Osteoid Osteoma of the Intercondylar Notch: An Uncommon Cause of Knee Stiffness

Osteoid osteomas are self-limiting, benign, bone-forming neoplasms.1,2 First described by Jaffe in 1935,3 these lesions are common and account for 10 to 12% of all benign bone tumors. These lesions almost always occur in patients younger than 30 years, are more common in males than females (approximately 2 to 1 ratio), and over 50% of the time are foundwithin the metaphysis or diaphysis of long bones. Such lesions can be extremely painful, and the classic presentation involves a young patient with night pain in the tibia or femur that is relieved with oral salicylates. The presence of an osteoid osteoma in a periarticular or intra-articular location about the knee is rare. Osteoid osteoma of the knee may present with nonspecific complaints including knee pain, stiffness, effusions, and atrophy. Depending on the clinical setting, these symptoms could represent a variety of different diagnoses, includingmeniscal pathology, chondral pathology, synovitis, or Plica syndrome. Radiographic findings are often normal, and advanced imaging is required for diagnosis and treatment. Although intra-articular osteoid osteomas have been described, there remains a paucity of case reports