Joints (articulations) Flashcards
joints also known as
articulations
what is true for every bone
every bone is connected to at least 1 other bone
functional classifications of joints. how are they classified? what are the types?
classified by how much motion they allow
- synarthrosis
- amphiarthrosis
- diarthosis
after functional, how are they classified?
structural classification
classified by structure features
how are the structural classifications split up?
fibrous joints
cartilaginous joints
synovial joints
what do fibrous joints include?
- joined by dense regular collagenous connective tissue
- NO joint space btwn articulating bone
- Can be synarthrosis or amphiarthrosis
types of fibrous joints (3)
Sutures
Syndesmosis
Gumphosis
what do sutures include?
(fibrous joint)
- joined by short fibers, immovable joints
- EX: bones of skull
what does syndesmosis include?
(fibrous joint)
- joint by short ligaments
- small amount of movement
- EX: btwn tibia & fibula, ulna & radius
what does gumphosis include?
(fibrous joint)
- joined by short ligament, immovable
- EX: btwn tooth & bony socket (why so hard to pull teeth out)
Types of cartilaginous joints (2)
symphysis
synchondrosis
what does symphysis include?
(cartilaginous joint)
- flat disc or plug of FIBROcartilage
- amphiathrosis
- EX: intervertebral joints, pubic symphysis
what does synchondrosis include?
(cartilaginous joint)
0-bones connected by HYALINE cartilage
-synarthrosis
-EX: ribs & sternum, epiphyseal plates
how are synovial joints described?
- bone ends separated by joint cavity
- joint surface enclosed in articular capsule (connective tissue)
- freely movable but less stability
- most body joints
structural elements of synovial joints (6)
- joint cavity
- articular cartilage
- synovial fluid
- avascular
- articular capsule
- adispose tissue, nerves, & blood vessles
what are the support structures in synovial joints?
ligaments
tendons
bursa
difference between the 3 support structures in synovial joints?
ligaments- links BONE to bone
tendons- connects MUSCLE to bone
bursa- synovial fluid filled psace btwn movable parts (protects joint)
classes of synovial joints (4)
where does the movement occur? around?
synovial joint movement occurs in different planes around an axis
- nonaxial joints
- uniaxial joints
- biaxial joints
- multiaxial joints
describe a nonaxial joint
example?
motion occurs in 1 OR MORE planes not around an axis
-EX: between carpals
describe a uniaxial joint
example?
motion occurs around 1 axis
-EX: elbow joint
describe a biaxial joint
example?
motion occurs around 2 axes
-EX: proximal phalanges & metacarpals
describe a multiaxial joint
example?
motion occurs around 3 axes
-EX: shoulder
types of synovial joints? (6)
gliding or plane hinge pivot ball & socket condyloid saddle
what does gliding or plane include?
(synovial joint)
- btwn flat surfaces of 2 bones
- nonaxial
- EX: intercarpals (btwn carpals & metacarpals, btwn wrist bone), intertarsals, vertebrae
what does hinge include?
(synovial joint)
- rounded (convex surface) of 1 bone fits into a concave surface of other bone
- EX: elbow (and knee, like hinge on a door)
what does pivot include?
(synovial joint)
- round end of 1 bone rests in shallow groove of another bone
- uniaxial- pivots or rotates
- EX: btwn axis/atlas & radius/ulna (when turning head, first vertebrae called atlas, second is axis)
what does condyloid include?
(synovial joint)
- convex surface of 1 bone fits into shallow concave surface of another bone
- biaxial
- EX: occipital/atlas (nod & shake head) , metacarpals/phalanges (move finger out & up/down)
what does saddle include?
(synovial joint)
- both bones have both a concave & convex region
- biaxial
- EX: btwn thumb metacarpals/ wrist bone, sternum/clavicle
what does ball & socket include?
(synovial joint)
- spherical part of 1 bone fits into cuplike depression of the other bone
- multiaxial
- EX: shoulder, hip
movements at synovial joints (7)
what does this mean? motion?
specific types of angular motion
- flexion
- extension
- hyperextension
- abduction
- adduction
- curcumduction
- rotation
what is flexion?
angular motion
DECREASES angle btwn articulating bones by bringing bones closer to one another
(EX. bicep flex)
what is extension?
angular motion
INCREASES angle btwn articulating bones, articulating bones move away from one another
(EX. wave hand formation)
what is hyperextension?
angular motion
extension BEYOND anatomical position of joint
(EX. waitress)
what is abduction?
angular motion
motion of a body part AWAY from midline of body or another reference point
(EX. jumping jacks going to form X)
what is adduction?
angular motion
motion of a body part TOWARDS midline of body or another reference point
(EX. jumping jacks to start position)
what is circumduction?
angular motion
freely movbeable distal bone moves on a fixed proximal bone in a CONE-SHAPED MOTION; combination of flexion-extension & abduction-adduction
(EX. fast pitch pitcher’s wind up circle)
what is rotation?
nonangular motion
one bone rotates on an imaginary line running down its middle longitudinal axis
(EX. ballet, 1st->2nd position)
special movements at synovial joints (12)
- opposition -reposition
- depression -elavation
- protraction -retraction
- inversion -eversion
- dorsiflexion -plantarflexion
- supination -pronation
what is opposition and reposition?
opposition: opposition of thumb at first carpometacarpal joint allows thumb to MOVE ACROSS PALMAR SURFACE
repositon: reposition is OPPOSITE MOVEMENT that returns thumb to ANATOMICAL position
BOTH INVOLVE THUMB MOVEMENT
what is depression and elevation?
depression: movement of a body part in an INFERIOR direction (below another body part/ towards the feet)
elevation: moves a body part in a SUPERIOR (toward the head/top)
EX. depression- drop jaw, shoulder down
elevation- close jaw, shrug shoulders
what is protraction and retraction?
protraction: moves a body part in an ANTERIOR (toward front) direction
retraction: moves a body part in a POSTERIOR (toward back) direction
EX. protraction- bottom jaw teeth over maxilla
retraction-over bite
what is inversion and eversion?
inversion: rotational motion where plantar surface of foot rotates medially TOWARD midline of body
eversion: rotates foot laterally AWAY from midline
ex. inversion- in, ankle on big toe side
eversion- out, ankle on pinky toe side
what is dorsiflexion and plantarflexion?
dorsiflexion: movement where angle btwn foot & leg DECREASES
plantarflexion: angle btwn foot & leg INCREASES
EX. dorsiflexion- standing on heel
plantarflexion- standing on toes
what is supination and pronation
supination: rotational movements of wrist & ankle region (counterclockwise for left hand/ ankle)
pronation: rotational movements of wrist & ankle regions (clock wise for left hand/wrist)
-opposite for right hand
Ex. QUEEN WAVE
anatomical position is supination
Functions of joints? (2)
hold bones together
allow skeleton flexibility to move
