How should I treat a laceration on the right finger at the interphalangeal joint that is red and swollen?

Management of Infected Laceration at the Interphalangeal Joint

This infected laceration over the interphalangeal joint requires immediate wound care with sterile saline irrigation, elevation, empirical antibiotics, and close monitoring—do not close the wound, and ensure tetanus prophylaxis is current. 1

Immediate Wound Management

Infected wounds at the interphalangeal joint must not be sutured or closed. 1 The presence of redness and swelling indicates active infection, making primary closure contraindicated as it traps bacteria and increases risk of serious complications including septic arthritis and osteomyelitis. 1

Wound Care Protocol

• Irrigate the wound copiously with sterile normal saline only—no iodine or antibiotic-containing solutions are needed. 1
• Remove only superficial debris; avoid aggressive debridement as this enlarges the wound and impairs eventual closure. 1
• Consider wound approximation with Steri-Strips only after infection resolves, followed by delayed primary or secondary closure. 1
• Apply a sterile bandage after topical antibiotic ointment (bacitracin applied 1-3 times daily to an area equal to a fingertip). 2

Elevation and Immobilization

Elevate the injured finger continuously during the first few days, especially given the swelling, as this accelerates healing. 1 Use a sling for outpatient management or a tubular stockinet with IV pole if hospitalized. 1

Empirical Antibiotic Therapy

Outpatient Oral Regimen (First-Line)

Amoxicillin-clavulanate is the recommended first-line oral antibiotic for infected hand wounds. 1 This covers the most common pathogens including Staphylococcus aureus, Streptococcus species, and anaerobes.

Alternative Oral Options

• Doxycycline as monotherapy. 1
• Penicillin VK plus dicloxacillin combination. 1
• Fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin) PLUS metronidazole or clindamycin for anaerobic coverage. 1

Antibiotics to AVOID

Do not use cephalexin, dicloxacillin alone, erythromycin, or clindamycin alone—these have poor activity against common pathogens in hand wounds. 1

Intravenous Options (If Hospitalization Required)

• Ampicillin-sulbactam, piperacillin-tazobactam, cefoxitin, or carbapenems (ertapenem, imipenem, meropenem). 1
• Consider a single initial parenteral dose before transitioning to oral therapy. 1

Critical Warning Signs Requiring Urgent Evaluation

Pain disproportionate to the injury severity, especially near a joint, suggests periosteal penetration or septic arthritis. 1 Hand wounds are inherently more serious than wounds to fleshy body parts due to proximity of critical structures. 1

Indications for Hospitalization

• Progression of infection despite appropriate oral antibiotics and wound care. 1
• Signs of septic arthritis: severe pain with passive motion, joint effusion, inability to flex/extend the joint. 1
• Signs of osteomyelitis: persistent deep bone pain, systemic symptoms. 1
• Tendon involvement: inability to actively flex or extend the finger. 1

Imaging Considerations

Obtain plain radiographs (PA, lateral, and oblique views) to rule out:

• Foreign body (glass, wood, metal fragments). 1
• Fracture or avulsion injury at the joint. 1, 3
• Gas in soft tissues suggesting necrotizing infection. 1

MRI without contrast is ideal if tendon injury, ligament tear, or occult fracture is suspected based on mechanism or physical exam findings. 1, 4

Tetanus Prophylaxis

Administer tetanus toxoid (0.5 mL intramuscularly) if status is outdated or unknown. 1

Follow-Up Protocol

Mandatory follow-up within 24 hours either by phone or office visit to assess response to treatment. 1 If swelling, redness, or pain worsens, immediate re-evaluation is required. 1

Duration of Antibiotic Therapy

• Uncomplicated soft tissue infection: 5-7 days. 1
• Septic arthritis: 3-4 weeks. 1
• Osteomyelitis: 4-6 weeks. 1

Common Pitfalls to Avoid

• Never close an infected wound—this is the most critical error and can lead to abscess formation, septic arthritis, or osteomyelitis. 1
• Do not use first-generation cephalosporins or macrolides alone—inadequate coverage. 1
• Do not delay imaging if foreign body or fracture is suspected—retained foreign bodies perpetuate infection. 1
• Do not underestimate hand infections—they can rapidly progress to permanent disability if undertreated. 1