Anthropometric Parameters for Sensor Placement in Wearable Technologies at the Trunk

Abstract

Background: Posture education is an essential part of the rehabilitation in musculoskeletal disorders of the spine. Sensor technologies may support patients in offering feedback on posture in rehabilitation settings or during everyday life activities (home, work, etc.). The aim of this study was to inform developers of wearable sensor technologies for the trunk on the correct position of the sensors. Methods: In this cross sectional study, bony landmarks of the spinous processes from C7, T4, T12, L1, L5, and Spinae Iliacae Posterior Superior (SIPS) were palpated and marked in healthy persons. Intervertebral distances were measured by means of a flexible ruler. T-shirt size was determined by asking the patient to try on an available set of T-shirts and choose the best fitting size. Results: Sixty healthy persons (age 40.57, ± 14.55) participated in the study. This study resulted in an overview of intervertebral distances in persons with different anthropometric characteristics. One-way ANOVA showed that there were significant differences between C7-T4 and T4-T12 for persons with different T-shirt sizes (p=0.0144 and p=0.0042), for persons with different trunk length (p=0.0062 and p=<0.0001), and for persons with different full body length (p=0.0109 and p=0.0029). Conclusion: It can be concluded that intervertebral distances in the thoracic and lumbar spine are different for healthy individuals with different trunk length and different body lengths. For the thoracic spine, the intervertebral distances are also different in persons with different T-shirt sizes. For wearable textiles, a sensor position is that is customized to the anthropometric measurements of the user is advocated.