Torn meniscus: how to recover

A torn meniscus accounts for around a quarter of all injuries to the knee joint. It can affect young, active people as the result of trauma during sport, or older people because of degenerative changes. But what exactly are the menisci, and how is a meniscal tear diagnosed? Is physiotherapy more effective than surgery?

In this article we will answer these questions, look at when to see a specialist in musculoskeletal conditions and what to do to resolve the problem. In particular, we will look at the most common and effective exercises recommended during rehabilitation after a meniscal tear.

The menisci: what are they?

Many people have heard, especially in sport, of someone who has “torn their meniscus” without knowing what that actually means. So what are the menisci? They are crescent-shaped fibrocartilage structures (you can think of them as cushions) with a triangular cross-section, located on the lateral (outer) and medial (inner) sides of the knee joint, between the femur and the tibia. Their blood supply is quite unusual because it decreases with age: in children, more than half of the meniscus has a blood supply, whereas in adults only 10-30% does, mostly in the outer part (known as the vascular or “red” zone). This is also where free nerve endings and mechanoreceptors are found, while they are completely absent from the inner part (known as the avascular or “white” zone).

Because of this limited blood supply, healing times after a meniscal tear depend on several factors, which we will look at later. The medial (inner) meniscus is C-shaped. The medial collateral ligament attaches to it, and together they stabilise the knee joint, especially against valgus stress. It is less mobile and therefore more prone to injury. The lateral meniscus, by contrast, is O-shaped and has no connection to the lateral collateral ligament. Because it is more mobile, it is rarely injured or torn.

How do the menisci move? When the knee extends, they move forwards, both because of the shape of the joint and because of the pull of the quadriceps. When the knee bends (that is, when we bend the leg), they move backwards. Now that we know what the menisci are, let’s see what they do. Their main functions are:

• Shock absorption: reducing the friction forces acting on the joint.

• Load distribution: increasing the contact area between the femur and the tibia, which reduces stress on the joint and helps prevent early degenerative changes (such as osteoarthritis).

• Joint stability: improving the fit between the bone surfaces.

• Joint nourishment: lubricating the cartilage and supplying nutrients through the synovial fluid.

• Proprioception: contributing to the knee’s sense of position and movement through the mechanoreceptors and free nerve endings.

Torn meniscus: causes

A meniscal injury mainly affects young people, particularly those who play sport (contact or non-contact, such as football, rugby, basketball, skiing or tennis) involving sudden stops, jumps and changes of direction. They are more likely to suffer a tear, especially of the medial meniscus, as a result of a traumatic event. In older people, a degenerative tear (meniscal degeneration) is more likely, especially in those whose activities involve frequent squatting. The main risk factors, that is, factors that make injury more likely, are: being female, older age, a high body mass index (BMI), low levels of physical activity, or delayed repair of the anterior cruciate ligament (ACL).

One of the most common mechanisms of injury affects the “posterior horn of the medial meniscus”, especially when returning to extension from full flexion (as in a deep squat). The medial meniscus becomes trapped at the femoral condyle and, unable to slide forwards, is pinched at the posterior horn.

How can a meniscal tear be identified? A specialist physiotherapist can use a number of tests, in particular the McMurray, Apley, Thessaly and Ege tests, which assess the integrity of the meniscus. A positive result (that is, one that reproduces the patient’s pain) may point to a meniscal problem. It is important to stress that combining the results of several tests remains the best way to improve the diagnostic accuracy of the physical examination for a meniscal tear.

Is an MRI scan or X-ray always necessary? As with other musculoskeletal conditions (for example, a herniated disc in cases of lumbar sciatica), “pain” does not necessarily mean “tear or injury”. Some people have a meniscal tear visible on MRI but no symptoms at all, while others with significant knee symptoms show no sign of a tear on imaging. A clinical examination showing a mechanical block that limits the full range of movement, or signs of instability, is one of the main reasons for further investigation with an MRI scan or a surgical consultation. Knee arthroscopy is considered the gold standard for diagnosing meniscal tears.

How are meniscal tears classified? By location, we have tears of the anterior horn, the posterior horn or the body. By shape, we distinguish between:

• Longitudinal tears

• Radial tears

• Horizontal tears

• Flap tears

• Parrot-beak tears

• Bucket-handle tears

Meniscal tear: symptoms

The symptoms of a meniscal tear are shared with other knee conditions, because many structures in this joint can become painful (ligament injuries, tendinopathies and so on). That is why a thorough history from a specialist physiotherapist and a careful clinical examination are essential. It is important to ask about the injury itself, including any twisting injuries of the knee (in athletes, the triggering movement is generally a twist with the knee bent), delayed swelling with inflammation of the meniscus (around 6 to 24 hours after the injury) and any episodes of locking or giving way. The main symptoms of a medial or lateral meniscal tear are:

• Pain on palpation of the joint line (medial or lateral)

• Pain and limited movement in full flexion or full extension of the knee

• Swelling

• Haematoma or effusion

• Episodes of locking or giving way

• Joint clicking

• Pain during meniscal tests (positive McMurray and Thessaly tests)

• Pain during everyday activities such as walking, going up and down stairs, kneeling or other weight-bearing activities

Torn meniscus: physiotherapy or surgery?

A meniscal tear can be treated with physiotherapy or with surgery. Which should you choose? The type of treatment depends on many variables, such as the individual’s characteristics and the type of tear. As for surgery, there are different types of operation. They may involve a meniscectomy (total or partial removal of the meniscus, mainly in people over 45) or a meniscal repair (mainly in people under 35). Other types of surgery include meniscal replacement or transplant.

Have you found out that you have a torn meniscus and been told you must have an operation? That is not always the case! Some studies have questioned the role of surgery in improving the symptoms of patients with a meniscal tear. In general, no association has been found between structural damage and self-reported pain or function in daily activities. We can say that surgery should only be considered when conservative treatment has failed or in cases of persistent symptoms.

The first-choice approach, therefore, should be rehabilitation aimed at reducing symptoms, restoring range of motion, muscle strength, balance and proprioception, returning to the main functional activities of daily life and recovering sport-specific movements. According to some studies, physiotherapy is an effective treatment option for people with a meniscal tear and, in the long term, achieves better results than surgery in terms of recovery of muscle strength and function. In a particularly acute phase, anti-inflammatory medication may be useful alongside physiotherapy to reduce pain and swelling.

Torn meniscus: rehabilitation exercises

Are exercises for a meniscal tear effective enough to reduce pain? Which are the most important? To answer these questions, let’s look at a 2017 study in which people aged between 18 and 40 with a meniscal tear (visible on MRI) who were eligible for surgery were followed for 12 weeks, three times a week, with a programme based on education and physiotherapy. The physiotherapy programme was based on exercises aimed at restoring mobility and strengthening the muscles, increasing the difficulty as pain reduced by using light weights, resistance bands, balance boards and so on.

Here are some of the exercises:

• Knee bends with the heel resting on the treatment couch

• Straight leg raises

• Isometric quadriceps strengthening exercises

• Hamstring strengthening exercises

• Half squats and lunges

The patients found the programme feasible, relevant and effective, with significant improvements in symptoms and in function during daily activities and sport. All participants stated that they did not want to have knee surgery after completing the physiotherapy programme.

Meniscal tears: recovery times

As mentioned earlier, because the meniscus has a poor blood supply, recovery times for a meniscal tear depend on many factors, such as the extent and location of the tear and the functional demands on the individual. Generally, 6 to 12 weeks are needed.

Conclusion

Have you found out that you have a torn meniscus and are worried? See an experienced physiotherapist, who will propose a rehabilitation programme aimed at reducing pain, restoring movement and muscle strength, and helping you return to sport as soon as possible.

References

Logerstedt DS, Scalzitti DA, Bennell KL, Hinman RS, Silvers-Granelli H, Ebert J, Hambly K, Carey JL, Snyder-Mackler L, Axe MJ, McDonough CM. Knee Pain and Mobility Impairments: Meniscal and Articular Cartilage Lesions Revision 2018. J Orthop Sports Phys Ther. 2018 Feb;48(2):A1-A50. doi: 10.2519/jospt.2018.0301. PMID: 29385940.

Smith BE, Thacker D, Crewesmith A, Hall M. Special tests for assessing meniscal tears within the knee: a systematic review and meta-analysis. Evid Based Med. 2015 Jun;20(3):88-97. doi: 10.1136/ebmed-2014-110160. Epub 2015 Feb 27. PMID: 25724195.

Tornbjerg SM, Nissen N, Englund M, Jørgensen U, Schjerning J, Lohmander LS, Thorlund JB. Structural pathology is not related to patient-reported pain and function in patients undergoing meniscal surgery. Br J Sports Med. 2017 Mar;51(6):525-530. doi: 10.1136/bjsports-2016-096456. Epub 2016 Sep 16. PMID: 27638845.

Skou ST, Thorlund JB. A 12-week supervised exercise therapy program for young adults with a meniscal tear: Program development and feasibility study. J Bodyw Mov Ther. 2018 Jul;22(3):786-791. doi: 10.1016/j.jbmt.2017.07.010. Epub 2017 Jul 27. PMID: 30100313.

Dr Jessica CammareriPhysiotherapist, OMPT. Specialist in the management of musculoskeletal disorders. She earned the OMPT (Orthopaedic Manipulative Physical Therapist) qualification by completing the Master’s in Manual Therapy Applied to Physiotherapy at the University of Rome Tor Vergata. She works in private practice in Palermo at MET-Studio di Fisioterapia and in Marsala (TP) at Studio Cammareri.