Meniscal Tears

In the traumatic young patient’s knee, there is a single episode of injury often with an inability to continue to play or exercise. There is often concurrent swelling to the knee that may appear immediately or over the next 24-48 hours. Immediate joint swelling is typically indicative of a haemarthrosis (bleed into the joint) and is associated with ACL injuries and, less commonly, intraarticular fractures (lipohaemarthrosis). Swelling that develops more over a period of days is more suggestive of an isolated meniscal tear.Source: The acute swollen knee: diagnosis and management – PMC (opens in a new tab)

These injuries may be associated with mechanical symptoms. These include locking, where the patient is unable to fully straighten their knee as a torn piece of meniscus has become caught between the femoral condyle and tibial plateau, or instability, where the patient is unable to trust their knee in concurrent ACL tears.

In the older knee, there is often not that history of trauma. Degenerative meniscal tears are significantly less likely to cause mechanical symptoms, and their prevalence in the asymptomatic population is very high.Source: Prevalence of abnormal findings in 230 knees of asymptomatic adults using 3.0 T MRI – PMC (opens in a new tab)

Clinically, patients typically complain of medial joint line pain. McMurray’s and Apley’s compression tests are often symptomatic and sensitive tests, especially in the younger patient. The knee will be stable unless there is concurrent injury to the ACL and/or MCL on Lachman’s and valgus testing, respectively.Source: Evaluation of the Diagnostic Accuracy of Clinical Examination for Diagnosing Medial Meniscal Injuries Using Arthroscopy – PubMed (opens in a new tab)

The diagnosis will be made from a combination of your clinical history, examination findings (please see above) and, in necessary cases, an MRI scan.

MRI investigations are typically reserved for traumatic cases in the younger patient or in those patients with ‘mechanical symptoms’ where surgical workup is being considered. For older patients without mechanical symptoms, often a plain film X-ray will suffice to ascertain the level of OA, as it is significantly less likely that a meniscal tear in this cohort of patients would be treated surgically in isolation.

Treatment options are divided into conservative and surgical.

Conservative options

• For appropriate patients, oral analgesia in combination with a period of unloading can help settle symptoms down. We know that many degenerative meniscal tears will settle down by themselves without any invasive procedures.Source: Prevalence of abnormal findings in 230 knees of asymptomatic adults using 3.0 T MRI – PMC (opens in a new tab)
• Physiotherapy can be helpful in maintaining knee mobility and strengthening the surrounding musculature to reduce knee symptoms in patients with degenerative meniscal tears.Source: A Randomised Trial of Physical Therapy for Meniscal Tear and Knee Pain – PubMed (opens in a new tab)
• In refractory or persisting cases, an ultrasound-guided local anaesthetic and steroid injection +/- joint aspiration (removing any fluid from the joint) can be helpful at easing any associated inflammation that may be persisting. It is usually again utilised for the degenerative tears but can also be helpful in the young population in carefully selected patients that have not improved with other conservative options.Source: Survivorship and outcomes of intra- and perimeniscal corticosteroids injections with structured physiotherapy for degenerative medial meniscus tears – PubMed (opens in a new tab)

Surgical options

Surgery for symptomatic meniscal tears is usually reserved for those with ‘mechanical symptoms’, the younger traumatic knee patients or those that have failed conservative options, especially in the case of the degenerative meniscal tears.

• In the younger patients with a large symptomatic meniscal tear with mechanical symptoms with no signs of joint osteoarthritis, arthroscopy has a clear role and involves meniscectomy (cutting out) or, where possible, a meniscal repair. Repair is often preferred for these patients, as it better preserves knee biomechanics and lowers long-term osteoarthritis risks.Source: Arthroscopic Meniscectomy vs Meniscal Repair: Comparison of Clinical Outcomes – PubMed (opens in a new tab)
• Special note should be made for a specific type of meniscal tear termed a ‘meniscal root attachment tear’. These are usually treated surgically even in the absence of mechanical symptoms due to the strong association with developing early-onset osteoarthritis if left untreated.Source: Medial Meniscus Root Tears: Anatomy, Repair Options, and Outcomes – PubMed (opens in a new tab)

Finally, for degenerative meniscal tears, arthroscopy may be considered if conservative options have not helped, but evidence shows less favourable and consistent outcomes, especially in the presence of developing knee osteoarthritis.Source: Effect of Physical Therapy vs Arthroscopic Partial Meniscectomy in People With Degenerative Meniscal Tears: Five-Year Follow-up of the ESCAPE Randomised Clinical Trial – PubMed (opens in a new tab)