Clinical efficacy of ultrasound-guided hyaluronic acid injections in patients with supraspinatus tendon tear

Objectives: To evaluate the clinical efficacy of ultrasound (US)-guided soft tissue adapted biocompatible hyaluronic acid (STABHA) injections in the subacromial-subdeltoid bursa of patients with supraspinatus tendon tear. Methods: In this prospective study, patients with a symptomatic partial-thickness or small full-thickness supraspinatus tendon tear, diagnosed by US, were consecutively enrolled. Patients received one injection at baseline visit and one after 2 weeks and performed rehabilitation therapy. Clinical assessment was performed with visual analogue scale (VAS) for pain, Constant-Murley Scale (CMS), and patient reported efficacy on a 0-4 Likert scale. Patients were examined at baseline, at week 2 and at week 12. Results: Thirty patients were enrolled. Sixteen (53.3%) and 19 (63.3%) patients reported significant improvement at week 12 in pain and function, respectively. Reduction in VAS pain was statistically significant both at week 2 and at week 12 in comparison with baseline visit (mean-difference -27.2 and -36.8, respectively, p<0.01). The same trend was observed with CMS (mean-difference 17.7 and 19.8, respectively, p<0.01). At week 12, 18 patients (60.0%) reported a subjective improvement. At week 12, in non-responders (n=14) US detected inflammatory changes and/or progression of tendon tear in 7 (50.0%) patients and no relevant changes in 7 (50.0%). Conclusions: US-guided STABHA injections followed by rehabilitation therapy were found effective in improving both pain and shoulder function at the 12-week follow-up. In half of the non-responders, US allowed the detection of US findings responsible for treatment failure.