A critical overview of systematic reviews and meta-analyses of extracorporeal shockwave therapy for knee osteoarthritis.

Knee Osteoarthritis (KOA) has become a serious health issue for elderly patients. Several systematic reviews (SRs) and Meta-Analyses (MAs) have reported extracorporeal shockwave therapy (ESWT) has widely been used in the treatment of KOA. This overview aims to summarize and evaluate the available evidence for the efficacy of ESWT for KOA. Eight databases were searched from inception to December 4, 2022. The methodological quality of the included SRs/MAs was assessed by Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR 2) and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool was used to assess the quality of the included studies in terms of outcome indicators. Eight SRs/MAs were finally included in this study. The results of the methodological quality of the included SRs/MAs were generally unsatisfactory. The limitations were a lack of explaining the reasons for selection, a list of excluded literature, reporting bias assessment, and reporting the potential sources of conflict of interest. A total of 49 outcome indicators were assessed by using the GRADE tool. Only 3 items were assessed as moderate quality and the remaining indicators were rated as low and very low. Limitations were the most common downgraded factors. ESWT is regarded as a safe and therapeutically effective non-pharmacological method for the treatment of KOA. However, the reliability of the results is affected by the generally low methodological and evidential quality of the included SRs/MAs. Future researchers should improve the quality of original studies and SRs/MAs to provide a higher level of evidence-based medical evidence.