Corticosteroids versus platelet-rich plasma injections for knee osteoarthritis: Where is there more evidence? A systematic review of 60 years of literature.

BACKGROUND

Corticosteroid (CS) injections are often recommended by international societies for knee osteoarthritis (OA) treatment, but platelet-rich plasma (PRP) has shown higher safety and efficacy in comparative analyses. Despite this, PRP use is often not endorsed by scientific societies due to perceived insufficient body of evidence. This study aims to quantify clinical data documenting CS and PRP intra-articular injections for knee OA.

METHODS

A systematic review of the literature was conducted on CS and PRP injections for knee OA. The search, performed in March 2024, used PubMed, Cochrane, and Web of Science databases, following PRISMA and Cochrane guidelines. Data collected included publication trends, number of articles, patients evaluated, and study designs documenting CS or PRP injections.

RESULTS

Of 16,979 records, 356 studies were analyzed, covering 24,435 knee OA patients. Both treatments showed an increasing publication trend, with PRP surpassing CS in 2020. The analysis included 9,322 CS patients and 15,113 PRP patients. Among CS studies, there were 103 RCTs with 5,478 patients, 18 comparative studies with 1,095 patients, and 31 case series with 2,749 patients. Among PRP studies, there were 119 RCTs with 6,028 patients, 33 comparative studies with 2,011 patients, and 72 case series with 7,074 patients.

CONCLUSIONS

PRP injections for knee OA have been documented in more studies and in larger patient numbers compared with CS injections. The higher number of high-level trials for PRP, combined with the lower safety and efficacy documented for CS by previous meta-analyses directly comparing the two products, strongly suggests reconsidering current guidelines that favor CS, highlighting PRP's body of evidence and the potential role in the effective and safe treatment of knee OA.