Older athletes consist of a relatively healthier population with a high desire for return to sport despite knee injury. A meniscal tear is a common injury that has lasting impacts on joint function and activity level. Lower extremity loading from sporting activity in conjunction with degenerative meniscal changes increases the risk of meniscal tear in older athletes. Optimal treatment of degenerative meniscal tears is often debated with varying studies reporting the benefits of strictly nonoperative treatment or the value of surgery. Postoperative rehabilitation is crucial to enhance the possibility of return to sport.
Key points
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The older athlete is part of an active and healthier population with a strong desire for return to sport.
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Managing patient expectations is a crucial part of initial and continuing evaluation and treatment in this population. Understanding patients’ expected clinical outcome and desired return to play should direct the treatment modality.
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With higher activity, unstable meniscal flaps and horizontal tears may be more symptomatic.
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Retain as much viable meniscus as possible if surgery is done.
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If history, physical examination, and imaging demonstrate a symptomatic meniscal tear in an older athlete with minimal arthritis changes present, then the treating surgeon need not exclude these patients from possible arthroscopic treatment solely due to age.
Introduction
The meniscus is necessary for joint stability, load transmission during weight bearing, and for maintaining the health of articular cartilage. It should be preserved whenever possible, as several studies have demonstrated that the overall longevity of the knee joint heavily relies on the integrity of the menisci.
A meniscal tear is a very common diagnosis. Baker and colleagues reported the incidence of isolated meniscal injury resulting in meniscectomy as 61 per 100,000 in the general population. Arthroscopic partial meniscectomy has been reported as the most frequent procedure performed by orthopedic surgeons in the United States, with 50% of those performed in patients aged 45 years or older.
Degenerative meniscal tears are the most common type of meniscal lesions, consisting of nearly 30% of all tears with a peak incidence in patients aged 41 to 70 years. Englund and colleagues reported that 32% of asymptomatic patients aged 50 to 59 years and 56% of patients aged 60 to 90 years had a meniscal tear demonstrated on MRI. In addition, it has been reported that with increasing age, there was an increase in prevalence of meniscal damage in both men and women. These tears may be caused by trauma; however, they commonly have an insidious onset and are associated with complex, multiple tear patterns. Although associated ligamentous injury is common in the younger population, isolated medial meniscus injury is more common in older population.
The role of operative management of a degenerative meniscus injury is highly debated. Most of the literature has concluded that operative management is not superior to physical therapy with the treatment of degenerative meniscal tears. However, most of this literature is weakened by moderate-quality studies with small sample sizes. Although nonoperative management with physical therapy can be indicated and beneficial, symptomatic degenerative meniscus patients with mechanical symptoms often fail and can be treated arthroscopically.
Although degenerative meniscal tears have been extensively studied in the general population, to the author’s knowledge, there are no studies on degenerative meniscal tears strictly in older athletes. However, this is a unique population by having higher risk of meniscal injury due to the participation in sports along with the added risk of degenerative changes to the meniscus. In addition, with higher activity, unstable flaps and horizontal tears may be more symptomatic with an increased risk of persistent symptoms ( Fig. 1 ). As such, the authors review current literature and their approach to symptomatic meniscal tear in an older athlete.
Diagnostic workup
There are many acute and chronic causes for knee pain. The physician should be critical with history and physical to further explore the specific cause. In the older athlete, determining meniscal injury versus osteoarthritis of the knee is essential. Wang and colleagues found a 40% concomitant prevalence of degenerative meniscal tear and osteoarthritis determined by arthroscopy.
The typical symptoms of osteoarthritis include the following:
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Diffuse knee pain that is worse with prolonged ambulation
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Diffuse knee swelling that is worse with prolonged ambulation
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Pain at night or rest
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Knee stiffness
The typical symptoms of meniscal tears include the following:
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Localized pain to the lateral or medial side at the joint line
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Mechanical symptoms (locking, catching, clicking, popping)
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Delayed or intermittent swelling
The contralateral knee should be examined first for comparison. Both knees should be inspected for signs of infection or trauma. Joint line tenderness, locking, palpable clicking, positive McMurray test, positive Apley compression test, and Thessaly test suggest meniscal injury. Although acute meniscal and ligamentous tears usually consist of joint effusion, degenerative tears rarely do unless there is a large displaced meniscus fragment in the joint. Range of motion may be decreased in displaced meniscal tears; however, the patient may also have full active and passive range of motion.
The authors have found that the 2 most valuable physical examination findings include positive McMurray test and joint line tenderness. A positive McMurray test has a sensitivity of 32% to 34% and a specificity of 78% to 86%. Joint line tenderness has sensitivity ranges of 63% to 87%; however specificity ranges only from 30% to 50%.
The physician should be aware that there are overlapping symptoms and findings. Although meniscal injuries are commonly associated with mechanical symptoms, osteoarthritis, patellofemoral syndrome, and loose bodies can also present with clicking, grinding, or popping. Osteoarthritis is a progressive and insidious process with no inciting event. However, Drosos and Pozo found that one-third (28.8%) of the patients with meniscal tears could not identify any specific event or incident that resulted in an injury. This is especially true with degenerative tears. It is common for patients with osteoarthritis to have increased pain and limitation with ambulation; however, Lange and colleagues found that meniscal tears also result in decreased walking endurance and balance performance.
Radiographic knee series should be obtained to further evaluate for knee pathology, especially osteoarthritis. This includes weight-bearing anteroposterior (AP), lateral, and skyline view. Rosenberg projection views can also be beneficial to compare and further analyze the contralateral knee ( Fig. 2 ).
MRI is a valuable noninvasive tool and is the current gold standard for soft tissue imaging of the knee ( Fig. 3 ). However, the medical specialist should also be aware that meniscal abnormalities demonstrated on MRI are not always significant. With advances in MRI over the years, it is common to find asymptomatic meniscal tears in the older population. One study demonstrated 26% of those with meniscal tears were asymptomatic. Brunner and colleagues and Kaplan and colleagues separately found a 20% prevalence of asymptomatic meniscal tears in professional and collegiate athletes. Shellock and colleagues performed a small study with asymptomatic marathon runners (8 men, 15 women; average age: 40 years; average number of years training: 10; average training distance per week: 41 miles) who regularly compete in 26-mile, 50-mile, or 100-mile marathon races. They reported a 9% prevalence rate of meniscal tears. Subanalysis found a 6% prevelance rate in those younger than 45 years and 14% in those aged 45 years or older. More recently, Beals and colleagues performed a systematic review on the incidence of asymptomatic meniscus pathology in athletes. This study consisted of 14 articles and included 295 athletes (208 men, 87 women; age range: 14–66 years, mean: 31.2 years). They reported an overall prevalence of intrasubstance meniscal damage (grade 1 and 2 on MRI) to be 27.2% (105/386), whereas 3.9% (15/386) of knees had a tear (grade 3 and 4 on MRI).
MRI should not be used without insight in the patient’s history and physical examination. Ercin and colleagues found better specificity, positive predictive value, negative predictive value, and diagnostic accuracy with an experienced practitioner than MRI in diagnosing medial meniscal tears. They concluded that a thorough physical examination from an experienced physician is sufficient for diagnosis. Therefore, knowing the symptoms and performing a thorough physical examination is key to diagnosis and in determining the optimal treatment for degenerative meniscal tears.
Treatment and decision-making
Nonsurgical management of degenerative meniscal tears is an initial treatment option that is typically indicated for patients with full range of motion and no mechanical symptoms. Nonsurgical therapy generally includes rest, activity modification, icing, elevation, nonsteroidal antiinflammatories, short-term offloading, and physical therapy. Although several studies have demonstrated mild to moderate clinical improvement in pain, swelling, and overall knee function with dedicated physical therapy programs, there has been limited research that describes the best methods or protocol for conservative treatment. In a study by Kise and colleagues, both arthroscopic partial meniscectomy and supervised exercise therapy provided improvement in clinical outcomes; however, the exercise therapy had positive effects over partial meniscectomy in improving thigh muscle strength. Stensrud and colleagues published a case series of patients with knee pain and degenerative meniscal tears demonstrated on MRI. Twenty patients (aged 38–58 years) underwent 12 weeks of formal strength and neuromuscular training that consisted of plyometrics and single-leg exercises on varying surfaces. Sixteen of the twenty symptomatic patients showed clinical improvement in Knee Injury and Osteoarthritis Outcome Score (KOOS), quality of life, and pain subscales. At 1-year follow-up, this clinical improvement was sustained, and surgery had not been performed in any of the 20 patients.
The traditional indications for surgical management of a meniscal tear include a history of mechanical symptoms including locking, catching, popping, joint line pain, and failure of conservative, nonoperative management. Nevertheless, indication for operative management of symptomatic degenerative meniscal tears in the adult population is controversial and has been debated over the years. There have been several studies recently published, which have called operative management of the degenerative meniscus tear into question. Thorlund and colleagues recently published a systematic review and meta-analysis that evaluated the benefit of arthroscopy. Nine studies were included in their criteria, and after further analysis they concluded that arthroscopy was associated with harm and should not be recommended for older patients with or without signs of osteoarthritis. However, the studies’ inclusion criteria are inconsistent with several nonrelevant, poorly designed studies, including only 5 related to degenerative meniscal tears. In addition, other current, relevant, and valid studies were excluded from the analysis and conclusions. In December 2015, Bollen described the biases in this study stating that “the evidence that arthroscopic intervention for ‘knee pain’ is of no benefit would seem to be thin at best.”
Conversely, there have been several studies showing the beneficial outcomes associated with arthroscopic partial meniscectomy in patients with symptomatic meniscal tears. In 1991, Aichroth and colleagues published the classic study showing the promising outcomes in discomfort and function with patients who underwent arthroscopic debridement. More recently, Gauffin studied 150 older patients (aged 45–64 years; mean: 54 ± 5 years) with symptomatic meniscal tears after undergoing physiotherapy. The patients were randomized into 2 groups, a nonsurgical group that continued a formal physiotherapy exercise program and the surgical group that received the same physiotherapy exercise program but also underwent knee arthroscopy within 4 weeks of presentation, in which significant meniscal injuries were resected. This study reported significantly lower pain at 12 months in the patients who underwent meniscectomy. In addition, they found a significantly larger improvement in KOOS (pain) in the surgical group. It was concluded that partial meniscectomy had substantial benefits when added to physiotherapy programs.
El Ghazaly found similar results with their study of 70 patients (age: 18–67 years, mean: 39.87 years) with unstable meniscal tears. All patients underwent physical therapy 3 times a week for 8 weeks. Those who were unsatisfied and symptomatic were offered arthroscopic partial meniscectomy. Overall this study reported improvement in pain and swelling after physical therapy, yet these were not statistically significant and many of the patients continued to experience limited range of motion of the knee. After arthroscopic partial meniscectomy there was significant improvement with pain, swelling, and overall function of the knee, including in those patients with mild osteoarthritis.
Yim and colleagues performed a randomized controlled trial to investigate operative versus nonoperative management of degenerative meniscal tears. They randomized 102 patients, aged 43 to 62 years, with symptomatic degenerative horizontal medial meniscal tears into an operative group (arthroscopic meniscectomy) and a nonoperative group (physical therapy/strengthening exercises). At 2-year follow-up, they found no difference in functional or clinical outcome scores. Furthermore, there was no significant difference in progression of Kellgren-Lawrence grade demonstrated on radiographs. Nonetheless, this study did not specify how many patients were athletic patients looking to return to sports and exercise. On further analysis the patient demographics in this study included a majority being overweight (meniscectomy group: mean body mass index [BMI] = 25; nonoperative group: mean BMI = 26.4).
Katz and Losina performed a multicenter, randomized controlled trail comparing standardized physical therapy with arthroscopic partial meniscectomy with postoperative physical therapy in patients with meniscal tears and mild to moderate osteoarthritis. This study found that both groups experienced improvement in the Western Ontario and McMaster Universities Osteoarthritis Index physical function score with no significance at 6- or 12-month follow-up. However, at 6 months, 30% (51) of the patients originally assigned to the standardized physical therapy group crossed over and elected to undergo arthroscopic partial meniscectomy (in discretion of the patient and the surgeon). Only 6% (9) of the patients initially assigned to the surgical group ultimately did not undergo arthroscopic operative management. This large cross-over group provides insight into the possibility that many were not satisfied with their results from physical therapy and therefore underwent additional treatment. Furthermore, this result emphasizes the importance of clearly defining patient expectations.
As previously mentioned, the studies are abundant with varying conclusions on the optimal treatment of degenerative meniscal tears. Two recent reviews further determined that even with plenty of studies, we still cannot definitely conclude the optimal treatment of degenerative meniscal tears at this time. This lack of conclusion in the literature provides increased demand for the surgeon to make decisions on a patient-specific basis. Managing patient expectations is a crucial part of the initial visit. Understanding the patient’s expected clinical outcome and desired return to play should direct the treatment modality.
Age has often been a deterrent from operative management. It is common for medical specialists to regard patients aged 50 to 70 years with a meniscus tear, normal radiographs, and no osteoarthritis as a nonoperative candidate. However, through their practice the authors have found these patients to potentially achieve great clinical and functional outcomes, if appropriately indicated. If the examination and imaging demonstrate meniscal tear and the patient remains symptomatic, we should not exclude these patients solely due to age. We must remember that the main goal of operative management of meniscal tears is to decrease pain, prevent early arthrosis, and ultimately provide the patient the opportunity to potentially return to preinjury function and level of activity.
Meniscus Repair Versus Meniscectomy
Meniscus repair is appropriate in the peripheral, unstable, vertical meniscal tears in the vascular zone of the meniscus, whereas most degenerative tears and tears located in avascular zones of the meniscus should be managed with partial meniscectomy. However, with further understanding of tear patterns and proper techniques, indications for meniscal repairs have expanded over the last 10 years to include older patients and more complex tear patterns. Generally, it has been found that complex degenerative tears have limited ability and potential to heal and are usually not appropriate for operative meniscal repair.
The authors’ preferred surgical technique
The patient is positioned supine on the operating table. Pneumatic tourniquet and a side post or leg holder are used on the ipsilateral thigh. After induction of general anesthesia, the joint is evaluated for stability and range of motion. Standard anterior portals are established with a 15 blade. A standard lateral arthroscopic portal is first established followed by a superomedial outflow portal. A 30-degree arthroscope is used. The location of the medial portal is determined using needle localization. Portal location is crucial to allow appropriate instrumentation of the involved meniscus without damaging the surrounding articular cartilage. In general, degenerative medial tears require a lower, inferior portal to allow direct access to the posterior medial joint space that can be tight and difficult to instrument. By contrast, when treating lateral meniscus tears the medial portal is placed more superior and proximal to allow instruments in the medial portal to go over the tibial spines while entering the lateral compartment. Typically, the lateral compartment opens more than medial and can be easier to instrument.
Diagnostic arthroscopy should always be the first step that is performed. The meniscal injury is then identified. A handheld meniscus biter and motorized shaver are commonly used to perform meniscal debridement. There are a variety of meniscus trimming instruments including straight, up-biting, side-biting, and others to assist with tears in different locations. It is prudent that the meniscal debris is than irrigated or suctioned out of the knee after debridement is complete ( Fig. 4 ). Once meniscectomy is complete, the surgeon can also treat concurrent synovitis or chondral defects. Synovectomy and chondroplasty by removing unstable cartilage flaps can be performed.
