Table 2. Characteristics of included studies.
* ALL: sample size number, including patients who underwent surgical and conservative therapies.
** Conservative: non-surgical therapy (including exercise and drug therapy).
*** SD: standard deviation
**** Affected meniscus: medial, lateral, longitudinal vertical, horizontal, complex degenerative, radial, and vertical flap.
***** Meniscus ghost sign: medial meniscus posterior root radial tears.
****** Meniscus symptoms: clicking, catching, popping, giving way, pain with pivot or torque, pain that is episodic.
BMI: body mass index; RCT: randomized controlled trial; KL: Kellgren-Lawrence classification; ET: exercise therapy; APM: arthroscopic partial meniscectomy; PT: physical therapy; MeTeOR: meniscal tear in osteoarthritis research; HAI: hyaluronic acid injection; OA: osteoarthritis; AAE: adapting alignment exercise; MTE: muscle training and exercise; MMPRT: medial meniscus posterior root tear
| Author, year | Country | Study design | Sample size | Age*** (years) | BMI*** (kg/m2) | Types | Intervention | Comparison | Study purpose/Aims/Objectives | ||
| ALL* | Conservative** | Meniscus injury | Knee osteoarthritis | ||||||||
| Graaf et al., 2018 [13] | Netherlands | Cluster RCT (crossover) | 321 | 161 | 57.3 ± 6.8 | 27.2 ± 4.0 | Affected meniscus**** | KL: grades 0–3 | ET | APM | To assess whether PT is non-inferior to APM for improving patient-reported knee function in patients with meniscal tears |
| Berg et al., 2020 [16] | Norway | RCT | 140 | 58 | 50.3 ± 6.2 | 26.2 ± 4.0 | Medial meniscus tear | KL: grades 0–2 | ET | APM | To assess the course of radiographic features five years after ET or APM |
| Kise et al., 2019 [23] | Norway | Prospective RCT | 107 | 55 | 50.1 ± 6.1 | 25.7 ± 4.0 | Medial meniscal grades 2, 3a, and 3b | KL: grades 0–1 | APM | ET | To identify the prognostic factors for two-year patient-reported outcomes in middle-aged patients with degenerative meniscal tears treated with ET or APM |
| Kise et al., 2016 [24] | Norway | Cluster RCT (crossover) | 140 | 70 | 50.2 ± 6.2 | 26.4 ± 4.3 | Meniscus degeneration | KL: grades 0–3 | APM | ET | To determine whether ET is superior to APM for knee function in middle-aged patients with degenerative meniscal tears |
| Ahn et al., 2015 [25] | Korea | Retrospective study | 41 | 13 | 62.3 ± 7.17 | 26.37 ± 4.01 | MMPRT | KL: grades 1–4 | MMPRT repair | PT | To compare the clinical results of conservative treatment and pull-out repair of MMRT and to analyze the prognostic factors of MMRT repair to determine repair indication |
| Lim et al., 2010 [26] | Korea | Retrospective study | 30 | 30 | 59.0 (51–65) | Not defined | MMPRT | KL: grades 0–2 | PT, medications | Not defined | To investigate the clinical results of non-operative treatment of degenerative (non-traumatic) posterior root tear of the medial meniscus |
| Yim et al., 2013 [27] | Korea | RCT | 102 | 52 | 57.66 ± 11.0 | 26.46 ± 1.9 | MMPRT (Horizontal tears) | KL: grades 0–1 | PT, medications | APM | To compare the clinical results of arthroscopic meniscectomy and non-operative treatment for degenerative horizontal tears in MMPRT |
| Noorduyn et al., 2020 [28] | Netherlands | RCT | 321 | 162 | 57.3 ± 6.8 | 27.2 ± 4.0 | Meniscus tear | KL: grades 0–3 | APM | ET | To compare APM with PT in patients with a degenerative meniscus tear, focusing on patients’ most important functional limitations as the outcomes |
| Ikuta et al., 2020 [29] | Japan | Prospective RCT | 26 | 13 | AAE: 67.9 ± 7.2 MTE: 68.2 ± 10.8 | AAE: 22.9 ± 2.3 MTE: 24.2 ± 2.3 | Meniscus ghost sign***** | KL: grades 1–2 | AAE | MTE | To verify that exercise aimed toward improving knee kinematics reduces the knee adduction angle during walking and prevents rapid cartilage degeneration in the medial compartment of the knee |
| Kudo et al., 2013 [30] | Japan | RCT | 209 | 81 | Group: 63.8 ± 5.9 Home: 65.6 ± 5.8 | Group: 23.8 ± 2.9 Home: 23.8 ± 3.0 | Mink grades 0–3 | KL: grades 0–4 | ET (group) | ET (home) | To evaluate how mode of treatment delivery affects knee OA symptom improvement and to analyze potential factors affecting improvement after ET |
| Stensrud et al., 2015 [31] | Denmark | RCT | 82 | 40 | 49.2 ± 6.4 | 26.9 ± 4.1 | Medial meniscus tear | KL: grades 0–2 | ET | APM | To compare the effects of a 12-week exercise therapy program and APM on knee strength and functional performance in middle-aged patients with degenerative meniscus tears |
| Neogi et al., 2013 [32] | India | Prospective study | 33 | 33 | 55.8 (50–62) | Not defined | MMPRT | KL: grades 0–2 | PT, medications | Not defined | To evaluate the effect of supervised ET on patients with MMPRT |
| Prati et al., 2017 [33] | Italy | Non-RCT (pilot study) | 20 | 8 | 61.3 ± 4.3 | Not reported | Meniscus tear | KL: grades 0–2 | PT (MeTeOR) | APM | To compare the efficacy of PT and APM on physical function in patients with meniscus injuries and symptomatic knee OA |
| Sonesson et al., 2020 [34] | Sweden | RCT | 146 | 61 | 54.0 ± 6.0 | Not reported | Meniscus symptoms****** | KL: grades 0–3 | APM | PT | To evaluate whether arthroscopic knee surgery combined with an exercise program provides an additional five-year benefit over that of an exercise program alone in middle-aged patients with meniscal symptoms; to determine whether baseline mechanical symptoms affected outcomes; and to compare radiographic changes between treatment groups |
| Katz et al., 2013 [35] | United States | Cluster RCT (crossover study) | 330 | 169 | 57.8 ± 6.8 | 30.0 ± 6.1 | Meniscus symptoms****** | KL: grades 0–3 | APM | PT (MeTeOR) | To compare the effectiveness of APM with that of standard PT regimens |
| Başar et al., 2021 [36] | Turkey | Prospective RCT | 146 | 45 | 50.9 ± 4.5 | 28.7 ± 2.2 | Meniscus tear | KL: grades 1–3 | APM, APM and HAI; PT and HAI | PT | To compare the effectiveness of APM and PT in degenerative meniscus tears and investigate the effect of HAI injection |