Abstract
Background Discoid lateral meniscus is the most frequent variant of the meniscus. Few studies
have focused on the histology of discoid menisci. The aim of the present study was
to report the histological findings of discoid lateral meniscus in children and adolescents,
after arthroscopic partial resection, to give a possible explanation of its developmental
etiology.
Methods Five patients aged 9, 10, 13, 15, and 17 years were operated on for a 1-piece excision
of a discoid lateral meniscus, and the specimens were histologically examined.
Results The extracellular matrix showed a different distribution and characteristics depending
on the different side of the meniscus. Irregularly oriented collagen fibers in discoid
lateral meniscus were found. Cells of different shapes were observed depending on
the surficial or deep location in the tissue. There were no blood vessels in the inner
part of discoid lateral meniscus.
Conclusion The findings of the current study seem to confirm that discoid lateral meniscus arises
from variant morphogenesis. Furthermore, the altered distribution and shape of the
cells and disorganization of collagen fibers (irrespectively of the age of the patients)
may predispose discoid lateral meniscus to degeneration, damage, and tear in young
patients also.
Level of Evidence Level of evidence 4 (case series).
Keywords
discoid lateral meniscus - histology - children - knee - development
