Hand Infections
Hand Infections                           Introduction In the pre-antibiotic era:    65% of hand disability resulted fro...
Hand Infections                              Antibiotics valuable adjunct in infections but used alone will effect a cure...
Hand Infections                            Outline   Principles   High Risk Patients   Felons & Paronychia   Flexor Te...
Hand Infections                        Introduction Treatment principles   early & adequate decompression of pus to avoi...
Hand Infections                              Introduction For infections requiring drainage, pre-operative planning is  r...
Hand Infections                           Introduction Principles:    carry out procedure with optimal lighting, positio...
Hand Infections                       High Risk Patient Up to 50% of hand infections involve:    Diabetic / Immune compr...
Felons & Paronychia                           GeneralAccount for ~ 1/3 of hand infections
Felons                 Anatomy of the fingertip Distal phalanx is a closed sac separate from the remainder of  the digit ...
Felons palmar closed-space infection of the distal pulp severe pain, redness & swelling Hx of minor penetrating trauma ...
Felons                            Treatment If recognized early (mild cellulitis): soaks & Abx Later (abscess formation)...
Felons                             Treatment Multiple incisions described:    Fishmouth    J or hockey stick           ...
Felons                           TreatmentPalmar incisions through the center of the pulp    Avoid crossing the DIP flexi...
Felons                            TreatmentUnilateral longitudinal Incision    Best approach for most felons    Incise o...
Paronychia Anatomy
Paronychia infection in and around the nail fold Acute: any break in the seal between the nail and nail fold  may serve ...
Paronychia                             Treatment If recognized early (mild cellulitis): soaks & Abx Larger infections: d...
Paronychia                            Treatment Eponychia:    Elevate eponychial fold and excise prox 1/3 of nail    La...
Chronic Paronychia Slightly different disease process with an indolent course  marked by exacerbations & remissions Etio...
Tenosynovitis                                     Anatomy Flexor sheaths are closed spaces Extend from the mid-palmar cr...
Tenosynovitis                              General Flexor sheath infections most often as a result of penetrating  trauma...
Tenosynovitis                         General Purulence within the sheath destroys the gliding mechanism,  rapidly creati...
Tenosynovitis                                Clinical Kanavel’s 4 cardinal signs:      Tenderness over & limited to the ...
Tenosynovitis                           Treatment Early infection < 48 hrs (& usually lacking all 4 signs) may  initially...
Tenosynovitis                           Treatment 2 basic approaches:    Open vs. Closed Open drainage:    Decompressi...
Tenosynovitis                            Treatment Closed tendon-sheath irrigation:    2 incisions made    Proximal pal...
Tenosynovitis                          Treatment These incisions:    ensure adequate drainage    heal quickly    Do no...
Chronic Tenosynovitis Unusual cases may be seen which present differently than  acute pyogenic infections:    Chronic sw...
Deep Space Infections 4 deep spaces clinically significant in hand infections:      Subfascial palmar space      Dorsal...
Deep Space Infections      Subfascial Palmar Space Infections subfascial palmar space communicates with the dorsal  subcu...
Subfascial Palmar Space Infections                            Treatment 2 important points:    Do not incise web space t...
Deep Space Infections  Dorsal Subaponeurotic Space Infections DSS is beneath the extensor tendons on the dorsum of the  h...
Deep Space Infections               Thenar Space Infections Thenar space follows the direction of Adductor Pollicis:    ...
Thenar Space Infections                                 Clinical Causes:       penetrating injury       thumb or index ...
Thenar Space Infections                            Treatment Drain via volar or dorsal incisions  in the 1st web space or...
Deep Space Infections             Midpalmar Space Infections Boundaries:    Dorsal: intrinsic muscles    Volar: flexor ...
Deep Space Infections              Midpalmar Space Infections Clinical:    usually due to direct penetrating trauma, rup...
Midpalmar Space Infections                             Treatment Drain via wide palmar incisions  with +/- resection of p...
Bursal Infections Usually due to spread of flexor tenosynovitis from thumb or  small finger Radial bursa:    Proximal e...
Bursal Infections                         Treatment Closed irrigation using 2 incisions, a catheter & a drain as  previou...
Human Bites Often undertreated & misdiagnosed leading to significant  morbidity The most serious form of human bite infe...
Human Bites The wound that results from a punch to the mouth may  appear insignificant and treatment may not be sought fo...
Human Bites Delay in onset of treatment is directly proportional to poor  outcomes:    In general, human bites treated w...
Animal Bites Dog more common than cat (5%)    Cat bites are particularly virulent & can result in deep puncture     woun...
Injection Drug Use Common sites of infection:      Dorsum of hand      Radiodorsal area of the wrist      Palmar aspec...
Injection Drug Use Source of infection from a variety of sources    Skin    Saliva    Bowel Tx:       Admission    ...
Hand Infections                        Osteomyelitis Almost always the result of adjacent spread    wound infection    ...
Osteomyelitis                              Diagnosis Xrays:    Early radiographs may be normal    It takes at least 10 ...
Osteomyelitis                             Treatment Approach depends on location of involved bone:    Phalanx: mid-axial...
Hand Infections                        Septic Arthritis usually the result of penetrating trauma:    bite or tooth wound...
Septic Arthritis                             Treatment Drainage is imperative as soon as the diagnosis is made    Destru...
Hand Infections                      Chronic Infections Atypical mycobacterium infections:    penetrating wound often in...
Hand Infections                   Chronic Infections Tuberculous Infections:    less common now than several decades ago...
Hand Infections                     Chronic Infections Leprosy:    M. lepraemurium    Predilection for cooler areas of ...
Hand Infections                     Chronic Infections Fungal Infections:    except for biopsy for diagnostic purposes, ...
Post Op Care Wound care & early initiation of therapy are key in achieving  good functional results in treating hand infe...
Hand infections
Hand infections
Hand infections
Hand infections
Hand infections
Hand infections
Hand infections
Hand infections
Hand infections
Hand infections
Hand infections
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Hand infections

  1. 1. Hand Infections
  2. 2. 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
  3. 3. 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)
  4. 4. Hand Infections Outline Principles High Risk Patients Felons & Paronychia Flexor Tenosynovitis Deep Space Infections Bites IDU Osteomyelitis Septic Arthritis Chronic Infections
  5. 5. 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
  6. 6. 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
  7. 7. 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
  8. 8. 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
  9. 9. Felons & Paronychia GeneralAccount for ~ 1/3 of hand infections
  10. 10. 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.
  11. 11. 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
  12. 12. 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
  13. 13. 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
  14. 14. Felons TreatmentPalmar 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
  15. 15. Felons TreatmentUnilateral 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
  16. 16. Paronychia Anatomy
  17. 17. 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”
  18. 18. 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
  19. 19. 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
  20. 20. 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
  21. 21. 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)
  22. 22. 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
  23. 23. 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
  24. 24. 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
  25. 25. 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
  26. 26. 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
  27. 27. 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
  28. 28. 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
  29. 29. 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)
  30. 30. Deep Space Infections 4 deep spaces clinically significant in hand infections:  Subfascial palmar space  Dorsal subaponeurotic space  Thenar space  Midpalmar space
  31. 31. 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
  32. 32. 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
  33. 33. 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
  34. 34. 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
  35. 35. 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.
  36. 36. 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
  37. 37. 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
  38. 38. Deep Space Infections Midpalmar Space Infections Clinical:  usually due to direct penetrating trauma, rupture of tenosynovitis  loss of palmar concavity, dorsal swelling, tenderness volarly
  39. 39. 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.
  40. 40. 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
  41. 41. Bursal Infections Treatment Closed irrigation using 2 incisions, a catheter & a drain as previously outlined.
  42. 42. 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
  43. 43. 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)
  44. 44. 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
  45. 45. 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)
  46. 46. 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
  47. 47. 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
  48. 48. 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.
  49. 49. 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
  50. 50. 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
  51. 51. 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
  52. 52. 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
  53. 53. 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)
  54. 54. 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
  55. 55. 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
  56. 56. 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
  57. 57. 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.

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