Paronychia (Nailfold Infection)Paronychial infections are common and account for 10 to 20 percent of hand infections.
What Causes Hand Infections?
- Hangnail, nail biting and frequent exposure to moisture are common contributing factors.
- Dry cracked skin due to cold dry weather or detergents also play a part.
- Gently probing the involved nailfold usually provides adequate drainage.
- Daily soaks and oral antibiotics are recommended for several days.
Staphylococcus aureus is the usual organism. Pus under the nail plate requires removal of all or part of the nail plate.
Herpetic WhitlowHerpes simplex infection of the fingertip tissues can mimic paronychia.
SymptomsPain is usually severe and clear fluid filled vesicles follow the initial phase of swelling and redness. Viral cultures of the vesicle fluid confirm the diagnosis.
Treatment OptionsTreatment is non-operative unless there is a secondary infection. Antiviral drugs may shorten the several-day course of infection. Latent infection may result in several recurrences over a period of weeks to months.
FelonA felon is an abscess of the fingertip pad.
SymptomsMinimal trauma can provide an entry point for bacteria, usually staphylococcus aureus. Swelling, redness, and intense pain develop.
Treatment OptionsDrainage through a longitudinal incision over the point of maximal tenderness provides relief. The infection resolves promptly with drainage and appropriate antibiotics. Residual fingertip tenderness can be a problem.
Pyogenic Flexor TenosynovitisThe flexor tendon sheath is a closed space containing synovial fluid. Bacteria introduced by direct trauma, or rarely as blood born pathogens, flourish in this space. Kanavel's four classic signs below.
- fusiform digital swelling
- semiflexed digital posture
- pain with passive extension
- tenderness over the flexor tendon sheath
Treatment OptionsSurgical drainage and hospitalization are required. Treatment delays can result in loss of the flexor tendons or even the digit.
Bite Wound InfectionsAnimal and human bite wounds commonly occur on the hand. Deep penetration of a tooth covered with a mixed flora of organisms results in cellulitis and abscess formation.
Treatment OptionsInitial treatment should include irrigation and usually debridement of the puncture site. Even the tiny puncture wound from a cat’s tooth should be opened with a small stab wound. Antibiotics should be selected to cover both aerobic and anaerobic organisms. Amoxicillin/Clavulanate is recommended by many. Penicillin G and Cephalexinare are less costly. Daily wound checks are necessary and hospitalization of unreliable patients should be considered. Most clenched fist tooth puncture wounds should be explored in the operating room because the risk of infection in the metacarpophalangeal joint is very high.
Deep Space Infections of the HandThere are five potential deep spaces within the hand:
- the inter-digital webspace between the metacarpal heads
- the thenar space
- the hypothenar space, the mid palmar space deep to the flexor tendons
- the dorsal subaponeurotic space, deep to the extensor tendons
- Parona’s space in the distal forearms deep to the digital flexor tendons