Ali is a 43-year-old business owner who presents with a five-year history of gradually enlarging, painless, symmetrical lesions on the dorsolateral aspect of both ankles.

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<p>Ali is a 43-year-old business owner who presents with a five-year history of gradually enlarging, painless, symmetrical lesions on the dorsolateral aspect of both ankles.</p><p>He is otherwise well, with no past history of note and no other symptoms on systems review.</p><p>Ali works in a full-time, desk-based role. He is devoutly religious and prays for approximately an hour a day.</p><p>This involves kneeling and sitting back on the dorsolateral aspect of the ankles, usually barefoot on the floor or a rug.</p><p>On examination, the only findings of note are two well-demarcated, non-tender, hyperkeratotic plaques, anterior to the lateral malleoli bilaterally (pictured).</p><p>These are of similar size and thickness and are distributed symmetrically on the ankles.</p><p>Dermatoscopic examination demonstrates hyperkeratosis, with no visible vessels or ulceration.</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.