Measurement of Pelvic Retroversion During Hip Flexion: Evaluation With Accelerometers

Abstract

Objective: To quantify pelvic retroversion during clinical evaluation of hip flexion with accelerometers and to verify the reliability of these sensors to measure hip flexion. Methods: An accelerometer was positioned laterally in the pelvis to measure pelvic retroversion. Another accelerometer was positioned anteriorly on the thigh to evaluate hip flexion amplitude. The evaluations were performed with volunteers in supine position by three raters. For evaluation of pelvic retroversion, the mean ± SD (minimum-maximum) was calculated. Reliability of the accelerometer between raters was determined by intraclass correlation coefficients (ICC). The linear correlation coefficient between hip flexion was determined by using goniometer and accelerometer. Results: The mean pelvic retroversion was 7.3° ± 0.93° (6°-11°) in the clinical limit of the hip range of motion, which was 106.25° ± 10.46° (93°-130°). The ICC between two raters were 0.60, 0.71 and 0.74 (goniometer) and 0.46, 0.71 and 0.83 (accelerometer). The linear correlation between hip flexion measurements with goniometer and accelerometer was 0.87. Conclusion: During clinical evaluation of the final range of hip flexion, there was an associated pelvic movement of approximately 7.3º. Accelerometers have proven to be reliable for measurement of hip flexion. Level of Evidence III, Study of nonconsecutive patients with no gold reference standard applied uniformly.

GonioPi: Towards Developing a Scalable, Versatile, Reliable and Accurate Handheld-Wearable Digital Goniometer

“…A study that focused on measuring pelvic retroversion during hip flexion used two MPU-6050 IMU sensors connected an Arduino microcontroller that were attached to elastic Velcro-like straps recorded an average angle of 7.30 degrees which is considered reliable for pelvic retroversionwith this result the researchers concluded that the MPU-6050 IMU sensor was considered reliable when performing the ROM Test of hip flexion [11]. The device, however, cannot be considered versatile or scalable.…”

“…Previous attempts to develop wearable digital goniometers using sensor technology are neither versatile nor scalable. These studies only considered some of the 34 different ROM tests [6] such as wrist flexion and extension, forearm supination and pronation, radial deviation, and ulnar deviation [7,8]; elbow joint [9 ,10]; hip flexion [11]; and knee flexion and extension [12]. There is no study which attempted to develop a scalable and versatile digital goniometer -one that can support all possible ROM tests in multiple different positions on people with varying heights, weights, and BMI categories.…”