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SAGE Publications Sage CA: Los Angeles, CA

10.1177/19476035231201055
10.1177_19476035231201055
Basic Research
Letters to the Editor
Letter to Editor Regarding Article “Knee Osteoarthritis: Clinical and MRI Outcomes After Multiple Intra-Articular Injections With Expanded Autologous Adipose-Derived Stromal Cells or Platelet-Rich Plasma”
Zhao Sheng 1
Wen Caining 2
Zhang Yuanmin 2
1 School of Clinical Medicine, Jining Medical University, Jining, China
2 Department of Joint Surgery and Sports Medicine, Affiliated Hospital of Jining Medical University, Jining Medical University, Jining, China
Yuanmin Zhang, Department of Joint Surgery and Sports Medicine, Affiliated Hospital of Jining Medical University, Jining Medical University, Jining 272067, Shandong, China. Email: yuanminzhang.med@gmail.com
5 10 2023
6 2024
15 2 200201
31 8 2023
31 8 2023
© The Author(s) 2023
2023
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https://creativecommons.org/licenses/by-nc/4.0/ This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access page (https://us.sagepub.com/en-us/nam/open-access-at-sage).
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pmcDear Editor,

Recently, we carefully read an article titled “Knee Osteoarthritis: Clinical and MRI Outcomes After Multiple Intra-Articular Injections With Expanded Autologous Adipose-Derived Stromal Cells or Platelet-Rich Plasma” published by Khoury et al. 1 and fully agree with the authors’ conclusions. The authors compared the clinical manifestations and magnetic resonance imaging (MRI) findings of patients with knee osteoarthritis who received multiple adipose-derived stromal cells (ASCs) or platelet-rich plasma (PRP), and retrospectively analyzed the prognosis of the patients. The authors found that patients receiving intra-articular injections of ASCs had better clinical and radiographic findings than those receiving intra-articular PRP during long-term follow-up. We strongly agree with the research done by the authors, but there are still some areas for improvement in this article.

First, different PRPs will have different effects on the experimental results. Bennel et al. 2 found that PRP preparations are characterized by heterogeneity and lack a unified standard. Therefore, the results of this study may need to be more generalizable to other studies on PRP preparations. Second, this study lacked a placebo control group. However, some studies have found that choosing PRP as the control group has a better effect than normal saline, corticosteroids, and hyaluronic acid. 3 Therefore, intra-articular injection of PRP may be a new control strategy for patients with knee osteoarthritis.

In this article, the author wanted to compare the therapeutic effects of injecting different drugs into the joint cavity to treat knee osteoarthritis, but there are still some deficiencies overall. Xu et al. 4 conducted a retrospective analysis on the prognosis of knee osteoarthritis patients with intra-articular injection of different drugs and found that in the actual operation process, it cannot be ensured that the same doctor completes the operation of each case. Therefore, the authors should consider the effect of this factor on the experimental results. Second, to evaluate patients’ cartilage regeneration, in addition to imaging methods such as MRI, arthroscopy should also be used as a further evaluation method. 5 Finally, we would like to thank the authors again for their study on intra-articular injection of ASCs or PRP for the treatment of knee osteoarthritis. This work is of great help in the treatment of osteoarthritis.

Acknowledgments and Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article.

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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References

1 Khoury MA Chamari K Tabben M Alkhelaifi K Papacostas E Marín Fermín T , et al . Knee osteoarthritis: clinical and MRI outcomes after multiple intra-articular injections with expanded autologous adipose-derived stromal cells or platelet-rich plasma. Cartilage. Epub 2023 Jun 22. doi:10.1177/19476035231166127.
2 Bennell KL Paterson KL Metcalf BR Duong V Eyles J Kasza J , et al . Effect of intra-articular platelet-rich plasma vs placebo injection on pain and medial tibial cartilage volume in patients with knee osteoarthritis: the RESTORE randomized clinical trial. JAMA. 2021 Nov 23;326 (20 ):2021-30.
3 Filardo G Previtali D Napoli F Candrian C Zaffagnini S Grassi A . PRP injections for the treatment of knee osteoarthritis: a meta-analysis of randomized controlled trials. Cartilage. 2021 Dec;13 (suppl 1 ):364S-375S.
4 Xu Z He Z Shu L Li X Ma M Ye C . Intra-articular platelet-rich plasma combined with hyaluronic acid injection for knee osteoarthritis is superior to platelet-rich plasma or hyaluronic acid alone in inhibiting inflammation and improving pain and function. Arthroscopy. 2021 Mar;37 (3 ):903-15.
5 Aletto C Giordano L Quaranta M Zara A Notarfrancesco D Maffulli N . Short-term results of intra-articular injections of stromal vascular fraction for early knee osteoarthritis. J Orthop Surg Res. 2022 Jun 11;17 (1 ):310.35690837
