Table 1 Evidence for arthroscopic partial meniscectomy

Randomised control trials

Sihoven and colleagues, 2013 [18]

Multicentre with symptomatic medial meniscal tear

APM

Sham surgery

Symptoms

No significant between-group differences from baseline to 12 months in any primary outcome (LKS, WOMET and knee pain after exercise)

APM not superior to sham surgery in reducing knee symptoms at 12 months

Yim and colleagues, 2013 [16]

Degenerative horizontal tear of posterior horn of medial meniscus on MRI; mean age 53.8 years (range 43 to 62 years); follow-up 2 years

APM, n = 50

Strengthening exercises, n = 52

Symptoms

Both groups reported an improvement in knee pain, function and a high level of treatment satisfaction using VAS, LKS, Tegner activity scale, patient subjective knee pain and satisfaction. No significant between-group differences

APM not superior to strengthening exercises in terms of improved knee pain, function or treatment satisfaction

Katz and colleagues, 2013 [15]

Symptomatic meniscal tear; age ≥45 years; 6-month and 12-month follow-up

APM and postoperative PT, n = 161; mean age 59.9 ± 7.9

PT alone, n = 169; mean age 57.8 ± 6.8

Symptoms

WOMAC at 6 and 12 months improvement in both groups but no between-group differences; 30% crossover from PT alone within first 6 months

APM + PT not superior to PT for pain reduction

Herrlin and colleagues, 2013 [17]

Symptomatic medial meniscal tear and radiographic OA; 24-month and 60-month follow-up

APM followed by exercise therapy for 2 months, n = 47; median age 54 years

Exercise alone, n = 49; median age 56 years

Symptoms

Clinical improvement in both groups on all subscales of KOOS, LKS and VAS (P <0.0001). One-third of exercise-alone patients that failed to respond had a benefit from then having APM

APM + exercise not superior to exercise alone

Herrlin and colleagues, 2007 [14]

Knee pain and underlying OA with medial meniscal tear; mean age 56 years; 8-week and 6-month follow-up

APM and supervised exercise, n = 47

Supervised exercise alone, n = 43

Symptoms

Both groups reported decreased knee pain, improved function and high satisfaction. No between-group differences

APM + exercise not superior to exercise alone

Beidert, 2000 [10]

Painful intrasubstance medial meniscal tear; mean age 30.4 years (range 16 to 50 years); 26.5-month follow-up

Group D: APM, n = 11

Group A: PT and NSAIDs, n = 12

Symptoms

Normal/near-normal IKDC. Group A. 75%; Group D. 100%, P = 0.006

APM superior to conservative therapy

Cohort studies

Englund and Lohmander, 2004 [11]

Retrospective case–control study; meniscal Resection 15 to 22 years prior; mean age 54 years at follow-up (±11 years)

APM or total menisectomy, n = 317

Control group with no meniscal tear, previous surgery or cruciate pathology, n =68

Structure

Radiographic (RR 5.4, 95% CI 2.5 to 13) and symptomatic (RR 2.6, 95% CI 1.3 to 6.1) knee OA more common in operated knees than in controls. Total meniscectomy rather than APM had higher likelihood of knee OA (OR 3.6, 95% CI 1.4 to 9.4)

Menisectomy associated with higher risk of developing knee OA. APM associated with less radiographic knee OA than total menisectomy

Englund and colleagues, 2003 [12]

Retrospective analyses of patients who had undergone menisectomy in an orthopaedic hospital 16 years earlier; mean age 54 years at follow-up (±12 years)

APM or subtotal menisectomy, n = 155; mean age 54.3 years

Age, gender and BMI matched controls, n = 68; mean age: 56.3 years

Structure

Increased RR of knee OA (RR 4.8, 95% CI 2.2 to 12) and symptom development (RR 2.6, 95% CI 1.6 to 4.7) of knee OA in meniscectomy group. Subtotal menisectomy associated with significantly worse joint space narrowing and KOOS scores than APM

APM or subtotal associated with high risk of radiographic and symptomatic OA at 16-year follow-up. Outcomes worse in degenerative tears and extensive resection