Precision of an Inertial System to Evaluate the Finger Tapping Test in Women with Fibromyalgia

This study investigates the precision of an inertial measurement unit (IMU) in evaluating the Finger Tapping Test (FTT) to differentiate motor control competencies in women with fibromyalgia, a clinical population characterized by motor impairments.

The sample consisted of 240 FTT trials collected from 20 women, half of whom were diagnosed with fibromyalgia (F = 46.4 ± 12.714; C = 45.9 ± 12.950). Procedures consisted of participants completing FTT while data were collected from a high-speed camera and an IMU for linear acceleration and angular velocity, respectively. Analyses employed the Bland-Altman technique with both parametric and bootstrap-derived limits of agreement and intraclass correlation coefficients to assess levels of agreement between traditional and IMU-derived methods.

The results showed a strong agreement at subject×hand aggregation for the number of taps (RPC = 4.3 and ICC = 0.94) and for the inter-tap interval (RPC = 0.02 and ICC = 0.89), indicating minimal differences between measurements and demonstrating the potential for highly sensitive motor function assessment using an IMU.

These findings suggest that IMU technology can effectively detect subtle aspects of motor control, supporting its use in exercise, rehabilitation, and clinical physiotherapy settings, including functional training, adapted rehabilitation exercises, and home-based monitoring for fibromyalgia. This approach offers detailed insights into subtle motor impairments, emphasizing its value for both clinical and exercise applications.