Overview:

A review of common hand soft tissue infections, management of fingertip and nailbed injuries, and finally management of injection injuries.

General Principles: when seeing hand injuries, it is important to make sure tetanus is updated, that hand soaks are initiated following surgical drainage, as well as consideration of patients medical history (IE (IE immunocompromise, diabetics, steroid use, IVDU) and types of infections these populations are prone to–> polymicrobial and gram negative (including farm contamination). Most common organism is staph aureus and b hemolytic strep- panton-valentine leukocidin (PVL) toxin with staph; lymphangitic streaking with beta hemolytic strep. 

• IV abx are recommended for flexor tenosynovitis, septic arthritis, and osteomyelitis
• Bactrim or clinda/cipro first line choices for staph infections followed by down stepping to first generation cephalosporin/amoxicillin if methicillin sensitive 

Generic Soft Tissue Infections 

• Bacterial Infections:

• Cellulitis soft tissue bacterial infection marked by rubor, calor, dolor, and tumor (not yet an abscess) 

• is usually caused by GPC (beta hemolytic sterp most common), staph or strep. Treatment includes do warm soaks or I&D if necessary as well as antibiotics, elevation with or without splinting. 
• Keflex and dicloxacillin are appropriate for oral abx unless MRSA is suspected (vancomycin or clindamycin)

• Subcutaneous abscess: can present after puncture wound or foreign body; same diagnostic criteria as cellulitis but will also have fluctuance. Treatment involves ID of abscess and abx administration (obtain cultures), pack, and initiate soaks (typically BID to TID soaks and packing changes) –> heals by secondary intention or by delayed primary closure after infection as resolved

• Usually IV abx for abscesses –> most common organism if staph aureus (first generation cephalosporin first line treatment)

• MRSA is becoming more common (staph is most common) and empiric treatment should be considered with either clinda or sulfamethaxole –> for farm injuries include pencillin for clostridia
• For diabetic patients consider GMN coverage with gentamycin

• Osteomyelitis: typically from open fracture –>  ex fix, soft tissue infections, bacterial emboli

• Occurs more commonly in patients with PVD or systemic illnesses like immunocompromise, PVD, DM, IVDU
• Diagnosis: persistent/recurring edema, erythema, pain, sometimes drainage. ESR.CRP and WBC may be elevated. CRP is more reliable than ESR for following treatment. 

• Radiographic changes include osteopenia and periosteal reaction –< appear 2-3 weeks after development of symptoms 
• Leukocyte scans are helpful in making diagnosis; can also use MRI
• Treatment: antibiotics, surgical debridement, must debride all sequestrum and necrotic bone

• Antibiotics are tailored to culture results (start with coverage of S aureus) and continue for 4-6 weeks
• If implant is in place, fixation is maintained as long as construct is stable –> wait for union

• Remove implant once fracture is healed
• Reconstruction includes bone grafting with cancellous <1.5cm, corticocancellous for larger defects
• Can use abx spacer for staged reconstruction, using masquelet technique then grafting in 4-6 weeks
• Septic Arthritis: is a bacterial infection of a joint.  can result in permanent cartilage destruction if untreated (mechanism by bacterial toxins and enzymes produced by bacteria

• Can occur by direct trauma or hematogenous spread; wrist most common, PIP second

• Diagnosis: pain increased with joint motion–> edema, swelling, join tenderness (extreme with AROM and PROM, axial loading)

• Joint aspiration for diagnosis –> visual inspection is cloudy, fluid contains >50,000 WBC with increased PMNs (>75%); decreased glucose (40 less than resting BG), bacteria on gram stain, r/o crystals

• Radiographs: reveal foreign body or associated bony injury –> early stage shows joint widening, late changes include joint destruction
• Staph aureus most common, followed by b-hemolytic streptococcus. In peds consider haemophilus influenzae
• Atraumatic SA includes neisseria gonorrhoeae –> common in <30 year old sexually active patients –> more common in women and include low grade fever, chills, and migratory polyarthralgias –> monoarticular arthritis develops in <50% of patients with early symptoms

• Treatment: Surgical decompression with ID –> wound left open or drain is placed –> often need second look with repeat debridement

• Use soaks or whirlpools, gentle ROM, and BID WTD changes, orthosis for comfort
• ABX should include GPC (first generation cephalosporin, clindamycin –> IV abx should be used until visualize improvement, oral abx continues for 2-4 weeks)
• Neisseria SA usually treated non surgically with ceftriaxone followed by 7-10 of oral antibiotics
• Necrotizing fasciitis: severe, life-threatening and limb threatening infection of soft tissues often stemming from laceration or trauma. 

• Risk factors: PVD, DM, immunosuppression, IVDU, chronic liver disease
• Mortality is up to 76% –> delay in diagnosis/treatment is associated with death

• 20% amputation rate

• Type 1- most common and is mix of anaerobic and aerobic organisms (polymicrobial)
• Type 2- group A strep (B hemolytic strep), and staph

• Diagnosed by rapidly progressing infection, poorly demarcated erythema, shiny skin, grey “dishwater” fluid –> patches of bullae and discoloration occur after a few days –> then spreads rapidly dissecting along fascial planes and liquifying fat
• Includes increased WBC count with progression to DIC and shock
• Radiographs may reveal gas in tissues
• Treatment: prompt recognition, early administration of abx, radical surgical debridement –> (all necrotic and fibrinous tissue, liquified fat, and foul smelling dishwater fluid)

• Leave open, return to OR  24/48 hours

• Abx: need broad GPC and GMN and anaerobic coverage : (unsasyn, clindamycin, cipro good combo for GP, GMN, and anaerobes) (cephalospirin, gentamycin, penicillin)
• Gas Gangrene: myonecrosis usually caused by clostridial species (clostridial perfringens) –> begins with open wound with necrosis (think dirty farm wound)

• Skin becomes edematous and bronze with hemorrhagic bullae–> gram stain of drainage reveals spore forming GP rods –> pain increases rapidly –> may feel crepitance on palpation (subcutaneous gas) –> eventual septic shock
• May see gas on radiographs
• Treatment: debridement with open wounds left to drain, abx prophylaxis necessary to prevent this

• Paronychia: infection of the eponychial fold, generally begins by disruption of the barrier between the nail and the underlying tissues (manicures, fake nails, nail biting etc) –> infection begins dorsal to nail and may spread superficially around nail (hyponychium area of most resistance to treatment of infection)

• Most common organism is polymicrobial (staph very common)
• Treatment: drainage, soaks, and abx–> use local and separate eponychial fold from nail –> may remove portion of the nail if there is a subungual abscess –> soaks and dressing changes
• Chronic paronychia may be treated by marsupialization (excising the skin proximal to the nail fold) of the skin proximal to the eponychial fold and allowing wound to heal secondarily

• Nail plate appears abnormal with thickening or grooving

• Secondary to frequent water immersion
• Polymicrobial or candida
• Felon: abscess of finger tip –> fingertip composed of series of fascial septa running from distal phalanx to the skin –> often after a wound –> most commonly staph aureus

• Early cases may be treated with soaks and abx –> drainage when abscess –> usually midaxial incision (radial side of small finger and thumb, ulnar on index, long, ring) –> decompress with clamp to disrupt fibrous septate –> pack and 
• Treat this as it can progress to osteo or flexor teno

• Dr. Cendales, can you describe the best way to drain a felon effectively? 

• Flexor Tenosynovitis: defined as purulence within the flexor sheath –> can result in tendon necrosis and rupture –> staph most common after penetrating trauma 

• Diagnosis: Kanavel’s four signs (fusiform swelling of the digit, resting flexed posture of the digit, pain to palpation along the flexor sheath)

• Most common signs pain with passive extension and fusiform swelling
• Most SENSITIVE is pain along the flexor sheath

• Remember the potential spaces –> small finger sheath –> ulnar bursa –> parona space OR thumb flexor sheath –> radial bursa (either of these can create horseshoe abscess)
• Treatment: surgical decompression –> two incisions (oblique incision at level of distal palmar crease and longitudinal midaxial incision at level of distal joint) –> sheath copiously irrigated from proximal to distal –> if this is inadequate then the midaxial incision needs to be elongated and sheath incised between A2 and A4 pulleys
• Post-operative irrigation should be used

• Poor outcomes include reduced total active motion
• Collar-button abscess: (web space abscess) present with abducted digits and pain, edema, erythema –> forms from a distal palmar callus, blister, or fissure and spreads in the proximal part of the finger

• Usually need dorsal and volar incisions –> avoid transverse incisions due to incidence of contractures

• Atypical bacterial infections: most common is mycobacterium marinum and presents with pain, edema and clinical evidence of tenosynotvitis –> slow progression of symptoms –> patients typically present after multiple presentations and failed treatment attempts

• Commonly seen after aquatic exposure
• Tissue biopsy required for diagnosis (think Lowentsein Jensen medium); ziehl Neelsen stain
• Histology includes non caseating granulomas

• Abx: 6 weeks- 2 years; clarithromycin (more severe include sulfonamides, bactrim, ethambutol and rifampin)

• Vibrio vulnificus is a GMN bacillis, cause of necrotizing fasciitis and commonly associated with warm saltwater environments
• Toxic Shock syndrome: toxemia rather than septicemia –> associated with S aureus toxin 1 (TSST1) –> treatment includes debridement, remove implants, clindamycin (inhibits TSST1)

• Strep TSS associated with worse outcomes and mortality

Viral Infections:

• Herpetic Whitlow:  caused by herpes simplex 1 and 2 –> seen on fingertips of children or dental/health personnel (orotracheal secretions)

• Index and thumb most common
• Lesions without pus (vesicles) that coalesce into bullae, unroof, ulcerate
• Symptoms include fever, malaise, lymphadenopathy (2-14 days after exposure) runs self limited course
• Contagious until lesions have healed

• Diagnosis made with PE, culture, and analysis with Tzanck smear (frequently looks like paronychia or felon)
• Do not debride –> can cause secondary infection
• Most common hand lesion in HIV patients
• Is self limiting or treated with antivirals (acyclovir and valcyclovir)

Fungal Infections:

• Cutaneous: involve skin or nails. 

• Onychomycosis (tinea unguium) – relatively common infection of the nail caused by dermatophytes such as trichophyton rubrum or candida albicans

• Those with wet or moist hands are susceptible –< will see thickening of paronychium, cracking discoloration and nail disintegration
• Potassium hydroxide (KOH) preparation of nail scrapings for diagnosis
• Treatment: topical or oral antifungals (high recurrence rate) –> if refractory need to removal the nail and use oral antifungals

• Subcutaneous: usually sporotrichosis –> caused by sporothrix schenckii –> found in people who work with plants or roses –> introduces organism into SubQ –> papulonodular lesions ulcerate –> infection spreads through the lymphatic systems –> regional lymph nodes may swell or ulcerate

• Diagnosis made by fungal culture
• Treatment consists of saturated solution of potassium iodide –> itraconazole can be used
• Can spread to bone and joints

• Deep/systemic: include coccidiomycosis, blastomycosis, or histoplasmosis

• Opportunistic infections include aspergillosis, candidasis, mucromycosis, and cryptococcosis
• Rhinocerebral mucurmycosis is an opportunistic infection of the nasal cavity and sinuses à can spread rapidly to the orbits and brain by erosion of the bone and invasion of blood vessels

• Affects those that are immunocompromised (diabetes etc)
• Treat with systemic antifungals, debridement, need rapid diagnosis and intraoperative biopsy with frozen blackish secretions and necrosis of the inferior turbinate and adjacent nasal mucosal tissues

Bites: 

• Dog and cat bites: cats have higher rates of infection, organism is pasteurella multicoda (anaerobes, staph, strep can also be found)

• Treatment with augmentin or unasyn (if allergic treat with doxy, bactrim, or flouroquinolone plus clindamycin)
• Rabies exposure includes inocculation in the wound with immunoglobulin and vaccine
• Prophylaxis is vaccine only
• Remember cat scratch carries risk of bartonella (will see lymphadenopathy, malaise, recurring fevers) –> need to test titers –> treatment with azithro, cipro, and doxy

• Human bites: “fight bites”–> present with pain, swelling –> typically intra-articular –> should have low threshold take to OR 

• Staph, strep, eikenella (long and ring finger most common) 
• Treatment is OR for ID, augmentin/ unasyn 

• Spider bites: recluse (local necrosis); widow spiders may need antivenom
• Lyme’s disease: most common tick borne disease, borrelia burgdoferi –> early is skin lesions and erythema migrans –> can progress to neurologic/cardiologic and 

• Diagnosed by western blot
• Doxy

• Leeches: aeromonas hydrophilia- GNR (treat with bactrim, cipro, and third generation cephalosporin), prophylaxis recommended

Potential Spaces for infections: lie between muscle fascia plans

• Midpalmar space- can originate with flexor tenosynovitis of long, ring, or small finger

• Volar palmar interossei and FDP tendons (2nd and 3rd interossei)
• Drain with a straight transverse incision

• Thenar Space- will experience palmar abduction of the thumb, passive ROM increases pain (need dorsal and volar incisions)

• Bt adductor pollicis and index flexor tendons (radial to the third metacarpal)
• Most common deep space infection and will hold fingers in abduction to minimize pressure

• Can drain dorsal/volar or combined incision

• Hypothenar Space-located ulnar to midpalmar space –> composed of hypothenar muscles surrounded by their enveloping fascia
• Parona Space- bounded by PQ, digital flexors, FPL, and a vertical band of fascia radial to FCU and ulnar NV bundle –> becomes infected from either radial or ulnar bursa –> presents as tender erythematous fullness palpable at the volar wrist crease level –> can also see median nerve symptoms

• Extended carpal tunnel release for drainage

• Dorsal subaponeurotic space: contained by extensor tendons and fascia dorsally and interosseous muscles and metacarpals palmarly –> drainage by incisions over second and fourth metacarpals

• Postoperative Infections: typically GP organisms –> 3-7 days after surgery

• Do not need antibiotic prophylaxis in clean, elective hand surgery cases that are <2 hours
• First generation cephalosporins, clinda/vanc used for allergies
• SSI infection defined as soft tissue infection within 30 days of surgery or 1 year of prosthetic implant

• Infections in Post-Traumatic Wounds: no need for routine abx in healthy patients with uncomplicated soft tissue wounds w/o bone, joint or tendon involvement

Mimickers of Hand Infections

• Crystalline arthropathy: gout and pseudogout –> have clinical presentation similar to that of septic arthritis –> joints are painful, edematous, swollen, tender
• Arthrocentesis/radiographs/hx may differentiate (ask about similar attacks in the past)

• Negatively birefringent (urate crystals), weakly positively birefringent crystals (CPPD)

• Most common is first MTJ *(great toe)

• Chondrocalcinosis can be seen on radiographs (particularly at TFCC)
• Send absolute alcohol level
• Therapy includes (orthosis, anti-inflammatory, colchicine, NSADs)
• Pyogenic granuloma: red, friable masses that penetrate through skin and can be prominent/dramatic in appearance (can be response to a wound)
• Cauterize with silver nitrate, excision curative

• Pyoderma gangrenosum: associated with systemic diseases (UC/Crohns) –> presents as small painful ulcer that enlarges, undergoes central necrosis
• Treatment includes biopsy, steroids and treatment of underlying cause
• Do not debride!
• Neoplasia: can ulcerate and develop secondary infections (be aware of long standing lesions)
• Send for biopsy prior to treatment

• Acute calcific tendinitis: erythema, pain, occasional fever –> pain is localized over tendon/ligament that contains calcium deposit –> diagnosis by radiographs (pisiform common)
• Resolves without treatment