A 32-year-old man (white, 75 kg, 182 cm and non-smoker) presented to our emergency department with a 24 hours history of increasing pain on the lateral aspect of his left foot. The patient was unable to bear weight on the affected side, but there was no history of trauma to the ankle. Also no medical history was mentioned.
Clinical examination revealed localised tenderness proximal to the base of the fifth metatarsal, under the surface of the cuboid, in the line of the peroneus longus tendon, associated with warmth and redness. Although there was a full range of motion at the ankle, sub-talar and midfoot joint, but foot passive forced supination and active pronation under resistance produced pain exacerbation.
A plain lateral radiograph showed homogeneous calcification at the lateral aspect of foot, under the surface of the cuboid in the line of the peroneus longus tendon (Figure 1). Laboratory examination showed white blood cells (WBC) = 12100/μl, C-reactive protein (CRP) = 3.1 mg/dl and erythrocytes segmentation rate (ESR) = 10 mm/h.
The patient was treated with a single dose of steroid injection (3 mg Betamethasone Sodium Phosphate + 3 mg Betamethasone Dipropionate mixed with 3 ml xylocaine) delivered at the area of maximum tenderness, following by ankle rest. After injection, the patient obtained dramatic relief from pain and was discharged the next day.
At review two weeks, 6 months and two years later the patient was remained without symptoms. A radiograph obtained after 6 months showed that the area of calcification had disappeared.