What is the first‑line management for a plantar callus in an adult, and how should treatment be modified for patients with diabetes, peripheral neuropathy, peripheral arterial disease, or signs of infection?

Management of Plantar Callus

For adults without diabetes or vascular disease, professional scalpel debridement by a trained healthcare provider combined with appropriate footwear is the definitive first-line treatment for plantar callus. 1

First-Line Management for Adults (General Population)

Professional Debridement

• Sharp scalpel debridement is the gold standard treatment that must be performed by a trained healthcare professional to remove all callus tissue, as this reduces plantar pressure by up to 58% and prevents ulceration. 1, 2
• Debridement should be repeated every 1-3 months for high-risk patients and every 3-6 months for moderate-risk patients based on callus recurrence patterns. 1
• The mechanical impact is substantial: a single callus can generate 18,600 kg of excess plantar pressure per day in an average person taking 10,000 steps. 2

Addressing Mechanical Causes

• Prescribe custom-made footwear, custom-made insoles, or orthotic devices for patients with foot deformities or recurrent calluses to redistribute pressure and prevent reformation. 1, 3
• Toe silicone devices and semi-rigid orthotic devices are effective for reducing pressure on specific areas. 1, 3

Prevention Measures

• Apply emollients daily to maintain skin elasticity, but never between toes to avoid maceration. 1
• Instruct patients never to walk barefoot, in socks only, or in thin-soled slippers, whether at home or outside. 1, 3
• Daily foot inspection to identify early callus development before complications arise. 1

Critical Safety Points

• Never allow patients to self-treat with chemical corn removers or plasters, as this dramatically increases infection and ulceration risk. 1
• All debridement must be performed by trained professionals—home cutting of calluses is contraindicated. 1

Modified Management for Patients with Diabetes

Immediate Treatment Approach

• In diabetic patients, calluses are pre-ulcerative lesions requiring immediate treatment by an appropriately trained healthcare professional to prevent foot ulceration. 3, 1
• Professional callus removal must be performed more frequently (every 1-3 months) as part of integrated foot care that includes appropriate footwear and structured education. 1
• Callus removal reduces plantar pressure, which is an important risk factor for ulceration in the neuropathic diabetic foot. 3

Enhanced Monitoring

• More conservative debridement approach is required due to higher complication risk in diabetic patients. 1
• Treat any pre-ulcerative signs (blisters, fissures, hemorrhage under callus) immediately, as these are strong predictors of future ulceration. 3

Footwear Requirements

• Prescribe therapeutic footwear with demonstrated plantar pressure-relieving effect (30% relief compared with standard therapeutic footwear) to prevent recurrent plantar ulceration. 3
• When foot deformity or pre-ulcerative signs are present, prescribe therapeutic shoes, custom-made insoles, or toe orthosis. 3

Surgical Options for Refractory Cases

• Consider digital flexor tenotomy for calluses associated with hammertoes and pre-ulcerative toe lesions when conservative treatment fails. 3, 1
• Consider Achilles tendon lengthening, joint arthroplasty, or metatarsal head resection for recurrent plantar forefoot calluses unresponsive to conservative management. 3, 1

Modified Management for Peripheral Neuropathy

Risk Assessment

• Loss of protective sensation dramatically increases ulceration risk when combined with callus formation, as patients cannot perceive repetitive trauma. 3, 4
• Motor neuropathy leads to foot deformity and sensory neuropathy causes persistent abnormal pressure, resulting in hyperkeratinization that predisposes to ulceration. 4

Treatment Modifications

• More aggressive and frequent callus removal is recommended in patients with neuropathy, as they lack the protective feedback mechanism to avoid trauma. 2
• Educate patients to substitute other sensory modalities (hand palpation, visual inspection with mirror) for daily foot surveillance. 3
• Ensure patients understand they must never walk barefoot due to inability to perceive injury. 3

Modified Management for Peripheral Arterial Disease

Vascular Assessment First

• Assess vascular status immediately before aggressive debridement, as inadequate arterial perfusion may prevent wound healing and increase complication risk. 5
• Initial screening should include history for claudication and assessment of pedal pulses; consider ankle-brachial index if pulses are diminished or absent. 3
• A toe-brachial index >0.7 makes significant PAD less likely; values <0.7 warrant vascular consultation. 3

Conservative Debridement Approach

• Use more conservative debridement technique in patients with PAD due to impaired healing capacity and higher risk of complications. 1
• Avoid aggressive debridement if ankle pressure <50 mmHg or toe pressure <30 mmHg without first considering revascularization. 3

Revascularization Considerations

• Consider vascular consultation for revascularization if healing is impaired despite appropriate treatment, particularly if ankle-brachial index <0.6 or toe pressure <50 mmHg. 3

Management When Infection is Present

Urgent Intervention Required

• Perform urgent surgical debridement of all necrotic tissue, as this is essential for infection control and allowing antibiotic penetration. 5
• For moderate to severe infections, surgical consultation is mandatory to assess for deep abscess, extensive necrosis, or bone/joint involvement. 5

Diagnostic Workup

• Rule out osteomyelitis urgently with plain radiographs or MRI, as bone involvement requires 4-6 weeks of antibiotics and dramatically changes management. 5
• Obtain bone cultures if osteomyelitis is suspected, as culture-directed antibiotic therapy significantly improves resolution rates. 5

Offloading Modifications

• Use removable offloading devices rather than non-removable devices when moderate-to-severe infection is present to allow frequent wound inspection and dressing changes. 3, 6
• Prioritize wound access over rigid immobilization in infected wounds. 6

Antibiotic Therapy

• Initiate empirical broad-spectrum parenteral antibiotics for deep infections, targeting Gram-positive and Gram-negative bacteria including anaerobes. 3
• Switch to broader spectrum coverage (imipenem-cilastatin or vancomycin plus ceftazidime with or without metronidazole) for severe infections not responding to initial therapy. 5

Common Pitfalls to Avoid

• Never delay callus treatment in diabetic patients, as calluses are pre-ulcerative lesions that predict future ulceration. 3
• Avoid applying moisturizers between toes, as this increases maceration risk. 1
• Do not prescribe conventional or standard therapeutic shoes to heal a plantar foot ulcer—these are inadequate for active ulceration. 3
• Never perform aggressive debridement in ischemic feet without signs of infection, as this can precipitate tissue loss. 3