Partial Meniscectomy
Arthroscopic partial meniscectomy can be used for the treatment of meniscal tears in patients with concomitant mild to moderate OA who have failed physical therapy or other nonsurgical treatments.

Rationale

The three studies discussed below compare outcomes following arthroscopic partial meniscectomy with physical therapy and demonstrate that knee arthroscopy with partial meniscectomy is as effective as physical therapy.  In PICO 5, this work group recommended supervised or unsupervised exercise as opposed to no exercise to improve pain and function in patients with knee osteoarthritis.  Currently, there are no studies that compare outcomes (knee pain and function) following arthroscopic partial meniscectomy versus physical therapy alone in patients who have failed to improve with an initial course of physical therapy.  It is important to clearly define the appropriate indications for arthroscopic partial meniscectomy in patients with knee OA.  This procedure should be considered in patients with mild-to-moderate knee OA and an MRI confirmed meniscal tear who have previously failed appropriate conservative treatment such as physical therapy, corticosteroid injections, and a course of non-steroidal anti-inflammatory medications.

Katz et al (2013) conducted a multicenter, randomized, controlled trial of symptomatic patients over the age 45 or older with a meniscal tear and evidence of mild-to-moderate knee osteoarthritis to determine efficacy of arthroscopic partial meniscectomy compared to standardized physical therapy in this patient population.   Three hundred fifty-one patients were randomly assigned to surgery and postoperative physical therapy or to a standardized physical therapy regimen (with the option to cross over to surgery at the discretion of the patient and surgeon).  The patients were evaluated at 6 and 12 months and the primary outcome was the difference between the groups with respect to the change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical function score.  The mean improvement in WOMAC score at 6 months was similar between the groups.  At 6 months, 51 patients who were randomized to physical therapy alone (30%) had undergone surgery.  The authors concluded that in their intention-to-treat analysis, there were no significant differences in functional improvement 6 months after randomization; however, 30% of patients in the physical therapy alone group underwent surgery. These patients were analyzed in their original group, based on the intention-to-treat analysis.  

Van de Graaf et al. (2018) performed a multicenter randomized clinical trial in the Netherlands to determine whether physical therapy is inferior to arthroscopic partial meniscectomy (APM) for improving patient-reported knee function in patients with meniscal tears.  Three hundred twenty-one patients were randomly assigned to APM or a predefined physical therapy protocol. Patients were excluded if they had locking of the knee, prior knee surgery, instability caused by anterior or posterior cruciate ligament rupture, severe osteoarthritis (Kellgren Lawrence score of 4), and a BMI > 35 kg/m2.  Change in patient-reported knee function on the International Knee Documentation Committee Subscale Knee form (IKDC) over a 24-month period was used as the primary outcome.  In the PT group, 47 patients (29%) had APM during the 24-month follow-up period.  The authors noted a similar level of improvement in knee function between the APM and PT groups.  They concluded that PT was noninferior to APM for improving patient-reported knee function over a 24-month follow-up period in patients with nonobstructive meniscal tears. 

In 2007, Herrlin et al performed a prospective randomized study to compare knee function and physical activity following arthroscopic partial meniscectomy followed by supervised exercise or supervised exercise alone in patients with non-traumatic medial meniscal tear.  Ninety patients were evaluated using the Knee Injury and Osteoarthritis Outcomes Score (KOOS), the Lysholm Knee Scoring Scale, and Tegner Activity Scale and a Visual Analog Scale (VAS) for pain prior to the intervention and after 8 weeks of exercise and 6 months following intervention. The authors found that after the intervention, both groups reported decreased knee pain, improved knee function, and a high satisfaction (p<0.0001).  They, therefore, concluded that arthroscopic partial meniscectomy was not superior to supervised exercise alone in terms of reduced knee pain, improved knee function, and improved quality of life. 

Benefits/Harms of Implementation

Given the risks associated with surgical intervention, only appropriately indicated patients should be considered for partial meniscectomy in the setting of mild to moderate knee osteoarthritis. 

Future Research

We did not identify any studies that compare outcomes (i.e. knee pain and function) following arthroscopic partial meniscectomy versus physical therapy alone in patients who have failed to improve with an initial course of physical therapy, non-steroidal anti-inflammatory medications (NSAIDs), and a possible intra-articular steroid injection.  The three studies reviewed by the work group demonstrate that knee arthroscopy with partial meniscectomy is as effective as physical therapy.  Future studies should seek to compare outcomes in patients with mild to moderate knee osteoarthritis and an MRI confirmed meniscal tear who have undergone partial meniscectomy after failing to improve with a course of conservative treatment (NSAIDs, steroid injection, and physical therapy) versus those who have undergone partial meniscectomy without a dedicated course of conservative treatment.