Author Response

Dear Dr. Cacchio,

We appreciate your interest in our work on proximal hamstring tendinopathy, and commentary regarding our study “Platelet-rich plasma treatment improves outcomes for chronic proximal hamstring injuries in an athletic population”1. We apologize for any confusion that may have occurred in the interpretation of your data from the randomized controlled trial entitled “Shockwave Therapy for the Treatment of Chronic Proximal Hamstring Tendinopathy in Professional Athletes”2. When reviewing your results, all commentary in the text for both the primary outcome measures (Pain, NPRS), as well as the secondary outcome measures, specifically and only addressed the results at 3 months, with no comment on the outcomes at 6 and 12 months for any endpoint. This was the origin of our misinterpretation, and we apologize for that.

Furthermore, we appreciate your review and comments on our technique, methodology, and limitations. We were very aware at the time of publication that the strength of this paper is limited by a small cohort, lack of control, and short term follow up, and we did attempt to address these in the “Limitations” section of the paper. Undoubtedly, there are ample clinical measurements, such as strength or specific clinical tests, which could have been obtained and incorporated. As you stated very nicely in your paper, there is “no validated disease-specific questionnaires available for PHT”. Therefore, we also chose pain severity (VAS) and recovery (our return to activity and patient-perceived recovery questionnaire) as our outcome measures. We appreciate your interest and commentary, and hope this can stimulate further investigation into both PRP and proximal hamstring injuries in the future.