Effects of hypertonic dextrose injection in chronic supraspinatus tendinopathy of the shoulder: a randomized placebo-controlled trial

Background Rotator cuff lesions are common causes of shoulder pain. Although patients with symptoms caused by chronic rotator cuff tendinopathy can be treated using conservative treatments, some of them may still experience refractory symptoms. Hypertonic dextrose prolotherapy (DPT) may be another treatment choice for these refractory symptoms. Aim The aim of this study was to evaluate the effects of an ultrasound-guided hypertonic dextrose injection for patients with chronic supraspinatus tendinopathy. Design Randomized double-blind placebo-controlled trial. Setting Academic medical center. Population Outpatients patients (N.=31) with chronic supraspinatus tendinopathy and shoulder pain for more than six months. Methods Study group treated with one dose of an ultrasound-guided hypertonic dextrose (20%) injection at the supraspinatus enthesis site, whereas control patients received one dose of 5% normal saline through the same method. The Visual Analog Scale (VAS), Shoulder Pain And Disability Index (SPADI), shoulder active range of motion (AROM) and ultrasonographic thickness and histogram results of the supraspinatus tendon were evaluated before intervention and at two and six weeks after intervention. The outcome differences between the study and control groups were analyzed by using repeated-measures analysis of variance (ANOVA). Results In total, 31 patients completed the study. The study group indicated a significant improvement in the VAS (P=0.001), SPADI scores (P=0.017), shoulder AROM of flexion (P=0.039), and abduction (P=0.043) compared with the control group at two weeks after the injection. However, the effect did not sustain until six weeks after the injection. No differences in the histograms and morphological changes (thickness) were noted before and after injection in both groups. Conclusions This study revealed that the ultrasound-guided hypertonic dextrose injection relieved pain, disability, and improved shoulder AROM for a short period in patients with chronic supraspinatus tendinopathy. Clinical rehabilitation impact For patients with chronic shoulder pain and supraspinatus tendinopathy, ultrasound-guided hypertonic dextrose injections can provide relief from pain, disability, and shoulder range of motion for up to two weeks after intervention.