A rare case of juxtaarticular osteoid osteoma of the calcaneus initially misdiagnosed as juvenile chronic arthritis.

Juxtaarticular osteoid osteoma is frequently misdiagnosed because the symptoms may mimic arthritis, and radiographs may not be characteristic. A rare case of subtalar pain lasting 5 years in a female teenager is presented here. The initial diagnosis was monarticular juvenile chronic arthritis. Family history was misleading because her mother had rheumatoid arthritis (RA).