Removal of Osteoid Osteoma of the Calcaneus Using Subtalar Arthroscopy.

Intra-articular calcaneal osteoid osteoma is a very rare condition and the diagnosis as well as the treatment is extremely challenging. We report a case of a 19-year-old male with intra-articular osteoid osteoma of the calcaneus, initially treated for peroneal tenosynovitis with unsatisfactory results. Thorough diagnostic procedure revealed the superolateral location of a calcaneal osteoid osteoma, near the sinus tarsi. A cherry-red elevated lesion typical of an osteoid osteoma nidus was completely removed arthroscopically using the anterolateral portal and the middle portal for subtalar arthroscopy. Histopathology confirmed the suspected diagnosis. The postoperative clinical course was uneventful with immediate pain relief and full weightbearing and movement allowed soon. The patient had no recurrent pain and normal joint mobility 8 months postoperatively. Considering the accessibility of the lesion, intra-articular osteoid osteoma of the calcaneus can be successfully treated arthroscopically using lateral approach for subtalar arthroscopy. LEVELS OF EVIDENCE: Therapeutic, Level IV: Retrospective, Case report.