surgical anatomy of hand and its clinical scenarios

1. Dr SD Sanyal
Lt Col R Venkatnarayan

3.  The hand is the region of the upper limb
distal to the wrist joint.
 It is subdivided into three parts:
 1. Wrist
 2.Metacarpus
 3.Digits (five fingers including the thumb).
 The hand has an anterior surface (palm) and a
dorsal surface (dorsum of hand).

5.  Palmar aponeurosis
 Blood supply
 Nerves
 Carpal tunnel
 Guyon’s canal
 Palmar spaces
 Nail anatomy

6.  The palmar aponeurosis is a triangular-
shaped condensation of deep fascia that
covers the palm and is anchored to the skin
in distal regions.
 The apex of the triangle is continuous with
the palmaris longus tendon.

8. Figure 4 Anatomy of the radial artery
Byrne, R. A. et al. (2012) Vascular access and closure in coronary angiography and percutaneous intervention
Nat. Rev. Cardiol. doi:10.1038/nrcardio.2012.160

15.  All of the intrinsic muscles of the hand are
innervated by the deep branch of the ulnar
nerve except for the three thenar and two
lateral lumbrical muscles, which are
innervated by the median nerve.

16.  The carpal tunnel is formed anteriorly at the
wrist by a deep arch formed by the carpal
bones and the flexor retinaculum.

17.  Four tendons of the
flexor digitorum
profundus
 Four tendons of the
flexor digitorum
superficialis
 One tendon of the
flexor pollicis longus
 Median nerve

20.  1. Hypothenar
compartment
 2. Thenar compartment
 3. Central compartment
 4. Adductor
compartment
 5.Interosseous
compartment

21.  THENAR
 Abductor Pollicis Brevis
 Flexor Pollicis Brevis
 Opponens Pollicis
 HYPOTHENAR
 Abductor Digiti Minimi
 Flexor Digiti Minimi
 Opponens Digiti Minimi

22.  INTERMEDIATE
 Flexor tendons covered by Synovial
sheaths
 lumbricals
 Palmar arterial arches
 Branches of Median and Ulnar nerves
 ADDUCTOR
 Adductor Pollicis

23.  No well defined spaces inside the fascial
compartments
 Become apparent when there is collection
of pus
 Mid palmar septum/Intermediate palmar
septum divide intermediate comp into
Thenar & Mid palmar spaces

24. 

25.  MidPalmar space
 Thenar space
 Hypothenar space
 Radial Bursa
 Ulnar bursa

26.  Anterior – Palmar aponeurosis,
superficial palmar arch,
flexor tendons of medial 3 digits covered
in ulnar bursa and medial 3 lumbricals
 Posterior - Fascia covering 3rd & 4th
interossei and metacarpal bones
 Medial – Medial Palmar septum
 Lateral - Midpalmar septum
 Proximal – distal margin of flexor
retinaculum
 Distal - medial 2 web spaces thru
lumbrical canals

27.  Anterior - Palmar aponeurosis,
superficial palmar arch,
flexor tendon of index finger covered
with synovial sheath, tendon of FPL
 Posterior – fascia covering adductor
pollicis
 Lateral - Lateral palmar septum
 Medial MidPalmar septum.
 Proximal – distal margin of flexor
retinaculum
 Distal - 1st web space thru lumbrical
canal

28.  Posterior – 5th Metacarpal
 Lateral – Hypothenar septum
 Medial & Ant– Hypothenar Muscles

29. 

30.  Synovial sheath surrounding
Flexor Pollicis Longus tendon
 Extends from forearm( 2 cm prox to Flexor
retinaculum) to base of terminal phalanx of
thumb

31.  Common synovial sheath surrounding
tendons of Flexor digitorum superficialis
and profundus
 Extends from forearm( 2 cm prox to Flexor
retinaculum) to mid palm level where it
ends as cul-de-sac .
 Continuous with digital sheath around
flexor tendons of little finger

32.  4 Subcutaneous spaces
 From its free margin – extends to level of
MCP joint.
 CONTENTS - S/C fat
Superficial transverse metacarpal ligament,
interosseous and lumbrical tendons,
digital nerves and vessels.

34. A. Nail plate
B. Lunula
C. Root
D. Sinus
E. Matrix
F. Nail bed
G. Hyponychium
H. Free edge

37. Infection of the soft tissues surrounding the
fingernail and is the most common infection
of hand.

40.  Cause:
◦ Inocculation of bacteria as a consequence of minor
trauma such as
 Nail bitiing
 Poor manicuring
 Small puncutre wounds.
 Staph aureus is most common pathogen but
anaerobes may also be involved.

41.  UNCOMPLICATED INFECTION:
◦ Oral antiboitics / Rest / Heat / Elevation
 INFECTION WITH ABSCESS:
◦ Localized to one nail fold;
 Elevation of fold bluntly with a haemostat
 Using no 11 blade directing away from nail bed
through the insensate epithelium where abcess is
pointing.

42. ◦ Eponychia (involving proximal nail & one lateral
fold;
 Elevating the eponychial fold and removal of loose
portion of nail plate to drain abscess and allow for
secondary healing.

43.  A felon is an abscess of the distal pulp of
the thumb or finger.

45.  Pulp Anatomy:
◦ 15-20 longitudonal septa anchoring skin to distal
phalanx dividing the pulp into multiple closed
compartments.

46.  Pathophysiology:
◦ Abscess formation within these small compartments
results in rapid development of swelling and throbbing
pain, worsened by dependency.
 Complications:
◦ Necrosis of entire pulp
◦ Extension of infection into;
 Flexor tendon sheath
 Distal IP joint
 Distal phalanx.

47.  Causes:
◦ Mostly Puncture wound with foreign body, so
radiographs are mandatory.
 Pathogen:
◦ Staph aureus but gram –ve infection can also occur esp
in immunocompromised patients.
 Conservative Management: For early Felons…
◦ Oral antiboitics
◦ Rest
◦ Warm Soaks
◦ Elevation.

48.  Herpex simplex virus infection can be:
◦ Primary
◦ Recurrent
 Population at risk:
◦ Children, adolesents with genital herpes infection
◦ Health care workers with frequent exposure to oral
secretions.
 Must be distinguished from Paronychia and Felon
because incision and drainage is generally
contraindiacted.

50.  Pathophysiology:
◦ A prodromal phase of 24-72 hours of burning pain
prior to the development of skin changes.
◦ Erythema and swelling
◦ Formation of clear vesicles which sometimes
coalesce around nail fold.
◦ Fluid may become turbid but not frankly purulent
unless bacterial superinfection occurs.
◦ Pulp of affected digit is not tense as in felon.

52.  Disease Course:
◦ The process occurs over approx 2 weeks and resolves
over next 7-10 days.
 Diagnosis:
◦ Viral culture
◦ Tzanck smear
 Treatment: Generally conservative
◦ Rest & Elevation
◦ Anti inflammatory agents
◦ Acyclovir in immunocompromised states.
 Reccurence rates are around 20%.

53.  Thenar space
 Midpalmer space (subtendinous space)
 Hypothenar space
 Dorsal subapeneurotic space
 Web spaces.
◦ Thenar and midpalmer spaces are clinically more
important.

54. MIDPALMER SPACE
INFECTION
THENAR SPACE
INFECTION

55.  A penetrating injury usually a splinter is the
most common cause.
 Staph aureus is the usual pathogen.
 Antiboitics / Rest / Heat / Elevation for early
infections but most cases need Surgical
Drainage.
 Key to success is adequate drainage while
avoiding iatrogenic injury and subsequent
scar contracutres.

56.  Curved longitudonal incision in the palm.
 Take care to avoid injury to superficial palmer
arch and digital vessels.
 Wound packed open with daily dressing
changes. OR
 Irrigation catheter in proximal wound and a
penrose drain in distal wound for continous
or intermittent irrigation.

57.  Combined dorsal and volar incisions.
 Take care to avoid injury to palmer cutaneous
branch of median nerve in proximal end of
incision
 And avoiding injury to motor branch of median
nerve.
 Post op care include
◦ Splinting
◦ Dressing changes
◦ Catheter irrigation.

59.  Most serious hand infection.
 If left untreated;
◦ Destruction of gliding
surfaces in sheath
◦ Necrosis of tendons
◦ Osteomyelitis
◦ Amputation.
 Ring, middle and index fingers mostly involved
 Staph aureus usual pathogen with few cases due to
haematogeneous spread of gonococcal infection.

61.  KANAVEL cardinal sign of flexor
tenosynovitis:
1. Fusiform swelling of finger
2. Paritally flexed posture of digit
3. Tenderness over entire flexor sheath
4. Dipropotionate pain on
passive extension.

63.  IV antiboitcs is the most common
justification for hospitalization.
 Continuous or intermittent wound irrigation.
 Frequent dressing changes.
 Three phases of treatment in cases of severe
infections where extensive debridement and
complex reconstructions are needed.

64.  Phase 1> Rapid infection control and staged
debridement.
◦ A second look surgery done in 24-48 hours.
 Phase 2> Salvage of vital structures and soft
tissue coverage.
◦ With identification of structures that will later
require reconstruction.
 Phase 3 > Reconstructive Surgery.
◦ Once stable soft tissue coverage is achieved.

65. 1. Incisions should never cross a flexion crease
at a right angle
2. Avoid iatrogenic injury to critical structures
1. Tendons
2. Neurovascular bundles
3. Incision lengthening is usually needed and
should be planned by making potential
extensions with a pen.

66. 4. Torniquet Control is helpful as infective
process can lead to profuse bleeding.
o Finger Torniquet
o Penrose drain
o Glove technique
o Standard Pnematic Torniquet with exanguination
o Esmarch bandage
o Elevation of limb with digital pressure on brachial
artery.

67. a. REST (IMMOBILIZATION)
o Limits opening of tissue plans restricting the
spread of infection.
o Should be done in a functional position.

68. b. HEAT (WARM MOIST SOAKS):
o Maximum vasodilatory effect reached in 10 min.
o Frequent soaks preferred over continuous soaks.
o Severe Infections:
o Moist hot towels with plastic barrier and a dry towel
as insulator.

69. c. ELEVATION:
o Reduces edema by improving venous/lymphatic
drainage.
o Limb should be above level of heart for
dependant drainage.
o Limb placed over chest or on a pillow while
sitting.

70.  Metacarpalphalan
geal joints in 60
to 70 degrees of
flexion
 PIP and DIP joints
extended

72. Location of Incisions:
Index, middle & ring: ULNAR SIDE
Thumb & small: RADIAL SIDE

74.  Eponychia:
 Elevate eponychial fold and excise prox 1/3 of nail
 Lateral (paronychial) incisions may aid in separating the nail
base if not already separated

75.  2 basic approaches:
 Open vs. Closed
 Open drainage:
 Decompression of the entire tendon
sheath via mid-axial & palmar incisions
 Wounds are left open to drain & heal
secondarily
 Rehab is prolonged; permanent finger
stiffness not infrequent
 Most useful for advanced cases where
resection of necrotic tendon is required

76.  These incisions:
 ensure adequate drainage
 heal quickly
 Do not interfere with rehab
 After removal of catheter and
drains begin gentle passive &
active ROM

78.  Drain via volar or dorsal incisions
in the 1st web space or both:
 Identify neurovascular structures
 unroof the adductor fascia to open
the abscess cavity
 irrigate & debride
 catheter in volar incision & close;
penrose in dorsal incision & close
 compressive dressing & plaster splint

79.  Drain via wide palmar incisions
with +/- resection of palmar fascia
to ensure drainage of abscess cavity.
 or may place irrigation catheter &
drain and close primarily.

80.  Closed irrigation using 2 incisions, a catheter & a
drain as previously outlined.