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Flashcards in Hand Deck (45):
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common flexor sheath

deep to the flexor retinaculum, tendons of FDS and FDP enter the common flexor sheath
enter the central compartment of the hand and fan to enter their respective digital synovial sheaths
near base of proximal phalanx, tendon of FDS splits to surround tendon of FDP
split in FDS tendon called tendinous chiasm

1

fibrous digital sheaths

contain flexor tendons and synovial sheaths
extend from heads of metacarpals to the bases of the distal phalanges
prevent the tendons from pulling away from the digits

2

osseofibrous tunnels

formed by attachment of fibrous digitial sheaths to the bones
tendons pass through to reach the digits

3

anular and cruciform ligaments of fibrous sheath

often referred to as pulleys
thickened reinforcements of these sheaths

4

vincula

synovial folds that small blood vessels run through to flexor tendons from periosteum of phalanges

5

sesamoid bones in thumb

FPL tendon runs between
one is in combined tendon of FPB and APB and the other is in the tendon of the AD

6

what arteries provide blood to the hand

ulnar and radial and their branches

7

ulnar artery in the hand

enters the hand anterior to the flexor retinaculum between the pisiform and the hook of the hamate via the ulnar or Guyon canal
lies lateral to the ulnar nerve
gives rise to deep (palmar) branch and then continues superficial to the long flexor tendons where it is the main contributor to the superficial palmar arch

8

superficial palmar arch

gives rise to three common palmar digital arteries
that anastamose with palmar metacarpal arteries from the deep palmar arch
each common palmar digital artery divides into a pair of proper palmar digital arteries that run along adjacent sides of 2nd to 4th fingers

9

radial artery in the hand

curves dorsally around the scaphoid and trapezium in the floor of the snuff box and enters the palm by passing between the heads of the 1st dorsal interosseus muscle
then turns medially and passes between the heads of the AD
ends by anastomosing with the deep branch of the ulnar artery to form the deep palmar arch

10

deep palmar arch

formed mainly by radial artery
lies across the metacarpals just distal to their bases
gives rise to three palmar metacarpal arteries and the princeps pollicis artery

11

radialis indicis artery

passes along lateral side of index finger

12

superficial and deep palmar venous arches

associated with arterial ones
drain into deep veins of forearm
dorsal digital veins drain into three dorsal metacarpal veins which unite to form the dorsal venous network
cephalic vein originates from the lateral side of dorsal venous network, and basilic vein from the medial side

13

nerve supply of hand

median, ulnar and radial nerves

14

median nerve in the hand

enters through the carpal tunnel
then supplies two and a half thenar muscles and the 1st and 2nd lumbricals
also sends sensory fibers to the skin on the lateral palmar surface, the sides of the first three digits, the lateral half of the 4th digit and the dorsum of the distal halves of these digits

15

palmar cutaneous branch of the median nerve

supplies the central palm
arises proximal to the flexor retinaculum and passes superficial to it

16

carpal tunnel

passageway deep to the flexor retinaculum between the tubercles of the scaphoid and trapezium on the lateral side and the pisiform and hook of hamate on the medial side
contains 9 tendons: 4 from flexor digitorum superficialis, 4 from flexor digitorum profundus, 1 from flexor pollicis longus
contains median nerve

17

ulnar nerve in the hand

leaves forearm by emerging from deep to the tendon of the FCU
continues distally via the Guyon canal where it is bound by fascia to the anterior surface of the flexor retinaculum
then passes alongside lateral border of the pisiform
gives off palmar cutaneous branch just proximal to the wrist,
gives off dorsal cutaneous branch
ends at distal border of flexor retinaculum by dividing into superficial and deep branches

18

palmar cutaneous branch of ulnar nerve

that passes superficial to flexor retinaculum and palmar aponeurosis: supplies skin on medial side of palm

19

dorsal cutaneous branch of ulnar nerve

supplies medial half of dorsum of hand, 5th finger and medial half of the 4th finger

20

superficial branch of ulnar nerve

supplies cutaneous branches to the anterior surfaces of the medial one and a half fingers

21

deep branch of ulnar nerve

supplies hypothenar muscles, medial two lumbricals, AD, deep head of FPB and all the interossei
also supplies several joints (wrist, intercarpal, carpometacarpal, and intermetacarpal)

22

nerve of fine movements

ulnar nerve
because innervates muscles concerned with intricate hand movements

23

radial nerve in the hand

supplies no hand muscles
terminal branches: superficial and deep, arise in the cubital fossa

24

superficial branch of radial nerve

entirely sensory
pierces deep fascia near dorsum of the wrist to supply the skin and fascia over the lateral two thirds of the dorsum of the hand, the dorsum of the thumb, and the proximal parts of the lateral one and a half digits

25

anatomical snuff box

lateral (anterior) boundary: tendons of APL and EPB
medial (posterior) boundary: tendon of EPL
radial artery crosses floor, where can feel pulsations
scaphoid ad less distinctly, trapezium are palpable in the floor

26

flexion creases

in the palm where the skin is firmly bound to deep fascia

27

wrist creases

proximal, middle, distal
distal indicates the proximal border of the flexor retinaculum

28

palmar creases

radial longitudinal crease (life line)
proximal and distal transverse palmar creases

29

transverse digital flexion creases

proximal digital crease: at the root of the digit, approximately 2 cm distal to the metacarpophalangeal joint. of the thumb, crosses obliquely, proximal to the 1st metacarpophalangeal joint
middle digital crease:lies over proximal interphalaneal joint
distal digital crease: proximal to distal inter phalangeal joint

30

depuytren contracture of palmar fascia

disease of palmar fascia resulting in progrossive shortening, thickening and fibrosis of the palmar fascia and palmar aponeurosis
fibrous degeneration of the longitudinal digital bands of the aponeurosis on the medial side of the hand pulls the 4th and 5th fingers into partial flexion at the metacarpophalanageal and proximal interphalangeal joints
frequently bilateral
treatment of contracture usually involves surgical excision of fibrotic partsof palmar fascia to free fingers

31

tenosynovitis

inflammation of the tendon and synovial sheath
digits swells and movement becomes painful
b/c tendons of 2nd through 4th digits mostly have separate synovial sheaths, infection usually confined to infected digit
if infection untreated, proximal ends of sheaths may rupture, allowing infection to spread to midpalmar space.
infection in little finger may spread to common sheath and through carpal tunnel to forearm

32

quervain tenovaginitis stenosans

excessive friction of APL and EPB tendons in synovial sheath results in fibrous thickening of sheath and stenosis of osseofibrous tunnel
causes pain in wrist that radiates proximally to the forearm and distally to the thumb

33

digital tenovaginitis stenosans

trigger finger or snapping finger
tendons of FDS and FDP enlarge, forming a nodule proximal to the tunnel
unable to extend the finger
when finger is extended passively, snap is audible

34

carpal tunnel syndrome

results from any lesion that significantly reduces size of carpal tunnel or increases size of some of the structures of coverings that pass through it
median nerve most affected: tingling, numbness in lateral three and a half digits
also innervates 3 thenar muscles:wasting of thenar eminence and progressive loss of coordination and strength in the thumb may occur
unable to oppose thumb
carpal tunnel release: cut of flexor retinaculum toward medial sideof wrist

35

paresthesia

tingling

36

hypesthesia

diminished sensation

37

anesthesia

absence of tactile sensation

38

trauma to median nerve

occur in forearm and wrist:most common is carpal tunnel
laceration of wrist: paralysis and wasting of thenar muscles and the first two lumbrical muscles. opposition of thumb not possible, fine movements of 2nd and 3rd digits impaired. sensation lost over thumb and adjacent 2 and a half digits
median nerve injury resulting from perforating wound in elbow region: loss of flexion of proximal & distal interphalangeal joints of 2nd and 3rd digits. ability to flex these metacarpophalangeal joints also affected because 1st and 2nd lumbricals. thumb movements limited to flexion and extension of thumb in plane of palm

39

ulnar nerve injury

1 of 4 places: 1. posterior to medial epicondyle of humerus (most common). 2. in cubital tunnel formed by tendinous arch connecting humeral and ulnar heads of FCU. 3. at the wrist. 4. in the hand
at elbow, wrist or hand: extensive motor and sensory loss in the hand
in distal forearm: denervates most intrinsic hand muscles: flexion goes laterally because FCR unbalanced by FCU
claw hand: results from interosseus muscles: unopposed action of extensors and FDP

40

compression of ulnar nerve

at the wrist where it passes between pisiform and hook of hamate
depression between these bones is converted by pisohamate ligament into Guyon tunnel
ulnar canal syndrome:manifest by hypoesthesia in medial one and a half fingers and weakness of intrinsic hand muscles
clawing of 4th and 5th fingers may occur

41

radial nerve injury

in the arm by a fracture of humeral shaft can produce disability of hand
wrist drop is primary clinical manifestation
extent of anesthesia is minimal and usually confined to small area on lateral part of dorsum of hand
severance of deep branch results in inability to extend thumb and metacarpophalangeal joints of other digits. loss of sensation does not occur because deep branch is entirely muscular and articular in distribution

42

laceration of palmar arches

bleeding is usually profuse when the palmar arterial arches are lacerated
may not be sufficient to ligate only one forearm artery when arches are lacerated because vessels usually have numerous communications in the forearm and hand and bleed from both ends
bloodless surgical operating field:compress brachial artery and branches proximal to elbow

43

palmar wounds and surgical incisions

superficial palmar arch is at same level as the distal extremity of common flexor sheath
incisions or wounds along the medial surface of the thenar eminence may injure recurrent branch of the median nerve to the thenar muscles

44

ischemia of digits

intermittent biliateral attacks marked by cyanosis and often accompanied by paresthesia and pain, characteristically brought on by cold and emotional stimuli
cause is idiopathic (unknown) or primary, called Raynaud syndrome
arteries of upper limb innvervated by sympathetic nerves. postsynaptic fibers from sympathetic ganglia enter nerves that form brachial plexus and are distributed to digital arteries through branches arising from plexus
when treating ischemia resulting from Raynaud syndrome, may be necessary to perform cervicodorsal presynaptic sympathectomy to dilate digital arteries