Comparison between platelet-rich plasma injections and hyaluronic acid injections in the treatment of patellar tendinopathies: A randomized trial.

Abstract

Background. As patellar tendinopathies are frequently chronic there has been plenty of research carried out to develop effective treatments, among which platelet-rich plasma (PRP) and hyaluronic acid (HA). Hypothesis. Therefore we aimed to compare the effect after three months following injections of PRP compared with HA injections on patients with a proximal patellar tendinopathy. Methods. 33 sportsmen with chronic proximal patellar tendinopathies were included and randomised into 2 groups and treated respectively with PRP (obtained using an apheresis machine) or HA injections. To assess the evolution of the pathology, algo-functional tests (VISA-P and IKDC) and isokinetic tests were carried out pre-injection, after 6 weeks and after 3 months post-injections. Results. The results of VAS, algometric scores, IKDC scores and VISA-P showed a considerable improvement in the two groups over time (p<0.01), except for the US findings. Isokinetic tests showed significant modifications for the quadriceps in C60 (p=0.01) for the pathological limb only at the end of the follow-up period. VAS associated with isokinetic tests decreased significantly for all contraction modes after three months in the HA group (p<0.05). Correlations showed that there was a significant negative association between VAS and strength in C60, C240 and E30 (p<0.01) only for the PRP group. Conclusion. Both PRP and HA can alleviate the symptoms of proximal patellar tendinopathy in the medium term. However, only PRP leads to a decrease in pain associated with an increase in the strength of the quadriceps.