Tracey Vlahovic DPM writes: Often my coworkers will have me perform a “drive-by consult” on their patients to determine if a plantar lesion is a wart or a callus. We have all learned the traditional squeeze maneuver to determine if pain is present on direct pressure (callus) or pain when laterally squeezing the lesion (wart).1 We have all looked for the visual signs: lack of dermatoglyphics running through the lesion, presence of black dots (thrombosed capillaries), scalloped border, pinpoint bleeding upon debridement, the anatomic location of a traditional callus, etc.
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When dermoscopy can be helpful in differentiating between a wart and a callus