What is the recommended treatment for a patient with an ingrown toenail, considering potential complications and underlying conditions such as diabetes?

Ingrown Toenail Treatment

For diabetic patients with ingrown toenails, start with professional nail care including proper trimming and debridement, but if infection is present, obtain cultures and initiate antibiotics immediately; for non-diabetic patients, begin with conservative measures like gutter splinting or cotton placement, and reserve partial nail avulsion with phenolization for recurrent or severe cases. 1, 2

Risk Stratification and Initial Assessment

For Diabetic Patients

• Immediately evaluate diabetic foot risk category using IWGDF criteria to determine treatment urgency and follow-up frequency. 1
• Check specifically for peripheral neuropathy using 10g Semmes-Weinstein monofilament, assess pedal pulses for peripheral arterial disease, and examine for foot deformities. 1, 3
• Look for infection signs: erythema, pain, swelling, and purulence—these require urgent intervention. 1
• Never allow diabetic patients to self-treat, as neuropathy prevents them from recognizing worsening infection. 1

For Non-Diabetic Patients

• Assess severity: mild (pain and inflammation without infection), moderate (localized cellulitis), or severe (abscess formation or extensive infection). 4
• Identify contributing factors: improper nail trimming, tight footwear, hyperhidrosis, onychomycosis, or trauma. 2, 4

Treatment Algorithm

Conservative Treatment (First-Line for Mild-Moderate Cases)

For diabetic patients:

• Professional nail care by trained healthcare professionals only—trim the ingrown portion straight across, remove excess callus, and carefully debride the nail border. 1, 5
• Apply gutter splinting to separate the nail edge from the lateral fold for immediate pain relief. 4
• Consider nail bracing techniques or orthotic interventions for symptom relief without surgery. 1
• Prescribe extra-depth shoes with wide toe-box if toe deformities are present. 5, 3
• Schedule follow-up every 1-3 months for high-risk patients or every 3-6 months for moderate-risk patients. 1, 5

For non-diabetic patients:

• Soak the foot in warm, soapy water or Epsom salt solution. 2, 6
• Place cotton wisps or dental floss under the ingrown nail edge to lift it away from the lateral fold. 2, 4
• Apply gutter splinting for immediate pain relief—this is highly effective for mild to moderate cases. 4
• Consider cotton nail cast made with cotton and cyanoacrylate adhesive, or resin splint application (8.2% recurrence rate with average 9.3 months application). 4, 7
• Apply mid- to high-potency topical steroid after soaking to reduce inflammation. 4
• Correct inappropriate footwear and manage hyperhidrosis or onychomycosis if present. 4

Surgical Treatment (For Recurrent or Severe Cases)

For diabetic patients with failed conservative treatment:

• Digital flexor tenotomy is the preferred surgical intervention for diabetic patients with flexible hammertoes and distal toe ulcers or pre-ulcerative signs, achieving 92-100% healing rates in 21-40 days with 0-20% recurrence over 11-36 months. 5, 3
• Consider partial nail avulsion for recurrent ingrown nails without toe deformity. 1
• Always assess vascular status before any surgical intervention, as poor circulation impairs healing and increases infection risk. 1
• Post-operative infection risk is 9.5% in diabetic neuropathy patients, requiring careful patient selection. 5, 3

For non-diabetic patients:

• Partial nail avulsion combined with phenolization is the most effective surgical approach, superior to surgical excision alone in preventing symptomatic recurrence, though with slightly increased postoperative infection risk. 2
• Perform partial avulsion of the lateral edge of the nail plate followed by chemical matricectomy with phenol (88% phenol applied for 1-3 minutes). 2, 4
• Alternative matricectomy methods include electrocautery, radiofrequency ablation, or carbon dioxide laser ablation. 8, 2
• Complete nail excision (Zadik's procedure) is reserved for severe, recurrent cases involving the entire nail. 8
• Oral antibiotics before or after phenolization do not improve outcomes and should not be routinely prescribed. 2

Infection Management

For infected ingrown toenails in diabetic patients:

• Obtain appropriate cultures before starting antibiotics. 1
• Use broader spectrum coverage and longer duration for moderate infections. 1
• Never delay treatment, as infections can rapidly progress to serious complications in diabetic patients. 1

For infected ingrown toenails in non-diabetic patients:

• If inflammation and localized cellulitis do not resolve rapidly with soaking, proceed to surgical intervention. 6
• Antibiotics alone without addressing the mechanical problem are insufficient. 2

Prevention and Patient Education

• Educate patients to trim nails straight across and not too short—this is the most important preventive measure. 1, 4
• Advise against barefoot walking and wearing tight or inappropriate footwear. 1, 4
• Instruct diabetic patients to inspect feet daily and seek prompt medical attention if problems develop. 1, 5
• Manage contributing factors: hyperhidrosis, onychomycosis, and proper footwear selection. 4
• Be vigilant for fungal infections that often coexist with ingrown nails in diabetic patients. 1

Critical Pitfalls to Avoid

• Never allow diabetic patients with neuropathy to perform self-treatment or use chemical agents. 1
• Do not use conventional or standard therapeutic footwear for diabetic patients with active ulcers—these do not provide adequate offloading. 9
• Avoid delaying surgical intervention in recurrent cases, as repeated conservative treatments increase infection risk and patient morbidity. 4
• Do not prescribe prophylactic antibiotics with phenolization, as they provide no benefit. 2