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Flashcards in Hand Infections Deck (50)
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How do you classify hand infections

  • Acute vs chronic
  • By anatomic site
    • skin, subcut, deep space, tendon, muscle, 
  • By organism
    • bac, viral, fungal, parasitic, protozoal
  • By etiology
    • trauma, human/animal bute, IVDU, immunocompromise, post-op



What special tests are used for identification of fungal, mycobacteria and HSV infections?

  • Fungal: KOH, Giemsa, Silver stains
    • Hyphae, spores, mycelia
  • Mycobacteria/Nocardia: Ziehl-Niessen stain
  • HSV: Tzank smear


What are treatment principles of hand infection

  • Debridement
  • I&D
  • Splint, Elevation, Rest
  • Antibiotics
  • Early rehab
  • For surgical Tx
    • dont exsanguinated for tourniquet
    • local takes longer to work
    • plan for extension of incisions not over NV bundles
    • plan for multiple washouts
    • cultures from intraop samples
    • Joints - avoid aspiration over area of cellullits
    • Send joint fluid for cell count, C&S, Glc, protein


What are approaches to joints for washout of infection

  • Radio carpal jt - b/w 3/4 compartments
  • MCP jt - dorsal and split extensor
  • PIP jt - midaxial, split TRL, protect central slip
  • DIP jt - H or Y incision, protect TT


What are mimickers of infection to keep on DDX

  • Gout/Pseudogout
    • sent jt aspirate for crystals, Rheum referral
  • Acute calcific tendonitis
    • NSAIDs, Rheum referral
  • FB
  • Pyogenic granulosum
    • excise and cauterize base
  • Pyoderma gangrenosum
    • macult->papule w raise violaceous borders, associated w UC. 
    • Do not excise - treat w steroids and wound care
  • Spider bite
    • brown recluse spider leads to ST necrosis
  • Metastatc or 1' tumor
    • SCC BCC melnaoma KA
    • DP primary site for bone mets (source thyroid, prostate, breast, lung, kidney, colon


What are the 3 potential spaces for infections in the hand and forearm

  • Hand
    • thenar
    • hypothenar
    • midpalm
  • Forearm
    • Paronas space


What are the 9 spaces (includes 4deep and 5 superficials)


  • thenar
  • hypothenar
  • midpalm
  • Paronas


  • dorsal subcutaneous
  • dorsal subaponeurotic
  • interdigital webspace
  • radial bursa
  • ulnar bursa


Define boundaries of thenar space deep infection, symptoms/signs and treatment


  • Roof: D2 flexor sheath and palmar fascia
  • Floor: Adductor fascia
  • ulnar border: D3 MC vertical septum to palmar fascia
  • radial border: confluence of AddP fascia and muscle at insertion to PP

Findings: thumb abducted, pain w opp/abd


I&D across thenar crease and dorsal webspace


Define boundaries of midpalm space deep infection, symptoms/signs and treatment

MIDPALM - deep to flexors

Floor - Volar IO and MC 3,4,5

Roof - flexor sheaths 3,4,5 and palmar aponeurosis

Radial - vertical septum at D3 MC

Ulnar - hypothenar septum at D5 MC

Finding - loss of palmar concavity


I&D with incisoin from D3 webspace to pisiform


Define boudaries of Paronas space, findings and Treatment

  • volar wrist b/w PQ and long flexors
  • communicates w radial and ulnar bursa - horseshoe abscess- 
  • proximal extend to FDS insertion


What are complications of a hand infection


  • skin slough
  • extension to adjacent structures - OM, SA, tendon rupture, vessel thrombosis
  • amputation


  • recurrence
  • stiffness
  • degenrative arthritis


What is your management of a felon

= subcutaneous abscess of the finger pulp

Compx: OM, skin/pulp necrosis

Tx - I&D - incise on non-dominent side, break apart septae, keep intact flexor sheath, Abx, pack tid

--> can also consider longitudinal incision over most pointing aspect of felon


What is your management of a herpetic whitlow

= vesicles 2' to HSV1 (oral) HSV2 (genital)

Dx: Tzank smear of vesicle media or IF anti-HSV Ab

Tx: no I&D, dry gauze, topicla pancyclovir if immunocompromised, acyclovir if prodrome


What is your DDX of acute suppurative flexor tenosynovitis

  • gout/psudogout
  • inflammatory tenosynovitia
  • herpetic whitlow
  • felon
  • abscess


What is your management of acute flexor tenosynovitis suppurativa


  • IV abx, splint elevate observe and reqeunt reassessment


  • Catheter irrigation - incise prox to A1 distal to A4, irrigate w tid dressing change
  • ABX: ???
  • Early ROM


What is your management of a dog/cat bite



Rabies immunization


copious irrigation

delayed 1 wound healing

Xray to r/o FB

Abx: amox-clav (clavulin) OR if pen allergy, clindamycin + septra


What bacteria are associated w dog and cat bites?


  • s. aureus, s. viridans
  • bacteroides
  • pasteurella multicoda GNB
  • capnocytphaga canimorsus


- Pasteurella multicoda most common

plus similar to above

- cat scratch - rochalimaea henselea


What is your management of a human bite/fight bite




Xray for air in jt/FB

Clavulin OR if pen allergy, clindamycin + septra

I&D if joint involved, packing, delayed extensor repair


* most common pathogens

  • aerobics: s. aureus, epidermidis, strep
  • anaerobic:  bacteroides, peptococcus, peptosctreptococcus, Eikenella corrodens GNR,


What is your management of a necrotizing fasccitis

  • ABCs, ICU consult
  • Culture wound/blood
  • CBC, lytes Cr, LFT, CK, INR/PTT, lactate
  • Or - debridement devitalized tissue, repeat OR 24-48hrs later
  • IV abx - vanco+piptazo+clinda. Use 900mg IV q8h clinda for anaerobe, 4mu q4h penicillin for GAS


What are complications of septic arthritis

  • Stiffness, adhesions
  • OM
  • degenerative arthritis
  • boutonniere, mallet (pus erodes dorsally)
  • amputation


What will you send from sample for chronic wound to determine etiology

  • 1/2 in formalin (histo)
  • 1/2 not in formalin for 8pack micro diagnostic work-up:


  • ​Smears and stains:
    • Gram stain
    • AFB (ziehl neelsen)
    • Fungal stain (KOH)
  • Culture and sensitivity
    • aerobic
    • anaerobic
    • tuberculous mycobacteria at 37'
    • non-tuberculous mycobacteria at 30' (M.marinum) and at 42 (M.xenopi)
    • Mycotic culture media (Sabouraud dextrose agar) for sporotrichosis



What is your management of cat scatch disease?

  • Bartonella
  • Inoculation 1-3wks
  • lymphangitis, regional LAD
  • Self limiting


What is your management of Actinomycosis?

  • Actinomycosis Israelii
  • H&N, oral lesion ->abscess, + sinuses +sulfur yellow granules expressed, INVASIVE
  • Biopsy, Penicillin 6-12mths


What is your management of Tularemia?

  • Francisella Tularensis
  • Hx of animal bite non responisve to regular treatment w clavulin - >papule to ulceration/necrosis/lymphangitis
  • Tx: streptomycin/gentamycin


What necrotizing infection occurs from seawater contact/contamination?

  • Vibrio vulnificans -> necrotizing soft tissue infection - GN anaerobic rod
  • Tx: surgical debridement, +/- fasciotomies, DOXYCYCLINE


What is your treatment of onychomycosis?

  • Tinea infection - Trichophytan
  • nail thickening/seperation - occurs in DM/immunosuppressed/scleroderma
  • Dx: KOH of scrapings
  • Tx: antifungals topical, removal nail if persistent


What is your differential of a ulcerated verrucous nodule with lymphangitis wks-mths post injury, Hx of farming/gardening?


  • nocardiosis (dirt/soil)
  • tularemia  (animla contact)
  • atypical mycobacteria 
  • sporotrichosis schenckii (gardening)




What is your management of sporotrichosis?

  • sporothrix schenkii (fungal)
  • ulcerated raised verrucous nodule with lymphangitis, wks to months post injury while gardening
  • Dx: culture in Sabourard media
  • Tx: I&D of abscess if present, + amphotericin or itraconazole


What is your management of aspergillosis

  • Aspergillosis funigatis (hyphae)
  • necrotizing ulcer - usually at IV site - in immunocomp.
  • DDx nocardia, mucor
  • Dx: KOH prep
  • Tx - debridement w clear margins and amphotericin B


What is your management of mucormycosis

  • Mucorales rhizopus/rhizomucor
    • Triad: DM, gangrene, thrombosis + black discharge
  • Dx: biopsy
  • Tx:debridement + IV amphotericin