The lateral discoid meniscus of the knee is a common morphologic variant with a low incidence of 0.4-5% in Europe and a high incidence of 9.1-10.5% in Asia. Usually, the lateral discoid meniscus causes symptoms in relatively young patients, but some patients do not present with discomfort until middle age, and their complaints are similar to those of a torn non-discoid meniscus. Whether there is a correlation between the discoid meniscus and the lower extremity force lines in middle-aged patients at this time is unclear. To clarify whether untreated lateral disc meniscus tears in middle-aged patients lead to changes in lower extremity force lines, Seung-Ju from Koryo University Medical Center in Korea
Kim et al. conducted a case-review study. The investigators concluded that this study illustrates that middle-aged patients with a torn lateral disc meniscus have a higher rate of internal knee deformity and medial and lateral intervertebral arthritis. Although asymptomatic disc meniscus may not require treatment, long-term follow-up is still needed to determine whether a disc meniscus located laterally reduces knee force line valgus. The presence of a lateral disc meniscus may still increase the risk of degenerative osteoarthritis of the knee.