Comparison of Peritendinous Hyaluronan Injections Versus Extracorporeal Shock Wave Therapy in the Treatment of Painful Achilles' Tendinopathy: A Randomized Clinical Efficacy and Safety Study

Abstract

ObjectiveTo compare the safety and efficacy of hyaluronan (HA) injections with standard extracorporeal shock wave therapy (ESWT) in the treatment of painful midportion Achilles' tendinopathy. DesignMultinational, prospective, randomized controlled, blinded-observer trial. SettingAmbulatory care. ParticipantsAdults (N=62) with Achilles' midportion tendinopathy for ≥6 weeks and a pain score of at least 40mm (Huskisson visual analog scale [VAS], 100mm) were randomized, and 59 were analyzed in the intention-to-treat data set. There were no withdrawals because of adverse effects. InterventionsTwo peritendinous HA injections versus 3 ESWT applications at weekly intervals. Main Outcome MeasuresPrimary efficacy criterion was changed from the Victorian Institute of Sports Assessment–Achilles' questionnaire (VISA-A) score to the percent change in pain (VAS) at 3 months posttreatment, compared with baseline values. Main secondary parameters were VISA-A, Clinical Global Impression (CGI), and clinical parameters. ResultsHA treatment provided a clinically relevant improvement in Achilles' midportion tendinopathy. A large superiority of the HA group, compared with ESWT application, was observed for percent change in pain (VAS), and this superiority was proven to be statistically significant (Mann-Whitney statistic [MW]=.7507 with P=.0030 lower than required α=.025 significance level 1-sided; Mann-Whitney U test) at 3 months posttreatment. Similar findings for HA were also observed at 4 weeks (MW=.6425, P=.0304) and 6 months (MW=.7172, P=.0018). Advantage of HA treatment was confirmed by VISA-A questionnaire, CGI, and clinical parameters. Ten adverse events, 4 in the HA group and 6 in the ESWT group, were reported, but none were classified as serious. ConclusionsTwo peritendinous HA injections showed greater treatment success in Achilles' midportion tendinopathy compared with standard ESWT.