Systemic effects after local injection of platelet-rich plasma: a prospective randomized study

Abstract Background Platelet-rich plasma (PRP) is widely utilized in the treatment of sports injuries. However, potential systemic effects after localized PRP injection are unclear at present.Design: prospective randomized study Methods Twenty-four Taiwanese male athletes with tendinopathy were randomized into a PRP group (n = 13) or a saline group (n = 11).Results The results showed no significant differences in serum levels of growth hormone, insulin-like growth factor-1, insulin-like growth factor-binding protein 3, vascular endothelial growth factor, platelet-derived growth factor-BB, or serum substance P between the two groups at baseline, nor at 1, 2, or 7 days after intervention. However, a significant decrease in the serum substance P level 1 and 7 days after PRP injection was observed. Regarding urinary concentrations of metabolites of anabolic androgenic steroids (AAS), no between-group differences at baseline, nor at 1, 2, or 7 days after intervention, were observed. Conclusions Our study failed to observe significant surge of serum anabolic molecules and urinary excretion of anabolic AAS metabolites after PRP injection. Trial registration with ClinicalTrials.gov: NCT04456907