articulate with the radius and the ulna
complex
the presence of a disc b/w the surfaces
ex: knee joint, femur articulates w/ menisci, tibia and fibula
degrees of freedom
non-axial
uni-axial
bi-axial
tri-axial
non-axial joint
gliding joint (0 degrees of freedom)
no pure motions or axes
ex: carpal bones
uni-axial
one degree of freedom
motion occurs in only 1 plane around only 1 axis
hinge and pivot joints
ex: interphalangeal joints and elbow joint
bi-axial joint
two degrees of freedom
has 2 axes and moves in 2 planes
ex: MCP joints of the hand and radiocarpal joints of the wrist
usually condyloid (ellipsoid) and saddle joints
tri-axial
three degrees of freedom
movement takes place about 3 axes and planes
ex: hip joint
ball and socket joint
geometric form classification
plane joint
hinge joint
pivot joint
condyloid joint
saddle joint
ball and socket joint
plane joint
a gliding or non-axial joint
there is gliding b/w 2 or more bones
hinge joint
ginglymus joint
uni-axial
joint resembles a door hinge
permits motion around a single axis
example of a hinge joint
IP joints
elbow joint
knee joint
pivot joint
trochoid
uni-axial
one component is shaped like a ring while the other is shaped so that it can rotate within the ring
example of a pivot joint
median atlanto-axial joint
condyloid joint
ellipsoid
bi-axial
surfaces are shaped so that the concave surface of 1 bony component is allowed to slide over the convex surface of another component in 2 direction
example of ellipsoid joint
MCP joint
saddle joint
bi axial
each join surface is both convex in one plane and concave in the other and these surfaces are fitted together like a rider on a saddle
example of a saddle joint
CMC joint of the thumb
ball and socket joint
tri-axial
joints in which the bony components are free to move in 3 planes around 3 axes
formed by a ball like convex surface being fitted into a concave socket
example of a ball and socket joint
hip joint
