Floating meniscus

In this condition the menisco-tibial ligament - which usually anchors the meniscus - tears away from the tibia bone on its lower surface. This allows it to 'float up' if there is excess joint fluid or the knee is irrigated with fluid under pressure. This is most obvious on an X-ray.

(IMAGE: left: intact attachment, right: avulsed).

What causes meniscal avulsion?

A meniscal avulsion may be the result of a twisting injury or of degeneration from an earlier problem within the body of the meniscus.

Back to top

The meniscus itself is not torn

The MRI scan shows a fluid gap between the bottom of the meniscus and the tibia bone. Generally, the meniscus itself remains intact, but without this anchorage the meniscus eventually becomes incompetent as a shock absorber and arthritis may ensue if the situation is not surgically remedied.

Back to top

Peer-reviewed papers

• The “Floating” Meniscus: MRI in Knee Trauma and Implications for Surgery

  Citation: Bikkina RS, Tujo CA, Schraner AB, Major NM. The "floating" meniscus: MRI in knee trauma and implications for surgery. AJR Am J Roentgenol. 2005 Jan;184(1):200-4. doi: 10.2214/ajr.184.1.01840200. PMID: 15615974.

  Quote:

  "The presence of a floating meniscus on MRI is a result of significant trauma to the knee leading to meniscal avulsion and is often associated with significant ligamentous injury."

Back to top