Sally is a 25-year-old recreational runner who presents with a two-week history of left fifth-toe pain.

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<p>Sally is a 25-year-old recreational runner who presents with a two-week history of left fifth-toe pain.</p><p>She reports a sudden onset of pain with associated bruising of the fifth toe during a run one month prior. There was no associated fall or injury.</p><p>Sally completed the run with difficulty, iced the toe for 48 hours, and the bruise resolved. However, she has a residual dull ache at the distal phalanx. This prevents her from wearing narrow shoes and has limited her running.</p><p>Sally is typically well, with a BMI in the normal range and no features of relative energy deficiency in sport or disordered eating. She has had recurrent ankle sprains in the past, usually sustained while running.</p><p>X-rays have previously incidentally shown that she has only two phalanges in both fifth toes.</p><p>On examination, the pertinent findings are swelling and tenderness of the left fifth distal phalanx, palpable nodules on the dorsal surface of the fifth metatarsal, and 4/5 weakness of fifth-toe dorsiflexion.</p><p>There is no tenderness over the metatarsal base. Foot and ankle X-rays are requested, and the key X-ray finding is pictured.</p>

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