Objective Steroid injections are common after an ultrasound-guided puncture and lavage (UGPL) of calcific tendonitis of the rotator cuff. However, steroids may prevent calcification resorption and negatively affect tendon healing. Our study was designed to determine whether saline solution was non-inferior to steroids in the prevention of acute pain reactions in the week following UGPL.

Methods This was a randomised, double-blinded, controlled non-inferiority trial with 12-month follow-up. We included 132 patients (66 in each group) with symptomatic calcification measuring more than 5 mm. Patients received 1 mL of saline or steroid (methylprednisolone 40 mg) in the subacromial bursa at the end of UGPL. Primary outcome was the maximal pain during the week following the procedure with a prespecified non-inferiority margin of 10 mm (0–100 visual analogue scale). Secondary outcomes included pain at rest and during activity, function (disabilities of the arm, shoulder and hand score) and radiological evolution of the calcification over the 12-month follow-up.

Results The estimated mean difference in the first week’s maximal pain between these two groups was 11.76 (95% CI 3.78 to 19.75). Steroids significantly improved VAS pain at rest and during activities, as well as function at 7 days and 6 weeks. They did not change the rate of calcification resorption, which occurred in 83% and 74% of patients at 12 months in the saline and steroid groups.

Conclusion Non-inferiority of saline when compared with steroids could not be established. However, steroid injection improved pain in the 6 weeks following the procedure, and function in the 3 months after, with no significant effect on calcification resorption.

Trial registration number NTC02403856.