wrist complex (test 2) Flashcards
what makes up the wrist complex
radiocarpal and midcarpal joint s
the wrist complex is a ___ compound joint
2
the wrist complex contributes to controlling the ____ _____ relationship in multiarticular hand muscle
length tension
the wrist complex is a ____ joint and has ___ DOF
biaxial
2
what are the motions of the wrist and what axis are they on
flexion/extension - coronal axis
rad/ ulnar dev - AP axis
how many degrees of flex/ext is there at the wrist complex
flex: 65-85
ext: 60-85
how many degrees of rad/ulnar dev is there at the wrist complex
rad: 15-21
ulnar: 20-45
what is the radiocarpal joint structure formed by proximally and distally
prox: radius + TFCC disc
distal: scaphoid, lunate , triquetrum
the lateral radial facet articulates with w carpal
scaphoid
the medial radial facet articulates with w carpal
lunate
the TFCC articulates with w carpal
triquetrum
the radius is ____ and angles _____
oblique
volvarly/ulnarly
the TFCC is connected medially via what ligaments
dorsal and volar radioulnar lig
the TFCC connect distally to what tendon, what carpals and what metacarpal
ECU tendon
triquetrum and hamate
base of 5th MC
what is the proximal row of carpals of the radiocarpal joint
scaphoid lunate triquetrum
the proximal carpal row is connect by the _____ interosseous and ____ interosseous ligaments
scapholunate
lunotriquetral
____ is in the proximal carpal row but not supporting the radius
pisiform
what does the pisiform work as
a seasmoid bone to increase the moment arm of the FCU
which is sharper and acts an an incongruent joint ? the distal or proximal radiocarpal segment
distal
how much axial load does the scaphoid and lunate receive ? TFCC?
80~
20~
what is ulnar negative variance ? ulnar positive variance ?
short ulna
long ulna
if someone has a short ulnar what disease can they have
keinbocks disease ( necrosis of the lunate)
if someone has a long ulna is can lead to what type of FX
radial
Most ligaments and muscles that cross radiocarpal joint also contribute to stability of _____ joint
midcarpal