Soft Tissue Infections

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Hand Infections

  • Infection BENEATH EPONYCHIAL FOLD, begins dorsal to nail and may spread superficially around the nail 
  • Most common pathogen – GPC, staph aureus
  • Treatment
    • Initially may involve just warm soaks, if abscess has developed will require drainage with the eponychial fold separated from nail, if abscess under nail must remove nail
  • Acute (usually bacterial) –> augmentin etc
  • Chronic (usually fungal) -> topical miconazole or terbinafin vs PO ketoconazole or fluconazole
    • If treatment fails then tx with marsupialization 


  • Presents with red, swollen, fluctuant fingertip 
  • Most common pathogen – GPC, staph aureus
  • tx: open longitudinally along point of maximum fluctuance, or use a lateral incision over mid axial line (ulnar for index, middle and ring, radial for small finger and thumb), debridement, soaks, antibiotics

Collar button abscess

  • Infection of the interdigital web space 
  • Presents with ABDUCTED digits and pain/swelling/erythema in web space
  • Tx with incision and drainage using longitudinal volar and dorsal incisions, don’t incise all the way through web space, avoid motor branch of median nerve to thenar muscles 

Flexor Tenosynovitis 

  • Kanavel’s signs: sausage swelling, tenderness along flexor sheath, flexed finger at rest, pain on passive extension
  • Operative irrigation/drainage of flexor sheath
    • Single incision
    • Double incision with angiocath flow through
    • May have to explore parona’s space (horseshoe shaped connection between the small finger and thumb sheaths)
  • Most common bacteria is staph aureus but may have others (frequently tested)
    • Marine exposure
      • Flexor Teno with Minimal symptoms -> Mycobacterium marinum
        • Tx with Clarithromycin
      • Flexor tenor with severe systemic symptoms, severe swelling, hemorrhagic bullae -> vibrio vulnificus (gram negative bacillus)
        • Tx with ceftriaxone, levofloxacin

Deep Space Infections:

  • Thenar Space:
    • Borders
      • Dorsal border – fascia of Adductor pollicus
      • Volar border – index flexor tendons
      • Ulnar – midpalmar septum of third MC
      • Radial – adductor pollicus insertion 
    • Will see palmar ABduction of the thumb
    • Pain exacerbated by passive adduction and opposition 
    • Severe infections – extend to first webspace and dorsoradial hand, “Dumbbell or pantaloon infection”
  • Midpalmar Space:
    • Boundaries – deep to flexor tendons of long-small, superficial to metacarpals/IOs
      • Radial border – septum of LF MC, Ulnar border – hypothenar muscles
    • “Loss of palmar concavity”
    • Typically spread from long/ring/or small finger flexor teno
    • May be significant DORSAL hand swelling
  • Hypothenar Space:
    • Less common infection
    • Radially hypothenar septum is border
    • Incision over hypothenar muscles 
  • Parona Space:
    • Boundaries – PQ, digital flexors, FPL, vertical band of facia radial to FCU
    • Contiguous with radial/ulnar bursa:
      • Can develop “horseshoe abscess” with infection spread from either

Herpetic Whitlow

  • HSV infection of the digits, may be seen in dentists or oral hygenists 
  • Treatment – Observe, clean BID to avoid bacterial superinfection, DO NOT unroof
  • Acyclovir vs valacyclovir if caught within the first 1-3 days

Septic arthritis & OM

  • Infection of the joint space that can lead to permanent damage caused by bacterial toxin destruction of cartilage, increased pressure decreases perfusion to joint 
  • Dx – PAIN AGGRAVATED BY JOINT MOTION, almost complete LOSS of motion 
    • Must aspirate joint to confirm infection – WBC >50, Glucose 40mg less than fasting blood, bacteria on Gm stain
  • Most common bacteria – S. Aureus, N. Gonorrhea, H. flu in kids 
  • Tx – Surgically decompressed urgently + Abx
  • Abx – First gen cephalosporin or clinda, N Gonnorrhea with IV Ceftriaxone

Most common bacteria:

    • Cat/dog = pasteurella
    • Flavobacterium = freshwater fish
    • Mycobacterium = bears and ferrets
    • Vibrio = shark bites
    • Humans = eikinella
  • Cat bites more often become infected and cause abscesses since they have teeth that penetrate instead of open up the skin –> for that reason typically I&D almost all cat bites
  • cat scratch fever (caused by bartonella)
    • axillary node swelling, bump at site of bite/scratch
    • —> NSAIDs, supportive treatment, time (up to 4 months)

Human bite (fight bite)

  • Most common is strep viridians > staph > bacteroides > eikenella but eikenella is the one we are tested on most frequently
  • Augmentin vs bactrim/clinda (if penicillin allergy)

Toxic shock syndrome

  • May be seen in rhinoplasty patients with prolonged nasal packing (prior question)
  • T>102, multisystem organ failure, rash, erythema extending away from surgical site
  • Caused by toxins produced by staph (exotoxin1) or strep bacteria (enterotoxin a/b/c)
  • Clindamycin inactivates the toxin + broad spectrum coverage for bacteria


  • T cell mediated hypersensitivity to a DRUG (antibiotics, anticonvulsants, NSAIDs)
  • Fever, painful vesiculobullous rash, mucosal involvement, full thickness necrosis, multi organ dysfunction
  • Supportive treatment in burn center


  • Nonpurulent necrotizing fungal infection, seen most commonly in diabetics
  • On stain will show right angle nonseptate branching hyphae
  • Aggressive debridement, strong antifungals

Necrotizing fascitis 

  • Rapidly progressing soft tissue infection that does progressess along fascial planes 
  • Polymycrobial (Strep pyogenes, ecoli, proteus, serratia, s aureus)
    • Excessive toxin production of strep
  • Erythema, bullae, sick as ****, clear grey dishwater fluid, crepitus
  • Worst prognostic indicator is delay in surgical intervention

Other pathologies

  • Originates from apocrine glands
  • Hurley scale
    • Stage I: separate abscesses which drain on their own
    • Stage II: multiple abscesses which scar and require drainage
    • Stage III: multiple scarring and tracking connected abscesses
  • Early, solitary, uncomplicated – excision, steroid injections
  • Widespread – antibiotics, hygeine, weight loss
  • Recurrent, debilitating – excision and closure versus skin graft versus healing by secondary intent
    • Commonly the answer on our inservice***

Pyoderma gangrenosum

  • Skin ulceration and breakdown which looks infectious, keeps getting worse when you try to treat it
  • Mediated by neutrophils, often seen with inflammatory bowel disease or inflammatory arthritis
  • Diagnosis: biopsy
  • Treatment: treat underlying disease, steroids

Follicular pyodermas

  • Infection of hair follicles
  • Includes: folliculitis, furuncles, carbuncles
  • Treatment: local I&D vs antibiotics, hygeine

Preoperative antibiotics indicated in…

    • surgeries >2h
    • any clean breast surgery
    • contaminated surgery of hand or face 
    • Gustillo III injuries (cephalosporin)
  • Ancef – 1g <80kg, 2g >80kg 40 min prior to incision
  • Vancomycin – 1-1.5g IV
  • Clindamycin (for penicillin/cephalosporin allergies) – 600-900mg IV

So you drop something

  • Bone – Decontaminate with betadine irrigation then saline rinse (triple antibiotic solution is off the market)
    • “for a brief time it came into contact with a non-sterile surface but was treated appropriately”
  • Anything other than bone – decontaminate thoroughly with chlorhexidine
  • Wound is now considered class 3 (contaminated)
    • Class 1 – clean – operative incision is made
    • Class 2 – clean contaminated – operative incision made, also involves respiratory/GI/genitourinary tracts
    • Class 3 – contaminated – operative incision with breach in sterile technique, or traumatic wound with outside contamination
    • Class 4 – infected – old surgical wounds with evidence of existing infection or old traumatic wounds with existing infection


  • Don’t forget a tetanus shot!
  • Tetracyclines are not for kids <8; and quinolones are not for kids <18
  • Clearly a skin infection from the water but no systemic illness = Mycobacterium
  • Leeches –> aeromonas –> ciprofloxacin, tetracycline, bactrim, 3rd gen cephalosporins
  • Cdiff –> flagyl for mild/moderate, PO vanc or fidaxomicin for severe
  • Cervical necrotizing fasciitis = Comes from pharyngitis
  • Diabetes + nasty necrotizing nonpurulent infection = Mucormycosis
  • If it sounds like nec fasc it probably is nec fasc
  • Immunosuppressed = Suspect TB (rice bodies, ziehl-neelsen stain, lowenstein jensen medium)
  • dental hygienist: herpetic whitlow
  • Nail biting/dishwashing: paronychia
  • XR, MRI is most sensitive for fluid collection
    • gas: gas gangrene/nec fasciae
    • periosteal reaction: osteomyelitis
  • MRSA De-Colonization
    • Only thing proven to decolonize is mupirocin ointment and chlorhexidine body wash x5 days

ACAPS Inservice 2013-2020
Plastic Surgery Emergencies

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