Meniscal Treatments: Overview
The meniscus is a C-shaped piece of fibrocartilage located at the peripheral aspect of the knee joint. Each knee has two mensicii, the medial meniscus and the lateral meniscus (see Fig. 1) whose purpose is to provide spacers between the tibia and the femur. They prevent friction between these two bones and allow for the diffusion of articular cartilage, thereby providing lubrication and nutrition to the joint.
1. Anterior View of Right Knee
Image credit: http://www.arthroscopy.com/sp05005.htm
The majority of the meniscus has no blood supply (Fig. 2). As a result, if the meniscus is damaged (either from trauma or with age) it is unable to undergo the body’s normal healing process. Therefore, a torn piece can begin to move around inside the joint, get caught between the bones, and cause pain, swelling, and decreased mobility (Fig. 3). The three major treatments for a damaged meniscus are repair, removal, and transplantation.
Figure 2: Peripheral Meniscal Blood Supply
Image credit: http://www.arthroscopy.com/sp05026.htm
Surgery is usually performed on the meniscus arthroscopically. The operation is done as an outpatient procedure using miniature instruments inserted through 1/8” incisions. A small fiberoptic telescope, an arthroscope, is inserted into the joint. Sometimes fluid is also inserted to cause joint distension and to allow for better visualization of the structures within. The surgeon will evaluate the meniscal tear by inspecting it with a blunt probe and the decision to repair or remove is made at the time of this arthroscopic examination.
Figure 3: MRI scans of a healthy meniscus (left) and a torn meniscus (right).http://www.orthoassociates.com/meniscus.htm#MT_Rx