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
Most ligaments and muscles that cross radiocarpal joint also contribute to stability of midcarpal joint, however what muscle is an exception and where does it attach
FCU
atttaches to the pisiform , hook of hammy , base of 5th MC
proximally the midcarpal joint structure articulates with what carpal bones
scaphoid
lunate
triquetrum
distally the midcarpal joint structure articulates with what carpal bones
trapezium , trapezoid, capitate and hammate
the midcarpal joint structure has a _____ _____ configuration
concave -convex
are the dorsal or volar ligaments of the wrist complex thicker/stronger
volar
what ligaments connect carpals to radius/ulna proximally or metacarpals distally
extrinsic ligaments
which ligaments interconnect carpals themselves
intrinsic (within the hand)
what are the volar radio-carpal ligaments
Radioscaphocapitate, radiolunate, and radioscapholunate
what volar carpal ligaments provides extension of volar radiocarpal lig
radial collateral lig
what is part of the ulnocarpal ligament complex which is part of the volar carpal ligaments
TFCC, ulnolunate ligament, and ulnar collateral ligament
what are the extrinsic volar carpal ligaments
volvar radiocarpal ligaments
radial collateral lig
ulnocarpal ligament complex
what are the intrinsic volar carpal ligaments
scapholunate interosseous lig
lunotriquetral interosseous lig
v-deltoid
what does the scapholunate interosseous lig do
maintains scapho-lunate stability
what does the lunotriquetral interosseous lig do
maintains lunate-triquetral stability
the dorsal radiocarpal ligament converges on the ____
triquetrum
what ligament Possibly helps to offset sliding of proximal carpal condyle on inclined radius
dorsal radiocarpal ligament
the dorsal intercarpal ligaments courses horizontally from what carpal bones
triquetrum, lunate, scaphoid, and trapezium
what does the dorsal radio carpal lig and the dorsal intercarpal lig form together ?
horizontal V” to stabilize scaphoid during wrist ROM
does the volar or dorsal carpal ligaments become tight during wrist extension
dorsal
what is the mechanical link between the radius and distal carpals
proximal carpal row
the proximal carpal row is considered a ___ segment
intercalated
what carpal is the keystone to the wrist
capitate
what carpal is thought ti be center of rotation of wrist complex
capitate
what is the biggest carpal bone and contacts 7 other carpals
capitate
what are the 7 carpal bones that contact the capitate
lunate
scaphoid
hammy
trapezoid
2nd,3rd, 4th MC
if the wrist is in full flexion how does ext begin
distal carpal row glides posteriorly on the proximal row to neutral which is when capitate and scaphoid become close packed
when the wrist begans extension the distal carpal row glides posteriorly on the proximal row to neutral which is when capitate and scaphoid become close packed and then what happens
the distal row and scphoid move on lunate and triquetrium to 45 degrees when scaphoid and lunate lock
during extention the distal carpal row glides posteriorly on the proximal row to neutral which is when capitate and scaphoid become close packed and then the distal row and scphoid move on lunate and triquetrium to 45 degrees when scaphoid and lunate lock.. finallly …
the proximal row extends on radius/disc to fully extent closed packed positon
if the wrist is going into flexion from full extension what is the order of the scaphoid moivng on carpals
- scaphoid moves on radius/disc
2/ scaphoid moces on lunate - scaphoid moves on capitate
in radial deviation the carpals slide how? prox row? distal row?
ulnarly on radius
flexion of proximal row
extension of distal row
closed packed position
during ulnar deviation the carpals slide how ? proximal row? distal row?
slide radially
proximal row ext
distal row flex
is wrist deviation the least when the wrist is in flexion or extension
extension (closed packed)
when the wrist is in flexion the bones are splayed (loose packed)
dorsal intercalated segmental instability comes from ligamentous laxity/tear of the _____ ligament which causes the lunate to ___ or move dorsally , separating the ____ from the ___-
scapholunate
extend
lunate from the scaphoid
progressive degenerative problem from dorsal intercalated segmental instability is called what
scapholunate advanced collapse
volar intercalated segmental instability comes from ligamentous laxity/tear of the _____ ligament which causes the lunate to ___ or move volarly with the ___ seperating ___ from ____
lunotriquetral
flex
flex
scaphoid
lunate from triquetrum
what is the optimal position for the wrist complex
slight wrist EXT and ulnar deviation in order to maximize grip strength
what are the primary volar wrist muscles (flexors)
palmaris longus
flexor carpi radialis
flexor carpi ulnaris
what are the primary dorsal wrist muscles (extensors)
extensor carpi radialis longus
extensor carpi radialis brevis
extensor carpi ulnaris
what is the distal carpal row and the base of the 2nd-5th MC joints called
carpaometacarpal joint
the deep transverse metacarpal ligament tethers what together and what does it limit
tethers 2-4 MC head together and limits abduction
what is the proximal transverse(carpal) arch created by
curve shape of carpals , transverse carpal ligament , and inter carpal ligaments
the proximal transverse arch also forms what
the carpal tunnel
what nerve travels thru the carpal tunnel
median
what hand deformity is a result of carpal tunnel syndrome
bishops hand and ape hand
does the CMC joint have increased mobility on radial or ulnar side
ulnar
what type of joint is the 2-4th CMC joint and how many DOF does it have
plan synovial joint and 1 DOF (flex/ext)
which CMC joint are fixed and stable with the thumb and which move
2nd and 3rd are fixed
4th nd 5th move
what type of joint is the 5th CMC joint and how many DOF does it have
saddle joint with 2 DOF (flex/ext and add/abd)
which arch of the hand is Concavity formed by carpal bones results in proximal transverse arch of palm of hand; and fixed
proximal arch
the distal arch of the palmar arch system is formed from adjustable positions of ___ ,___ and ___ metacarpal heads around a fixed CMC joint at __/___
1st, 4th and 5th
2nd/3rd`
the longitudinal arch of the palmar arch system is ____ to ____ including all the fingers … is it mobile or fixed
proximal to distal
mobile
is the distal arch of the palmar arch system mobile or fixed
mobile
which arch allows the palm and digits to conform to objects during grasp/grip
the palmar arches
the palmar arches allow the palm to have ___ surface contact
max
the palmar arches enhances ____ and increases ___ feedback
stability
sensory
the palmar arch is assisted by what muscles
finger flexors
opponens digiti minimi
flexor carpi ulnaris
how many metacarpalphalangeal joints are there
4
each MCP joint has a ____ head which is ___ and a ___ base of the 1st phalanx ___
concave
prox
convex
distal
what type of joint is the MCP joint and how many DOF
condyloid joint with 2 DOF (flex/ext and abd/add)
in the MCP joint is the capsule taut or lax in extension to allow passive axial rotation of the proximal phalanx
lax
how many collateral ligaments does the MCP joint have
2
if the concave phalanx of the MCP moves on the convex head of the metacarpal they will roll and slide in the ___ direction
same
the volar plate of the MCP joint support the ____ arch
longitudinal
the volar plate of the MCP joint limits _____
hyperextension
the volar plate of the MCP joint resists tensile stress in ____
extension
the volar plate of the MCP joint resist ____ forces from objects
compressive
the volar plate of the MCP joint glides ___ during flexion
down
the volar plate of the MCP joint prevents pinching of ____ tendons
flexor
the collateral ligament proper of the MCP joint is more taut in ___
flexion
the accessory collateral ligament of the MCP joint is more taut in ___
extensions
the collateral ligaments of the MCP is limited in ___ during flex due to collaterals and bicondylar metacrpal head
abduction
there is Fibrocartilage projections into MCP, PIP, and DIP joints from ____
dorsal extensor hood
joint ROM for the MCP joint ranges from each finger but increases ___ to ____
radially to ulnarly
what is the MCP joint ROM during flexion for the 2nd MCP and 5th MCP
90°
110°
where is MCP joint add/abd most available
in extension at the 2nd and 5th MCP joint
what type of joints are the PIP and DIP and how many DOF
true synovial joints with 1 DOF
each PIP and DIP joint has what 3 things
joint capsule
volar plate
2 collateral ligaments
the base of the phalanx has 2 shallow __- facets with a central ridge
concave
does the DIP have any. hyperextension ?
some
what is the ROM for flexion at the PIP and DIP joints
PIP: 100-135
DIP: 80-90
do you have more flexion range of of the DIP and PIP at the ulnar or radial side
ulnar ; tigher grip
finger flexors are dependent on what to counterbalance for good length tension
wrist ext
what type of grip is tool larger on ulnar side for greater length and force
pistol grip
smaller grip ulnarly allows for ____ ROM but ___ force
greater
less
the tendons of the flexors must glide freely thru what
flexor retinaculae , bursa , digital tendon sheaths
what structures tether tendons to hand and prevent bowstringing while bursa and sheaths facilitate gliding
retinaculae structures
the ulnar bursa envelops the ___ and ___-
flexor digitorum profundus
flexor digitorum superficials
the radial bursa covers the
flexor pollics longus
how many annular pulleys are there ? cruciate pulleys ?
5 annular
3 cruciate and a plamar apenurosis pulley
____ filled sheaths promote gliding
synovial
which extrinsic finger extensors all pass under extensor retinaculae and have individual bursa or sheaths
EDC (extensor digitorum communis)
EIP (extensor indicis proprius)
EDM (extensor digiti minimi)
at the MP joint what tendon merges with the extensor expansion hood
extensor digitorum communis
the ___ and the ___ enter into the EDC tendons of the index and 5th allowing independence of those digitis
extensor indicis
extensor digiti minimi
___, ___ & ___ are only MP extensors via their crossing of the MP and
attachment into the extensor hood and sagittal bands (help prevent
bowstringing)
EDC, EI & EDM
EDC, EI & EDM are also synergists for what
wrist extension
which tendon of the extensor mechanism extends the PIP
central tendon
the ___ bands blend into the terminal tendon with triangular ligament and extend the ___
lateral
DIP
Interphalangeal extension requires ___ plus ____ and ___
extensor digitorum communis
interossei and lumbricals
lumbricals come from the ___ tendons to the ___ band
FDP to the lateral bands
where does the oblique retinacular ligament come from and where does it attache
comes from prox phalanx, annular and cruciate pulleys and attaches distally to lateral bands past PIP
the dorsal and volar interossei (DABS and PADS) attache to the sides of the ___ , distally attach to the ___ phalanx and dorsal ___
MC
prox
hood
what tendons are dorsal to MP and pull on the sagittal bands
extensor tendons
simultaneous interphalangeal extension requires active forces from what 3 muscles
DI
VI
lumbricals
isolated extensor digitorum communis causes active and passive what
active MP hypertension with passive IP flexion
Isolated EDC causes active MP hyperextension with passive IP flexion causes what position of the fingers
clawing or intrinsic minus position
___ and ___ extension is interdependent via
extensor mechanism
DIP and PIP
Isolated contraction of interossei and
lumbricals results in MP ___ with IP
___
flexion
extension
So, IP extension can come from active
force of intrinsics or EDC or passive
stretch of EDC with MP flexion; what
contribute to passive tension?
ORLs
if intrinsics are weak (ulnar nerve
injury), splint to fix MP in slight ___
allows EDC to ext IPs
flexion
___ flexes both joints and passively pulls extensor hood up and into
relaxed position
FDP
what happens are the DIP and PIP when ORLs are dorsal to PIP
DIp flex with PIP ext
If FDS flexes PIP, DIP cannot be actively ___ due to distal pull of
the dorsal hood
extended
in the intrinsic finger musculature there are ___ dorsal interossei and ___ volar interossei
4
3
the DI proximal attachemnts act on the ___ and the distal affect the ___ and __
MP
IP and MP
what muscles abd the 5th digit
abductor digiti minimi
When MP is EXT, interossei MA is ineffective for ___ (yet can help prevent clawing) but MA is good
for ____
flexion
abd/add
When MP is FLX, interossei have good MA for ____; collateral ligaments become taut and prevent ____; good grip strength
flexion
ABD/ADD
where is ext weaker in the Ip joints? and why
index and 5th bc only one interossei
where do the lumbricals originate from prox and distally
prox: FDP tenon
dis: lateral band of the extensor expansion
Contraction of Lumbricals tenses the ___ band resulting in PIP and DIP
___
lateral
extension
are lumbricals or interossei more effective in MP extension ?
lumbricals bc of their more distal attachments
describe the intrinsic plus positon
lumbricals and interossei activation without extrinsic finger flexors or extensors
describe the intrinsic minus position
Activation of extrinsic
finger flexors and extensors
w/o lumbricals or interossei
what is the carpometacarpal joint of the thumb called
trapeziometacarpal joint
trapeziometacarpal joint is a ___ joint with ___ DOF and ___ portion near the anterior radial tubercle
saddle
2 (flex/ext and add/abd)
spherical
how much ROM is at the trapeziometacarpal joint during flex/ext and around what axis
motion is parallel to palm but 53° and around the oblique AP axis
how much ROM is at the trapeziometacarpal joint during add/abd and around what axis
motion is perpendicular to palm and 42° and around the oblique coronal axis
how much ROM is at the trapeziometacarpal joint during opposition
17°
the trapeziometacarpal joint is common for what disease
OA
the trapeziometacarpal joint is in closed pack during extreme
add/abd
what motion is opposition sequentially
abd. add. flex
what makes up the thumb MP joint
head of 1st MC with base of proximal phalanx
what type of joint is the thumb MP and how many DOF
condyloid with 2 DOF (flex/ext an abd/add)
what kind of bones is in the thumb MP
seasmoid
what is the function of the thumb MP
add flex range to thumb in opposition
sesamoids in the thumb develop with friction by what age
12
what makes up the thumb IP
head of proximal phalanx with base of distal phalanx
what are the 4 extrinsic muscles of the thumb
flexor pollicis longus
extensor pollicis brevis
extensor pollicis longus
abductor pollicis longus
the EPL, EPB and APL make up what near the thumb
the snuff box (3 extensors)
the extrinsic thumb musculature are subject to ____ insufficiency
active
what are the 4 intrinsics muscles of the thumb ?
OP
ABD PB
FPB
ADD POL
what is grasping of fingers and thumb
prehension
what is power grip used for
open hand , position fingers , grasp object and maintain static grip
cylindrical, spherical , hook and lateral prehension are all examples of what type ofr grip
power
what is precision handling
same as power grip but no static phase
pad to pad , tip to tip , and pad to side are examples of what
precision handling
how many deg is wrist extension
20
how many deg is ulnar dev
10 deg
how many degrees does the MPs go into
45
how many degrees for the PIP and SIP go into
pip : 30
dip: slight flexion
