What is the appropriate management for a patient with a complaint of feeling like they are walking on a pebble, possibly due to a plantar wart or callus, and who may have a history of conditions like diabetes?

Management of "Walking on a Pebble" Sensation

The sensation of walking on a pebble most commonly indicates either a plantar callus or a plantar wart (verruca), and immediate management requires distinguishing between these two entities through careful examination, followed by appropriate debridement and pressure offloading. 1, 2

Initial Diagnostic Approach

Key Examination Findings

Differentiate callus from plantar wart by paring down the hyperkeratotic tissue:

• For plantar warts: Multiple "seeds" (thrombosed capillaries) will appear in the dermis after debridement, with pinhead-sized bleeding points within and surrounding the lesion 1, 2
• For calluses: Smooth surface after paring without punctate bleeding, typically located under metatarsal heads or over bony prominences 3, 4

Critical assessment if diabetes is present or suspected:

• Perform monofilament testing (10-g Semmes-Weinstein) to assess for loss of protective sensation 3
• Palpate pedal pulses and assess for peripheral arterial disease 3
• Inspect for erythema, warmth, or signs of impending tissue breakdown around the lesion 3

Management Based on Diagnosis

If Plantar Callus is Confirmed

Immediate treatment:

• Debride the callus with a scalpel (performed by trained foot care specialist) 3
• This must be repeated until the callus resolves and does not recur 3

Pressure redistribution (essential to prevent recurrence):

• Prescribe well-fitted walking shoes or athletic shoes that cushion the feet and redistribute plantar pressure 3
• If bony deformities present (hammertoes, prominent metatarsal heads, bunions), prescribe extra wide/deep therapeutic shoes 3
• Consider rigid orthotic devices, which have demonstrated significant reduction in callus grade over 12 months 5

Critical instruction:

• Patient must never walk barefoot, in socks only, or in thin-soled slippers at home or outside 3, 6

If Plantar Wart is Confirmed

First-line treatment:

• Apply 40% salicylic acid patch system to the debrided site every 48 hours until healing occurs 1
• Alternative options include topical 5-fluorouracil, cryotherapy, or surgical excision if refractory 2

Important caveat in diabetic patients:

• Verrucae may mimic treatment-refractory hyperkeratosis in diabetic foot lesions 2
• If lesion appears refractory to standard callus treatment, perform dermoscopy and punch biopsy to confirm diagnosis 2
• Treatment duration may be prolonged (mean 9.4 months) and requires combination with local pressure offloading 2

Special Considerations for Diabetic Patients

If patient has diabetes, this is a high-risk situation requiring:

• Comprehensive foot examination including assessment of protective sensation, foot structure, vascular status, and skin integrity 3
• Visual inspection at every healthcare visit if neuropathy is present 3
• Referral to multidisciplinary foot care team if history of prior ulceration, amputation, or loss of protective sensation 3

Pre-ulcerative signs requiring immediate action:

• Presence of erythema, warmth, or hemorrhage under the callus indicates impending tissue breakdown 3
• These signs require more frequent evaluation and aggressive pressure offloading 3

Common Pitfalls to Avoid

• Do not assume all hyperkeratotic lesions are simple calluses - always pare down to differentiate from warts, especially in diabetic patients where warts may be more common than generally recognized 2
• Do not treat and release without addressing underlying pressure - calluses will recur without proper footwear and pressure redistribution 3, 5
• Do not perform aggressive surgical debridement of warts in ischemic feet - assess vascular status first 3
• Do not rely on patient self-management alone - this requires professional foot care specialist involvement for debridement 3

Patient Education Requirements

• Daily foot inspection for new lesions or changes 3
• Proper footwear at all times (never barefoot or in thin slippers) 3, 6
• Immediate reporting of any warmth, redness, or drainage 3
• Understanding that adherence to offloading footwear is critical for resolution 6