We studied the value of ultrasound (US) to define shoulder pathology and guide local steroid injection in comparison with a standard injection in the management of the acute painful shoulder.

Seventy consecutive patients with acute shoulder pain were assessed clinically and by US. Patients were randomized to receive either a standard subacromial infiltration of 7mg of betamethasone or a US-guided injection according to the US diagnosis. Follow-up evaluations were performed by an independent assessor who was blinded to the results of the initial US and clinical assessments.

Sixty-seven patients completed the study. Both groups showed a significant reduction in both daytime and night pain compared to baseline. The US injection group had significantly less pain at rest at 2 and 6 weeks (NRS: 1.6 vs 3.3, P<0.005; 3 vs 4.2, P<0.04). The percentage of good responders was significantly higher in US group at 2 weeks, (81% vs 54%, P<0.005) and 6 weeks (64% vs 38%, P<0.05). At 2 and 6 weeks, responder rate and activity pain scores as well as Constant score were in favour of US, though did not reach statistical significance.

Local steroid injection for shoulder pain leads to significant improvements in pain and function for up to 12 weeks. An US examination to define the origin of shoulder pain as well as to guide injection provides significant additional benefits for up to 6 weeks. We recommend routine US examination as part of the management of acute shoulder pain.