How should an infected ingrown toenail that was treated with a phenol matrixectomy five months ago be managed?

Management of Infected Ingrown Toenail After Failed Phenol Matrixectomy

For an infected ingrown toenail that recurred 5 months after phenol matrixectomy, you should first control the active infection with oral antibiotics and local wound care, then perform repeat partial nail avulsion with phenol matricectomy once the infection has resolved. 1, 2

Immediate Infection Management

Antibiotic Therapy

• Culture any purulent drainage before initiating antibiotics to guide therapy if initial treatment fails 3
• Start empiric oral antibiotics covering Staphylococcus aureus and streptococci (the most common pathogens in acute paronychia) 3
• Consider doxycycline 100 mg twice daily for recurrent or treatment-refractory paronychia 3

Local Wound Care

• Apply topical 2% povidone-iodine daily to the infected nail fold 3
• Perform dilute vinegar soaks (50:50 dilution) to the nail folds twice daily for 10-15 minutes to reduce bacterial load 3
• Avoid topical corticosteroids during active purulent infection as they can worsen bacterial proliferation 3
• If granulation tissue is present, apply silver nitrate or perform scoop shave removal with hyfrecation 3

Temporary Mechanical Relief

• Insert dental floss under the ingrown nail edge to separate it from the underlying inflamed tissue 3
• Alternatively, use flexible tube splinting by placing a plastic tube with a lengthwise incision over the lateral nail edge 3
• Tape the nail fold away from the nail plate to reduce pressure and allow drainage 3

Definitive Surgical Management After Infection Resolution

Timing of Repeat Procedure

• Wait until active infection has completely resolved before performing repeat phenol matrixectomy to minimize risk of osteomyelitis and ensure optimal healing 3, 1
• Active infection increases the risk of deeper tissue involvement and surgical complications 3

Repeat Phenol Matrixectomy Technique

• Perform proximolateral partial nail avulsion removing the ingrown lateral nail plate segment 1, 2
• Apply 88% phenol to the exposed lateral nail matrix for 45 seconds, which achieves recurrence rates of only 1.87% at 6 months 2
• The 45-second application time is critical—shorter durations may lead to inadequate matrix destruction and recurrence 2
• Use multiple applications (typically 2-3 cycles of 45 seconds each) to ensure complete matrix ablation 1, 4
• Neutralize phenol with isopropyl alcohol after each application 1, 5

Why the Initial Procedure Failed

The most common causes of recurrence after phenol matrixectomy include:

• Inadequate phenol contact time with the nail matrix (less than 45 seconds per application) 2
• Incomplete removal of the lateral nail plate, leaving residual nail spicules 2, 5
• Insufficient phenol penetration into the matrix horn (the most proximal portion) 1, 5
• Technical error in identifying and treating the entire lateral matrix 1, 4

Expected Outcomes with Repeat Procedure

• Success rates for repeat phenol matrixectomy exceed 99% with proper technique 1, 4, 5
• Recurrence rates range from 0.75% at 3 months to 2.96% at 12+ months when performed correctly 2, 4
• The medial nail fold has higher recurrence rates than the lateral fold, so extra attention is needed if that side is affected 2

Post-Procedure Management

Wound Care

• Expect postoperative drainage for 15-18 days, which is normal after phenol application 6, 5
• Postoperative pain typically lasts 8-16 days 6, 5
• Complete tissue normalization occurs within 15-16 days 6
• Full wound healing requires weekly monitoring until complete epithelialization 1

Common Pitfalls to Avoid

• Do not perform the repeat procedure during active infection—this dramatically increases complication risk including osteomyelitis 3
• Do not use inadequate phenol contact time (less than 45 seconds)—this is the primary cause of recurrence 2
• Do not fail to treat the entire lateral matrix including the proximal horn—incomplete treatment guarantees recurrence 1, 5

Alternative Consideration: Surgical Excision

If repeat phenol matrixectomy fails or if there is concern for underlying osteomyelitis:

• Consider formal surgical excision of the lateral nail matrix with primary closure 3
• Obtain bone specimen for culture and histopathology if osteomyelitis is suspected 3
• This approach has higher morbidity but may be necessary for complex recurrent cases 1, 4