Osteochondritis dissecans of the lateral femoral condyle following total resection of the discoid lateral meniscus

Purpose: The purpose of this study was to describe the clinical presentatio n of 6 athletically active children with symptomatic osteochondritis dissec ans (OCD) of the lateral femoral condyle following total resection for a to rn discoid lateral meniscus and to discuss its cause. Type of Study: Case s eries. Methods: Six patients in whom OCD affecting the lateral femoral cond yle developed after total resection of the discoid lateral meniscus partici pated in a detailed clinical, radiologic, and arthroscopic review. The aver age age at the time of meniscectomy was 9 years (range, 6 to 12 years). At a mean of 50 months (range, 36 to 65 months) after surgery they developed r ecurrent pain in the treated knee; all had radiologic abnormalities at the lateral femoral condyle consistent with OCD. Before the recurrence of pain, all patients had been continuously engaged in sports activity. Radiologic and arthroscopic findings of the OCD lesions were assessed. Clinical outcom es of surgical treatment fur OCD were also documented. Results: The radiogr aphic evaluation showed all lesions to be in the central portion of the lat eral femoral condyle on the anteroposterior views and posteriorly next to a line extending distally from the posterior femoral cortex on the lateral v iews. Arthroscopic evaluation revealed softening in 2 knees, a separated fr agment in 2 knees, and a completely loose fragment in 2 knees. All lesions were treated surgically, including 2 drillings of the lesion, 2 fixations o f separated fragment, and 2 excisions of loose bodies with drilling. At an average follow-up period of 51 months (range, 23 to 77 months), all patient s but 1 were asymptomatic. Conclusions: Repeated impaction in sports activi ties on the immature osteochondral structures under altered mechanical forc e transmission after total resection of the discoid meniscus might be a pre disposing factor in the development of OCD in the lateral femoral condyle.