wrist Flashcards
What are the joints in the wrist
-radiocarpal: between carpals and radius
-midcarpal joint: between 1st and 2nd row of carpals
-intercarpal joints: between the carpals in the row
what does the dorsal tubercle of the radius do
increases the internal moment arm for Extensor pollicis longus
ulnar tilt
created by the radial styloid process being more distally
palmar tilt
created by the dorsal radius extending out and creating a “roof”
Triangular fibrocartilage complex
-takes away from carpal ulnar joint (not there)
-ulnar collateral ligament, articular disc, palmar ulnocarpal ligament
Ulnar collateral ligament
prevents radial deviation
radial collateral ligament
limits ulnar deviation
Dorsal intercarpal ligement
within the carpals and limits flexion
short dorsal ligaments
in the distal row of carpals
limits flexion
dorsal radoiocarpal ligament
attaches the radius to the carpals
limits flexion
short palmar ligament
in the distal row
limits extension
transverse carpal ligament
palmar side, in the carpals
limits extension
palmar radoiocarpal ligament
radiocapitate, radiolunate, radioscapholunate
limits extension
ulnocarpal complex (triangular fibrocartilage complex (TFCC)
ulna collateral ligament
palmar ulnocarpal ligament
articular disc
-takes the ulna out of the wrist joint/does not articulate with carpals
-absorbs about 20% of shock/force and redistributes it
osteokinematic motions of the wrist and ROM in degrees
flexion: 0-70/85
extension: 0-60/75
radial deviation: 0-15/20
ulnar deviation: 0-35/40
athrokinematics of the radius and proximal row of carpals during extension
dorsal roll and palmar glide
athrokinematics of the radius and proximal row of carpals during flexion
palmar roll and dorsal glide
athrokinematics of the radius and proximal row of carpals during ulnar deviation
ulnar roll and radial glide
athrokinematics of the radius and proximal row of carpals during radial deviation
radial roll and ulnar glide
describe ligament tension during RD and UD
there is a lag between the proximal and distal arrow of the carpals
-ulna deviation: outermost on ulnar side is on slack then the middle ligament on ulna side is taut and then medial radial ligament is on slack and then outer radial is taut
-radial deviation: outer most on radial side is on slack then the middle radial ligament is taut and then medial ulnar ligament is on slack and then outer most ulnar ligament is taut
voler intercalated segment instability
ligaments between lunate and radius are torn
the lunate will dislocate towards palmar side
(compressive force in wrist extension)
dorsal intercalated segment instability
ligaments between the lunate and radius are ton and the lunate will dislocate towards the dorsal side
Scaphoid fractue
-scaphoid ligament will most likely be torn and the blood supply will be disrupted and therefore part of the bone will die
why are the lunate and scaphoid the most vulnerable
not all the carpal bones are even and the lunate and scaphoid take the force first
what is the best wist position for the greatest grip strength
about 30 * of wist extension (mid range)
Which have the greatest toque production the flexors or extensors and then the ulnar deviators or radial deviators
flexors
radial
Degree of ulnar variance/what are the complications?
-will change the muscle capacity
-will change force production
-when you change the articulations you will change the roll and gilde
palmar tilit normal
10* is a normal palmar tilt
colles fracture
-distal radius
-often results in “dinner fork deformity”
-displacement of carpal bones towards the posterior
