Forearm and Wrist Flashcards
what is the antebrachium?
forearm (ulna and radius)
what is the carpus?
wrist
what is the pollex/pollicis?
thumb
what is the digiti minimi?
pinky
what does brevis mean?
the shorter one
which surfaces are dorsal/palmar?
dorsal = top of hand
palmar = palm side
what carpal bones make up the proximal row?
scaphoid, lunate, triquetrum, pisiform
what carpal bones make up the distal row?
trapezium
trapezoid
capitate
hamate
what type of bone is the pisiform?
sesamoid
what is the largest carpal bone?
capitate
what do the hook of the hamate and the pisiform make?
Guyon’s canal
what type of joints are between the carpal bones?
plane-gliding joints
what is the primary job for the action of the hand?
grasping/releasing for uniform or irregularly shaped objects
the flexor retinaculum of the wrist is also known as the…
volar ligament
what is the job of the volar ligament?
holds all the tendons in place on the anterior wrist
what are the two muscles that run through the carpal tunnel?
flexor digitorum superficialis
flexor digitorum profundus
which nerve is commonly involved in pathology problems? how so?
the median nerve
the median nerve gets compressed if the volar ligament gets tight
how is the carpal arch formed?
the base is formed medially by the pisiform and the hook of the hamate , laterally by the tubercles of the scaphoid and trapezium
what connects the space between the medial/lateral sides of the base of the arch?
the flexor retinaculum
what is the benefit of the two sesamoid bones on the thumb?
it is good for grip by providing a strong grip – really brings the thumb in
what are the four wrist joints?
distal radio-ulnar
radial-carpal
intercarpal
midcarpal
what is the primary wrist joint?
radio-carpal joint
what type of joint is the distal radio-ulnar joint?
pivot joint
what does the distal radio-ulnar joint allow?
pronation / supination of the forearm
what shape is the distal radio-ulnar joint?
L-shaped
what does it mean if your wrist consistently clicks with little continuous movements?
there is damage to the articular disc , cartilage has been torn
what bones do the distal radius and distal surface of ulnar articular disk articulate with?
scaphoid, lunate, triquetrum
where does the radial collateral ligament originate and attach to?
radial styloid to scaphoid tubercle
where does the ulnar collateral ligament originate and attach to?
ulnar styloid process to triquetrum and pisiform
all collateral ligaments provide support in the BLANK plane
frontal
where does the palmar ulnocarpal ligament originate and attach to?
distal ulna to lunate and triquetrum
where does the palmar radiocarpal ligament originate and attach to?
distal radius to proximal row of carpals and capitate
what is the role of the palmar radiocarpal ligament?
keeps the radius and hand together during supination
where does the dorsal radiocarpal ligament originate and attach to?
distal radius to proximal row of carpal bones
what is the role of dorsal radiocarpal ligament?
keeps the radius and hand together during pronation
what is the benefit for the joints of the carpal bones being plane-gliding joints?
contributes to the ability for grasp and release
where are the intercarpal and interosseus intercarpal ligaments located?
in between the carpal bones and bases of metacarpals
where is the midcarpal joint?
between proximal and distal rows of carpal bones
what does the midcarpal joint allow?
allows the distal row to move on the proximal row when in full grasp for heavy things
participates in all wrist movements to some extent
which finger is the reference point for the other fingers with abduction/adduction?
the middle finger
what point of reference does the middle finger follow?
the regular midline of the body
what type of joint is the thumb?
saddle joint
is the thumb saddle joint concave or convex?
both
what PLANE does flexion/extension of the thumb occur in?
frontal plane
what PLANE does abduction/adduction of the thumb occur in?
sagittal plane
what AXIS does flexion/extension of the thumb occur in?
sagittal axis
what AXIS does abduction/adduction of the thumb occur in?
frontal axis
what is opposition of the thumb?
movement in the saddle joint so that the thumb touches the tips of the other fingers
what is repositioning of the thumb?
bringing the thumb back to anatomical position
where does the median nerve run through?
runs down the flexor forearm –> the carpal tunnel // underneath the volar ligament
where does the ulnar nerve run through?
Guyon’s canal
what is the radial nerve a direct branch level nerve off of?
the posterior cord
where does the radial nerve run?
posterior arm –> extensor forearm –> dorsal surface of the wrist
what does the median nerve innervate on the skin?
on the palmer side:
the thumb, index, middle, and lateral side of ring finger
on the dorsal side:
the tips of the thumb, index, middle, and medial side of the tip of the middle finger
where does the ulnar nerve run?
on the palmar side
does the ulnar nerve provide sensory or motor innervation?
both
motor innervation (deep branch)
sensory innervation (superficial branch)
where does the ulnar nerve provide sensory innervation?
on the palmar side:
the ulnar side of the hand including the entire pinky and lateral side of the ring finger
on the dorsal side:
ulnar side of the hand including the entire pinky and MOST of the ring ringer EXCEPT the medial side of the tip of the ring finger
what is the radial nerve responsible for?
wrist extension
where does the radial nerve come off of and run through?
the posterior cord and runs down the dorsal part of the wrist
what is the only part of the radial nerve that enters the hand?
the superficial branch
where does the radial nerve provide sensory innervation?
on the palmar side:
dorsolateral aspect of the palm
on the dorsal side:
entire thumb, half of index and ring fingers, and medial half of the hand stopping at the wrist
what does the flexor retinaculum do?
connects carpal bones on the palmar surface
forms roof of carpal tunnel
holds finger flexor tendons in place
what does the EXTENSOR retinaculum do?
attached to bones via septa forming separate compartments for tendons
the median nerve innervations all the flexor muscles except these two:
flexor carpi ulnaris
flexor digitorum profundus
what is pronator teres syndrome?
median nerve compression between the two heads of the pronator teres
