Differences in Coracohumeral Distance Between the Symptomatic and the Asymptomatic Shoulder in Patients With Unilateral Shoulder Pain and in Healthy Participants: A Cross-Sectional Study

The aim of this study was to analyze whether differences in the coracohumeral distance (CHD) exist between the symptomatic and the asymptomatic shoulder in patients with subacromial pain syndrome and compare with the shoulder of control participants. This was a cross-sectional, observational study. A sample comprising 62 participants with subacromial pain syndrome was recruited from 3 different primary care centers. The CHD was determined from standardized ultrasonography measures performed on both shoulders at 0° and 60° of shoulder abduction, whereas the dominant arm was measured for the control participants. Statistically significant differences in CHD at 0° and 60° were found between the symptomatic and control shoulders ( P  = .011/ P  = .002) and between the contralateral asymptomatic shoulder and controls ( P  = .026/ P  = .007). We found differences in CHD at 0° and 60° of shoulder elevation between both the affected and the nonaffected shoulders when compared with healthy shoulders. These results suggest that CHD may be a contributing factor in chronic shoulder pain.