Arthroscopic versus conservative treatment of osteochondritis dissecans of the knee: value of magnetic resonance imaging in therapy planning and follow-up.

Abstract

Magnetic resonance imaging (MRI) was used to control the short-term outcome of osteochondritis dissecans (OCD) of the femoral condyle depending on conservative or surgical treatment at the beginning of therapy. Case series. Treatment planning for OCD depended on the stage on MRI when analyzing the appearance of the interface between parent bone and fragment on T1- and T2-weighted images. Twenty-seven patients received conservative treatment and 46 patients underwent arthroscopic surgery. After 20 to 24 months, patients were re-evaluated by MRI to assess the condition of bony fragment, parent bone, and interface so as to determine partial or complete remission, no change, or progression of OCD. After conservative treatment, MRI showed partial or complete remission in 30% of patients and no change in 63%. Arthroscopic treatment led to remission in 37% and to no change in 57%. Progressive disintegration of OCD was found on MRI in 7% of conservatively treated patients and in 7% of the surgery patients. In 33.3% of the patients initially treated conservatively, it was decided to treat them arthroscopically because of ongoing, unacceptable clinical symptoms. The rates of remission and progression were not significantly different between the groups. The patients' age was significantly correlated to the rate of consolidation. OCD in juveniles under 16 years of age followed a milder course than in adults.