palmar aponeurosis & muscles.pptx

muscles of hand

1. Hand

2. Hand Composed of Bones Muscles Ligaments To allow a large amount of movements

3. Hand Has 2 surfaces Palmar Dorsal

4. Palm – Features Hollow Eminence Creases

5. Palm – Features Palmar surface Thick skin Devoid of Hairs & sebaceous glands Connected with deep fascia by Many fibrous septa Helps grip by restricting mobility of skin Has fat Act as cushion To withstand pressure

6. Palm - features Has Creases or lines 3 types Flexure lines Papillary ridges Langer lines

7. Creases - Flexure lines Visible marking Lies close to joints On medial 4 fingers 2 interphalangeal creases Proximal crease only marks joint Crease between palm & fingers Do not represent the metacarpo -phalangeal joint Joint lies 2 cm proximal to crease Distal skin crease of wrist Represents proximal border of flexor retinaculum At the midpoint Median nerve passes behind

8. Creases - Flexure lines Wrist Proximal Distal Palm Longitudinal Mid-palmar Radial Transverse Proximal Longitudinal Applied anatomy – Simian’s crease Phalanges Proximal Middle Distal

9. Creases – Papillary ridges Otherwise - Finger prints Peculiar over the flexor surface of distal phalanges Corresponds to Pattern of underlying dermal papilla Ducts of sweat gland opens 3 types Whorl, loop & arch Helps in personal identity Dermatoglyphics Science of finger prints

10. Creases – Langer lines Produced by Bundles of collagen fibres of dermis On dorsum Transverse On palm Longitudinal

11. Hand - Dorsum Dorsal surface Thin skin Presence of Hair & sebaceous & sweat glands Beneath skin Dorsal digital nerves Dorsal venous plexus Drains not only Dorsal surface but also palm To avoid the pressure of grip

12. Superficial fascia Subcutaneous tissue Contains Fat Palmaris brevis Lies across the base of hypothenar eminence Superficial transverse ligament of palm Across roots of medial 4 fingers

13. Palmaris brevis Lies across the base of hypothenar eminence Origin Flexor retinaculum & central part of palmar aponeurosis Insertion Dermis of ulnar border of hand Nerve supply Superficial branch of ulnar nerve Action Improves the grip Morphology Remnant of Panniculus carnosus

14. Superficial transverse ligament of Palm Modification of superficial fascia Stretches across Free margin of the webs of medial four fingers Structures passing deep to it Digital vessels & nerves

15. Cutaneous nerves Palmar cutaneous branch of median – in lower part of forearm – passes into hand above flexor retinaculum – supplying skin over thenar eminence & middle of palm Palmar cutaneous of ulnar – near lower forearm –supplies skin of medial 1/3 of palm

16. Deep fascia Thickened at 3 sites Flexor retinaculum Palmar aponeurosis Fibrous flexor sheath

17. Palmar aponeurosis Triangular in shape Occupies the central area of the palm Has Apex Base Apex Blends with distal border of flexor retinaculum Continuous with palmaris longus tendon Base Lies at bases of medial four fingers Divides into four digital slips Further each digital slip divided into Superficial & deep sets of fibres

18. Palmar aponeurosis – superficial & deep fibres Superficial fibres Joins with dermis Blend with superficial transverse ligament of palm Deep fibres Divides into 2 bands Attaches to Deep transverse ligament of palm Palmar ligament of metacarpophalangeal joint Bases of proximal phalanges Fibrous flexor sheaths

19. Palmar aponeurosis – space between the slips Intervals between the four digital slips Connected by transverse fibres Structures passing Digital vessels Digital nerves Lumbricals

20. Palmar aponeurosis – medial & lateral palmar septa Medial septum From medial margin To palmar surface of shaft of 5 th metacarpal Lateral septum From lateral margin To 1 st metacarpal bone Septa subdivide the palm into fascial spaces

21. Palmar aponeurosis – functions Powerful grip By firm attachment of overlying skin Prevents bow-stringing Of flexor tendons Protects Vessels & nerves Provides Origin to palmaris brevis Potential spaces Septa from aponeurosis forms Peculiarity from plantar aponeurosis Absence of digital slip to thumb Allows free movement of thumb Plantar aponeurosis Has 5 slips Morphology Degenerated part of palmaris longus tendon

22. Palmar aponeurosis Thickened deep fascia of the hand Triangular in shape Occupies the central area of the palm The apex is attached to the distal border of flexor retinaculum and receives the insertion of palmaris longus tendon. Base divides at the bases of the fingers into four slips that pass into the fingers Functions Gives firm attachment to the overlying skin and improves the grip. Protects the underlying tendons, vessels & nerves

23. Palmar aponeurosis (Central part) Thickened deep fascia of the hand Triangular in shape Occupies the central area of the palm Apex is attached to the distal border of flexor retinaculum and receives the insertion of palmaris longus tendon. Base divides at the bases of the fingers into four slips that pass into the fingers Functions: Gives firm attachment to the overlying skin and improves the grip. Protects the underlying tendons, vessels & nerves

24. Dupuytren’s contracture Hypertrophy of palmar aponeurosis –progressive fibrosis (ulnar side) Shortening & thickening of fibrous bands from aponeurosis to little and ring fingers

25. Intrinsic muscles of hand

26. Intrinsic muscles Thenar Hypothenar Lumbricals Interossei muscles

27. Intrinsic Muscles Situated totally within the hand Divided into 4 groups:- Lateral group Four thenar muscles Medial group Three hypothenar muscles Palmaris brevis Central group: Four lumbricals Four palmar interossei Four dorsal interossei All muscles are supplied by C 8 & T 1 spinal segments Through median & ulnar nerves

28. Lumbricals Earth worm 4 lumbricals Numbered from lateral to medial Arise from 4 tendons of FDP Inserted into extensor expansion Numbered from lateral to medial First & second are Unipennate Supplied by Median nerve Third & fourth are Bipennate Supplied by deep branch of ulnar Left Hand

29. Lumbricals - origin I lumbrical From radial side of tendon for index finger II lumbrical From radial side of tendon of middle finger III lumbrical From adjacent sides of the tendons for middle & ring fingers IV lumbrical From adjacent sides of the tendons for ring & little fingers Right Hand

30. Lumbricals Insertion All lumbricals pass backwards on radial side of 2 nd , 3 rd , 4 th & 5 th metacarpo -phalangeal joints respectively Insert on lateral angle of extensor expansion Action Flex the metacarpo -phalangeal joints Extend the interphalangeal joints

31. Thenar muscles Abductor pollicis brevis Flexor pollicis brevis Opponens pollicis Adductor pollicis

32. Abductor pollicis brevis Origin Tubercle of Scaphoid Crest of Trapezium Flexor retinaculum Insertion Lateral aspect of proximal phalanx of thumb Near base Action Abduction & medial rotation At Metacarpophalangeal joint Carpometacarpal joint Right angle to the thumb Nerve supply Recurrent branch of Median (C 8 & T1 )

33. Flexor pollicis brevis Origin Superficial head Crest of Trapezium Flexor retinaculum Deep head Trapezoid Capitate Insertion Lateral aspect of proximal phalanx of thumb Near base Action Flexion of carpometacarpal & metacarpophalangeal joints Nerve supply Recurrent branch of Median (C 8 & T1 )

34. Opponens pollicis Origin Tubercle of trapezium Flexor retinaculum Insertion I metacarpal Lateral margin & lateral palmar aspect Action Opposition At carpo metacarpal joint Rotating & flexing the metacarpal on trapezium

35. Thenar eminence Raised region between wrist & base of thumb Muscles Abductor pollicis brevis(median) Opponens pollicis (median) Flexor pollicis brevis(median & ulnar) Adductor pollicis (ulnar) Carpal tunnel syndrome

36. Adductor pollicis Origin Oblique head – capitate, trapezoid & bases of 2 nd & 3 rd metacarpal bones Transverse head – distal 2/3 rd of shaft of 3 rd metacarpal bone Insertion Ulnar side of base of proximal phalanx of thumb Action Transverse head – adductor &flexor of thumb Nerve supply – Ulnar nerve (deep) C8 &T1

37. Interossei Deepest structure of hand Between the metacarpal bones 8 muscles present Arranged in 2 groups Palmar interossei (4) Dorsal interossei (4)

38. Palmar interossei Superficial than dorsal interossei Smaller ones Unipennate Adduct the fingers towards middle finger No adductors for middle finger Origin 1 s t & 2nd Medial side of shafts of 1 st & 2 nd metacarpals 3 rd & 4 th From radial side of shafts of 4 th & 5 th metacarpals Insertion Base of proximal phalanx of corresponding digit on side of their origin Dorsal digital expansion 2 3 4

39. Dorsal interossei Deepest structure Fill up intermetacarpal spaces Bipennate Abductors Little & thumb have their own abductors Middle finger require abduction on both sides

40. Dorsal interossei Fills up all (4) intermetacarpal spaces Origin Contiguous sides of shafts of metacarpals Leaves a gap in between their origin Space between first dorsal interossei transmits Radial artery Gap between 2 nd 3 rd & 4 th dorsal interossei transmits Proximal perforating arteries

41. Dorsal interossei Insertion Proximal phalanges of 2 nd , 3 rd & 4 th Middle finger gets insertion on both sides 1 st & 2 nd Radial side of bases of proximal phalanges of index & middle 3 rd & 4 th Ulnar side of bases of proximal phalanges of middle & ring fingers Nerve supply Deep branch of ulnar

42. Lateral & medial angles of dorsal digital expansion of Index, middle & ring fingers receives Interossei

43. Hypothenar muscles Abductor digiti minimi Flexor digiti minimi Opponens digiti minimi

44. Abductor digiti minimi Origin Pisiform, tendon of flexor carpi ulnaris Insertion Ulnar side of base of proximal phalanx Action Abductor of little finger Nerve supply Ulnar (deep) C8 & T1

45. Flexor digiti minimi brevis Origin Hook of hamate Flexor retinaculum Insertion Ulnar side of base of proximal phalanx of little finger Action Flexor of proximal phalanx of little finger Nerve supply Ulnar (deep) C8 & T1

46. Opponens digiti minimi Origin Hook of hamate Flexor retinaculum Insertion Ulnar border of 5 th metacarpal Action Flexes 5 th metacarpal Nerve supply Ulnar (deep) C8 & T1

47. Deep branch of ulnar nerve Course Passes between abductor digiti minimi & flexor digiti minimi Accompanied by deep branch of ulnar artery Perforates opponens digiti minimi Follow deep palmar arch

48. Branches Muscular Abductor digiti minimi Flexor digiti minimi brevis Opponens digiti minimi 3 rd & 4 th lumbricals Adductor pollicis Flexor pollicis brevis Interossei Articula r Intercarpal , carpometacarpal joints Blood vessels – ulnar & palmar arteries

49. Median nerve contd… Muscular branches to Thenar muscles Abductor pollicis brevis Flexor pollicis brevis Opponens pollicis Branches from digital nerves supply 1 st & 2 nd lumbricals