Effects of supplementing extracorporeal shockwave therapy to hyaluronic acid injection among patients with rotator cuff lesions without complete tear: a prospective double-blinded randomized study

Abstract

Background: The study investigates the combined efficacy of subacromial hyaluronic acid (HA) injections and extracorporeal shockwave therapy (ESWT) in managing rotator cuff lesions without complete tears. Materials and methods: Eligible patients were randomized into three groups: 3 HA injections combined with 2 sham ESWT (HA), 3 HA injections combined with 1 ESWT and 1 sham ESWT (HA + 1 ESWT), or 3 HA injections combined with 2 ESWT (HA + 2 ESWT) with an allocation ratio of 1:1:1. Visual Analogue Scale (VAS), Constant–Murley Score (CMS), range of motion (ROM), and muscle power of shoulder abduction (MP) were assessed pre-intervention and at 1, 3, 6, and 12 months post-initial HA injection. Shoulder magnetic resonance imaging (MRI) was conducted before and twelve months after the intervention. Results: All pertinent parameters showed no significant between-group differences at baseline but demonstrated significant within-group improvement throughout the study. The HA + 1 ESWT group demonstrated superior improvements in MP (P=0.011) and CMS (P=0.018) at 1 month, and in MP (P=0.014) and CMS (P=0.005) at 6 months, compared to the HA group. The HA + 2 ESWT group showed greater improvements in FF (P=0.027), IR (P=0.019), and SROM (P=0.025) at 1 month, and in ABD (P=0.022) at 6 months, compared to the HA group. Notably, the HA + 2 ESWT group exhibited greater improvements in FF (P=0.013), IR (P=0.019), and SROM (P=0.025) at 1 month, and in FF (P=0.007) at 3 months, than the HA + 1 ESWT group. Moreover, no deterioration in tendinopathy grading or tear status occurred in the HA + 1 ESWT group on MRI scans. Conclusion: ESWT provides additional benefits when combined with HA injections for patients with rotator cuff lesions lacking complete tears.