BACKGROUND: Platelet-rich plasma (PRP) and hyaluronic acid (HA) are injectable treatments for knee osteoarthritis. The focus of previous studies has compared their efficacy against each other as monotherapy. However, a new trend of combining these 2 injections has emerged in an attempt to have a synergistic effect.
PURPOSE: To systematically review the clinical literature examining the combined use of PRP + HA.
DESIGN: Systematic review.
METHODS: A systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using PubMed and Embase. The following search terms were used: knee osteoarthritis AND platelet rich plasma AND hyaluronic acid. The review was performed by 2 independent reviewers who applied the inclusion/exclusion criteria and independently extracted data, including methodologic scoring, PRP preparation technique, HA composition, and patient-reported outcomes (PROs).
RESULTS: A total of 431 articles were screened, 12 reviewed in full, and 8 included in the final analysis: 2 case series, 3 comparative, and 3 randomized studies. Average follow-up was 9 months. The modified Coleman Methodology Score was 38.13 ± 13.1 (mean ± SD). Combination therapy resulted in improved PROs in all studies. Of the comparative and randomized studies, 2 demonstrated that combination therapy was superior to HA alone. However, when PRP alone was used as the control arm (4 studies), combination therapy was not superior to PRP alone.
CONCLUSION: Combination therapy with PRP + HA improves PROs and is superior to HA alone but is not superior to PRP alone.
PRP is superior to the combination with Hyaluronic acid; this is a relatively new and important conclusion.