Background: Home-exercise is commonly prescribed for rehabilitation of the shoulder following injury. There is a lack of technology available to monitor if the patient performs the exercises as prescribed.
Purpose: The purpose of this study was to investigate the validity of using three dimensional (3D) gyroscope data recorded with the Bandcizer™ sensor to differentiate between three elastic band exercises performed in the shoulder joint: abduction, flexion, and external rotation.
Design: Concurrent validity study.
Methods: This study was performed over two phases. In the first phase, 20 subjects performed three sets of 10 of shoulder abduction, external rotation and flexion exercises with a Thera-Band mounted with a Bandcizer, while supervised by a physical therapist. The Bandcizer has an inbuilt three-dimensional gyroscope, capable of measuring angular rotation. Gyroscope data were analyzed in Matlab, and a one-way ANOVA was used to test for significant differences between each of the three exercises. An algorithm was then created in Matlab based on the exercise-data from the gyroscope, to enable differentiation between the three shoulder exercises. Twenty new subjects were then recruited to cross-validate the algorithm and investigate if the algorithm could differentiate between the three different shoulder exercises.
Results: A blinded assessor using the Matlab algorithm could correctly identify 56 out of 60 exercise sets. The kappa agreement for the three exercises ranged between 0.86-0.91.
Conclusion: The ability to differentiate between the home exercises performed by patients after shoulder injury has great implications for future clinical practice and research. When home exercises are the treatments-of-choice, clinicians will be able to quantify if the patient performed the exercise as intended. Further research should be aimed at investigating the feasibility of using the Bandcizer™ in a home-based environment.
Word count: 2429.
Level of evidence: 2.
Keywords: Adherence; Bandcizer; gyroscope; rehabilitation.