A prospective study of 100 patients with rotator cuff tendinopathy showed no correlation between subacromial bursitis and the efficacy of ultrasound-guided corticosteroid injection

Objectives The objective of this study was to determine whether the presence of subacromial bursitis in patients with rotator cuff tendinopathy (RCT) was associated with a better outcome after ultrasound (US)-guided subacromial corticosteroid injection. Methods A single-center prospective study was performed including patients referred for subacromial injection to manage RCT. At baseline, all patients received an US-guided intra-bursal injection of betamethasone (1 ml). The primary endpoint was reduced pain 3 months (M3) after the procedure: a good responder was defined by a decrease in Visual Analogue Scale pain of more than 30%. Secondary endpoints included functional recovery assessed by the Oxford Shoulder Score (OSS) and clinical success at 6 weeks (W6). We also explored the association between good clinical response and other factors, such as US or X-ray features. Results One hundred patients were included and 49 presented with subacromial bursitis. At M3, 60% of patients (54/100) were considered good responders. The rate of good responders did not differ between the bursitis and non-bursitis groups ( p = 0.6 ). During follow-up, OSS improved over time whether bursitis was present or not. We did not find any US or X-ray features significantly associated with a favorable clinical outcome. Conclusion The presence of subacromial bursitis did not influence clinical outcomes at 3 months post-subacromial injection in patients suffering from RCT. Clinical relevance statement The presence of subacromial bursitis did not influence clinical outcomes at 3 months post-subacromial corticosteroid injection in patients with rotator cuff tendinopathy. For patient management, looking for ultrasonographic signs of bursitis does not appear relevant for the indication of the injection. Key points • Ultrasound-guided subacromial corticosteroid injections led to a significant improvement in 60% of patients suffering from rotator cuff tendinopathy . • The presence of subacromial bursitis was not associated with better improvement at 3 months post-injection . • Except for the Minnesota score referring to job satisfaction, we did not find any baseline clinical, X-ray, or ultrasound characteristics associated with a successful outcome .