Reflection of power DOPPLER activity in the subacromial space on nocturnal pain in patients with rotator cuff tears: a cross-sectional study.

Background: Nocturnal shoulder pain is seen in patients with rotator cuff tears (RCTs). The purpose of the present study was to determine whether Doppler ultrasound parameters predict the intensity of nocturnal pain in patients with RCTs.

Methods: A total of 60 patients with RCTs were included. Doppler ultrasound parameters (peak systolic velocity in the anterior humeral circumflex artery, Doppler activity in the glenohumeral joint and subacromial space [SAS]) and clinical parameters were examined. For the presence of nocturnal pain, the clinical parameters were compared with and without nocturnal pain. For the intensity of the nocturnal pain, a multivariate analysis of clinical parameters and nocturnal pain intensity was performed.

Results: In all, 39 patients (65%) reported nocturnal pain, and the mean pain intensity was 47.0 (standard deviation, 26.0) on the visual analog scale. In nocturnal pain presence analysis, Doppler activity in the SAS showed significant associations (P < .001). In nocturnal pain intensity analysis, Doppler activity in the SAS and diabetes showed significant associations (P < .001, P = .01, respectively).

Conclusion: Doppler activity in the SAS emerges as an independent factor associated with the presence and intensity of nocturnal pain in patients with RCTs. Our findings may provide a basis for further exploration and refinement of treatment strategies.