Introduction Chronic Achilles tendinopathy occurs frequently and is very hard to treat. The disease involves local degeneration of tendon tissue, of which regeneration may be improved by injecting platelet-rich plasma (PRP), an increasingly used therapy for releasing growth factors into degenerative tendon. However, high-quality randomised clinical trials on this topic are lacking. The aim of this study was to evaluate the effect of a PRP injection in patients with chronic Achilles tendinopathy.

Methods In this stratified, block randomised, double-blind, placebo-controlled trial at single center 54 patients aged 18–70 years were randomised in two treatment groups. Next to an eccentric training program the patients received a blinded injection containing either PRP group or saline (placebo group). Primary outcome, the objective and validated Victorian Institute of Sports Assessment-Achilles (VISA-A) score, was assessed and ultrasound examination was performed at baseline and all follow-up appointments.

Results After randomisation into the PRP group (n=27) and the placebo group (n=27) there was a complete follow-up. After one year, the mean VISA-A score improved in both the PRP-group and the placebo group. There was no significant difference in increase between both groups (adjusted between-group difference, 5.5; 95% CI, −4.9 to 15.8, p=0.292). Ultrasonographic tendon structure improved significantly in both groups, but not significant different between both groups (adjusted between-group difference, 1.2 %, 95% CI, −4.1 to 6.6, p=0.647)

Conclusion One-year follow-up analysis of the world’s first randomised controlled trial showed no evidence for the use of platelet-rich plasma injection in chronic Achilles tendinopathy. These findings are in line with our 6 months results (De Vos et al JAMA 2010).