JMIR Publications

ABSTRACT

Background:

Shoulder pain secondary to rotator cuff tendinopathy (RCT) affects a large proportion of patients in orthopaedic surgery practices. Corticosteroid injections (CSI) are a common intervention proposed for these patients. The clinical evaluation of a response to CSI is usually based only on the patient’s self-evaluation of his function, activity and pain by multiple questionnaires with varying metrologic qualities. Objective measures of upper extremity functions are lacking but wearable sensors are emerging as potential tools to assess upper extremity function and activity.

Objective:

1) Evaluate and compare in patients with RCT convergent validity, test-retest reliability and sensitivity to change of known clinical assessments of shoulder function to wrist-based accelerometers measures and visual analog scales (VAS) of shoulder activity during daily living; 2) Determine the acceptability and compliance of using wrist-based wearable sensors an outcome measure to study the effects of CSI on RCT.

Methods:

38 patients affected by RCT wore wrist accelerometers on the affected side for a total of five weeks. WORC, QuickDASH and clinical examination (range of motion- ROM and strength) were performed the week before the CSI , the day of the CSI , and two and four weeks post CSI. Daily Single Assessment Numeric Evaluation (SANE) and visual analog scales (VAS) were filled by participants to record shoulder pain and activity. Accelerometer data was processed to extract daily upper extremity activity in the form of active time (AT), activity counts (AC) and ratio of low intensity activities (LIA), medium intensity activities (MIA) and high intensity activities (HIA)

Results:

Daily pain measured with VAS and SANE correlated well with the WORC and QuickDASH questionnaires (r = 0.564-0.815) but not with accelerometry measures, amplitude and strength . Daily activity measured with VAS had good correlation with AT (r=0.484). All questionnaires had excellent test-retest reliability at one week before CSI (ICC = 0.883-0.950). Similar reliability was found with ROM and strength, except for abduction strength (ICC = 0.770), ROM in internal rotation (ICC = 0.786) and external rotation (ICC = 0.601). Acceptable reliability was observed with accelerometry (ICC 0.621-0.724), apart from LIA (ICC 0.104). Sensitivity to change was excellent at two- and four-weeks for all questionnaires (Standardized Response Mean, SRM = 1.039-2.094) except for activity VAS (SRM = 0.50). Accelerometry measures had low sensitivity to change at two weeks, but excellent sensitivity at four weeks (SRM = 0.803-1.032).

Conclusions:

Daily pain VAS and SANE have good correlation with validated questionnaires, excellent reliability at one week, and excellent sensitivity to change at two and four weeks. Daily activity VAS and accelerometry derived AT correlate well together. Activity VAS have excellent reliability, but moderate sensitivity to change. Accelerometry measures have moderate reliability and acceptable sensitivity to change at four weeks.