Exploring the effect of a second closely-timed infiltration of platelet-rich plasma to treat jumper's knees

Abstract

Some clinical series have evaluated the effect of platelet-rich plasma (PRP) in the treatment of jumper's knee. Although it is possible that a single infiltrative administration may prove to be an effective treatment for this indication, most of the existing studies evaluated the effects of 2 or 3 successive infiltrations. The aim of this study was to evaluate whether 2 infiltrations of PRP proves more effective than a single treatment. Twenty patients suffering from chronic jumper's knee were enrolled into our prospective and randomized study and split into two randomized groups (1 or 2 infiltrations of PRP, respectively). The 3-month follow-up evaluation consisted of VAS, IKDC and VISA-P scores, along with algometer, isokinetic and ultrasounds evaluations. After 1 year, subjects were contacted to define their functional evolution. The concentration of the PRP used for each infiltration was similar in both groups, and contained no red or white cells. Results revealed no difference in treatment efficacy between the groups. The comparison between 1 or 2 infiltrations of PRP did not reveal any difference between the 2 groups at short to mid term. A second closely-timed infiltration of PRP to treat jumper's knees is not necessary to improve the efficacy of this treatment in the short term.