The discoid lateral meniscus in children: a narrative review of pathology, diagnosis and treatment.

Background and Objective: The discoid lateral meniscus (DLM) is a congenital abnormality of the meniscal shape, characterized by a typical central hypertrophy and a diameter larger than a regular meniscus, potentially leading to knee pain and symptoms, especially in children. The present study provides an update and a general review of this uncommon meniscal pathology. The incidence of discoid meniscus is about 0.4-17% for the lateral and 0.1-0.3% for the medial, although, being often asymptomatic, the true prevalence is unknown. We aim to enhance awareness on this subject to medical care provider. Methods: A literature search was performed on PubMed, including articles written in English until October 2021. Key Content and Findings: The articles regarding etiology, diagnosis and management of DLM in children or in patients younger than 18 years were reviewed using the narrative approach. Conclusions: Recent literature has shown that DLM is one of the most frequent congenital anomalies of the knee encountered during childhood. While asymptomatic children with incidental finding can be managed nonoperatively, symptomatic painful DLM should be addressed surgically, restoring typical anatomy using saucerization, tear repair, and stable fixation of the meniscus. The risk of osteoarthritis progression seems to be higher in children with operated DLM, imposing prolonged follow-up and cartilage preserving strategies for these patients.