September/October 2022

Surgery for Meniscus Tears
By Mark D. Coggins, PharmD, BCGP, FASCP
Today’s Geriatric Medicine
Vol. 15 No. 5 P. 10

Research Indicates It’s Overused and Potentially Harmful

Knee injuries are common, with meniscus tears being a frequent source of knee injury and pain. An estimated 750,000 knee surgeries are performed each year to repair torn meniscus cartilage, with arthroscopic partial meniscectomy (APM) being the most common arthroscopy procedure in older adults.1 Despite the routine nature of the arthroscopic procedure, the value of APM continues to come under intense scrutiny due to its high cost and consistent evidence showing that it’s too often ineffective and a waste of health care expenditures while also being potentially harmful to older adults.

Anatomy
Each knee consists of two menisci: the medial (inner) meniscus and the lateral (outer) meniscus. The meniscus is a moon-shaped rubbery section of cartilage that serves as a cushion and absorbs shock between the shin bone and thigh bone and helps to distribute weight across the knee joint. In effect, the menisci allow 50% to 70% of the weight placed on the knee to be transmitted away from the joint cartilage.2 This protects the cartilage from excessive pressures but that protection is dependent on the menisci and their attachments to the bones being intact. Furthermore, the menisci also nourish the joint cartilage, lubricate the joint, and provide stability to the knee.

From prenatal development until shortly after birth, the whole meniscus has blood supply. However, with increasing age, the blood supply recedes and becomes limited to the outer third of the medial and lateral meniscal rims. By 10 years of age, vascularization is present in around 10% to 30% of the meniscus, and at maturity, the meniscus contains blood vessels and nerves only in the peripheral 10% to 25% of the tissue.3

Meniscus Tears
When cartilage is damaged, it is often described as a tear. Meniscus tears may occur due to traumatic injury, degenerative arthritis, and chronic overuse. Acute meniscus tears result from traumatic events from any activity that causes someone to forcefully twist or rotate the knee, especially while they put their full weight on it. These types of meniscus tears are more likely to occur in younger persons who participate in sports such as football, basketball, and soccer. Other activities such as kneeling, deep squatting, or lifting something heavy can also lead to a torn meniscus. The meniscus tears seen in older adults are primarily due to years of wear and tear and degenerative changes in the knee, as seen with osteoarthritis (OA).

Common risk factors include aging, as menisci become more prone to tearing; work-related kneeling and squatting; climbing stairs (more than 30 flights); injury from sports such as football, tennis, and basketball; being overweight or obese; and having degenerative diseases such as OA. Losing 5% to 10% body weight in those who are overweight has been shown to have benefits in both pain and function.4

Symptoms may include pain, instability in the knee joint, inflammation, stiffness, feelings of the knee giving way, and mechanical symptoms such as locking, popping, and catching.

APM
APM is the most common orthopedic procedure performed in the United States and accounts for two-thirds of orthopedic knee surgeries in older adults.5 The aim of the procedure, also referred to as “knee washout” or “meniscus shaving,” is to relieve symptoms attributed to a meniscal tear by removing torn meniscal fragments and trimming the meniscus back to a stable rim (debridement).

Unnecessary and Wasteful
According to a US study reported in JAMA Surgery, many older adults are getting surgery to remove damaged cartilage in the knee even though there is evidence these operations may not help ease pain or improve mobility in people older than 65.6 Of the 121,624 knee arthroscopies performed on Medicare recipients by 12,504 surgeons in 2016, APM-only procedures accounted for more than 81,000, or 66.7%. These unnecessary surgeries add tremendous cost to Medicare and other payers, with each procedure costing as much as $10,000.1

Evidence Against APM
The majority of randomized controlled trials suggest that APM is not superior to nonsurgical conservative treatments including physical therapy, exercise therapy, and cortisone injections to reduce inflammation. Furthermore, APM may lead to additional risks for patients, including OA, accelerated joint degeneration, and accelerated time to total knee replacement (TKR).

APM vs Physical Therapy
In a multicenter randomized controlled trial, symptomatic patients aged 45 and older with meniscus tears and evidence of OA were randomly assigned to APM with postoperative physical therapy or assigned a standardized physical-therapy regimen alone.7 It was found that there was no significant difference in the magnitude of improvement in functional status and pain after six and 12 months between patients assigned to APM and postoperative physical therapy.

APM vs Exercise Therapy
Quadriceps muscle weakness is a risk factor for knee OA, making strengthening this core group of muscles important for persons with degenerative meniscal tears.8 Exercise therapy has been found to be an effective intervention for persons with degenerative meniscal tears and knee symptoms without any associated risks of surgery. Short- and long-term follow-up studies have shown that exercise therapy improves function and activity level in patients with degenerative meniscal tears, regardless of whether they have surgery.9

A small pilot study was the first study to compare exercise alone to APM alone. The study evaluated medical exercise therapy (MET) vs arthroscopic surgery in patients with degenerative meniscus injury and knee pain.10 Nine patients were randomly assigned to MET (three treatments per week for three months), and eight patients were randomly assigned to arthroscopic meniscectomy with no structured conservative therapy after surgery. After three months, there were no statistical differences between the two groups regarding pain and function. An additional benefit was that anxiety and depression were significantly reduced in the MET group compared with the patients receiving arthroscopic surgery.

Another study analyzed patients aged 43 to 62 years with degenerative horizontal tears of the posterior horn of the medial meniscus with OA for two years.11 There were no significant differences between arthroscopic meniscectomy and muscle strengthening exercises in terms of knee pain relief, improved knee function, or increased satisfaction in patients after a two-year follow up.

This randomized controlled trial found that exercise-based physical therapy was not inferior to APM over a period of five years for self-reported knee function. Researchers observed a small and comparable progression of knee OA in both groups. Findings from this trial further support the recommendation that exercise-based physical therapy should be the preferred treatment over surgery for degenerative meniscal tears.

APM vs Steroids
APM has also been compared with the use of intra-articular steroids in treating degenerative medial meniscus tears.12 Although the arthroscopic group performed better in terms of the Oxford Knee Score at one month, the difference was small and was not statistically or clinically significant at one year. The authors concluded that degenerative medial meniscus tears in the presence of OA could only marginally benefit from arthroscopic debridement over intra-articular steroid injections in the short term.

APM Effectiveness on Mechanical Symptoms
Patients with meniscus tears can experience knee locking that can cause significant pain. The rationale for APM often is based on a desire to reduce these mechanical symptoms; however, expectations by patients that removal of the whole or part of the meniscus will restore function and lessen pain are not well founded, and removal of the meniscus can cause additional problems. In a randomized, patient- and outcome assessor-blinded, sham surgery-controlled, multicenter trial, adults (aged 35 to 65 years) with a degenerative medial meniscus tear and no knee OA were randomly assigned for APM or sham surgery.13 APM provided no added benefit over sham surgery to relieve knee catching or occasional locking.

APM Accelerates Degeneration
Removal of the meniscus results in the loss of the important role it plays in providing lubrication to the knee by diffusing synovial fluid, which provides nutrition and acts as a protective measure for articular cartilage across the joint. As a result, there’s accelerated breakdown of articular cartilage between the femur and tibia and the patella and femur bones. As a result, accelerated OA is common in persons who have received APM, as was seen in a five-year post APM surgery follow-up study.13

Increased Need for TKR
Another concern is that arthroscopic meniscectomy may increase the need or accelerate the need for TKR. One study found patients who had received meniscectomy to have a three-fold increase in the risk for future knee replacement surgery.14

In another study, researchers performed a retrospective study of 289 patients aged 50 to 70 years at surgery with diagnosis of degenerative meniscal tear who underwent arthroscopic meniscectomy.15 They collected baseline data, including age, sex, injured meniscus (medial, lateral, or both), knee alignment, OA, associated lesion identified during arthroscopy, and associated procedure performed during arthroscopy. At 20 years of follow-up, the researchers evaluated rate and timing of conversion to TKR and evaluated clinical outcomes using the Knee Injury and Osteoarthritis Outcome Score. There was a 15.7% conversion rate at 20 years from arthroscopic meniscectomy to TKR and a mean time between surgeries of seven years. Subsequent TKR in the 20 years after arthroscopic meniscectomy for degenerative meniscus tears were significantly associated with preoperative OA and chondral lesion, lateral meniscectomy, age at time of surgery, female sex, and malalignment. Furthermore, age greater than 60 years, lateral meniscectomy, and concurrent anterior cruciate ligament reconstruction were negative predictors for poor clinical outcomes at 20 years. Therefore, if patients present with negative predictor factors, the APM should not be proposed as second-line treatment, and nonoperative management should be continued until TKR is unavoidable.

Wasted Health Care Expenditures
The propensity for unnecessary APM procedures may be part of a broader concern that there’s considerable waste in America’s health care system. Despite clear evidence that APM may not work any better than nonsurgical conservative treatments, including exercise therapy, the procedure remains common, especially for older adults. Unfortunately, this questionable practice is in line with the findings of a physician survey conducted by a John Hopkins research team to evaluate ways to reduce unneeded care.16 In that survey, which included 2,106 responses, physicians indicated they believed that at least 15% to 30% of medical care is not needed. The survey found that the physicians surveyed believe 22% of prescription medications, 24.9% of medical tests, 11.1% of procedures, and 20.6% of overall medical care delivered is unnecessary. The median response for physicians who perform unnecessary procedures for profit motive was 16.7%. Physicians with at least 10 years of experience after residency, and specialists, were more likely to believe that physicians perform unnecessary procedures when they profit from them. The top three reasons cited for overuse of resources were fear of malpractice (84.7%), patient pressure/request (59%), and difficulty accessing prior medical records (38.2%).

Final Thoughts
While younger patients with severely damaged cartilage may benefit from APM, there’s significant overtreatment of knee pain in older adults with APM when alternative, less invasive, and less expensive treatment options have been found to be equally effective. Despite APM being considered minimally invasive, there are associated risks from the surgery, including infection, potential for deep vein thrombosis, and pulmonary embolisms. While these risks may be rare, they are less acceptable considering that patients may be receiving an operation that isn’t likely to be helpful and in light of equally effective available conservative treatments. Patients should be informed that they may benefit from weight loss if needed and first-line treatment options, including exercise therapy and physical therapy. APM should be reserved as a last resort after exercise and physical therapy programs have been adequately tried and failed.

— Mark D. Coggins, PharmD, BCGP, FASCP, is vice president of pharmacy services and medication management for skilled nursing centers operated by Diversicare in nine states and is a past director on the board of the American Society of Consultant Pharmacists. He was nationally recognized by the Commission for Certification in Geriatric Pharmacy with the 2010 Excellence in Geriatric Pharmacy Practice Award.

References
1. Common knee operation in elderly constitutes low value care, new study concludes. Johns Hopkins Medicine website. https://www.hopkinsmedicine.org/news/newsroom/news-releases/common-knee-operation-in-elderly-constitutes-low-value-care-new-study-concludes. Published February 28, 2018.

2. Rao AJ, Erickson BJ, Cvetanovich GL, Yanke AB, Bach BR Jr, Cole BJ. The Meniscus-deficient knee: biomechanics, evaluation, and treatment options. Orthop J Sports Med. 2015;3(10):2325967115611386.

3. Makris EA, Hadidi P, Athanasiou KA. The knee meniscus: structure-function, pathophysiology, current repair techniques, and prospects for regeneration. Biomaterials. 2011;32(30):7411-7431.

4. Norris R. Degenerative meniscal tears. The Knee Resource website. https://thekneeresource.com/conditions/degenerative-meniscus-tears/

5. Cullen KA, Hall MJ, Golosinskiy A. Ambulatory surgery in the United States, 2006. Natl Health Stat Rep. 2009;11:1-25.

6. Stahel PF, Wang P, Hutfless S, et al. Surgeon practice patterns of arthroscopic partial meniscectomy for degenerative disease in the United States: a measure of low-value care. JAMA Surg. 2018;153(5):494-496.

7. Katz JN, Brophy RH, Chaisson CE, et al. Surgery versus physical therapy for a meniscal tear and osteoarthritis. N Engl J Med. 2013;368(18):1675-1684.

8. Segal NA, Glass NA. Is quadriceps muscle weakness a risk factor for incident or progressive knee osteoarthritis? Phys Sportsmed. 2011;39(4):44-50.

9. Herrlin S, Hållander M, Wange P, Weidenhielm L, Werner S. Arthroscopic or conservative treatment of degenerative medial meniscal tears: a prospective randomised trial. Knee Surg Sports Traumatol Arthrosc. 2007;15:393-401.

10. Kise NJ, Risberg MA, Stensrud S, Ranstam J, Engebretsen L, Roos EM. Exercise therapy versus arthroscopic partial meniscectomy for degenerative meniscal tear in middle aged patients: randomised controlled trial with two year follow-up. BMJ. 2016;354:i3740.

11. Østerås H, Østerås B, Torstensen TA. Medical exercise therapy, and not arthroscopic surgery, resulted in decreased depression and anxiety in patients with degenerative meniscus injury. J Bodyw Mov Ther. 2012;16(4):456-463.

12. Vermesan D, Prejbeanu R, Laitin S, et al. Arthroscopic debridement compared to intra-articular steroids in treating degenerative medial meniscal tears. Eur Rev Med Pharmacol Sci. 2013;17(23):3192-3196.

13. Sihvonen R, Paavola M, Malmivaara A, et al. Arthroscopic partial meniscectomy for a degenerative meniscus tear: a 5 year follow-up of the placebo-surgery controlled FIDELITY (Finnish Degenerative Meniscus Lesion Study) trial. British Journal of Sports Medicine. 2020;54:1332-1339.

14. Rongen JJ, Rovers MM, van Tienen TG, Buma P, Hannink G. Increased risk for knee replacement surgery after arthroscopic surgery for degenerative meniscal tears: a multi-center longitudinal observational study using data from the osteoarthritis initiative. Osteoarthritis
Cartilage. 2017;25(1):23-29.

15. Aprato A, Sordo L, Costantino A, et al. Outcomes at 20 years after meniscectomy in patients aged 50 to 70 years. Arthroscopy. 2021;37(5):1547-1553.

16. Lyu H, Xu T, Brotman D, et al. Overtreatment in the United States. PLoS One. 2017;12(9):e0181970.