Increasing great toe pain in a patient with soft tissue swelling and nail enlargement

Question

A 16-year-old boy presented with pain and soft tissue swelling of his right great toe. A clinical photograph is shown (Fig. 1). Radiography, CT, and MRI examinations were performed (Fig. 2, 3, and 4). A photomicrograph of the lesion is shown (Fig. 5).

Fig. 1

Clinical photograph

Fig. 2

Radiograph of the great toe

Fig. 3

Representative CT. a Coronal section. b Sagittal section

Fig. 4

Representative coronal MRI. a T1-weighted image. b T2-weighted image. c Short-tau inversion recovery image

Fig. 5

Histological photograph