Dr. Richard Cunningham, MD of Vail Summit Orthopedics in Vail, Colorado, explains how he repairs a broken meniscus.
The meniscus is a cushion of cartilage, which rests between the bones of the knee and acts as a shock absorber. Tears of the meniscus are often repaired arthroscopically.
Patients may tear their medial (inside the knee) or lateral (outside the knee) meniscus. The medium tears of the meniscus are much more common than the lateral tears of the meniscus.
Symptoms of a torn meniscus
Patients often experience well-localized pain, burst, or capture. Squats usually increase pain. There is often minimal swelling present.
Unlike bone or muscle, meniscal tissue has a very poor blood supply. As such, it has a very low healing potential. Most patients will tear along the thin, inner edge of the meniscus where there is no blood supply. These tears can not be repaired. Instead, Dr. Cunningham removes only the broken portion of the meniscus and retains most of the healthy and functional portion of the meniscus as much as possible.
In a typical tear of the meniscus requiring arthroscopy, 10-15% of the meniscus has to be removed. If a patient has minimal arthritis (wear of the cartilage coating on the end of the femur and / or tibia), then the patient can expect a great result. If there is a meniscus tear and arthritis, then the result is usually inversely related to the severity of arthritis (ie, the worse the arthritis is, the less optimal the result). There is no need for crutches or an orthopedic device after an arthroscopic meniscectomy.
Arthroscopic Meniscal Repair
If the meniscus tissue breaks in the peripheral 3 mm (where there is blood supply), the meniscus can be repaired and preserved. Repairing the meniscus is always Dr. Cunningham's preference.
The so-called "bucket mango tears", where the meniscus tears longitudinally along the outer edge and then gets into the center of the knee like a cube handle, are the tears Dr. Cunningham commonly repairs.
The alternative to repairing these tears from the hub handle is to remove 50% or more of the meniscus. The removal of this amount of meniscus, which is the "shock absorber" cartilage, is known to predispose the knee to early arthritis.
The gold standard for meniscus repair is to pass the sutures "from the inside out." While viewed through the arthroscope, the sutures are precisely passed through the meniscus and are attached to the knee joint capsule. There are new "all-in" meniscal repair devices where the sutures do not have to pass through a small incision outside the knee. Dr. Cunningham uses all these internal devices for smaller tears or hard-to-reach tears.
Recovery and Rehabilitation
Rehabilitation after meniscal repair is more complicated than after arthroscopic meniscectomy. For a repair, the patient is kept on a knee brace with the knee locked straight whenever walking for 6-8 weeks, depending on the size of the tear.
However, immediately after surgery, we recommend that you unlock the clamp or remove it when you sit down and start a soft knee of movement exercises. After 6-8 weeks, the device is discontinued, but squatting is not allowed for up to 12 weeks, as this places high cut-off stresses on the repaired meniscus, and we want to be sure that it has been given the opportunity of healing.
Unfortunately, not all meniscus repairs heal despite our best efforts. This is again due to the poor blood supply and the compromised curative potential of the meniscus. We do not perform MRI scans to confirm healing, as these are not reliable. Instead, we looked for the symptoms of a meniscus that did not heal, which are very similar to the symptoms patients had before surgery (capture, blockage, pain well located above the meniscus).
For more information on postsurgical rehabilitation, see Dr. Cunningham for more information.
Video credits to Vail Knee YouTube channel