2. Hand Infections

3. Hand Infections
Introduction
 In the pre-antibiotic era:
 65% of hand disability resulted from minor injuries that became
infected
 50 - 75% of all hand deformities were the result of infection
 Kanavel’s study of the surgical anatomy of the hand:
 defined anatomical planes and channels
 careful placement of incisions for optimal drainage
 became the cornerstone of treatment in the pre-antibiotic era
 Penicillin changed the landscape:
 severe hand infections are relatively uncommon today
 incidence stable since 1940’s

4. Hand Infections
Antibiotics
 valuable adjunct in infections but used alone will effect a cure
in only a limited number of situations
 early diagnosis: 24 - 48 hrs.
 high dose IV therapy
 elevation & splinting to rest the affected part
 Beyond this time success is unlikely:
 thrombosis of small vessels
 swelling & pressure within closed anatomical spaces
 Abx need not be continued more than 7 - 10 days
 exception: osteomyelitis
 can usually switch to oral route in 2 - 3 days (if improving)

5. Hand Infections
Outline
 Principles
 High Risk Patients
 Felons & Paronychia
 Flexor Tenosynovitis
 Deep Space Infections
 Bites
 IDU
 Osteomyelitis
 Septic Arthritis
 Chronic Infections

6. Hand Infections
Introduction
 Treatment principles
 early & adequate decompression of pus to avoid soft
tissue loss
 proper placement of incisions
 avoids damage to adjacent structures
 minimizes scar contracture
 appropriate debridement of necrotic tissue
 judicious splinting & early mobilization to minimize joint
stiffness
 appropriate use of Abx as adjunct to prevent
dissemination of established infection

7. Hand Infections
Introduction
 For infections requiring drainage, pre-operative planning is
required. Type & placement of incision should:
 Allow direct access to
the abscess cavity
 Permit easy extension
in any direction
 Follow accepted principles
of hand surgery

8. Hand Infections
Introduction
 Principles:
 carry out procedure with optimal lighting, positioning,
visualization, analgesia & tourniquet control
 Do not exsanguinate part as this may cause bacterial seeding
 incisions don’t cross flexion creases at > 45°
 avoid injury to vessels, nerves & tendons
 avoid compromising the blood supply to adjacent area
 avoid leaving a sensitive scar, especially in an important
tactile area
 wounds left open are packed for 48 - 72 hrs. followed by
saline soaks & exercise

9. Hand Infections
High Risk Patient
 Up to 50% of hand infections involve:
 Diabetic / Immune compromised
 IDU
 Bites
 Higher risk for developing severe complications:
 Joint stiffness - Osteomyelitis
 Contracture - Necrotizing Fasciitis
 Amputation - Death

10. Felons & Paronychia
General
Account for ~ 1/3 of hand infections

11. Felons
Anatomy of the fingertip
 Distal phalanx is a closed sac separate from the remainder of
the digit
 Closed pulp space divided into a latticework by multiple septa
 Interstices filled with eccrine glands & fat
 Dorsum is rigid (bound by DP & perionychium)
 An increase in pressure of this compartment can adversely
affect the blood supply to the soft tissue & bone.

12. Felons
 palmar closed-space infection of the distal pulp
 severe pain, redness & swelling
 Hx of minor penetrating trauma is usually present:
 Minor cuts
 Splinters
 Glass slivers
 most frequent causative agent: S. Aureus
 untreated felons can:
 extend toward the phalanx --> osteomyelitis
 toward the skin --> draining sinus
 obliterate vessels ---> skin slough or necrosis
 supperative flexor tenosynovitis or septic arthritis of the DIPJ

13. Felons
Treatment
 If recognized early (mild cellulitis): soaks & Abx
 Later (abscess formation): surgical drainage
 Usually process has been going on > 48 hrs.
 Principles:
 Avoid injury to n/v structures
 Utilize an incision that won’t leave a disabling scar
 Do not violate flexor sheath (stay distal)
 Produce adequate drainage

14. Felons
Treatment
 Multiple incisions described:
 Fishmouth
 J or hockey stick Poor choices:
- painful scar
 Through & through - unstable tip
- anaesthetic tip
 Volar transverse
Risks injury to digital
 Midvolar longitudinal
nerve
 Unilateral high midlateral

15. Felons
Treatment
Palmar incisions through the center of the pulp
 Avoid crossing the DIP flexion crease (contracture)
 Blade should only penetrate the dermis to avoid n/v structures and
then a clamp is used to spread the subcutaneous tissue
 typically, drain over area of maximal tenderness or sinus
 Disadv:: scar over tactile surface, risk injury to dig. nerve

16. Felons
Treatment
Unilateral longitudinal Incision
 Best approach for most felons
 Incise on lateral aspect of digit 5mm dorsal & distal to the DIP flexion
crease
 Continue distally to a point 5mm away from the edge of the free nail
 Deepen the incision with a clamp within a plane just volar to the
palmar cortex of the DP
Location of Incisions:
Index, middle & ring: ULNAR SIDE
Thumb & small: RADIAL SIDE

17. Paronychia
Anatomy

18. Paronychia
 infection in and around the nail fold
 Acute: any break in the seal between the nail and nail fold
may serve as a portal of entry for infection
 hangnails
 manicures
 nail biting
 usual causative agent: S. Aureus
 in more advanced infections, pus may accumulate beneath the nail plate,
separating it from the underlying nail bed. This infection involves the
entire eponychium and is called an “eponychia”
 Pus can also spread around the nail fold resulting in a “runaround
infection”

19. Paronychia
Treatment
 If recognized early (mild cellulitis): soaks & Abx
 Larger infections: drainage through the nail fold
 Paronychial fold & portion of adjacent eponychium:
 Remove 1/4 of nail
 If this doesn’t allow drainage, incise fold away from matrix

20. Paronychia
Treatment
 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

21. Chronic Paronychia
 Slightly different disease process with an indolent course
marked by exacerbations & remissions
 Etiology: proximal nail fold obstruction + fungal infection
 Often seen in people whose hands are constantly in a moist
environment
 Inflammation of the eponychial fold, often with separation
from the underlying nail and intermittent drainage
 usual causative agent: fungus > gram negative bacteria
 Tx: eponychial marsupialization + topical antifungal
 Crescent-shaped piece of skin excised proximal to nail fold
 medical tx alone is largely unsuccessful

22. Tenosynovitis
Anatomy
 Flexor sheaths are closed spaces
 Extend from the mid-palmar crease
to the DIPJ
(Prox edge of A1 pulley to distal edge of A5 pulley)
 Flexor sheath of small finger is
continuous proximally with the
Ulnar Bursa, while the sheath of
the thumb is continuous with the
Radial Bursa
 Radial & Ulnar bursae extend
proximal to the TCL and connect
with the Parona space
(Potential space between FDP & PQ muscle)

23. Tenosynovitis
General
 Flexor sheath infections most often as a result of penetrating
trauma
 More likely at joint flexion creases
 Sheaths are separated from skin by only a small amount of
subcutaneous tissue here
 Also, Felons can rupture into the distal flexor sheath
 Usual causative agent: S. Aureus
 most commonly affected digits:
 Ring, long & index fingers

24. Tenosynovitis
General
 Purulence within the sheath destroys the gliding mechanism,
rapidly creating adhesions that lead to loss of function
 destroys the blood supply producing tendon necrosis

25. Tenosynovitis
Clinical
 Kanavel’s 4 cardinal signs:
 Tenderness over & limited to the flexor sheath
 Symmetrical enlargement of the digit (“fusiform”)
 Severe pain on passive extension of the finger (> proximally)
 Flexed posture of the involved digit
 Not all four signs may be present early on
 Most reliable sign: pain w. passive extension
 Cellulitis of the hand may appear similar, but swelling &
tenderness is not usually isolated to a single digit

26. Tenosynovitis
Treatment
 Early infection < 48 hrs (& usually lacking all 4 signs) may
initially be treated with IV Abx, splinting & elevation
 Failure to respond within 24 hrs. should necessitate drainage
 Established pyogenic tenosynovitis
is a surgical emergency
 Requires prompt surgical drainage
 Delays may result in tendon
&/or skin necrosis

27. Tenosynovitis
Treatment
 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

28. Tenosynovitis
Treatment
 Closed tendon-sheath irrigation:
 2 incisions made
 Proximal palm: open the sheath proximal to the A1 pulley
 Distal mid-axial: open sheath distal to the A4 pulley
 Long irrigation catheter (16 - 18g) is placed in the proximal sheath
with a drain left in the distal incision
 Incisions are then closed, and sheath is irrigated for 48 - 72 hrs.
 May use NS or Abx solution (continuous drip or q2h flush)
 Addition of marcaine alleviates pain of irrigation
 Modification involves multiple transverse incisions of cruciate pulleys
with insertion of silastic drains

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

30. Chronic Tenosynovitis
 Unusual cases may be seen which present differently than
acute pyogenic infections:
 Chronic swelling of the flexor sheath
 No disabling pain or loss of function
 These are chronic infections most frequently caused by
mycobacteria
 usually the result of a puncture wound in an aquatic environment
 M. Kansasii or M. Marinarum
 Dx: AFB stains & culture of synovium
 Tx: tenosynovectomy + antituberculous drugs (6 - 24 mo)

31. Deep Space Infections
 4 deep spaces clinically significant in hand infections:
 Subfascial palmar space
 Dorsal subaponeurotic space
 Thenar space
 Midpalmar space

32. Deep Space Infections
Subfascial Palmar Space Infections
 subfascial palmar space communicates with the dorsal
subcutaneous space via web spaces between the digits
 usually spread dorsally (“collar button abscess”)
 Double abscess: +/- palmar & dorsal abscesses connected through
hole in fascia
 Palmar spread is limited by the relationship of fascia to skin
 Causes:
 Fissure in the skin between the fingers
 Distal palmar callus (MC head)
 Extension from subcutaneous infection in proximal finger
 Severe distal palmar swelling with an abducted finger
 Puss-filled web spaces

33. Subfascial Palmar Space Infections
Treatment
 2 important points:
 Do not incise web space transversely
 Be alert for the double abscess configuration
 Drainage is via a palmar approach with division of the palmar
fascia to expose both the volar & dorsal compartments

34. Deep Space Infections
Dorsal Subaponeurotic Space Infections
 DSS is beneath the extensor tendons on the dorsum of the
hand
 Often the result of penetrating trauma
 IDU’s
 neglected human bites
 Dorsal swelling, erythema & tenderness + history make the
diagnosis
 Drain via linear incisions over the 2nd & 4th MC’s while
preserving soft tissue coverage over the tendons
 occasionally direct incision over a pointing abscess is necessary
 Risks exposure (desiccation) of extensor tendons

35. Deep Space Infections
Thenar Space Infections
 Thenar space follows the direction of Adductor Pollicis:
 Dorsal: AP muscle
 Volar: index flexor &
1st lumbrical
 Radial: insertion of AP
(proximal phalanx of the thumb)
 Ulnar: oblique septum from
skin to the 3rd MC

36. Thenar Space Infections
Clinical
 Causes:
 penetrating injury
 thumb or index subcutaneous abscess
 thumb or index flexor tenosynovitis
 extension from radial bursa or
midpalmar space
 marked swelling of the thenar
eminence & 1st web space
 thumb forced into abduction
 severe pain with extention or opposition
 infection tracks dorsally via 1st web space,
over the AP & 1st dorsal interosseous muscles.

37. Thenar Space Infections
Treatment
 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

38. Deep Space Infections
Midpalmar Space Infections
 Boundaries:
 Dorsal: intrinsic muscles
 Volar: flexor tendons
 Radial: oblique septum from
the skin to the 3rd MC
 Ulnar: hypothenar muscles
 Distal: vertical septa of palmar fascia
 Prox: fascial layer at distal carpal tunnel

39. Deep Space Infections
Midpalmar Space Infections
 Clinical:
 usually due to direct penetrating trauma, rupture of tenosynovitis
 loss of palmar concavity, dorsal swelling, tenderness volarly

40. Midpalmar Space Infections
Treatment
 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.

41. Bursal Infections
 Usually due to spread of flexor tenosynovitis from thumb or
small finger
 Radial bursa:
 Proximal extension of
tendon sheath of FPL
 extends through the carpal
tunnel into the distal forearm
 Ulnar bursa:
 Proximal extension of tendon
sheath of FDP of small finger

42. Bursal Infections
Treatment
 Closed irrigation using 2 incisions, a catheter & a drain as
previously outlined.

43. Human Bites
 Often undertreated & misdiagnosed leading to significant
morbidity
 The most serious form of human bite infection is the clenched
fist injury:
Any laceration over the head of a metacarpal
is a human bite injury until proven
otherwise

44. Human Bites
 The wound that results from a punch to the mouth may
appear insignificant and treatment may not be sought for
days.
 It often results in immediate inoculation of the subcutaneous
tissue, the subtendinous space and the MCP joint with saliva
 Human saliva may contain over 108 microorganisms per ml.
 Over 42 species of bacteria identified
 Thus: Polymicrobial infection is the rule
 Common organisms:
 S. Aureus, Strep sp.,
 Eikenella: gram neg facultative anaerobe in ~ 30% (incr. severity)

45. Human Bites
 Delay in onset of treatment is directly proportional to poor
outcomes:
 In general, human bites treated within 24 hrs. rarely have serious
complications
 in E.D.:
 Debride, irrigate, pack open
 Abx to cover gram +’s & eikenella (Pen & Ceph)
 +/- admission to follow response
 To O.R.:
 Established joint space penetration, & more severe infections

46. Animal Bites
 Dog more common than cat (5%)
 Cat bites are particularly virulent & can result in deep puncture
wounds that are hard to clean
 More than half involve kids
 Basic principles of debridement & irrigation apply
 Deep puncture wounds are left open & may require extension
 Established infections are debrided & packed open
 Superficial lacerations may be loosely closed after irrigation
 Common organisms:
 S. Aureus, Strep viridans, Pasturella (#1 in cats), anaerobes
 Abx: ampicillin (Clavulin on outpatient basis)

47. Injection Drug Use
 Common sites of infection:
 Dorsum of hand
 Radiodorsal area of the wrist
 Palmar aspect of the forearm
 Dorsum of the fingers at the PIPJ
 Clinical spectrum:
 Cellulitis
 Subcutaneous abscess
 Flexor tenosynovitis
 Septic joints
 Osteomyelitis
 Necrotizing fasciitis

48. Injection Drug Use
 Source of infection from a variety of sources
 Skin
 Saliva
 Bowel
 Tx:
 Admission
 elevation of limb
 broad spectrum IV Abx
 analgesia (may need support from APS or CDRT)
 +/- debridement & irrigation
 Medicine consult

49. Hand Infections
Osteomyelitis
 Almost always the result of adjacent spread
 wound infection
 joint infection
 tenosynovial infection
 Also, direct penetration
(hematogenous spread is rare)
 most commonly S. Aureus
 Bone necrosis: hallmark
 microorganisms reside in dead bone
 If caught early, before extensive bone necrosis occurs, it may
be cured with Abx alone.

50. Osteomyelitis
Diagnosis
 Xrays:
 Early radiographs may be normal
 It takes at least 10 days for matrix
to mineralize & areas of increased
density to be detected.
 Lytic lesions; sclerosis (1 month)
 Bone Scan:
 Can pick up osteomyelitis early, but less specific
 Prompt surgical exploration is the most reliable way to
establish the diagnosis

51. Osteomyelitis
Treatment
 Approach depends on location of involved bone:
 Phalanx: mid-axial incision
 Metacarpals: dorsal approach
 all infected bone must be removed
 Soft bone may be curetted
 may need to use drill holes to remove a small window of cortical bone
for decompression of the infection
 routine post-Op care or may also use constant irrigation
methods (1 wk)
 severe, extensive involvement of a digit may be best treated
by amputation
 Will prevent stiffness & major disability of the uninfected parts

52. Hand Infections
Septic Arthritis
 usually the result of penetrating trauma:
 bite or tooth wound
 also, spread from soft tissue or bony infection
 joint is swollen, warm & tender
 pain with axial loading
 passive motion is restricted & painful
 Xrays:
 thinning of joint (cartilagenous loss)
 resorption of subchondral bone
 osteomyelitis (late)
 aspiration of joint for C & S

53. Septic Arthritis
Treatment
 Drainage is imperative as soon as the diagnosis is made
 Destruction of the articular cartilage by lysozymal activity
 approach is through a longitudinal dorsolateral incision over
the affected joint
 access to the joint is via an incision dorsal to the cord portion
of the collateral ligament
 joint is irrigated & debrided
 packed open for 48 - 72 hrs. (or closed over irrigation)
 packing removed and gentle ROM begun
 wound granulates closed

54. Hand Infections
Chronic Infections
 Atypical mycobacterium infections:
 penetrating wound often in a marine environment
 prolonged, relatively non-painful swelling of finger, palm or wrist
 Tuberculous & atypical mycobacteria have a predilection for synovial
tissue of joints & tendon sheaths
 Tenosynovium is thick, infected & hypertrophic. It surrounds the
tendons & erodes the pulleys.
 Dx: culture synovial biopsy
 Noncaseating granulomas & AFB
 Tx: thorough joint synovectomy
 For ++ joint damage: rest the joint until the infection is cured before
undertaking reconstruction
 For tenosynovium: complete synovectomy sparing the pulleys
 Start anti-TB meds empirically (around time of synovectomy)

55. Hand Infections
Chronic Infections
 Tuberculous Infections:
 less common now than several decades ago
 Presents in a similar manner as atypical mycobacterial
infections
 Tx: as above, synovectomy + anti-TB drugs
 In addition, can produce a dactylitis
 Enlarged fingers
 Proliferation of subperiosteal reaction on Xray
 Tx: surgical excision & curettage of the involved areas

56. Hand Infections
Chronic Infections
 Leprosy:
 M. lepraemurium
 Predilection for cooler areas of the body including the hands
 Most frequently produces a neuropathy involving the ulnar nerve:
 intrinsic atrophy
 clawing
 weakness in pinch
 Tx: surgical procedures limited to reconstruction for the neurological
deficits

57. Hand Infections
Chronic Infections
 Fungal Infections:
 except for biopsy for diagnostic purposes, surgical treatment is rarely
necessary
 best treated with systemic &/or local anti-fungal agents
 occasionally a tenosynovitis, septic arthritis or osteomyelitis is seen:
 Appropriate debridement required as above
 Mainstay is still anti-fungal agent

58. Post Op Care
 Wound care & early initiation of therapy are key in achieving
good functional results in treating hand infections
 In general:
 wounds are debrided, irrigated & packed open
 packing usually removed 24 - 48 hrs. post-op
 initiation of regular wound cleansing
 gentle active ROM
 splints may be helpful in enhancing joint motions
 early involvement of a hand therapist is important in achieving a good
functional result.