A 62-year-old otherwise healthy nurse visited the outpatient clinic because of a five-month history of a sudden onset of pain in her left foot without preliminary trauma. She describes a painful, sleeping sensation in this foot when walking. Therefore she is unable to fulfil her job. Prior treatment with diclofenac and physical therapy have had no effect. During four weeks of immobilisation in plaster she had no symptoms, but since she is up and using the leg again she is suffering from an unrelenting VAS pain score of 5. On physical examination, the left ankle is slightly swollen, reddish in colour and warm. There is tarsometatarsal tenderness without palpable abnormalities, and no sensory or motor deficits. Laboratory tests including uric acid show no abnormalities. Additional MRI shows bone marrow oedema in the intermediate cuneiform bone, with no other abnormalities (figure 1). The bone scan shows in three-phase positive deviation in the left foot root, at the area of the cuneiform bone (figure 2). The pictures are shown with the patient’s permission.
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