Week3Anatomy Flashcards
1
Q
bones of the proximal row (hand)
A
(radial to ulnar, in palmar view) scaphoid lunate triquetrum pisiform
2
Q
bones of the distal row (hand)
A
(radial to ulnar, palmer view) Trapezium Trapezoid Capitate Hamate
3
Q
How many carpal bones are there?
A
8
-total of proximal and distal rows
4
Q
How many metacarpals are there?
A
5
5
Q
How many phalanges are there
A
14
- each finger has proximal phalanx (PP), medial phalanx (MP), & distal phalanx (DP)
- EXCEPT thumb [or P1] is missing MP
6
Q
Name the 3 joints of the phalange
A
- metacarpophalangeal joint (MP)
- Proximal interphalangeal joint (PIP)
- Distal interphalangeal joint (DIP)
7
Q
Palmar aponeurosis
A
thickened area of deep fascia into which the palmaris longus attaches
8
Q
transverse carpal ligament
A
under palmarcarpal ligament [is palmar aponeurosis same thing??]
- dense, tough band of connective tissue continuous with the antebrachial fascia.
- extends from the pisiform and hamate medially to the scaphoid and trapezium laterally
- ***forming the carpal tunnel
9
Q
Dupuyten contracture
A
shortening, thickening, & fibrosis of palmar fascia 7 aponeurosis
10
Q
Which tendons & nerve(s) pass through the carpal tunnel?
A
9 tendons: - 4 from flexor digitorum superficialis -4 from flexor digitorum profundus -1 from flexor pollicus longus 1 nerve: median nerve
11
Q
how do you test for carpal tunnel syndrome?
A
Phalens manuever:
hold pt’s wrists in acute flexion (back to back like upside down prayer) for 30 -60 secs
-If numbness and tingling develop over the distribution of the median nerve (palmar surface of the thumb, and index, middle, and part of the ring fingers), the sign is positive
12
Q
Thenar muscles
A
(Thenar think thumb side) 3 muscles: -abductor pollicis brevis -opponens pollicis -flexor pollicis brevis N: recurrent branch of the median nerve
13
Q
recurrent branch of the median nerve
A
In: thenar muscles
14
Q
Hypothenar muscles
A
(pinky side) 3 muscles: Abductor digiti minimi Opponens digiti minimi Flexor digiti minimi brevis N: ulnar nerve
15
Q
dorsal branch of the ulnar nerve
A
- becomes superficial in the distal forearm
- receives cutaneous sensory information from the ulnar side of the dorsal hand and one and one-half digits.
16
Q
Deep Ulnar nerve
A
supplies motor fibers to the: hypothenar muscles lumbricals for the fourth and fifth digits all of the interossei muscles adductor pollicis muscle
17
Q
superficial ulnar nerve
A
supplies cutaneous sensory fibers to one and one-half digits
18
Q
Ulnar Canal Syndrome
A
aka Guyon tunnel syndrome
-hypoesthesia of the medial one and one-half fingers and weakness of intrinsic hand muscles
19
Q
superficial palmar arterial arch
A
-found immediately beneath the palmar aponeurosis. –major contributor to the arch is the ulnar artery
20
Q
ulnar artery
A
- passes lateral to the pisiform bone along with the ulnar nerve to enter the palm of the hand.
- gives rise to the common palmar digital arteries and then near the web of the digits gives rise to the proper palmar digital arteries that continue distally to the finger tips
21
Q
common palmar digital arteries
A
stem from superficial palmar arterial arch (ulnar artery)
- 4 of them?
- from palm to finger branching sites
22
Q
proper palmar digital arteries
A
continue distally to the finger tips (1 on either side of finger) from common palmar digital arteries
23
Q
fibrous digital sheaths
A
- hold tendons of the flexor digitorum superficialis and profundus in place over the digits
- inside fibrous sheaths are the synovial digital sheaths
24
Q
synovial digital sheaths
A
lay inside fibrous digital sheaths
25
where does tendon of flexor pollicus longus terminate?
base of DP of thumb
26
where does tendon of flexor digitorum superficialis terminate?
- go to all 4 fingers
| - split over the body of the proximal phalanx and inserts into the base of the middle phalanx.
27
Where do the tendons of flexor digitorum profundus terminate?
- goes to all 4 digits
- pass through the split in the tendons of the flexor digitorum superficialis and continue distally to insert into the base of the distal phalanx
28
Vincula
- are connective tissue bundles that extend from the tendons of the flexor digitorum muscle to the periosteum of the bone
- thought to carry a blood supply from the bone to the tendons
29
Lumbrical muscles
O: from the deep extensor tendons
I: tendons pass on the radial side of the metacarpal-phalangeal joint (MP joint) to insert into the extensor hood.
N: Lumbricals 1 and 2 are innervated by the median nerve
-lumbricals 3 and 4 are innervated by the ulnar nerve.
Fxn: The lumbricals flex the MP joint and extend the PIP and DIP joints by acting through the extensor hood
30
adductor pollicis
O: deep in the hand from 2nd & 3rd metacarpal bones and adjacent carpal bone
I: medial side of the base of the proximal phalanx of the thumb
N: deep branch of the ulnar nerve.
31
palmar interossei muscles
- found between the metacarpal bones
O: on the metacarpals
I: into the proximal phalanx and extensor hood.
Fxn: adduct the 2nd, 4th and 5th fingers towards the midline (palmar interossei adduct – PADs)
N:ulnar nerve.
32
Dorsal interossei muscles
O:on the metacarpals
I: into the proximal phalanx and extensor hood.
Fxn: abduct the 2nd, 3rd, and 4th fingers from the midline (dorsal interossei abduct – DABs).
N: ulnar nerve.
33
Deep palmar arterial arch
-continuation of the deep branch of the radial artery. Note that the radial artery has a palmar branch that is continuous with the superficial palmar artery derived mainly from the ulnar artery. The deep palmar arterial arch sends arterial branches that communicate with the common palmar digital arteries.
34
Digital branches of the Median nerve
- median nerve supplies the palm of the hand and the palmar (volar) surface of three and one-half fingers (thumb, index and middle finger, and lateral side of ring finger)
- supplies the dorsal side of the distal phalanx of these digits.
35
Digital branches of the ulnar nerve
The ulnar nerve supplies the hypothenar eminence, and the medial side of the ring finger and all of the little finger.
36
flexor tendons of the hand vs extensor tendons (origins)
flexor tendon origin: ulnar/medial side
| extensor tendon origin: radial/lateral side
37
extensor retinaculum
a thickening of the antebrachial fascia in the distal forearm that binds down the extensor tendons as they pass onto the dorsum of the hand
38
superficial branch of the radial nerve
passes from below the brachioradialis muscle and over the extensor retinaculum
-supply cutaneous innervation to the dorsum of the hand (thumb-radial half of ring finger)
39
what makes up the anatomical snuffbox?
EPL- extensor pollicis longus
EPB- extensor pollicis brevis
APL- abductor pollicis longus
***radial artery passes through here
40
Extensor pollicis longus (EPL)
O: posterior middle third of the ulna and adjacent interosseous membrane
I: distally to the base of the distal phalanx of the thumb.
N: posterior interosseous nerve
41
extensor pollicis brevis (EPB)
O: posterior distal third of the ulna and adjacent interosseous membrane
I: distally to the base of the proximal phalanx of the thumb.
N: posterior interosseous nerve
42
Abductor pollicis longus (APL)
O: proximal halves of the radius, ulna and interosseous membrane
I: distally to the base of the first metacarpal.
N: superficial radial?
43
extensor carpi radialis longus
O: lateral supracondylar ridge distal to the origin of the brachioradialis
I: distally into the 2nd metacarpal
N: PIN
44
extensor carpi radialis brevis
O: lateral epicondyle (common extensor origin)
I: distally into the 3rd metacarpal.
N: PIN
45
extensor digitorum muscle
O: common extensor area (lateral epicondyle)
I: into the extensor hood or expansion of the medial four fingers
N: PIN
FXN: primarily extends the fingers at the MP joint.
46
extensor digitorum minimi muscle (EDM)
O: from the common extensor origin
I: into the extensor expansion of the 5th finger
N: PIN
47
extensor carpi ulnaris muscle (ECU)
O: lateral epicondyle and posterior border of the ulna
I: dorsal side of the base of the 5th metacarpal
N: PIN
FXN: extends and adducts the hand.
48
extensor indicis muscle
O: distal third of the ulna and adjacent interosseous membrane
I: extensor expansion of the 2nd finger
N: PIN
49
supinator muscle
O: lateral epicondyle, posterior ulna, and adjacent ligaments associated with the radius,
I: posterior lateral and anterior surfaces of the proximal radius
N: radial?
FXN: supinates the forearm and hand.
50
what are the outcropping muscles?
Abductor pollicis longus
| Extensor pollicis brevis
51
posterior interosseous nerve
continuation of the deep branch of the radial nerve
| In: supplies all of the extensor muscles in the forearm.
52
posterior interosseous artery
enters the posterior compartment immediately below the supinator muscle.
runs w/ PIN for part of it
53
dorsal interosseous muscles
The four dorsal interossei are all abductors of the digits (DABs)
Fxn: they abduct the 2nd, 3rd and 4th digits from the midline.
--also flex the MP jt, extend PIP & DIP jts (w/ lumbricals)
I: base of the proximal phalanx and the extensor hood.
54
extensor hood/expansion
contains the tendon of the digital extensors
| -where interossei & the lumbricals insert
55
radial collateral ligament of the elbow
attaches the radius to the humerus
| -continuous with the anular ligament that encircles the head of the radius
56
anular ligament of the radius
???
57
interossoseous membrane
syndesmosis type joint that bridges the space between the radius and ulna.
(posterior interosseous artery passes between the bones superior to the membrane)
58
what nerve innervates all of the interossei muscles?
ulnar nerve
59
ulnar collateral ligament of the elbow
is located on the medial side of the elbow and attaches the ulna to the humerus.
60
ulnar & radial collateral ligaments of the wrist
join the carpal bones and the radius and ulna, respectively
| -Sprains of these ligaments are not uncommon
61
Median nerve palsy (proximal) & its Signs
- Atrophy of thenar eminence
- Thumb is laterally rotated and adducted
- Loss of thumb flexion
- Loss of flexion at 2nd and 3rd PIP joints
- Loss of flexion at 2nd and 3rd DIP joints
- Weakened flexion of 2nd and 3rd MP joints
- ***hand of benediction
62
what causes atrophy of thenar eminence?
N: recurrent branch of the median nerve
| -injury to it
63
what causes the thumb to be laterally rotated & adducted?
unopposed action of muscles supplied by the radial and ulnar nerves
64
what causes loss of thumb flexion?
loss of innervation of flexor pollicis longus
65
what causes loss of flexion at the 2nd & 3rd PIP joints?
loss of innervation of the FDS by the median nerve
66
what causes loss of flexion at the 2nd & 3rd DIP joints?
– loss of innervation of the FDP by the median nerve
67
what causes loss of flexion at 2nd & 3rd MP joints?
loss of innervation of the 1st and 2nd lumbricals by the median nerve
68
Median nerve Injury (DIstal) aka Carpal tunnel syndrome!
| Signs?
Paresthesia in the lateral three and a half fingers
No loss or abnormal sensation in the palm of the hand
Loss of coordination and strength in the thumb
Difficulty in utilizing the thumb in gripping things
Weakened flexion of 2nd and 3rd MP joints
Phalen test positive
69
why is there Paresthesia in the lateral three and a half fingers w/ carpal tunnel syndrome?
– abnormal sensations in the median nerve
70
why is there no loss or abnormal sensation in the palm w/ carpl tunnel?
area innervated by the palmar cutaneous branch of the median nerve before the median nerve passes through the carpal tunnel
71
why do carpal tunnel pt's have loss of coordination & strength in the thumb?
thenar muscles weak due to loss of innervation by median nerve (recurrent branch)
72
why is there weakened flexion of 2nd & 3rd MP joints in carpal tunnel syndrome?
loss of innervation of the 1st and 2nd lumbricales
73
What does positive Phalen test show?
compression of the median nerve in the carpal tunnel produces abnormal sensations in the lateral three and one-half digits
74
Ulnar nerve palsy
- ***CLaw hand
- Loss of flexion at the 4th and 5th DIP joints – loss of innervation of the FDP by the ulnar nerve
- Loss of flexion at 4th and 5th MP joint (hyperextension of joint) – loss of innervation of the 3rd and 4th lumbricals by the ulnar nerve
- Inability to extend the IP joints when attempting to straighten the fingers – loss of innervation of the 3rd and 4th lumbricals and interossei by the ulnar nerve
- Atrophy of the interossei muscles – loss on innervation by the ulnar nerve
- Weakness of thumb adduction – loss of innervation of the adductor pollicis by the ulnar nerve
75
ulnar canal syndrome (guyun's tunnel syndrome)
- No loss of flexion at 4th and 5th DIP joints – FDP innervation by the ulnar nerve is intact
- Loss of flexion at 4th and 5th MP joint (hyperextension of joint) – no innervation of 3rd and 4th lumbricals by the ulnar nerve
- Inability to extend the IP joints when attempting to straighten the fingers – loss of innervation of the 3rd and 4th lumbricals and interossei by the ulnar nerve
- Hypoesthesia and paresthesia in little finger and ulnar half of ring finger – loss of sensory innervation by ulnar nerve
- Atrophy of the interossei muscles – loss of innervation by ulnar nerve
- Weakness of thumb adduction – loss of innervation of adductor pollicis by ulnar nerve
76
radial nerve injury (wrist drop)
Inability to extend the wrist and fingers at MP joint – loss of innervation of extensor muscles by the radial nerve
Wrist partially flexed – loss of innervation of extensor muscles by the radial nerve
77
subluxation & dislocation of radial head
"nursemaid's elbow" or "pulled elbow"
-The head of the radius is pulled out of the anular ligament, resulting in a subluxation or dislocation of the radial head
78
Mallet Finger
-Avulsion of the extensor tendon from the distal phalanx when the extensor tendon is contracted and the distal phalanx is forcibly flexed
-phalanx is held in a flexed position because of the unopposed action of the flexor digitorum profundus
Ex: sliding into 3rd base
