Wrist and Hand Flashcards
where is the thenar eminence located?
thumb side (radial side)
where is the hypothenar eminence located?
pinky side (ulnar side)
what do the hypothenar and thenar eminences contribute to?
better grasp
how are the palmar flexion creases formed?
by the amount of movement you do
what is the CMC joint?
carpometacarpal joint
carpal bone to base of metacarpal bone
what is the MCP joint?
metacarpophalangeal joint
head of metacarpal to base of proximal phalanx
what is the PIP joint?
proximal interphalangeal joint
head of proximal phalanx to base of middle phalanx
what is the DIP joint?
distal interphalangeal joint
head of middle phalanx to base of distal phalanx
where are the peripheral joints?
first, fourth, and fifth metacarpals
where are the central joints?
second and third metacarpals
what is the most important aspect of active grasp?
the mobility of the CMC joint
what kind of shape do the carpal bones/palmer surface of the hand make, and what is it good for?
bowl shaped (concavity)
good for grip
is there as much movement at the CMC joints of the second and third metacarpal as there is at the first, fourth, and fifth?
no, the peripheral joints provide more movement
what type of joint is the CMC joint of the thumb?
a sellar/saddle joint
what makes a joint a sellar/saddle joint?
there ALWAYS has to be a third movement involved
in terms of the thumb, it’s flex/ext, abd/add, AND opposition
what does having the ability to oppose differentiate for us?
separates us from other species
where are the two axis of the CMC joint of the thumb?
frontal axis through the tripezium
sagittal axis through the base of the first metacarpal
what shape is the MCP joint?
condylar shape – concave on top of convex
when in FLEXION, are the collateral ligaments taut or looser?
taut
when in EXTENSION, are the collateral ligaments taut or looser?
looser
what is another term for the palmar ligaments?
the palmar plates
what is the palmar ligament made up of?
fibrocartilaginous pads