What is the best treatment approach for a patient with large toe calluses, particularly considering the need for careful management due to potential underlying conditions like diabetes?

Treatment of Large Toe Calluses

For large toe calluses, begin with professional debridement by a trained foot care specialist combined with topical urea 40% cream applied twice daily, while simultaneously addressing the underlying mechanical cause through properly fitted therapeutic footwear with custom insoles or toe orthoses. 1, 2

Initial Assessment and Risk Stratification

Before treating toe calluses, determine if the patient has diabetes or peripheral neuropathy, as this fundamentally changes management:

• Check for loss of protective sensation using a 10g Semmes-Weinstein monofilament 3
• Assess pedal pulses to rule out peripheral arterial disease 1, 3
• Examine for hammertoe deformity, which creates abnormal pressure points leading to callus formation 3, 4

If diabetes with neuropathy or peripheral arterial disease is present, these calluses are pre-ulcerative lesions requiring immediate intervention to prevent ulceration. 3, 4

Conservative Treatment (First-Line for All Patients)

Professional Debridement

• Schedule regular professional callus removal every 1-3 months by a trained foot care specialist, not self-treatment 1, 3, 4
• Scalpel debridement by a specialist provides immediate and significant improvement in skin quality, pain, and function 5
• Never use chemical agents or plasters for self-removal of calluses, as this increases infection risk 1

Topical Keratolytic Therapy

• Apply urea 40% cream to affected areas twice daily until completely absorbed 2
• Urea dissolves the intracellular matrix, loosening the horny layer and promoting shedding of hyperkeratotic skin 2
• Alternative: topical salicylic acid preparations have short-term benefits for callus reduction 6

Footwear Modifications (Critical for Long-Term Success)

• Prescribe extra-depth shoes with wide toe-box (1-2 cm longer than foot, internal width equal to foot width at metatarsophalangeal joints) 1, 3
• Provide custom-made insoles or toe orthoses when foot deformity or pre-ulcerative signs are present to redistribute pressure 1, 3
• Rigid orthotic devices significantly reduce callus grade over 12 months by lowering abnormal foot pressures 7
• Instruct patients never to walk barefoot, in socks only, or in thin-soled slippers 1

Patient Education

• Daily foot inspection for new lesions or changes 1, 3
• Proper nail trimming (straight across) 1
• Use lubricating creams for dry skin, but not between toes 1
• Daily sock changes with seams inside-out or seamless 1

When Conservative Treatment Fails

Surgical Intervention for Diabetic Patients with Hammertoes

If calluses persist despite 3 months of conservative treatment in diabetic patients with hammertoes and pre-ulcerative signs, proceed directly to digital flexor tenotomy. 1, 3, 4

Evidence for Digital Flexor Tenotomy:

• Healing rates of 92-100% achieved in 21-40 days with low complication rates 3, 4
• 0% ulcer occurrence in 58 patients with pre-ulcerative signs over 11-31 months follow-up 1, 4
• Recurrence rates of 0-20% over 11-36 months in 231 treated patients 1
• Performed as outpatient procedure without subsequent immobilization 1, 3

Important Caveats:

• Post-operative infection risk is 9.5% in diabetic neuropathy patients, requiring careful patient selection 3, 4
• Discuss potential adverse effects including transfer lesions and non-healing in patients with poor arterial supply 1
• Only proceed after full evaluation by appropriately trained healthcare professional 1

Common Pitfalls to Avoid

• Do not treat calluses in isolation without addressing underlying biomechanical abnormalities—this leads to rapid recurrence 8
• Avoid chemical corn removers in diabetic patients due to infection risk 1
• Do not delay surgical referral in diabetic patients with persistent pre-ulcerative calluses after conservative treatment fails, as this increases ulceration risk 3, 4
• Ensure proper footwear fit is verified with patient standing at end of day when feet are most swollen 1

Follow-Up Schedule

• High-risk diabetic patients: Integrated foot care every 1-3 months including professional treatment, footwear assessment, and education 3, 4
• Non-diabetic patients: Follow-up based on symptom resolution, typically reassess at 3 weeks after initial treatment 5
• Monitor for recurrence and adjust orthotic devices as needed 7