The document provides an overview of various hand infections, focusing on their anatomical basis, clinical significance, and treatment options. It covers conditions such as paronychia, felon, herpetic whitlow, and space infections like midpalmar and thenar space infections, detailing their presentation, pathophysiology, and management strategies. Surgical approaches for drainage and decompression are also highlighted, emphasizing the importance of early treatment to prevent complications.

1. Hand Infections

3. Palmer Fascia
• Thick centrally  Fibrous palmer aponeurosis
– Triangular
– Proximally continous with flexor retinaculum and
tendon of palmaris longus muscle.
– Distally forms 4 digital bands attached to bases of
proximal phalanges
• Thin over the thenar and Hypothenar
Eminences

5. Fibrous digital sheaths
• Ligamentous tubes that enclose
– Synovial sheaths
– Superficial and deep flexor tendons
– Tendons of Flexor policis longus

6. Medial fibrous septum
• Medial border of palmer aponeurosis to 5th
metacarpel.
– Medial to this is hypothenar compartment
Lateral Fibrous septum
• Lateral border of palmer aponeurosis to
the 3rd metacarpel .
• Lateral to this is thenar compartment

7. Central compartment
• Between thenar and hypothenar
compartment
• Contains
– Flexor tendons and their sheaths
– Lumbricals
– Superficial palmer arterial arch
– Digital vessels and nerves

8. Adductor compartment
• Deepest muscular plane of palm
• Contains adductor pollicis

9. Radial bursa
• The radial bursa is a continuation of the flexor
pollicis longus tendon sheath through the
flexor retinaculum to a level 2.5 cm above the
wrist joint
– Superiorly continous with common sheath
– Inferiorly extends upto distal phalanx of thumb.

10. Ulnar bursa
• Ulnar bursae includes little finger tendon sheath
which begins at terminal phalanx and extends
proximally half way up the palm.
• The long flexor tendons of the fingers (FDS and
FDP) are enclosed in a common sheath while
passing through the flexor retinaculum
• These two sheath extend above the flexor
retinaculum and communicate with each other in
carpel tunnel in 80 percent of cases.

12. Superficial pulp space
• The pulp space of the fingers is a closed compartment
situated in front of the terminal phalanx of each finger
• Each space is subdivided into numerous smaller
compartments by fibrous septa
• Infection of such a space is common and serious
• Commonly occurring in the thumb and index finger
• Bacteria are usually introduced into the space by
pinpricks or sewing needles

14. Clinical significance
• Accumulation of inflammatory exudate within
these compartment causes the pressure in the
pulp space to quickly rise.
• In children, pressure on the blood vessels could
result in necrosis of diaphysis
• Close relationship of the proximal end of the pulp
space to the digital synovial sheath accounts for
the involvement of the sheath in the infectious
process when the pulp-space infection has been
neglected

17. Paronychia

18. Paronychia
• Infection of the lateral nail fold
• If Infection extends to the eponychium
(defined as the thin membrane
distal to the nail wall at the base
of the nail), it is properly termed
an eponychia.
• When infection involves both lateral nail folds
and eponychium, it is called a run-around
infection

19. • In adults, Staphylococcus aureus is the most
common pathogen
• Pathophysiology
• Infection occurs when there is violation of the
seal between the nail plate and nail fold, allowing
the inoculation of bacteria.
• Risk Factors
– Hangnails,
– Manicures,
– Penetrating trauma,
– Constant exposure to a wet or moist environment,
– Nail biting or sucking

20. • Clinical presentation
• Initial swelling, erythema, tenderness with
progression to fluctuance, and abscess
formation are typical.
• Spontaneous decompression can occur,
including tracking beneath the nail plate
(subungual abscess).
• Deeper infections can involve the nailbed,
pulp space, and bone, producing nailbed
destruction, felon, or osteomyelitis

21. Treatment
• Early stage
– Oral antibiotics,
– Warm soaks
– Rest and observation
• Surgical decompression is the treatment of choice
– Decompression is performed by carefully entering the
abscess cavity between the nail plate and nail fold with a
scalpel blade .
– A small wick is placed for 24 to 48 hours to prevent the
incision from closing and recurrence of the infection. The
wick is removed, and saline warm soaks are begun

22. A: An infected lateral and proximal nail fold can be elevated by an elevator or scalpel. B:
For extensive infections, a relief incision(s) is made perpendicular to the edge of the nail
fold to allow for removal of a portion or all of the nail plate. (Reprinted from Seiler JG.
Essentials of hand surgery. Philadelphia: Lippincott Williams & Wilkins, 2002, with
permission. Copyright American Society of Surgery of the Hand.)

23. • Depending on the extent of the infection, a partial or
complete nail plate removal with or without lateral nail
fold relief incision(s)
is performed.
• The incision should be made perpendicular to the edge
of the nail fold.
• A single or double incision is used depending on the
location of the infection
• Subungual abscesses are treated with removal of a
portion of or the entire nail. The abscess is carefully
debrided while protecting the sterile and germinal
matrices

24. (A) Elevation of the eponychial fold with flat probe to expose the base of
the nail. (B) Placement of an incision to drain the paronychium and to
elevate the eponychial fold for excision of the proximal one-third of the
nail. (C-E) Incisions and procedure for elevating the entire eponychial
fold with excision of the proximal one-third of the nail. A gauze pack
prevents premature closure of the cavity.

25. • Chronic paronychia
• Chronic paronychia occurs more commonly in individuals
constantly exposed to moist environments.
• Infections may be intermittent; clinically, the eponichial fold is
thickened and painful
• Candida albicans is a frequent offending
organism
• Topical antifungal ointments are generally used
4 to 6 weeks.
FIGURE 5. Eponychial marsupialization is performed by removing a small, crescent -
shaped portion of the eponychial fold proximal to the distal edge of the eponychial fold.
Care is taken to not injure the underlying germinal matrix. (Reprinted from Seiler JG.
Essentials of hand surgery. Philadelphia: Lippincott Williams & Wilkins, 2002, with
permission. Copyright American Society of Surgery of the Hand.)

27. Felon

28. Felon
• A felon is a deep space infection or abscess of the
distal pulp of the finger or thumb.
• It differs from the superficial apical infection
involving the distal portion of the pulp skin, which
often responds to a small, deroofing incision
• The organism most frequently cultured from a
pulp space infection is S. Aureus

29. Felon
Pathophysiology
• Infection typically is due to direct inoculation of
bacteria by penetrating trauma but may be
caused by
– hematogenous spread
– local spread from an untreated paronychia.
• Most common in thumb and index finger.
Clinical presentation
• Throbbing pain and
• Tense swelling localized to the pulp

30. Felon
“Don’t wait for fluctuation if tension is
severe”
• Infection results in edema  increased
pressure within the closed compartment
impaired venous outflow  local
compartment syndrome
• Invasion of the bone may lead to
osteomyelitis

31. Treatment
• Surgical decompression.
• One of several incisions can be used,
– unilateral longitudinal incision,
– a J-shaped or hockey-stick incision,
– a through-and-through incision,
– or a volar longitudinal incision. A fishmouth incision should be avoided .
• Although the site of maximal induration often dictates the location of the
incision
•
• Unilateral longitudinal incision is ideally performed on the noncontact surface
of the involved digit. This includes
– the ulnar sides of the index and long fingers and
– the radial sides of the ring finger, small finger, and thumb

32. FIGURE 7. Incisions used for decompression of a felon. A: A
midlateral incision is preferred. B: A J-shaped or hockey-stick
incision. C: A through-and-through incision. D,E: A volar transverse
or longitudinal incision.

33. • The best is a
longitudinal incision
over the area of
greatest fluctuance
because it avoids
– Skin slough
– Digital nerve injury
– Creation of an
unstable fat pad
• To avoid penetration
of the tendon sheath,
the incision should
not extend to the
distal interphalangeal
crease.

34. Additional measures
• Pus should be taken for C&S
• Initial empiric antibiotic coverage with a second-generation
cephalosporin, such as cefazolin, while
awaiting culture identification and sensitivity is usually
adequate.
• Addition of gram-negative coverage is recommended in
an immunocompromised individual.
• Postoperative wound care, edema control, splinting, and
motion optimization are preferably pursued with therapy
supervision

35. Herpetic Whitlow

36. Herpetic whitlow
• Herpetic whitlow is an intensely painful infection
of the hand involving 1 or more fingers that
typically affects the terminal phalanx.
– Commonly involves thumb and index fingers
Risk factors
• Genital herpes in self or partner.
• Health care workers
• Children with gingivostomatitis
Adamson first described herpetic whitlow in 1909, and in 1959, it was noted to be an
occupational risk among health care workers

37. Herpetic whitlow
Symptoms
– Localized pain, pruritus, and swelling followed by the
appearance of clear vesicles
– Typically localized to 1 finger only (symptoms involving more
than 1 finger are more typical of coxsackievirus infection)
 Clear vesicles on an erythematous border localized to 1 finger
 Pain, typically out of proportion to findings
 Edema
 Turbid or cloudy fluid in vesicles possibly suggesting a
superimposed pyogenic infection
 In later stages, coalescence of vesicles to form an ulcer
 Distal finger pulp remains soft, distinguishes HSV infections from
bacterial felon

38. Herpetic whitlow
Diagnosis
• The diagnosis can be confirmed by a Tzanck test, which
demonstrates the presence of multinucleated giant cells in a
scraping taken from the base of an unroofed vesicle.
Treatment
• Self limited disease
• Incision is contraindicated as it spreads the infection may lead to
herpetic encephalitis
• Unroofing relieves the pain
• Topical antifungals can be applied.

39. Web space infections

40. Web space infections
•Communication:
–Palmar surface contiguous
with dorsal subcutaneous
Borders:
–Dorsal / Volar
•Dorsal hand fascia
•Palmar fascia
Radial/Ulnar
Digital extensor
mechanisms and
MCP joint
structures
–Distal
Vertical septae of
palmar aponeurosis,
approx. 2cm proximal
to interdigital webs

41. Web space infections
• Also known as a collar button abscess or hourglass
abscess.
• Involves the subfascial palmar space between the digits
• Begins as an infected blister, an open wound, or a
palmar callus or from the adjacent subcutaneous area.
• An abscess subsequently develops and extends either
volarly or usually dorsally to include the contiguous
subcutaneous space of the dorsal hand

42. Webspace infections
• Clinical presentation
• The involved adjacent digits are held apart
from one another in a characteristic abducted
posture.
• This clinical presentation, combined with
prominent dorsal hand swelling and a tender
palmar web space, usually makes the
diagnosis clear

43. Webspace infections
Treatment
• Incisional drainage is performed with separate dorsal or volar or combined
approaches .
• The type of incision(s) used depends on the location of the abscess.
•
• A combined approach is used in cases in which the infection is noted both
dorsally and volarly.
• A transverse incision in the web space itself should be avoided to prevent
possible web space scar contracture .
• After formal debridement and irrigation of the wound, a 16-gauge
polyethylene catheter can be sutured into an open wound to allow for
subsequent saline irrigation (100 mL per hour) of the wound for 24 to 48
hours.

44. (A) Curved longitudinal volar incision for drainage of a web , (B) Dorsal
incision used in conjunction with A. (C) Volar transverse incision, can cause web
space contracture. (D) Volar exposure, used with dorsal incision B.

45. Dorsal Subaponeurotic Space
Infections

46. Dorsal subaponeurotic space
infections
• The dorsal subaponeurotic space is a
potential space located deep to the extensor
tendons and dorsal to the metacarpals
• Penetrating trauma usually introduces
bacteria to this space, which can subsequently
become an abscess

47. Treatment
• Aggressive surgical incision and debridement are
recommended if in doubt.
• Two dorsal longitudinal incisions are preferable rather than a
single central one, which may result in tendon desiccation.
– One incision is centered over the second metacarpal.
– the other is in the fourth-fifth intermetacarpal region to allow an
adequate intervening skin bridge.
• Care is taken to protect the dorsal veins to minimize hand
swelling.
• The wounds are allowed to heal by secondary intention, and
early hand motion is instituted to minimize extensor tendon
adhesions

49. Palmer space Infections
• The deep palmar spaces are potential spaces
in the hand and are divided into
– The midpalmar space,
– Thenar space,
– Hypothenar space,
– Posterior adductor space

51. Mid palmer space
• The midpalmar space Lies posterior to the long flexor tendons to the middle,
ring and little fingers and in front of the interossei and the 3rd, 4th and 5th
metacarpal bone
• Radially, it is bordered by the midpalmar or oblique fascial septum. This
septum extends from the third metacarpal to the sheath, enclosing the long-finger
flexor tendons (ulnar bursa in some people).
• Distally, the midpalmar space extends to the level of the vertical septa of
the palmar fascia, ending approximately 2 cm proximal to the web spaces.
• Proximally, the space extends to the distal edge of the carpal canal.
– Midpalmer space is continous with the anterior compartment of
forearm ( space of parona) via the carpel tunnel

52. Thenar space
• The thenar space is bordered
– Medially by the vertical midpalmar septum
– Posteriorly and radially by the adductor pollicis
fascia,
– Lies deep to the long flexor tendons to the index
finger and in front of adductor policis muscle
• Communicates with web of thumb and under
flexor retinaculum.

55. Clinical significance of thenar space
• The thenar space lies just superficial to the
adductor pollicis muscle, forming a plane
connecting the deep aspects of the radial
bursa and the ulnar bursa.
• Abscess or space occupying lesions may
spread transversely through the thenar space
deep in the palm between the thumb and the
carpal tunnel

56. Hypothenar space
• The hypothenar space is located ulnar to the
midpalmar space,
– Contains the hypothenar muscles and is enclosed
by their investing fascia.
• This space is bordered radially by a fibrous
hypothenar septum coursing between the
fifth metacarpal and palmar aponeurosis

57. Posterior adductor space
• The posterior adductor space is another
potential space located dorsal to the adductor
pollicis and palmar to the first dorsal
interosseous.

58. Clinical presentation
• Pain
• Erythema
• Swelling ,
• Guarding with tenderness at the focus of
abscess.
• It is not unusual for a patient to present 48 to
72 hours after a penetrating injury with signs
of infection.

59. In midpalmar space infections, the
hand loses its normal palmar
concavity with tenderness and
induration over the palm. There is
dorsal hand swelling and limited and
painful motion of the middle and ring
fingers
In thenar space infections, the thenar
region is dramatically swollen and
exquisitely tender. The thumb is
abducted due to the increased pressure
and volume in the thenar space. Motion
of the thumb and index finger is painful.

60. Surgical incisions used for midpalmar
space infection
• Options include
– a preferred curvilinear longitudinal approach,
– a transverse incision through the distal palmar
crease,
– a distal palmar incision approach through the
lumbrical canal,
– a combined transverse and longitudinal incision.

61. FIGURE 10. Incisions used for
decompression of midpalmar
space infections.. A: A transverse
incision through the distal palmar
crease. B: A distal palmar
incision approach through the
lumbrical canal. C: A combined
transverse and longitudinal
incision. D: A curvilinear
longitudinal approach (Reprinted
from Seiler JG. Essentials of hand
surgery. Philadelphia: Lippincott
Williams & Wilkins, 2002, with
permission. Copyright American
Society of Surgery of the Hand.)

62. Surgical incision for thenar space
infection
• A thenar space infection may require a volar and a
separate dorsal first web space incision (preferred) if
dorsal extension has occurred around the adductor
pollicis and first dorsal interosseous muscles. This is the
so-called dumbbell, or pantaloon, abscess.
– On the volar side, an incision is made adjacent and parallel
to the thenar crease. Great care is taken to avoid injury to
the palmar cutaneous branch of the median nerve in the
proximal part of the incision and motor branch of the
median nerve in a deeper plane.
– A second, slightly curved longitudinal incision is made on the
dorsum of the first web space

63. (A) Volar transverse approach to
the thenar space. Nerve injury is
a potential complication. (B)
Thenar crease approach. Nerve
injury can result from this
approach. It has the added
disadvantage of limited drainage
of the space behind the adductor
pollicis. (C) Dorsal transverse
approach. A contracture of the
web space can result if this
incision is placed too close to the
edge of the web. (D) Dorsal
longitudinal approach to the
thenar space.

64. Incision for hypothenar space

65. Pyogenic Flexor Tenosynovitis
Relevant anatomy
• The flexor sheath is an intricate continuous synovial
sheath originating at the level of the metacarpal neck
and ending at the insertion of the flexor digitorum
profundus.
• It separates into an outer parietal and an inner visceral
layer.
– The parietal layer thickens at different intervals, consistently
forming discrete annular and cruciform pulleys.
– The visceral layer is the epitenon.
– Between the two layers is the synovial space, which is
essentially a closed space

66. Clicinal relevance
• The flexor sheath of the little finger flexor digitorum profundus
tendon (and, on occasion, the ring, long, and index fingers)
communicates with the ulnar bursa, which extends proximal to the
wrist level.
• The flexor sheath of the flexor pollicis longus communicates with the
radial bursa, which extends proximal to the wrist level as well.
• The radial and ulnar bursa can communicate at the level of the
transverse carpal ligament through Parona's space producing a
horseshoe abscess.
• Parona's space is a potential space in the distal forearm located
between the pronator quadratus muscle and the flexor digitorum
profundus tendons.

68. Pyogenic Flexor Tenosynovitis
• Pyogenic flexor tenosynovitis, or suppurative
flexor teno-synovitis, is a bacterial infection of
the digital flexor sheath.
• The majority of these infections are secondary
to traumatic penetrating injuries; therefore,
skin flora, including S. aureus, is the source of
the most common infecting organisms

69. Clinical presentation
• Kanavel's four cardinal signs:
– tenderness along the flexor
sheath
– a semiflexed resting posture
of the involved digit
– symmetric digital swelling
(sausage digit),fusiform
swelling
– pain with passive extension
of the digit (the most
reproducible clinical sign),
*Not all signs may be
present

70. Pyogenic tenosynovitis
of index finger

71. Incisions for drainage of
tendon sheath infections. (A)
Open drainage incisions. (B)
Single incision for instillation
therapy of tendon sheath
infection. (C) Sheath irrigated
via needle proximally and
single distal incision. (D)
Incisions for through-and-through
intermittent
irrigation. (E) Closed tendon
sheath irrigation technique.
(F) Closed irrigation of ulnar
bursa.

72. Radial and ulnar bursa infection
• Infection of both 'bursa' may result from
direct spread proximally along the associated
tendon sheath or from a penetrating injury.
• Treatment is similar to that recommended for
tendon infections:
– open or closed irrigation, leaving a drain in situ
– antibiotic cover

74. Principles of hand incisions
Take home message
• Incisions should be outlined by sterile surgical markers
before making the actual incision to
– confirm appropriate position,
– to confirm the adequacy of skin bridges should multiple
incisions be used,
– to help guide closure.
• Incisions can be made in skin creases on the volar
aspect of the hand but incisions in deep creases should
be avoided due to
– the thin subcutaneous tissue,
– tendency for maceration due to moisture,
– tendency toward poor apposition of skin edges on closure.

75. Principles of hand incisions
Take home message
• Incisions perpendicular to a volar flexion crease should
be avoided
– to prevent scar formation and
– secondary skin contractures that can lead to loss of motion
and functional impairment
• Incisions on the dorsal surface of the hand can be
smaller due to the more mobile and loose nature of the
dorsal skin
• Vertical, horizontal, and curved incisions can all be used
with good facility as long as adequate skin bridges are
maintained

76. Principles of hand incisions
Take home message
• Fingers can be exposed dorsally, volarly, or midaxially.
– Dorsal incisions can be longitudinal or curvilinear.
– Volar incisions are best facilitated by a zigzag pattern that
crosses creases laterally and at angles.
– Midaxial incisions are best placed at the junction of
glabrous and nonglabrous skin, with attention being paid
to the neurovascular bundle that sits in the plane of the
flexor sheath. The neurovascular bundle can be taken
volarly with the volar flap or can be left in place by
carrying the dissection superficial to it.

79. Compartment syndrome of the forearm of an anticoagulated patient after the radial artery
was punctured while obtaining an arterial blood gas.

81. • Apply tourniquet to upper arm if ischemia is not threatening the extremity.
Fasciotomy can be performed without use of tourniquet in emergency or if critical
ischemia time is being approached.
• Exsanguinate the arm with an esmarch bandage and inflate tourniquet to 100mm
Hg higher than systolic pressure.
• Make a curvilinear S-shaped skin incision on the volar aspect of the forearm.
Incision should begin proximally medial to the biceps tendon (apex of flap is radial
to medial epicondyle) and end distally between the hypothenar and thenar
eminences. Make sure to cross flexion creases at an angle to avoid postoperative
linear contractures across the antecubital fossa and wrist. S-shaped incision should
be made in such a way to create a radial sided flap in the mid to distal forearm so
that the median nerve will be covered.
• Proximally, divide the lacertus fibrosis.

82. • Incise and release the superficial volar compartment fascia throughout its entire length.
• Expose the deep compartment of the forearm by retracting the flexor carpi ulnaris and the underlying
neurovascular bundle medially, and then retracting the flexor digitorum superficialis and median nerve
laterally. The flexor digitorum profundus should now be visible.
• Incise and longitudinally release fascia overlying the flexor digitorum profundus.
• Perform carpal tunnel release by incising the transverse carpal ligament along the ulnar border of the
palmaris longus tendon. Ensure median nerve is protected.
• Release ulnar nerve in Guyon’s canal if needed.
• If muscle still appears tense, perform epimysiotomy of individual muscle bellies.
• If median nerve is exposed in distal forearm, suture distal skin flap closed loosely over the nerve (see
image below).
• Leave incision open, do not close the skin.
• Assess dorsal compartments to determine if fasciotomy needed.

83. Dorsal approach for release of dorsal
compartments

84. • Pronate forearm.
• Make dorsal skin incision beginning distal to lateral epicondyle between extensor
digitorum communis and extensor carpi radialis brevis, extending distally
approximately 10 cm towards midline of wrist.
• Gently create skin flaps so that the mobile wad can be identified.
• Release the fascia overlying mobile wad of Henry and the extensor retinaculum.
• Leave skin incision open.
• Apply sterile moist dressings to volar and dorsal skin incisions.
• Place long-arm splint making sure to not flex the elbow beyond 90 º.

85. Hand fasciotomy
Locations for dorsal incisions over second and fourth
metacarpals. Provides access to the dorsal and volar
interosseous compartments and adductor
compartment to the thumb.

86. Hand fasciotomy
Locations for thenar incision over radial aspect of the thumb
metacarpal and mark for the hypothenar incision over ulnar
aspect of the fifth metacarpal.

87. • Apply tourniquet to upper arm if ischemia is not threatening the extremity.
(Fasciotomy can be performed without use of tourniquet in emergency or if critical
ischemia time is being approached.)
• Make 2 dorsal longitudinal skin incisions over the second and fourth metacarpals —
this will allow access to the dorsal and volar interosseous compartments as well as
the adductor compartment to the thumb.
• Use tenotomy scissors to carefully carry incisions down on either side of the
metacarpals to release the dorsal interossei.
• Continue deep dissection on the radial and ulnar borders of the index and ring finger
metacarpals, thus releasing the first palmar interosseus, the adductor compartment
to the thumb, and the palmar interossei.

88. • Make separate longitudinal volar incisions over the thenar and
hypothenar compartments. These incisions should be placed over
the radial aspect of the thumb metacarpal and the ulnar aspect of
the small finger metacarpal, respectively.
• Assess digital swelling and perform digital fasciotomies if
warranted.
• If digital fasciotomy is warranted, place mid-axial lateral incisions on
the ulnar aspect of the index, ring, and long fingers and on the
radial aspect of the thumb and small finger. Place the incision along
the most dorsal portion of the joint flexion creases. A more volar
incision could lead to a flexion contracture.

90. References
• Hand Surgery
– Richard A. Berger
– Arnold-Peter C. Weiss
• Sabiston Textbook of Surgery
• Schwartz's Principles of Surgery, 9th Edition
• Wheeless' Textbook of Orthopaedics
• Medscape