One of the most common injuries in sports medicine, and all of orthopaedics, is a meniscus tear. The meniscus is a C-shaped structure that serves as a shock absorber for the knee. There are two menisci in each knee – one on the inside and one on the outside – between the femur (thigh bone) and tibia (shin bone).
The meniscus is commonly torn with twisting injuries to the knee. Younger patients often have a more traumatic injury, as it requires more force to tear the meniscus. Meniscus tears in young athletes. Unfortunately as we get older, it seems that it becomes easier to tear the meniscus. This change is likely due to changes within the structure and substance of the meniscus itself. Older athletes and patients often describe very simple events that cause injury. Common complaints include squatting to pick something up and feeling a sharp pain twisting a certain way. Sometimes a patient will say that that he or she does not even remember an injury at all. MRI’s can be effective for diagnosing knee pain.
Making the diagnosis of a meniscus tear is fairly straightforward. The patient usually complains of a very specifically localized pain. The patient usually has pain on either the medial (inside) or lateral (outside) side of the knee. Many times the pain will be felt more towards the back of the knee. What surprises many patients is that the pain is not constant. Often the patient will feel pain only with certain activities. For instance, he or she may feel it only with twisting motions, such as turning to change directions. Moving straight, such as walking and running, are often not painful. Squatting motions that involve deep bending of the knee can be very painful.
Unfortunately there aren’t many effective nonoperative treatment options. A tear of the meniscus is a structural problem, and there aren’t good ways to get the meniscus to heal on its own. Medicines, physical therapy, injections, and rest might provide some pain relief, but these options do not usually help the meniscus heal.
I rarely push patients to head straight for surgery for a torn meniscus. Most patients, however, usually complain that they cannot perform the activities, exercises, or sports as they would like, and they usually choose to proceed with surgical options.
When discussing surgery for a meniscus tear, it’s important to understand that there are two fundamentally different treatments for a torn meniscus. One approach is what’s called a partial meniscectomy, in which the inner part of the meniscus that is torn is removed with scissors and a shaver. The other is a meniscal repair, in which the meniscus is essentially sewn back together. Both are performed arthroscopically. Unfortunately it’s not always clear prior to surgery whether a meniscus tear can be repaired or if part of it has to be trimmed out. MRI can be helpful for suggesting whether a meniscus is repairable or not, but it is never known for certain until the surgeon can visualize the meniscus tear arthroscopically.
A partial meniscectomy is fairly straightforward, and in fact, it’s one of the most common surgeries in orthopaedics today. The surgeon uses an arthroscope to look all around and then focuses on the meniscus tear. Most meniscus tears are the types that require the inner part of the meniscus to be trimmed out. The surgeon then uses small scissors and a shaver that can be inserted through the small arthroscopic incisions to trim out the inner part of the tear, creating a stable rim of meniscus that will still serve as a shock absorber. As you would expect, trimming part of the meniscus out does remove some of this shock absorber, thus creating the potential for more wear and tear of the knee over time.
Recovery and rehabilitation from a partial meniscectomy is also fairly straightforward. Usually the patient is allowed to fully bear weight on the leg immediately after surgery. The knee will still be sore and swollen, but the patient is usually able to perform full activity within days to weeks. Complete recovery can take several months.
On the other hand, a meniscal repair is slightly more complicated. Like the partial meniscectomy, the surgeon looks all around the knee for signs of other damage and then focuses on the meniscus tear.
There are a variety of ways to repair the meniscus, but the trend is for the surgeon to use a meniscal repair device that can be inserted through the arthroscopic portals without creating separate incisions. Only certain types of meniscal tears can be repaired, but if such a tear is found, it is usually preferable to do so. If the meniscus can be repaired and it goes on to heal, the repair potentially preserves the entire meniscus to serve as a shock absorber long term, hopefully decreasing the chance for further arthritis down the road. The recovery from a meniscal repair is somewhat longer though. Usually the surgeon will keep the patient from putting all of his or her weight on it for days to weeks after the surgery to protect the repair.