A reply letter on “A commentary on "Extracorporeal shockwave therapy improves pain and function in subjects with knee osteoarthritis: A systematic review and meta-analysis of randomized clinical trials" [Int. J. Surg. 2020; 82:64-75]” - Coy, Juan Avendaño-; Comino-Suárez, Natalia; Grande-Muñoz, Jesús; Avendaño-López, Carlos; Gómez-Soriano, Julio (International journal of surgery (London, England), 2021)