Abstract
Dear Editor and colleagues,
We appreciate your comments and concerns and appreciate academically reaching out to us with an elegant letter and genuine interest in our article “Knee Osteoarthritis: Clinical and MRI Outcomes After Multiple Intra-Articular Injections With Expanded Autologous Adipose-Derived Stromal Cells or Platelet-Rich Plasma.” 1
We agree with your concerns about the wide variety of platelet-rich plasma preparations and the lack of standardization. Likewise, recent systematic reviews have additionally found an alarming lack of reporting quality of the orthobiologics studies.2,3 Our team conducted a systematic review on injectable orthobiologics in professional football players, revealing that less than 10% of the studies reported platelet-rich plasma characteristics. 4 In that sense, our commitment to the scientific community was to ensure adequate reporting of our platelet-rich plasma (as a control group) and adipose-derived stromal cells preparation and treatment following the DOSES guidelines 5 and allowing adequate reproducibility of our study and outcomes. In fact, we are promoting adherence to these reporting guidelines as part of manuscript submissions by editors and reviewers to improve the overall quality of the studies. 6 We strongly believe that improving the reporting quality of orthobiologics studies is the first step to pursuing this so-longed standardization.
On the other hand, contrary to the cited study by Xu et al., 7 our senior author (M.A.K) performed all the ultrasound-guided injections. Thus, the potential lack of accuracy in the delivery due to different ultrasound operators did not cause any bias in our experimental data. Finally, we disagree on implementing second-look arthroscopies in the cartilage assessment of osteoarthritic knee patients. Less-invasive methods, such as delayed gadolinium-enhanced magnetic resonance imaging that allows assessment of glycosaminoglycans concentration in the extracellular cartilage matrix, and thus, cartilage quality, with reliability and no additional morbidities would be our preferred method. 8 Future studies assessing cartilage regeneration with injectable orthobiologics using this magnetic resonance imaging modality will be valuable to the current knowledge.