[Discoid menisci in children: ultrasonographic features].

OBJECTIVE

Discoid meniscus is a rare congenital pathology affecting mainly the lateral meniscus. Radiological diagnosis, initially based on arthrographic findings, is now established on well defined MRI criteria. In this study, ultrasonography (US) was the modality proposed for diagnosing discoid meniscus and compared to the normal sonographic meniscal pattern. Subjects and methods. 8 children aged from 6 to 11 years, with a symptomatology highly suggestive of meniscal pathology, were investigated by US of both knees, followed by MRI in 3 and arthroscopy in all cases.

RESULTS

In all 8 cases, a meniscus was diagnosed as discoid when it no longer had its normal triangular shape, was abnormally elongated and thick and demonstrated a heterogeneous central pattern. Associated lesions (fracture, cystic degeneration) were well demonstrated on US. The lateral meniscus was involved in all 8 cases, the pathology was bilateral in 5 cases and MRI/US correlation was good in 3 cases. Arthroscopy confirmed US findings in all cases.

CONCLUSION

US, a more widely available imaging modality, is a reliable technique for the diagnosis of discoid meniscus in children.