1. ANATOMY OF THE HAND BY
Dr. J . M . Hassanain

2. Hand function is an important feature in humans over other primates who lack fine control and precision

3. EMBRYOLOGY OF THE UPPER LIMB
Limb buds first appear as small elevations on ventro lateral body end of fourth week.

4. Each limb bud :
Mesenchyme derived from somatic mesoderm which is covered by a layer of ectoderm

5. Distal end of bud form flipper like limbs.
Later bones develop and myoblast aggregate to develop muscle mass .

6. Upper limb rotates laterally 90 degrees
Specific dermatone ( which is skin area supplied by a single spinal nerve )

7. ANATOMY
Bony skeleton
Muscles and soft tissues
Vessels and nerves

8. BONY SKELETON
Wrist joint composed of multiple carpal bone articulating with the radius proximally and five metacarpals distally

9. Proximal row of carpal bone. (radial to ulnar)
Proximal row of carpal bone (radial to ulnar) scafoid , lunate , traquetral , pisiform
Distal row trapezium , trapazoid , capitate , hamate

10. BONES OF THE HAND
5 Metacarpals
Thumb is no. 1
Little finger is no. 5

11. PHALANGES All fingers have 3 phalanges proximal middle distal
Except thumb has proximal distal

12. Most of tendon in the hand originate in muscles arising from the forearm
Flexor on volar aspect of forearm must arise from common flexor tendor (medial epicondyle )

13. Extensors on dorsal aspect of the forearm arise from common extensor tender on lateral epicondyl

14. In the hand ulnar side hypo thenar muscles acting on the little fingers:
Abductor digitiminimi
Flexor digitiminimi brevis
Opponens digitiminimi

15. Radial side thenar muscle acting on the thumb
Flexor, adductor pollices
Abductor pollices brevis
Opponen pollices brevis

16. Long flexors fl. digitorum superficialus fl. digitorum profundus
Act on all the fingers

17. Intrinsic
Lumbrical
Dorsal
Ventral interrosies

18. Vascular Supply of Hand
Radial artery :
Superficial palmer branch superficial palmer arch ,which arises above the wrist
Common palmer digital
Deep palmer branches
Deep palmer arch  palmer metacarpal arteries which joins the common digital
Ulnar artery  superficial palmer branch joins on side of pisiform of superficial palmer branch
Plate 439B /439A

19. VENOUS DRAINAGE OF HAND
Via : Dorsal digital vein  dorsal venous arch
Basillic vein in front of forearm

20. Peripheral nerve entrapment
There is a disproportion between volume of the peripheral nerve and space within the extremity through which it passes

21. Applied Anatomy of Ulnar Nerve
Arises directly from the medial cord of brachial plexus (C8-T1)
Lies between axillary artery laterally and axillary vein medially

22. At inferior border of subscapularis muscle nerve receives fiber of C7 ( lat. root of ulnar nerve )
Descend in arm post. to pectoralis major muscle ( posterio medial to brachial artery)

23. 8 cm above medial epicondyl with branch of superior ulnar collateral artery diverge medially from brachial artery to pierce medial intramuscular septum

24. Together descend on medial head of triceps
Nerve passes in ulner groove dorsal aspect of medial epicondyl
It innervates fl. carpi ulnaris cm above medial epicondyl

25. Potential points of compression in the arm
Ulnar nerve fibers ( medial cord ) st rib as nerve passes between rib & clavicle
8 cm proximal to medial condyl as nerve pierce intramuscular septum ( arcade of Struther )
Hypertrophy of medial head of triceps may force nerve anteriorly, as triceps contract, nerve get compressed

26. Ulnar Nerve at Elbow &Forearm
In cubital fossa ulnar nerve passes through fibro-osseous tunnel
As it leaves the canal it lies between the flexor corpi ulnanis and flexor digitorum profundus till middle of forearm

27. In distal 1/3 lies just radial to the flexor corpi ulnaris
Straight line drawn from medial epicondyl to radial margin of pisiform marks the line of the nerve

28. Supply of ulnar nerve in forearm
Muscular branch to fl. Digitorum profundus ( i.e. ulner ½ ) 3 cm distal to medial epicondyl
Palmer cutanous branch
Dorsal cutanous branch

29. Ulnar nerve enters hand
From under fl corpi ulnaris muscle , nerve and artery
Radial to pisiform , superficial to transverse carpel lig. and dorsal to superficial palmer lig.
Ulnar nerve divide to : deep terminal branch superficial palmer branch

30. Muscle supplied by ulnar nerve
Flexor corpi ulnaris
Flexor digitorum profundus ( medial 2 tendons )
Flexor digiti minimi
2 ,3 ,4th web space interossei
3rd & 4th lumbricle
Adductor pollicis
1st dorsal interosseous

31. Sensory Supply of Ulnar Nerve
Dorsal cutanous branch of ulnar : skin dorsoulnar side of hand , little finger and ulnar ½ of index finger
Medial cutanous nerve of forearm : C8-T1 skin over biceps elbow crease middle 1/3 of arm palmer skin down to forearm

32. Anatomical Sites of Compression
Points in elbow and forearm
Anconeus epitrochlearis muscle
Fibrous arcade between 2 heads of fl. carpi ulnaris
Gelberman 416, 417 ,421,422 fig 29.2,29.3 ,29.4,29.5

33. Site of compression in hand &wrist
Palmaris brevus muscle
Fibrous origin of fl digitiminmi
Ulnar artery aneurysm or thrombosis
Distal ulnar tunnel ganglia

34. MEDIAN NERVE Arises from lateral & medial cords of brachial plexus
Contain fibers C5 –T1
Forms antrolat to 3rd portion of axillary artery in upper 1/3 of arm

35. In the arm it descends post
In the arm it descends post. to pectoralis major muscle, lateral to brachial artery, antromedial to brachialis muscle, posteromedial to biceps
In mid portion of arm, median nerve crosses ant to brachial artery to lie on its medial side to enter the cubital fosse

36. The nerve enters forearm between humeral and ulnar head of pronater teres
Then runs between fl digitorum superficialis and fl digitorum profundus, later emerges 5 cm above wrist radial to tendon of palmaris longus

37. MEDIAN NERVE IN THE WRIST
It enters the wrist dorsal to transverse carpal lig through the carpal tunnel

38. Boundaries Of Carpal Tunnel
Dorsally: radio carpal lig.
Radially: scaphoid & trapezium
Palmorly: transverse carpal lig.
Ulnary: hood of hamate & pisiform

39. After exiting carpal tunnel
Median nerve splits to two parts
Common digital nerve to thumb
Proper digital nerve to radial side of index
Ulnar division of median nerve; common digital to 2nd & 3rd web

40. Muscle supplied by median nerve
Forearm
Pronator teres
Flexor digitorum superficialis
Flexor carpi radialis
Palmaris longus
Flexor digitorum profundus
Flexor pollicis longus
Pronator quadratus

41. HAND Flexor pollicis brevis Abductor pollicis brevis Opponens pollicis
First lumbrtical
Second lumbrical

42. Anatomical compression points of the median nerve
ARM:
Pectoralis minor muscle
Anomalous axillary arch muscles
Anomalous vascular arches in the axilla
Deltopectoral fascia
Supracondyloid process
Ligament of Struthers

43. FOREARM Lacertus fibrosus Pronator teres muscle
Flexor digitorum superficialis arch
Anomalous muscles
Ulnar collateral or radial artery branches

44. HAND / WRIST Carpal tunnel
Palmar cutaneous branch within the transverse retinacular ligament

45. RADIAL NERVE
Arises from the post cords of the brachial plexus behind 3rd part of axillary artery
Neural element of C5 – C8
Proximal 1/3 of arm nerve descends behind brachial artery ant to subscapularis ,teres major ,latissmus dorsi muscle and long head of triceps

46. At junction of upper and middle 1/3 of arm deviates dorsolaterally between medial and long head of triceps lying adjacent to spiral groove of humerus

47. 10 cm above lat humeral epicondyl lying between the brachialis and brachioradialis then lies between brachialis and extensor carpi radialis ant to tip of lat epicondyl dividing into : Superficial Deep branches

48. Radial Nerve In Forearm
Superficial branch ant to supinator muscle proximal 1/3 then deep to brachioradialis
The sup branch pierces the fascia on the brachioradialis on the ulnar side of tendons 7cm above wrist
On the dorsoradial side of wrist it divides into 5 dorsal digital nerves and only one branch to extensor carpi radilalis brevus muscle

49. Post interosseous nerve (deep terminal branch of radial nerve ) innervates extensor muscle of wrist
It is seperated from the radium by deep head of supinator
After leaving the supinator it lies between the abductor pollies and other extensors of forearm

50. In distal forearm it penetrates the extensor pollies brevus to lie in the interosseous membrane
Distally it divides to give sensory innervation to the wrist

51. Muscles supplied by radial nerve
Triceps : long head medial head lateral head
Anconeus
Brachioradialis
Extensor carpi longus
Extensor carpi radialis brevis

52. Muscles supplied by radial nerve
Extensor carpi ulnaris
Extensor digitorum communis
Extensor digiti minimi
Abductor pollicis longus
Extensor pollicis longus
Extensor pollicis brevis
Extensor indicis proprius

53. Anatomical compression points of the radial nerve
ARM:
Accessory subscapularis teres latissimus
Lateral head of the triceps muscle
Lateral intermuscular septum

54. FOREARM:
Posterior interosseous nerve within radial tunnel
Fibrous bands attached to radiocapitelar joint
Extensor carpi radialis brevis muscle
Arcade of Frohse
Fibrous bands within the supinator muscle

55. Superficial radial nerve
Between brachioradialis muscle & radial shaft
Between brachioradialis and extensor carpi radialis longus tendons

56. THANK YOU
THE END