What is the protocol for draining a felon?

Protocol for Draining a Felon

Surgical drainage is the definitive treatment for an established felon abscess, performed through a longitudinal volar incision if superficial or a unilateral longitudinal incision if deep, with careful attention not to extend past the distal interphalangeal (DIP) joint. 1

Indications for Drainage

• Drain all established abscesses with fluctuance, pointing, or visible pus in the pulp space 2, 1
• Early felons without abscess formation may be managed with antibiotics, elevation, warm soaks, and splinting in the position of function 2
• Once an abscess develops, surgical drainage is required to prevent digital compartment syndrome and tissue necrosis 1

Pre-Procedure Preparation

• Perform digital block anesthesia using local anesthetic (avoid excessive volumes which can increase compartment pressure) 2
• Apply a tourniquet at the base of the finger for hemostasis and visualization 1
• Use sterile technique with appropriate skin preparation 2

Surgical Technique

Preferred Incision Approaches:

For superficial felons:

• Longitudinal volar incision over the point of maximal fluctuance, staying midline and not extending past the DIP joint crease 1

For deeper felons:

• Unilateral longitudinal incision along the lateral aspect of the digit, avoiding the neurovascular bundle 1
• This approach provides better access to the multiple fibrous septae in the pulp space 3

Critical Technical Points:

• Break up all fibrous septae within the pulp space using a blunt instrument to ensure complete drainage 3, 1
• Irrigate the cavity copiously with sterile saline 2
• Do NOT extend the incision past the DIP joint to avoid damaging the flexor tendon sheath 1
• Avoid "fish mouth" or transverse incisions across the fingertip as these risk neurovascular injury and unstable scars 1

Post-Drainage Management

Wound Care:

• Pack loosely with iodoform gauze or leave open to drain 2, 1
• Apply bulky dressing and splint in position of function 2
• Elevate the hand above heart level 2
• Remove packing at 24-48 hours and begin warm soaks 2, 1

Antibiotics:

Antibiotics are NOT necessary after adequate surgical drainage in uncomplicated cases 4

• A prospective study of 46 patients showed 98% healing without postoperative antibiotics after complete surgical excision 4
• The single failure was attributed to inadequate drainage, not lack of antibiotics 4

Reserve antibiotics for:

• Immunocompromised patients (diabetic, HIV, transplant recipients) 4
• Patients with cardiac valve prostheses 4
• Signs of spreading infection (lymphangitis, cellulitis extending beyond the digit) 2, 4
• Associated complications (osteomyelitis, septic arthritis, flexor tenosynovitis) 4

If antibiotics are indicated:

• Target Staphylococcus aureus (most common pathogen) 2, 3
• Use antistaphylococcal coverage (cephalexin, dicloxacillin, or clindamycin) 2
• Consider MRSA coverage if risk factors present 2

Follow-Up

• Reassess at 24-48 hours for wound check and packing removal 2, 1
• Evaluate at days 7,14, and 21 for complete healing 4
• Begin early range-of-motion exercises once acute infection resolves to prevent stiffness 3

Common Pitfalls to Avoid

• Inadequate drainage is the primary cause of treatment failure—ensure all septae are broken and all pus evacuated 4
• Incisions extending past the DIP joint risk flexor tenosynovitis 1
• Transverse or "fish mouth" incisions cause neurovascular injury and poor cosmetic outcomes 1
• Empiric antibiotic use without drainage will fail once abscess forms 2, 4
• Delaying surgical treatment increases risk of osteomyelitis, septic arthritis, and permanent tissue damage 5, 2