-
articulation
- aka joint
- any place where two bones come together
- classified by structure and function
-
joint structures
- fibrous
- cartilaginous
- synovial
-
fibrous joint
- no cavity
- bones held together by fibrous connective tissue
- ex: sutures of the skull, distal tibiofibular joint (ankle)
-
cartilaginous joint
- no cavity
- bones held together by cartilage
- ex: ribs to sternum, symphysis pubis
-
synovial joint
- cavity
- always has fluid
- ex: knee, shoulder
-
joint functions
- synarthrotic
- amphiarthrotic
- diarthrotic
-
synarthrotic joint
- no movement
- ex: sutures, gomphosis (teeth/jaw)
-
synchondrosis joint
- synarthrotic
- any immovable joint with hyaline cartilage
- ex: ribs to sternum
-
amphiarthrotic joint
slightly movable
-
syndesmosis joint
- amphiarthrotic
- fibrous joint with more fibrous connective tissue than a suture
- ex: distal tibiofibular joint
-
symphysis joint
- amphiarthrotic
- connecting cartilage is always fibrocartilage
- ex: symphysis pubis, vertebral discs
-
diarthrotic joint
- freely movable
- always a joint cavity
- end of bone covered in hyaline cartilage
- sleeve-like structure extends from periosteum of one bone to periosteum of other
- outside: dense regular CT
- inside: synovial membrane that produces synovial fluid
- meniscus between bones
- bursae cushions joint
-
meniscus
fibrocartilage that holds bones tightly together
-
bursae
sacs filled with fluid that cushion joints
-
gliding joint
- diarthrotic
- ex: intertarsal, intercarpal
-
hinge joint
- diarthrotic
- ex: elbow, knee, finger, ankle, occipital-C1
-
pivot joint
- diarthrotic
- ex: proximal radioulnar
-
saddle joint
- diarthrotic
- ex: carpal-metacarpal of thumb
-
condyloid joint
- diarthrotic
- ex: radiocarpal
-
ball and socket joint
- diarthrotic
- ex: hip, shoulder
-
flexion
decrease angle between 2 bones
-
extension
increase angle between 2 bones
-
hyperextension
extend body part out of anatomical position
-
abduction
move body part away from midline
-
adduction
move abducted body part back to anatomical position
-
circumduction
move body part in a complete circle
-
inversion
soles of feet pointing inward
-
eversion
soles of feet pointing outward
-
dorsiflexion
flex the foot up (toward shin)
-
plantarflexion
flex the foot down
-
rotation
move a body part around a central axis
-
protraction
move a body part forward keeping it parallel to the ground
-
retraction
move protracted part back into anatomical position
-
-
-
elevation
move a body part up
-
depression
move elevated body part back down
|
|
