Relations of Stiff Shoulders with Deep Hemodynamics Values

Abstract

Poor circulation is considered to be a cause of stiff shoulders, but there have been no studies on deep hemodynamics and the subjective estimation/palpation of stiff shoulders. We evaluated the relationship between deep hemodynamics and the degree of the subjective estimation/palpation of stiff shoulders by near-infrared spectrophotometry.
The subjects were 146 patients who visited our center and 23 healthy volunteers. Deep hemodynamics (tissue oxygen saturation: StO₂, total hemoglobin concentration: total Hb) was measured in the scapular region of the bilateral shoulders using a deep hemodynamics measurement system (PSA-IIIN, Biomedical Science), and its relationship with the severity of the subjective estimation of stiff shoulders (5-grade rating) and that of palpation (4-grade rating) was evaluated. Deep hemodynamic values were affected by the body mass index (BMI) that is highly correlated with subcutaneous fat thickness. Therefore, analysis was performed in 70 patients and 8 healthy volunteers with BMI of 20-24 that does not affect hemodynamic values. Compared with the healthy volunteers, patients who reported marked shoulder stiffness showed a significant decrease in total Hb, and that who reported shoulder stiffness showed a significant decrease in StO₂. On the other hand, compared with the healthy volunteers, patients with marked shoulder stiffness observed by palpation showed significant decreases in both StO₂ and total Hb; the decreases were more marked with more marked stiffness. These results suggested that deep hemodynamics is a diagnostic parameter of stiff shoulders.