Hand and Wrist Flashcards
(98 cards)
1
Q
how many intrinsic and extrinsic muscles of the hand
A
19 intrinsic
20 extrinsic
2
Q
main function of the wrist
A
fine tune position of the hand
3
Q
three main roles of the hand
A
expression and communication
protection
sensory
4
Q
how many bones of the whole wrist hand complex and what are the main groups
A
radius/ulna
carpals
metacarpals
phalanges
5
Q
three parts of the distal ulna
A
ulnar styloid process
fovea - attachment for the disc
pole
6
Q
what is the function of the pole of the ulna
A
articular surface for the TFCC
7
Q
three main features of the distal radius
A
distal surface
radial styloid process
ulnar notch
8
Q
what is landmark of the radius where it interacts with the ulna
A
ulnar notch
9
Q
function and location of listers tubercle
A
dorsal distal aspect of the radius
it is a pulley, redirect action of extensor digitorum longus and extensor indices on radial side
redirects action of extensor policies longus on the ulnar side
10
Q
name the bones of the hand
A
scaphoid lunate triquetium pisiform trapezium trapezoid capitate hamate
11
Q
shape of pisiform and what inserts here
A
sesamoid, flexor carpi ulnaris
12
Q
what is unique about the capitate
A
central position of the hand, axis of the hand
13
Q
how many phalanges for each of the digits
A
thumb: two
digits 2-5: three
14
Q
shape of base of phalanges
A
biconcave, smaller articular surface than head
15
Q
shape of heads of phalanges
A
bicondylar
16
Q
how many bones and joints in the wrist complex
A
15 bones
1`7 synovial joints
17
Q
movements and type of joint: distal radioulnar
A
uniaxial pivot joint
pronate/supinate
18
Q
three structures that connect the distal radioulnar joint
A
TFCC, obliques fibres of the distal interosseous membrane, radioulnar ligaments
19
Q
movements and type of joint: radiocarpal
A
ellipsoid synovial, 2 DOF
flex/ex, radial and ulnar deviation
20
Q
what is articulating with what at the radio carpal joint
A
distal radius with scaphoid and lunate
21
Q
what the TFCC articulate with at the radoiocarpal joint
A
ulnar stylus and triquetrium
22
Q
what types of joint are the mid carpal joints and what movements do they do (compound articulation, two parts to to this)
A
synovial plane joints
Planar laterally: scaphoid, trapezium, trapezoid
Condylar medially: scaphoid, lunate, triquetrium, capitate and hamate
general flex/ex, ulnar/radial deviation
23
Q
what type of joint is intercarpal and what it is between
A
joint between bones of proximal and distal rows
plane synolvia joints, allowing for gliding movements
24
Q
what is the arch in teh hand formed by (general structures)
A
carpals, metacarpals, and ligaments
25
carpometacarpal joints 2 to 5
- which have the movement movement (how much)
- which have the least movement
minimal at 2nd and less at third
4th = 10-15 degress
5 = 25-35 degrees
26
function of movements at the carpometacarpal joints 4 and 5
allow transition of the hand from flat to fist
27
1st carpometacarpal: type of joint, between what bones
synovial saddle
| between base of 1st MC and trapezium
28
movements of teh 1st CMC
flex, ex, abduction, adduction, opposition, repositioning
29
metacarpalphalangeal joints: type, movements
synovial condyloid with 2 DOF (flex, ex, ad, ab)
30
what are the head of the metacarpals covered with
articular cartilage
31
what are the bases of the metacarpals extended with with
fibrocartilaginous volar plates
32
interphalangeal joints: type, movements
synovial hinge, flex/ex
33
what two structures to DIPs and PIPs have that help them move as well and reinforce them
volar plates, check rein ligaments
34
what is volar plate
- structure
- attaches to?
- motion through joint motion
- function
- prevents
thin capsule proximally and thick capsule distally
attaches to distal phalanx and collateral ligaments
as joint flexes, volar plate slides proximally UNDER MC with a folding of its membrane
allows for large ROM over small surface area
prevents hyperextension and Doral subluxation
35
distal radioulnar ligaments = O, I, A
O: ulnar notch of radius
I: ulnar styloid process and ulnar fovea
A: part of the TFCC that stabilizes the distal radioulnar joint
36
radial collaateral ligament:
| O, I, function
O: radial styloid process
I: scaphoid and lunate
Function: restrict ulnar deviation, lateral stabilization of the radial wrist
37
ulnar collateral ligament: O, I, Function
O: ulnar styloid process
I: pisiform and triquetrum
Function: restrict radial deviation, lateral stabilization of ulnar wrist
38
Radoiocarpal ligaments - palmar: O, I, function
O: anteroinferior radius, radial styloid process, palmar anteromedial ulna
I: palmar surface of scaphoid, lunate, capitate, triquetrum
A: volubly stabilize radius to carpals, limit excessive wrist extension
39
Radoiocarpal ligaments - dorsal: O, I, function
O: posterioinferio radius
I: dorsal surface of scaphoid, lunate and triquetrum
A: dorsally stabilize radius to carpal, limits excessvie wrist flexion
40
What is the TFCC made of
complex composed of articular disc, menisci homologue, ulnocarpal ligaments, dorsal and volar distal radioulnar ligaments, sheath of extensor carpi ulnaris and prestyloid recess
41
where des TCFF insert
distally into triquetrum, hamate and base of 5th metacarpal
42
functions of TFCC
load absorption and transmission
| stabilize distal radioulnar joint
43
axial loading of wrist is split into what percent onto radius and ulna
82% radius, 18% ulna
44
where do ulna carpal ligaments originate
from the fovea
45
how much does pronation increase ulnar variance
1mm
46
how much does grip increase island variance
4mm
47
what is the flexor retinaculum
- attachments
- function
- point of origin for what
"carpal tunnel"
- attached to triquetrum, pisiform, hook of hamate, tubers of trapezium and scaphoid
- create passage for tendon of flexor pollicus longs, flexor digitorum superficial and profundus and median nerve
- point of origin for thenar eminence
48
what is teh extensor retinaculum
- what does it restrict
- what reduces friction
thickening of dorsal forearm fascia
subdivided into compartments
restricts tendon bowstring during wrist hyperextension
tendon wrapped in synovial sheath to reduce friction
49
medial and lateral collateral of the fingers: O, I, function in flexion and extension
O: head of metacarpal phalanx
I: base of neighbouring phalange
Flex: tight, assist with grip
Ex: loose: allow ab/ad at MCP
50
deep metacarpal transfer ligament: attachments, function
attaches for metacarpal head 2-5, volar plates
| allows for flexible metacarpal arch
51
what muscles on ulnar and radial side of thumb attach to volar plate and control thumb
Ulnar: adductor polices and first dorsal interossi tendon
Radial: flexor policies Brevis and abductor Brevis
52
what is the shape of teh structure that facilitates pinching precision
sesamoid
53
when elbow flexed greater than 15 degrees, how does the line fo pul and action of elbow wrist extensors changes, what muscle is best at this
anterior elbow axis transitions and wrist extensors can become elbow flexors
extensor carpi radialis longus can be and effective elbow flexor
54
wrist flexors originate where
medial epicondyle of elbow
55
name the primary wrist flexors
```
flexor carpi radialis
flexor carpi ulnaris
flexor digitorum superficualis
flexor digitorum profundus
palmaris longus
flexor pollicis longus
abductor pollicis longus
```
56
can wrist flexors acts at elbow extensors? how so compared to wrist extensors?
they can if elbow is flexed, not as powerful s wrist extensors though
57
what muscle interactions causes ulnar and radial deviation
extensors and flexors work synergistically
ECU, FCU together!
ones further from centre axis help more
58
main function of extrinsic muscles of finger
strength and gross motor control
59
which muscle extends all teh fingers
extensor digitorum
60
flexor digitorum superficialis: how does this muscle split and where do the split ends insert
split into two, which each split into two tendons
2 superficial tendons go to digits 3 and 4
2 deeps tendons go to digits 2 and 5
61
location of flexor digitorum profundus, what does it go under
anterior ulnar side of forearm
| goes unser FDS and splits into four tendons
62
four main thumb extrinsic muscles and function
```
flexor pollicus longus
- primary thumb flexor, only IP flexor
extensor pollicus longus and Brevis
- extension synergists
abductor pollicius longus
- main thumb abductor
```
63
function of intrinsic hand muscles
fine motor movements
64
what is the group name of the thumb intrinsic muscles
thenar muscles
65
what is the group name of the pinky pinger muscles
hypothenar
66
function of the Interossei muscles
adduct fingers
67
function of lumbricals
flex MCP and extend IP
68
what is the function extensor hood and flexor tendon sheath
structure of the fingers and thumb designed to
- hold flexor and extensor tendons in place
- allow them to move and glide
- guide direction of pull
69
what is the extensor mechanism of the fingers made up of
intrinsic muscles
long finger extensors
long finger flexors
mechanism made up of distal tendinous attachments, retinacula and ligaments
70
what is the purpose fo the extensor mechanism
allow extension of digits in multiple finger positions and permit full flexions
71
what is trigger finger
```
dysfunction of the flexor pulley
module or thickened tendon sheath
glide through pulley interrupted
```
72
flexion is made up of how much movement at radoiocarpal and how much at mid carpal joint
50 degrees at radoiocarpal and 35 degrees at mid carpal joint
73
extension is made up of how much movement at radoiocarpal and how much at mid carpal joint
50 degrees at midcarap, 35 degrees and radoiocarpal
74
axis for flex ex of the wrist is
capitate
75
closed position for the wrist
full wrist extension
76
how much flexion at MCP joints
90 degrees
77
closed packed position of MCPS
full flexion
78
up to how many degrees extension at MCPs
45 degrees
79
how much ad and ab at MCP when MCPs are extended
| how much when flexed
20 degrees when extended for both
| almost none when flexed
80
how much flex and ex for thumb
```
flex = 45-60
ex = 0-20
```
81
how much flex at ex at IP joints
120 flex
| 0 ex
82
closed packed position of Thumb
full extension
83
closed packed position of MCP and IP 2-5
full flexion
84
what are power grips of the hand
incorporate the entire hand
used for grasping activities
involved in holding an object between partially flexed fingers and palm while thumb provides pressure
85
what are the four power grips of the hand
fist, cylindrical, hook, spherical
86
what are precision grips
used for accuracy and refinement, object manipulation
| thumb abducted, ready to oppose
87
types of precision grips
tip to tip pinch
lateral key pinch
three prong Chuck
88
grip strengt males vs females and dominant vs non dominant
males average 2x greater than females of similar age
| 6% stronger on dominant side
89
what wrist position decreases grip strength
wrist flexion
90
optimal wrist position for grasping
20-35 degrees extension with slight ulnar deviation
91
what is mallet finger
trauma to DIP
generally caused by an impact force to the fingertip
avulsion of the lateral bands of the extensor tendon
permanent flexion of teh DIP
92
what is boutinneir deformity
central slip of extensor digitorum at middle phalanx
flexed position of PIP results in lateral band being place posterior to teh axis of motion for the DIP causing hyperextension
93
what is swan neck deformity
primarily associated with arthritis
weakened fo teh hand intrinsics resulting in the PIPS hyperextending
causes lateral slop of the extensor tendon to shift dorsally relative to the joint
94
what is Dupuytren's contracture
palmar fascia is thickened with fibrosis
primarily at digits 3 and 4
pits and modules, tendon not directly involved
95
what is Volkmanns contracture
ischemic flexion deformity
from ischemic necrosis of the forearm flexors
pressure injury with forearm compartment
muscles replaced by contracted fibrous tissue
96
radial nerve injury causes
effects extensors
| wrist drop - effective grasp not possible
97
median nerve injury causes
innervate most flexors (not FCU)
hand of benediction
ape hand (inability to oppose)
98
ulnar nerve injury causes
supplies most small muscle of the hand except FDP/lumbrical split/thenars
ulnar claw
- injure can occur at forearm or wrist
fourth and fifth digits mostly affected
