Intra articular osteoid osteoma: a diagnostic problem

Intraarticular osteoid osteomas occurred in 3 patients, one each in the elbow and knee joints and the other in the inferior facet of the fourth lumbar vertebra. The osteoid osteoma that occurred in the articular surface of the olecranon was seen as a case of monoarticular arthritis and had been treated preoperatively as gout and rheumatoid arthritis. Arthrotomy led to the correct diagnosis, a clinical cure of the symptoms and the prevention of degenerative arthritis. The osteoid osteoma in the facet joint in the lumbar spine appeared in the form of painful scoliosis without neurological signs. Removal of the nidus corrected the scoliosis and relieved the pain. Spinal fusion was not necessary. Resection of the nidus of an osteoid osteoma from the medial femoral condyle of the knee joint also resulted in a clinical cure; 18 year followup radiograms showed no degenerative changes.