Design, Validity, and Reliability of a New Test, Based on an Inertial Measurement Unit System, for Measuring Cervical Posture and Motor Control in Children with Cerebral Palsy

Abstract

Objective: The aim of this study was to design and propose a new test based on inertial measurement unit (IMU) technology, for measuring cervical posture and motor control in children with cerebral palsy (CP) and to evaluate its validity and reliability. Methods: Twenty-four individuals with CP (4–14 years) and 24 gender- and age-matched controls were evaluated with a new test based on IMU technology to identify and measure any movement in the three spatial planes while the individual is seated watching a two-minute video. An ellipse was obtained encompassing 95% of the flexion/extension and rotation movements in the sagittal and transversal planes. The protocol was repeated on two occasions separated by 3 to 5 days. Construct and concurrent validity were assessed by determining the discriminant capacity of the new test and by identifying associations between functional measures and the new test outcomes. Relative reliability was determined using the intraclass correlation coefficient (ICC) for test–retest data. Absolute reliability was obtained by the standard error of measurement (SEM) and the Minimum Detectable Change at a 90% confidence level (MDC90). Results: The discriminant capacity of the area and both dimensions of the new test was high (Area Under the Curve ≈ 0.8), and consistent multiple regression models were identified to explain functional measures with new test results and sociodemographic data. A consistent trend of ICCs higher than 0.8 was identified for CP individuals. Finally, the SEM can be considered low in both groups, although the high variability among individuals determined some high MDC90 values, mainly in the CP group. Conclusions: The new test, based on IMU data, is valid and reliable for evaluating posture and motor control in children with CP.

HeadUp: A Low-Cost Solution for Tracking Head Movement of Children with Cerebral Palsy Using IMU

“…This means the lower part of the body will be stationary and will not affect head movement, as a result only one IMU has been used to capture the head movement. Additionally, different studies showed that one IMU can capture the full head orientation [24,[51][52][53].…”

“…The main contribution of this paper is the use of a custom built and low-cost sensor for capturing head movement of children with CP in the age range of 2 to 5 years. Most of the research in the literature target older children (5-12 years) with either higher CP levels such as level I or II, where the child already has better motor ability and reasonably good head control [23][24][25]. The paper shows the application of a low-cost engineering solution to capture clinically viable data which allows clinical professionals and physiotherapists to get a better understanding of the active range of head movement for children with CP.…”

“…)[24,54,55] • Case 1: sit still without any movement (Natural).• Case 2: dorsal extension and ventral flexion. • Case 3: right lateral flexion and left lateral flexion.…”

Can Wearable Inertial Measurement Units Be Used to Measure Sleep Biomechanics? Establishing Initial Feasibility and Validity

“…Wearable accelerometers have long been used in research to record body segment orientation and motion [ 1 , 2 , 3 ]. Over the past decade, Inertial Measurement Units (IMUs) have become a research tool of choice for field-based quantification of kinematics and joint angles [ 4 , 5 ]. By combining the outputs of the gyroscope, accelerometer, and magnetometer componentry, IMUs are able to capture dynamic movement data accurately and reliably [ 6 ].…”