carpus and hand Flashcards
1
Q
what are the different movements of the wrist?
A
- abduction (radial deviation)
- adduction (ulnar deviation)
- flexion
- extension
2
Q
what are the different movements of the hands and fingers?
A
- flexion and extension of the metacarpal-phalanges joints
- adduction of fingers
- abduction (spreading) of fingers
- flexion and extension of thumb
- opposition of thumb
3
Q
what is the IP joint?
A
- interphalangeal joint
- joint at the tip of the finger
4
Q
describe the **1st carpometacarpal joint **
A
- synovial joint - between the carpal bone and the metacarpal bone of the thumb
- wide range of mvts - most out of all CMC joints
- flexion and extension
- abduction and adduction
5
Q
what is a fracture of the 1st carometacarpal joint called?
A
a bennetts fracture
6
Q
what is the mmemonic for remembering the carpal bones of the hand?
A
- She Likes To Play Try To Catch Her
7
Q
what are the carpal bones in the hand - proximal row, distal row - lateral to medial?
She Likes To Play Try To Catch Her
A
- Scaphoid
- Lunate
- Triquetral
- Pisiform
- Trapezium
- Trapezoid
- Capitate
- Hamate
8
Q
Describe the radiocarpal joint (the wrist)
A
- synovial joint
- distal radius articulating with the scaphoid, lunate and triquetral bone
9
Q
what is the** function of the triangular fibrocartilaginous disc **in the wrist joint?
A
- load bearing structure between the lunate, triquetrum and the ulnar head
- act as a stabiliser for the ulnar aspect of the wrist
10
Q
what is the mid carpal joint?
A
- the articulation between the proximal and distal row of the carpal bones
- synovial joint
11
Q
which carpal bone is most commonly fractured? And how does this happen?
A
- scaphoid bone
- MOI - falling on an outstretched hand - fractures are usually along the axis and may fail to unite
12
Q
what is a complication of a spaphoid fracture?
A
- the scaphoid bone recieves a lot of blood supply - a fracture in this bone could lead to** avascular necrosis **
13
Q
In which direction could the lunate bone dislocate and what nerve could be damaged as a result?
A
- may dislocate anteriorly
- effects the median nerve
14
Q
what are the different layers of the hand?
A
- skin
- **deep fascia **and **palmar aponeurosis **
-
superficial muscle layer - ie thenar and hypothenar muscles
4.** intermediate muscle layer** - lumbrical and long flexor tendons from forearm muscles - deep muscle layer - interossei (palmar and dorsal) and adductor pollicis muscle
15
Q
what is the** palmar aponeurosis**?
A
- central part of the deep fascia in the hand
- highly specialised and thickened structure
- triangular in shape - anchored to the flexor retinaculum
- divides into slips for insertion
16
Q
what is the flexor retinaculum?
A
- fibrous band on the palmar side of the hand near the wrist, it arches over the carpal bones on the hand
- important structure involved in the carpal tunnel
17
Q
what is the carpal tunnel?
A
- narrow passageway found on the anterior portion of the wrist which allows the entrance of several tendons and the median nerve from the forearm into the hand
- formed by 2 layers - deep carpal arch and the flexor retinaculum
18
Q
what are the contents of the carpal tunnel?
A
- tendon of flexor pollucis longus
- four tendons of flexor digitorum profundus
- four tendons of flexor digitorum superficialis
- median nerve
19
Q
once the median nerve passes through the carpal tunnel, what does it brancch into?
A
- divides into 2 branches
- the recurrent branch
- palmar digital nerve
20
Q
what is carpal tunnel syndrome?
what is it and what are symptoms?
A
- compression of the median nerve
- pins and needles in the hand which become worse at night
- patient complains of weakness in the hand and dropping things
- overtime, they can develop wasting of the thenar muscles
21
Q
what might be potential causes of carpal tunnel syndrome?
A
- fluid retention - eg pregnancy etc
- arthritis
22
Q
what are the 4 thenar muscles in the hand?
APB is A Friend Of Police
A
- abductor pollis brevis
- adductor pollucis
- Flexor pollucis brevis
- Opponens Pollucis
23
Q
what is the thenar eminence?
A
the ball or fleshy part of the thumb
24
Q
what nerve innervates the thenar muscles?
A
the median nerve
25
what are the thenar muscles attached to?
* they are attached to the radial side of flexor retinaculum and the adjacent carpal bones
26
what is the hypothenar eminence?
* fleshy region on the palmar side of the little finger
27
what are the 4 hypothenar muscles?
* abductor digiti minimi
* flexor digiti minimi
* opponens digiti minimi
* palmaris brevis
28
what is the hypothenar eminence attached to?
* the ulnar side of flexor retinaculum and the adjacent carpal bones
29
what nerve innervates the hypothenar muscles?
the ulnar nerve
30
what are the 3 long flexor tendons of the hand?
| note the flexor tendons are on the palmar surface of hand - flex wrist
* Flexor digitorum superficialis
* Flexor digitorum profundus
* flecxor pollicis longus
31
what is the flexor pulley system of the hand?
* complex system of the hand that co-ordinates the flexion of the digits (ie fingers)
* consists of the long flexor tendons and their associated flexor tendon synovial sheaths, annular pulleys, cruciate pulleys and oblique pulleys
* main role of this system is to hold the tendons against the phalanges preventing them from pulling away and bowstringing
32
what are the **palmar spaces** of the hand?
* spaces that lie **between the flexor tendons and the fascia **covering the deep muscles in the floor of the palm
* midpalmar space, thenar space, medial fibrous septum and lateral fibrous septum
33
what are the lumbrical muscles and why are they important?
* lumbricals are muscles in the hand
* they are critical for finger mvt and they link the extensors to the flexor tendons
34
what does each lumbrical muscle originate and insert onto?
* each lumbrical muscle originates from a tendon of the flexor digitorum profundus and they pass laterally round each finger and insert onto the extensor hood of the finger
35
what is the action of the lumbrical muscles?
flex MCP joints and extend IP joints
36
what are the radial or lateral lumbrical muscles innervated by?
the median nerve - the digital branch
37
what are the medial (ulnar) lumbrical muscles innervated by?
ulnar nerve - deep branch
38
what are the interossei muscles of the hand?
* muscles located between the metacarpal bones of the hand
* divided into 2 groups - palmar and dorsal
39
in addition to adduction and abduction of the fingers, what do the interosseus muscles also assist with?
they also assist the lumbricals in flexion at the MCP joints and IP joint extension
40
Describe the palmar interossei muscles - what are they, attachments and function
* muscles located anteriorly on the hand - ie the palm
* 3 palmar interossei muscles
* each muscle arises from a medial or lateral side of a metacarpal and attaches onto the extensor hood & proximal phalanx of the finger
* palmar = PAD - they adduct the fingers
41
what nerve innervates the palmar interossei muscles?
the ulnar nerve- deep branch
42
describe the dorsal interossei muscles - what are they, attachments and function
* located on the dorsum of the hand
* there are 4 of them
* each muscle originates from medial or lateral side of MC (2 adjacent MC's) and insert onto the extensor expansions of 2nd,3rd and 4th digits
* they abduct the digits
43
what nerve innervates the dorsal interossei muscles?
the ulnar nerve - deep branch
44
what 3 nerves innervate the hand?
* median
* ulnar
* radial
45
what two arteries does the blood supply of the hand originate from?
* radial and ulnar arteries
* important branches - are the superficial palmar arch and the deep palmar arch
46
what muscles would be affected by an ulnar nerve injury & therefore what mvts might be affected?
* interossei muscles - ie extension of MCP's and flexion of IPs
* 2 medial lumbricals
* hypothenar muscles
47
