Background: Glenohumeral subluxation (GHS) is reported in as many as 81% of patients with stroke, which presents considerable challenges for individuals involved in stroke rehabilitation. During rehabilitation, the joint head of the glenohumeral joint was maintained in the socket by wearing a GHS shoulder sling. To ensure that the glenohumeral joint head is in the socket, an orthosis is required to automatically adjust the degree of orthosis according to the degree of GHS. However, there is currently no wearable method for assessing the degree of GHS. This study aims to develop a GHS assessment method for patients with stroke that has the potential to be integrated into a wearable shoulder sling.
Methods: To that end, we developed a GHS assessment method for patients with stroke based on a ﬂex sensor, which has the potential to be integrated into a wearable shoulder sling. Seventeen patients with stroke in a diverse degree of GHS were recruited for the study. The curvature diﬀerence of the aﬀected shoulder in the subluxation and reduction states was collected by ﬂex sensor to calculate the degree of GHS (AGTD). Meanwhile, the GHS degree, calculated as the acromion–greater tuberosity distance di.ﬀerence (AGTD) of the aﬀected and unaﬀected shoulder, was measured by the gold-standard radiographic assessment.
Results: The GHS degree measurement by ﬂex sensor and radiographic assessment has strongly correlated (r = 0.92, p < 0.01). The relationship of GHS degree measured by radiographic assessment (AGTD) and ﬂex sensor (AGHS) is linear according to an interpolating curve with an equation: AGHS = 0.767AGTD + 1.781 (R2 = 0.84, RMSE = 1.61). The method has excellent reliability with R = 0.87, CI = 95% for assessment of GHS degrees.
Conclusions: The proposed method demonstrates good performance, is wearable, easy to use, and allows automatic measurements, so as to be a valuable method to assessment of GHS.