The Torn Meniscus - Poor Blood Supply, Poor Healing Potential
As a sports medicine surgeon, meniscus tears are something I deal with on a daily basis.
Unlike bone or muscle, meniscus tissue has a very poor blood supply. As such, it has poor healing potential.
Most patients tear along the thin, inner rim of the meniscus where there is no blood supply.
Arthroscopic Meniscal Repair
These tears cannot be repaired. Instead, in order to alleviate the pain, patients often come to arthroscopy where a telescope-like instrument is placed in the knee and the small torn portion of the meniscus is removed while preserving as much of the healthy, functioning portion of the meniscus as possible.
In a typical meniscus tear requiring arthroscopy, 10-15 percent of the meniscus has to be removed. If a patient has minimal arthritis (wearing of the coating cartilage on the end of the femur and/or tibia), then the patient can expect a great outcome.
If there is a meniscus tear and arthritis, then the outcome is typically inversely related to how severe the arthritis (ie. the worse the arthritis, the less pain relief there is). There is no need for crutches or a brace after arthroscopic meniscectomy and most patients are recovered within weeks.
When Can The Meniscus Be Repaired?
If the meniscus tissue is torn in the peripheral 1/3 where there is blood supply, the meniscus can be repaired and preserved.
People ask me what I think about repair, and my answer is this: repairing the meniscus is always my preference.
Bucket Handle Tears
So-called “bucket handle tears” where the meniscus tears longitudinally along the outer rim and then flips into the center of the knee like a bucket handle, are amenable to repair.
The alternative to repairing these bucket handle tears is to remove 50% or more of the meniscus. Removing this amount of the meniscus, which is the “shock absorber” cartilage, is known to predispose the knee to early arthritis, and this should be avoided if possible.
The "Gold Standard" For Meniscus Repair
The gold standard for repairing the meniscus is to pass sutures “inside–out.” While viewing through the arthroscope, sutures are precisely passed through the meniscus and tied over the capsule of the knee joint.
There are newer “all-inside” meniscal repair devices where sutures don’t have to be passed through a small incision made outside the knee. I use these all inside devices for smaller tears or for hard to reach tears.
Rehabilitation After Meniscus Tear
The rehabilitation after a meniscal repair is more entailed than after an arthroscopic meniscectomy.
For a repair, the patient is kept in a knee brace with their knee locked straight whenever up and walking for 6–8 weeks, depending on the size of the tear.
However, immediately after surgery, we encourage you to unlock the brace or remove it when sitting down and start gentle knee range of motion exercises.
After 6–8 weeks, the brace is discontinued, but no squatting is allowed for up to 12 weeks as this places high shear stresses on the repaired meniscus, and we want to be sure it has been given every opportunity to heal.
Do All Meniscus Tears Heal?
Unfortunately, not all meniscus repairs heal despite our best efforts. This is again due to the poor blood supply and compromised healing potential of the meniscus.
A MRI is somewhat helpful to see if the meniscus has not healed but more importantly, we look for symptoms of a meniscus which did not heal which are very similar to the symptoms patients had before surgery (catching, locking, well-localized pain over the meniscus).
Meet Dr. Richard Cunningham
Dr. Cunningham is a full-service knee and shoulder specialist with particular expertise in ACL reconstruction, rotator cuff repair, meniscus preservation surgery, and shoulder instability surgery.
He is a US Ski Team Physician and works with athletes at all levels to get them back to the sports they enjoy.