As the name suggests discoid meniscus are disc shaped cartilaginous cushions within the knee, instead of the typical C-shaped cushions. These are present from birth.
Discoid meniscus most often are present in both knees, more often on the outside part of the knee (lateral meniscus) and often cause no symptoms at all. They are usually picked up on MRI scans as incidental findings.
They can be partial as seen in the picture above or complete and occasionally have abnormal ligamentous attachment.
They can occasionally become symptomatic due to a meniscal tear as they are more susceptible to tears.
The most common symptoms are pain in the knee joint and clicking/clunking within the knee during movement. Occasionally the knee can get locked where the child is unable to straighten the knee. The most common cause for pain in knee and clicking in a child aged 7-10 yrs is a discoid meniscus.
MRI remains the gold standard investigation of choice.
Asymptomatic discoid meniscus picked up incidentally do not require any treatment.
Symptomatic discoid meniscus need saucerization whereby the excess meniscus tissue is removed to leave a stable normal C-shaped rim behind.
Symptomatic discoid meniscus with a peripheral tear needs a repair in addition to saucerization.
For more information about discoid meniscus and its treatment, click on the link www.askthebonedoc.com/book-online