Intra-articular Infiltration of Platelet-Rich Plasma versus Hyaluronic Acid in Patients with Primary Knee Osteoarthritis: Preliminary Results from a Randomized Clinical Trial .

Objective  The present study aimed to compare the effects of intraarticular infiltration of platelet-rich plasma with those of hyaluronic acid infiltration in the treatment of patients with primary knee osteoarthritis. Methods  A randomized clinical trial was conducted with 29 patients who received an intraarticular infiltration with hyaluronic acid (control group) or platelet-rich plasma. Clinical outcomes were assessed using the visual analog scale for pain and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire before and after the intervention. In addition, the posttreatment adverse effects were recorded. Categorical variables were analyzed using the chi-square and Fisher exact tests, whereas continuous variables were analyzed using the Student t test, analysis of variance, and the Wilcoxon test; all calculations were performed with the Stats package of the R software. Results  An independent analysis of each group revealed a statistical difference within the first months, with improvement in the pain and function scores, but worsening on the 6 th month after the procedure. There was no difference in the outcomes between the groups receiving hyaluronic acid or platelet-rich plasma. There was no serious adverse effect or allergic reaction during the entire follow-up period. Conclusion  Intraarticular infiltration with hyaluronic acid or platelet-rich plasma in patients with primary knee gonarthrosis resulted in temporary improvement of functional symptoms and pain. There was no difference between interventions.