The Incidence of Osteochondritis Dissecans in Adolescents Complaining of Chronic Anterior Knee Pain

Abstract

PURPOSE: Osteocondritis dissecans (OCD) is a rare condition in which avascular necrosis of subchondral bone may lead to fragmentation of the avascular portion commonly into the joint space. OCD can progress to become crippling for adolescents and may require multiple surgeries. If detected in a timely manner, conservative treatment may be utilized to prevent considerable morbidity. We hypothesized that OCD has a high prevalence in pediatric orthopaedic patients complaining of chronic anterior knee pain without inciting trauma. We also hypothesized that 4 view x-ray screening in these patients is an effective diagnostic technique for OCD. METHODS: This was a retrospective chart review. The inclusion criteria consisted of chronic anterior knee pain (greater than two weeks) without causal trauma. Charts from 2009 through 2010 were reviewed. It is standard practice in this clinic to use 4-view radiographs to assess these patients (anteroposterior, lateral, tunnel, and sunrise views). We reviewed radiographs, clinical notes, and demographic data. RESULTS: A total of 134 pediatric patients between the ages of 5-18 were identified over the two year period. Four-view screening radiographs were performed on all 134 patients. Of the 134 patients, 10 were identified and diagnosed with OCD (7.5%). 7 of the diagnoses were in female subjects (9.5% incidence), while 3 were in males (5%). The lesion was in the medial femoral condyle in 7 patients, the lateral femoral condyle in 2, and the patella in one. CONCLUSIONS: This study demonstrates that the incidence of OCD in pediatric patients with chronic anterior knee pain without causative trauma was considerably higher than that of the general adolescent or adult population. The elevated incidence of OCD in this subset of pediatric patients and the importance of its early diagnosis supports the use of four view radiographs in these patients. Failure to identify OCD in its early stages can allow the lesion to progress, with a potentially more invasive treatment and poorer prognosis.