Are leukocyte-poor or multiple injections of platelet-rich plasma more effective than hyaluronic acid for knee osteoarthritis? A systematic review and meta-analysis of randomized controlled trials

Efficacy and safety of platelet-rich plasma and hyaluronic acid combination therapy for knee osteoarthritis: a systematic review and meta-analysis

BACKGROUND

This study aimed to evaluate whether a combination of platelet-rich plasma (PRP) and hyaluronic acid (HA) is more effective and safer than injection alone for treating KOA.

MATERIALS AND METHODS

MEDLINE (PubMed), the Cochrane Library, EMBASE, and Web of Science databases were systematically searched for articles published until January 2024, and gray literature and bibliographic references were searched. All published randomized controlled trials (RCTs) compared pain, functional outcomes, and adverse events (AEs) associated with PRP + HA therapy vs. PRP or HA treatments. Two independent researchers extracted the pertinent data and evaluated the methodological quality following the PRISMA guidelines. The primary outcomes were pain, functional outcomes, and AEs. A fixed-effects model was used for data analysis in cases with low heterogeneity (P > 0.10 and I2 < 50%). Otherwise, a random effects model was used.

RESULTS

Ten RCTs involving 943 patients were included in the analysis. The statistical findings did not differ between the treatment of PRP + HA and PRP alone, while a discernible enhancement in treatment efficacy was observed when compared to HA monotherapy: the visual analog scale scores at 1- (mean difference[MD], -1.00; 95% CI: -1.37 - -0.62; P < .001), 6- (MD, -1.87; 95% CI: -3.46 - -0.28; P = .02), 12-months (MD, -2.07; 95% CI: -3.77 - -0.38; P = .02), and the Western Ontario and McMaster Universities Arthritis Index total scores at 12-months (MD, -8.82; 95% CI: -14.48 - -3.16; P = .002). The incidence of adverse events was notably lower with PRP + HA than with HA alone (OR, 0.37; 95% CI: 0.19 - 0.69; P = .00) or PRP alone (OR, 0.51; 95% CI, 0.30 - 0.87; P = .01).

CONCLUSIONS

PRP + HA therapy resulted in more pronounced pain and functional improvement in symptomatic KOA patients than HA treatments, and combination therapy may have higher clinical safety than PRP or HA monotherapy.

A Comprehensive Summary of the Meta-Analyses and Systematic Reviews on Platelet-Rich Plasma Therapies for Knee Osteoarthritis

INTRODUCTION

Osteoarthritis (OA), including that of the knee joint, represents a significant proportion of musculoskeletal injuries in the Canadian Armed Forces (CAF) due to the frequent, high-stress physical activity for which member participation is necessary. Platelet-rich plasma (PRP) is a conservative, autologous treatment that has the potential to relieve symptoms and improve functionality of military members to decrease the impact of the disease and ultimately strengthen the CAF.

MATERIALS AND METHODS

A search of systematic reviews and meta-analyses was conducted to determine the efficacy of PRP injections in treating knee OA. The Scopus database, PubMed database, and Omni academic search tools were scoped for relevant publications. English literature, published up to and including March 2023, that investigated only clinically randomized controlled trials (RCTs) was eligible for inclusion. The results of network meta-analyses were investigated and summarized independent of reviews and non-network meta-analyses.

RESULTS

A total of 225 unique systematic reviews and meta-analyses were initially identified, of which 39 publications, including 7 network meta-analyses, adhered to the defined inclusion and exclusion criteria. PRP was found to significantly alleviate symptoms of pain based on the visual analog scale and Western Ontario and McMaster Universities Arthritis Index pain scores within the 12-month follow-up. Function, activity, sport, quality of life, and stiffness were additionally determined to generally improve to a greater extent from PRP treatment compared to controls, while adverse effects were minor and temporary. PRP placed in the top 3 in 9 reported surface under the cumulative ranking curves, while individually reported rankings of leukocyte-poor and leukocyte-rich PRP both placed in the top 4. The clinical recommendations made were generally positive, with 17 publications acknowledging the benefits of PRP, 3 supporting possible efficacy, and an additional 8 recommending that it be an option for the conservative treatment of knee OA.

CONCLUSION

The results of this review support the efficacy of PRP for relieving symptoms of pain and improving function, stiffness, and quality of life for patients experiencing knee OA within 12 months. As a result, leukocyte-poor-PRP could be considered for members of the CAF with mild to moderate knee OA (Kellgren-Lawrence grades 1-3) to slow the progression of OA and extend the military careers of CAF members. There continues to be a need for future studies to investigate the longer-term effects of PRP to verify sustained benefits at follow-up points greater than 12 months, including findings of improvement in a delayed fashion at the 3- and 6-month timeframe compared to hyaluronic acid treatment.

Infiltration therapy in the context of cartilage surgery

Guideline-based surgical cartilage therapy for focal cartilage damage offers highly effective possibilities to sustainably reduce patients' complaints and to prevent or at least delay the development of early osteoarthritis. In the knee joint, it has the potential to reduce almost a quarter of the arthroses requiring joint replacement caused by cartilage damage. Biologically effective injection therapies could further improve these results. Based on the currently available literature and preclinical studies, intra- and postoperative injectables may have a positive effect of platelet-rich plasma/fibrin (PRP/PRF) and hyaluronic acid (HA) on cartilage regeneration and, in the case of HA injections, also on the clinical outcome can be assumed. The role of a combination therapy with use of intra-articular corticosteroids is lacking in the absence of adequate study data and cannot be defined yet. With regard to adipose tissue-based cell therapy, the current scientific data do not yet justify any recommendation for its use. Further studies also regarding application intervals, timing and differences in different joints are required.