Two case reports of ring lateral meniscus - A rare anatomical variant

Abstract

Introduction: The ring-shaped meniscus is an infrequent anatomical aberration with very few previous reports. Comparatively, these are reported more commonly in the lateral meniscus than the medial meniscus. Most often they are quiescent and rarely cause any symptom unless for an associated tear or parameniscal cyst. Thorough history taking, proper examination, adequate imaging along with arthroscopic evaluation is essential for diagnosing and treating these anomalies appropriately. Case reports: We report two cases of asymptomatic ring lateral meniscus. The first patient was a 15-year-old girl with ACL insufficiency and the second patient was a 38-year-old doctor with medial meniscus bucket handle tear, three years post anterior cruciate ligament reconstruction. Arthroscopy revealed a stable ring lateral meniscus in both patients. Since these were incidental findings with no correlation to the patient's presenting complaints, it was decided not to touch them. Conclusion: Aberrations of lateral meniscus are many and the ring-shaped meniscus is one amongst the rarest. Knowledge of these malformation is essential to identify and initiate appropriate intervention as needed.

Keywords

• Ring-shaped meniscus
• Lateral meniscus
• Anatomical variant
• MRI