What does forme fruste of a lateral discoid meniscus mean? what causes this in a 6 year old?

Unusual term: Not a typical radiologic term but means generally an incomplete or 'attenuated' discoid meniscus. Discoid meniscus are present @ birth and can cause symptoms if unstable or torn. A dm is a meniscal cartilage which covers more of the tibial plateau than normal( instead of the normal c - shape).Several different dm occur and are often seen incedentally @ knee arthroscopy.Best of luck!