Thus far in my “Anatomy of an Injury” series, I’ve discussed how microfracture
Three bones in the body form the knee joint: the femur (thigh bone), tibia (shin bone), and the patella (knee cap). In between the femur and the tibia lies two menisci, cartilaginous rings that are in the shape of a “C.” As just stated, there are two menisci – the medial meniscus and the lateral meniscus. Collectively, their jobs is to improve the congruency and articulation of the knee joint while also serving to assist with shock absorption in the knee joint. Furthermore, the meniscus serves a secondary role in maintaining stability of the knee (though to a lesser degree when compared to the ligaments).
In the athletic population, meniscus tears are often due to an acute mechanism of injury. The classic mechanism of injury for an acute meniscus tear is similar to that of an ACL – a deceleration injury with a component of twisting or cutting on a flexed knee. Therefore, it’s not too surprising that meniscus injuries often accompany an ACL injury, though this is not always the case. When torn, the meniscus can lead to locking and/or catching in the knee, serving as a mechanical block to full knee range of motion.
Meniscus tears are often classified according to their location and size, and this plays a major role in whether or not the doctor decides to repair the meniscus or remove the piece that’s torn – more on this to come later. There are many types and classifications of meniscus tears, but for the purposes of this article, there is one major concept to understand. The outer portions of the meniscus have great blood supply, while the inner portion of the meniscus has poor supply. As a result, the meniscus is much more likely to be repaired if the tear is isolated to the outer portion.
What’s done during the surgery?
It used to be thought that the meniscus serves little to no purpose. As a result, whenever it was torn, the MD would often just remove the meniscus completely. However, it was discovered that this often leads to the development of arthritis in the knee, among other issues. Therefore, the primarily goal nowadays is to always preserve as much of the meniscus as possible in order to maintain optimal health in the knee.
Both meniscus repairs and meniscectomies are performed arthroscopically, making them relatively non-invasive procedures. Let’s start with the meniscectomy, or the removal of the torn piece of meniscus. In general, these procedures are reserved for tears which are located on the inner ? of the meniscus, due to the poor blood supply, and therefore, poor healing ability. A meniscectomy is also more likely to be performed if the tear is larger and more complex. During this procedure, the doctor quite literally goes into the knee joint through the scope and removes the portion of the meniscus that is torn, while leaving the rest of the meniscus alone.
The meniscus is likely to be repaired if the tear is smaller and isolated to the peripheral portions, where there is much greater blood supply, and therefore, greater healing capabilities. Additionally, the doctors are also much more likely to make an attempt to repair the meniscus if there is also a ligament injury at the same time. During this procedure, the doctor will go in through the scope, identify the tear, and stitch it back together, preserving as much of the meniscus as possible.
What does rehab entail?
The rehab process is very, very different for meniscus repairs and meniscectomies. In general, meniscectomies heal much more quickly, and symptoms associated with this procedure are much better. Often times, the biggest limitation early on is post-op pain and small amounts of swelling. Once these two impairments resolve, the goal is to regain range of motion early on and strengthen the knee muscles, which can be progressed relatively quickly. From there, the athlete is exposed to his normal sport-specific drills, such as running, cutting, and jumping. Once these activities can be performed without pain or swelling, he is appropriate to return to practice, and from there, to game action. All in all, this process generally takes anywhere from 2-4 weeks.
Meniscus repairs are a whole different animal, primarily because the rehab specialist needs to protect the repaired tissue while allowing healing to take place. Early on, the goal is to restore full knee extension (straightening) of the knee, but flexion (bending) range of motion is generally limited to 90 degrees for the first 2-4 weeks, depending on surgeon preference. Another early consideration is that patients will have their knee locked in full extension with a brace while weight bearing during this time period. Once the 4 week mark has passed, the training wheels can come off, and the goal is to regain full range of motion of the knee, while progressing knee, hip, and ankle strengthening exercises. This process continues until the athlete has full strength in the legs with full range of motion and no swelling. In general, this entire process takes about 8-12 weeks. From there, the athlete is again exposed to sport-specific exercises and gradually introduced to running, cutting, and jumping. Generally, this process continues for about another month or so, meaning it will take about 4-6 months for the athlete to return to the field.
What are the long-term consequences?
As discussed above, the type of surgery done dictates how long it takes the athlete to return to the field. If a menisectomy is done, the athlete is very likely to return within the same season, especially if the injury happens early in the season. On the other hand, you can expect the athlete to miss the entire season if their meniscus is repaired, but he should be good to go for the following year.
Meniscectomies generally lead to more long-term consequences than meniscus repairs. If a player tears their meniscus and does not have it repaired, he is more likely to develop arthritis in the knee, due to the altered mechanics and ability of the knee to absorb shock. One study that compared NFL players with meniscectomies to those without meniscal injuries found that the average NFL career was 1.5 years shorter, resulting in the players playing, on average, 23 less career games. Moreover, in a review of elite athletes followed over 5 years, another study found that 26% of athletes required a subsequent meniscectomy in the same knee.
Meniscus repairs help to maintain the integrity of the knee and its function, making them the preferred intervention. A systematic review of isolated meniscus repairs in athletes of multiple sports found that 89% of athletes were able to return to the field after this procedure, which is an excellent statistic. This study also found a failure rate of just 9% in professional athletes, meaning the procedure is very effective.
In conclusion, we’ve learned that meniscectomies heal much more quickly but do result in more long-term consequences and may slightly shorten the length of an NFL player’s career. Meniscus repairs are always the preferred method of intervention, but they cause the athlete to miss the entire season. You can, however, expect your fantasy asset to return the following season with little complications – have no fear, Kenneth Dixon owners!
- Logan, M.; Watts, M.; Owen, J.; and Myers, P.: Meniscal repair in the elite athlete: results of 45 repairs with a minimum 5-year follow-up. Am J Sports Med, 37(6): 1131- 4, 2009.
- Eberbach, et al. Sport-specific outcomes after isolated meniscal repair: a systematic review. Knee Surgery, Sports Traumatology, Arthroscopy, 2017.
- Aune, K et al. Return to Play After Partial Lateral Meniscectomy in National Football League Athletes. Am J Sports Med, 42(8), 2014.
- Brophy RH, Gill CS, Lyman S. Effect of anterior cruciate ligament reconstruction and meniscectomy on length of career in National Football League athletes: a case control study. Am J Sports Med. 2009; 37(11): 2102-2107.