The seated position is the most frequent and fundamental for patients with Spinal Cord Injury (SCI). There are tests for clinically assessing seated postural control in SCI, most of them rely on distance related parameters. However, clinical assessment of trunk control in SCI is not enough sensitive to detect and/or describe a possible improvement. Hence, there is a need for practical, objective and reliable assessment tools to demonstrate the efficacy of different interventions in clinical practice. Therefore our objective was to establish the reliability of distance related measures obtained from inertial sensors (IMUs) to assess trunk control in SCI subjects.

A cross-cutting study was performed where 15 non SCI subjects and 22 SCI subjects who fulfilled inclusion criteria were recruited. After signature of informed consent, there was held a concurrent application of the trunk control test (TCT) and the instrumental assessment (using IMUs attached to head and trunk of subjects) with repeated measures three times of static and dynamic control selected items, in an interleaved and random manner. IMUs 3D orientation was obtained during all time. Distance related parameters on transverse plane were obtained after applying IMUs 3D orientation to a biomechanical model of head and trunk segments. Dimensions were normalized to body segments. One hundred twenty-four distance related measures were calculated. Test-retest reliability was measured by intraclass correlation coefficients (ICC) of items with repeated measures.

High reliability (ICC>0.5) was found on 10 distance related measures in both areas of static and dynamic equilibrium of TCT, measured on both the head and the trunk of SCI and non SCI subjects.

It was demonstrated that the IMU usage has high reliability when measuring distance related parameters of static and dynamic control of the trunk.