What is a Meniscus Tear?
The menisci refer to 2 wedge-shaped pieces of fibrocartilage that act as shock absorbers between your femur (thigh) and tibia (shinbone).
The job of the menisci is to help transmit weight from one bone to the other and plays a pivotal role in overall knee stability. It also provides vital nutrition for the articular cartilage that lines the bones within the knee which provides a smooth and lubricated surface for load transmission with low levels of friction. The menisci are located on both the medial (inside) and lateral (outside) of the knee. The medial meniscus is shaped like a ‘C’ and protects the inner portion of the knee. It is also torn more frequently than its counterpart.
Causes of meniscal tears:
Tears of the meniscus are typically caused by shear force between the femur and the tibia bones. In younger patients and particularly athletes, this is typically a twisting force on a flexed (or weight loaded) knee.
Chronic tears can also occur in elderly people and are caused by degenerative changes that can make the knee vulnerable to meniscal tears after minimal stress or trauma.
Common signs and symptoms:
Individuals with a torn meniscus may experience clicking, popping or locking of the knee. This may also be accompanied by pain and tenderness along the knee joint line. Pain during a squat may also be noticed. If the tear is small in size, the meniscus will stay connected to the front and back of the knee. However, if it is large the meniscus may be left only slightly intact. Severe, intermittent sharp pain may then occur, and is localised to that side of the joint.
This results from part of the tear catching between the articular surfaces of the tibia and femur, blocking full extension of the knee and thus causing a ‘locking’ sensation. Inflammation may also cause swelling to occur soon after the injury transpires or several hours later (Sports Medicine Australia).
How is it treated?
Meniscal lesion can either be treated conservatively via physiotherapy intervention or can be treated with surgery. The decision about surgery will depend on where the tear is located, the pattern of the tear, how big it is and what your activity demands are. In degenerative meniscal tears, physiotherapy was shown to be as effective as arthroscopic debridement surgery (Khan et al, 2014).
The goal of physiotherapy is to gain good knee control, range of motion, flexibility and strength to improve knee function (Sylvia et al, 2007). Strengthening exercises are targeted around improving the strength of the quadriceps muscles (particularly VMO) and hamstring muscles which each play a pivotal role in supporting the knee joint. Other treatment strategies incorporated into rehabilitation programs for meniscus tears include improving patellofemoral (kneecap) alignment as well as balance, agility and flexibility training.
For acute and more serious meniscal tears, surgery may be recommended and has a high success rate. The procedure can involve sewing the tear back together, removing the torn section (not usually done as increases risk of premature osteoarthritis) or arthroscopic debridement. Arthroscopic debridement may be required to remove torn fragments as sometimes the meniscus cannot be repaired due to lack of blood supply. It comprises one of the most common procedures in orthopaedics and is typically very successful in decreasing symptoms and allowing people to return to normal activity (Mordecai et al, 2014).
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- Sports Medicine Australia, https://sma.org.au/resources-advice/injury-fact-sheets/meniscus-injury/
- Khan, M., Evaniew, N., Bedi, A., Ayeni, O. R., & Bhandari, M. (2014). Arthroscopic surgery for degenerative tears of the meniscus: a systematic review and meta-analysis. CMAJ : Canadian Medical Association Journal, 186(14), 1057–1064. http://doi.org/10.1503/cmaj.140433
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- Mordecai, S. C., Al-Hadithy, N., Ware, H. E., & Gupte, C. M. (2014). Treatment of meniscal tears: An evidence based approach. World journal of orthopedics, 5(3), 233–241. https://doi.org/10.5312/wjo.v5.i3.233