Reprint requests to: Dr. Wai Yip-Law Department of Diagnostic Radiology, Shin Kong Wu Ho-Su Memorial Hospital.
No. 95, Wen Chang Road, Taipei 111, Taiwan, R.O.C.
Osteochondritis dissecans (OCD) is defined as a focal lesion of subarticular bone in which articular cartilage is characterized by fragmentation and possible separation in a joint. The etiology is uncertain, although trauma and ischemia have been implicated. It most commonly affects the knee joint, followed by the elbow and the ankle joints. OCD typically occurs during adolescence or early adulthood, with joint pain and swelling that worsens with activity. From January 2001 to December 2008, 11 patients with OCD were diagnosed using conventional radiographs and magnetic resonance imaging (MRI). There were seven lesions affecting the knee joint, two lesions in the elbow and two lesions in the ankle, respectively. According to MRI results, two cases were classified as stage I; two cases were classified as stage II; three cases were classified as stage III; and four cases were classified as stage IV. All lesions were confirmed by arthroscopy and pathology.
Osteochondritis dissecans (OCD) is a disorder of ossification involving both bone and cartilage [1]. OCD is the most common cause of loose fragments in the joint space in adolescents and may lead to considerable debility. It most commonly affects the knee joint, followed by the elbow and ankle joints. Very rarely, it affects articulations of the shoulder, hand, wrist, or hip [2]. In the knee joint, about 85% of lesions are on the medial femoral condyle. In the elbow, lesions affect the capitellum of the humerus, and in the ankle the talar dome is most often affected [6, 8, 9]. The etiology of OCD may be multifactorial, including trauma, ischemia, abnormal ossification centers, genetic predisposition, or a combination of these factors [3, 4, 5, 8]. Here we present data on 11 cases of OCD: their clinical course, their radiographic features, and their stages of disease according to archived magnetic resonance images (MRI).
MATeRIAls AnD MeThOD
Magnetic resonance imaging (MRI) records of eleven patients with osteochondritis dissecans of different joints from January 2001 to December 2008 were collected. The age of these patients ranged from 13 yr to 35 yr (mean age: 24 yr). Ten patients were male, and one was female. All patients had received conventional radiographs (anteroposterior and lateral views) and MRIs (Siemens Magnetom Symphony, 1.5T) without intravenous injection of contrast medium. MRIs were configured on T1-weighted spin-echo (520–700/12–20; repetition time in sec/echo time in sec) and T2-weighted spin echo (2900–3200/96–108). Conventional radiography images and MRIs were compared.
ResulTs
Among the 11 patients, there were seven lesions in the knee, two in the elbow, and two in the ankle. No patient had multiple lesions in our study. Seven lesions were completely detected and free in the joint
Imaging Features of Osteochondritis Dissecans
