Shoulder pain and subluxation after stroke: Correlation or coincidence?

Objective. Few studies have concomitantly examined shoulder subluxation and other potential causes of shoulder pain in persons who have had a stroke. This study explores whether shoulder pain after stroke is related to shoulder subluxation, age, limitations in shoulder range of motion, and upper extremity motor impairment. Method. Shoulder pain was measured with a visual analog scale in 20 subjects admitted to a rehabilitation hospital within 6 weeks of onset of their first stroke. Degree of shoulder pain was correlated with vertical, horizontal, and total asymmetries of glenohumeral subluxation; age; shoulder flexion, abduction, and external rotation; and the upper extremity subscore of the Fugl-Meyer Motor Assessment. Results. Shoulder pain after stroke was not correlated with age (r(k) = .019, p = .916); vertical (r(k) = .081, p = .324), horizontal (r(k) = .126, p = .241), or total asymmetry (r(k) = -.098, p = .288); shoulder flexion (r(k) = .049, p = .390) or abduction (r(k) = -.074, p = .337); or Fugl-Meyer scores (r(k) = -.123, p = .257). In contrast, shoulder pain was strongly correlated with degree of shoulder external rotation (r(k) = -.457, p = .006). Conclusion. These results do not support a strong relationship between shoulder subluxation and pain after stroke. Appropriate precautions should be taken to prevent range of motion limitations that may result in shoulder pain.