Joints Flashcards
What is the weakest parts of the skeleton?
Joints (articulations)
Articulation/Joints
site where two or more bones meet
Functions of a Joint
Give skeleton mobility
Hold the skeleton together
What joints classified by?
Structure
Function
Structural Classification of Joints
focuses on the material binding bones together and whether or not a joint cavity is present
3 structural classifications of joints
Fibrous
Cartilaginous
Synovial
Fibrous Structural Class of Jts
united by collagen fibers
cartilaginous structure joints
united by cartilage
Synovial joints
covered with cartilage; enclosed within capsule
Functional Classification of Joints
is based on amount of movement by the joint
Synarthroses
Amphiarthroses
Diarthroses
Synarthroses
immovable (cartilaginous) function
Amphiarthroses
slightly movable
Diarthroses
freely movable (synovial) function
Bones are joined by?
fibrous tissues
In fibrous structural joints, there is no?
Joint cavity
Most fibrous structural joints are?
immovable
There are three types of fibrous structural its, what are they?
sutures
syndesmoses
gomphoses
Sutures occur between what?
bones of the skull
Sutures are comprised of?
interlocking junctions completely filled with connective tissue fibers
sutures bind
tightly together, but allow for growth during youth
syndesmoses
bones are connected by a fibrous tissue ligament
syndesmoses movement?
varies from immovable to slightly
Example of syndesmoses
connection between the tibia&fibula and ulna&radius
Gomphoses socket type
Peg-in-socket fibrous jt between a tooth and its alveolar socket
Gomphoses fibrous connection
is the periodontal ligament
Cartilaginous joints are
articulating bones united by cartilage
Cartilaginous joints lack what?
a joint cavity
Two types of cartilaginous joints?
synchondroses
symphyses
Synchondroses
a bar or plate of hyaline cartilage unites the bones
All synchondroses are?
synarthrotic (lil to no movement)
Epiphyseal plates of children is an example of?
synchondroses
Jonts between the costal cartilage of the first rib and sternum is example of?
synchondroses
Symphyses
Hyaline cartilage covers the articulating surface of the bone and is used to an intervening pad of fibrocartilage
intervertabral joints and pubic symphysis of pelvis is an example of ?
symphyses
Synovial Joints
Those joints in which the articulating bones are separated by a fluid-containing joint cavity
Synovial joints function
all are freely movable
diarthroses
all limb joints, and most joints of the body are examples of?
synovial joints
5 parts of synovial joints
1) Articular cartilage (hyaline)
2) Joint (synovial) cavity
3) Articular capsule
4) Synovial fluid
5) Reinforcing ligaments
Articular capsule and ligament have?
Many nerve endings
Blood vessels that allow synovial fluid
Fatty pads between fibrous capsule
Disc/wedge (menisci) improves what in synovial joint?
BONE FIT
Bursae
flattened, fibrous sacs lined with synovial membranes and containing synovial fluid
Bursae is not?
part of joint
Where are Bursae common?
where ligaments, muscles, skin, tendons, or bones rub together
Tendon sheath
elongated bursa that wraps completely around a tendon
Synovial joints stability determined by?
Articular surfaces
ligaments
muscle tone
Articular surfaces stability
shape determines what movements are possible
Ligaments
unite bones and prevent excessive or undesirable motion at 6%
Muscle tone is accomplished how?
muscle tendons across joints acting as stabilizing factors
Tendons in muscle tone?
kept tight at all times by muscle tone (shoulder jt)
The two muscle attachments across a joint are?
origin
insertion
origin
attachment to the immovable bone
insertion
attachment to the movable bone
During contraction, what happens?
insertion moves towards the origin
synovial joints range of motion
movement described in the directional terms relative to line/axes around which part moves
Nonaxial
no axis around which movement occurs
uniaxial
movement in one plane
biaxial
movement in 2 planes
mulitaxial
movement in or around all 3 planes
C1 and C2 allow one to say?
No
Carpals slide against each other is example of what??
nonaxial
Rotation of head, flex/ext of forearm example
uniaxial
flex/ext of leg and some rotation example
biaxial
clavicles movement is example of
multiaxial
What are 3 different types of movements??
gliding
angular
rotation
Gliding movement
one flat bone surface glides/slips over another similar surface
Intercarpal and intertarsal joints, and between the flat articular processes of the vertebrae is example of what movement?
Gliding
Angular movement
reduction or increase in angle of articling parts Flex/Ext Dorisflexion and plantar flexion abd/add circumduction
Flexion
bending movement that decreases the angle of the jt
extension
reverse of flex, jt angle is increased
Dorsiflexion and plantar flexion
up and down movement of the foot
ABDuction
movement away from midline
ADDuction
movement toward the midline
Circumduction
movement describes a cone in space
rotation movement
the turning of a bone around its own long axis
Between first two vertebrae is an example of what?
rotation movement
hip and shoulder joints is example of what ?
rotation movement
Special movements
Sup/pronation inversion and eversion protraction/retraction elevation and depression opposition
Synovial joints have common feature but not?
structure
synovial joints movement
is based on shape of articulating structure
how many major categories of synovial its?
6
Plane (synovial) Joints
articular surfaces are essentially flat
Plane its allow only?
slipping or gliding movements
nonaxial joints are an example of what synovial jt?
plane joints
Hinge (syn) Jts
Cylindrical projections of one bone fits into a trough-shaped surface on another
Hinge joint motion
is along a single plane
Hinge joints are
uniaxial joints that permit flexion and extension only
elbow and interphalangeal joints are example of what synovial jt?
hinge jt