The meniscus plays a vital role in knee biomechanics as it provides shock absorption when we run and jump, aids in joint stability, and buffers against rotational forces. An injury to the meniscus can alter knee joint mechanics, leading to further stress to the meniscus which may result in osteoarthritis of the joint surfaces.
Injuries to the meniscus vary in severity and may present as simple or complex tears in the cartilage, or a complete rupture. Medial meniscus tears are more common than lateral tears.
Meniscal injuries are often seen in athletes as a result of sports injuries. The mechanism of injury is most often sudden movement into knee joint rotation while the foot is still in contact with the ground.
An acute meniscus injury is often described as sharp pain during movement which results in further pain, swelling, and an inability to continue with activity. In degenerative tears, which are more prevalent in older populations, there may not be a specific incident. Depending on the severity and chronicity of the tear, common symptoms include; swelling, localised sharp pain, persistent ache, knee pain with walking, twisting and turning as well as reduced knee bending and straightening due to feeling the knee is “locked”, as well as clicking and catching sensations.
The recovery time for this meniscus injury varies greatly on the type and severity of the cartilage damage. Surgical options are available to treat this injury; however, research shows that in many cases physiotherapy treatment, including specific strength and control exercises, is as effective as knee surgery.
During your rehabilitation, your physiotherapist will be able to advise you on what you can expect with your knee pain and how to safely keep up your activity levels during your recovery.
Essential Anatomy
To better understand meniscal injuries, it is important to understand some basic human anatomy.
The knee joint is made up of the thigh bone (femur) and the shin bone (tibia). The two menisci are C-shaped structures made up of tough, rubbery fibrocartilage. They are positioned on the tibial plateau (top surface of the shin bone) and are concave in shape to allow the ends of the femur to sit within them, which assists with the gliding and sliding of the knee joint during bending and straightening of the knee.
The menisci are connected to the tibia by coronary ligaments. The medial (inside) meniscus is less mobile during knee movement, due to its attachment to the joint capsule and medial collateral ligament. The lateral (outside) meniscus is attached to the joint capsule but not to the lateral collateral ligament, allowing it to translate more posteriorly (backward) during knee bending.
What Causes Meniscal Injuries?
There are two main causes of meniscal injuries:
Acute Injuries: Acute meniscal tears can occur when there is a sudden movement involving rotation, with the foot in contact with the ground. This force can cause a tear and sometimes involves a knee ligament injury as well.
Degenerative injuries: As we age, meniscal cartilage may gradually thin down. This is affected by a multitude of factors including genetics and activity levels. In degenerative injuries, typically there is no specific incident; however, due to the thinning of the cartilage over time, a tear may gradually appear and become symptomatic.
Physiotherapy Treatment of Meniscal Injuries
The first step with any meniscus injury is to make an accurate diagnosis. Depending on your individual circumstances this may be made clinically or may require a referral for medical imaging to see the interior structures of your knee. Once the problem has been surveyed a treatment plan can be devised to address any contributing factors to the injury and to ensure optimal rehabilitation. Contributing factors to on-going functional problems and pain in meniscal injuries are discussed under the headings below.
Mobility:
Common mobility issues include:
- Tight muscles of the quadriceps, hamstrings, or calf muscles
- Difficulty flexing and extending the knee
- Difficulty walking or navigating stairs or uneven ground
- Stiff joints including hips, knees, and ankles
A variety of techniques may be used to address these issues and to mobilise stiff muscles and joints, often leading to improved functional ability.
Control:
Control refers to the ability of an individual to monitor and adjust their body position and posture through a variety of different settings. When it comes to meniscal injuries, control of the knee, hip, and ankle joints during motion is very important. Your physiotherapist will assess your control in a variety of postures to determine if this a contributing factor.
In many cases, control exercises have a beneficial therapeutic effect as they introduce the body to safe and pain-free ranges of motion that the person may not have been aware of.
Strength:
Strength is very important when it comes to the rehabilitation of meniscus injuries. Strong and resilient tissues promote optimal function and are less likely to become tight or weak. They also provide a robust support system for the joints which means they are less likely to become painful when subjected to increased loads or activities involving torsional (twisting) forces. Key muscles that support the knee post meniscal injury include the quadriceps, hamstrings, and gluteal muscles.
Summary
In summary, if you are suffering from a meniscal injury remember these things:
- Meniscal injuries are very common and respond well to physiotherapy treatment
- An accurate diagnosis will help identify and address mobility, control and strength deficits that can affect recovery times
- Strictly following your rehabilitation program will minimise the risk of re-injury and get you back to pre-injury activity levels sooner
If you are experiencing knee pain, book in with your physiotherapist for a thorough assessment using this link – FREE INITIAL ASSESSMENT. An accurate diagnosis will enable a thorough treatment plan to get you back to normal as quickly as possible.
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References
Makris, E. A., Hadidi, P., & Athanasiou, K. A. (2011). The knee meniscus: structure–function, pathophysiology, current repair techniques, and prospects for regeneration. Biomaterials, 32(30), 7411-7431.
McCarty, E. C., Marx, R. G., & DeHaven, K. E. (2002). Meniscus repair: considerations in treatment and update of clinical results. Clinical Orthopaedics and Related Research, 402, 122-134.
Sherman, S. L., DiPaolo, Z. J., Ray, T. E., Sachs, B. M., & Oladeji, L. O. (2020). Meniscus injuries: a review of rehabilitation and return to play. Clinics in sports medicine, 39(1), 165-183.
Spang III, R. C., Nasr, M. C., Mohamadi, A., DeAngelis, J. P., Nazarian, A., & Ramappa, A. J. (2018). Rehabilitation following meniscal repair: a systematic review. BMJ open sport & exercise medicine, 4(1).
Van De Graaf, V. A., Noorduyn, J. C., Willigenburg, N. W., Butter, I. K., De Gast, A., Mol, B. W., ... & Poolman, R. W. (2018). Effect of early surgery vs physical therapy on knee function among patients with nonobstructive meniscal tears: the escape randomized clinical trial. Jama, 320(13), 1328-1337.