A 9-year-old boy limps for three months with low grade evening fever and a mildly tender swelling over the right heel. Radiographs show a well defined lytic cavity within the calcaneus with thin surrounding sclerosis, negligible periosteal reaction, and no sequestrum. ESR is raised. Which is the most likely diagnosis?

• A Calcaneal apophysitis (Sever disease)
• B Tuberculous osteomyelitis of the calcaneus ✓
• C Ewing sarcoma of the calcaneus
• D Brodie abscess of the calcaneus

Explanation

Tuberculosis of the short tarsal bones such as the calcaneus produces a relatively well defined cavity with osteoporosis, scanty periosteal reaction, and sequestra are characteristically absent because the indolent infection destroys bone slowly. Sever disease is a self limiting overuse apophysitis with no lytic cavity. Brodie abscess, its closest mimic, is pyogenic and typically shows a dense sclerotic rim with possible sequestration, unlike the picture here.

Reference: Campbell's Operative Orthopaedics, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.