Three-dimensional primary and coupled range of motions and movement coordination of the pelvis, lumbar and thoracic spine in standing posture using inertial tracking device.

ABSTRACT

Evaluation of spinal range of motions (RoMs) and movement coordination between its segments (thorax, lumbar, and pelvis) has clinical and biomechanical implications. Previous studies have not recorded three-dimensional primary/coupled motions of all spinal segments simultaneously. Moreover, magnitude/direction of the coupled motions of the thorax/pelvis in standing posture and lumbopelvic rhythms in the frontal/transverse planes have not been investigated. This study, hence, used an inertial tracking device to measure T1, T5, T12, total (T1-T12) thoracic, lower (T5-T12) and upper (T1-T5) thoracic, lumbar (T12-S1), and pelvis primary and coupled RoMs as well as their movement coordination in all anatomical planes/directions in twenty-two healthy individuals. RoMs were statistically compared between the anatomical planes and spinal segments as well as with available data in the literature. The spine had different primary RoMs in different planes/directions (flexion lumbar 55.4 ±â€¯12.4°, pelvis 42.8 ±â€¯21.6°, and T1-T12 thoracic 19.9 ±â€¯6.4°, extension lumbar 23.4 ±â€¯10.1°, thoracic 11.7 ±â€¯3.4°, and pelvis 10.2 ±â€¯6.4°, left/right lateral bending thoracic 24.5 ±â€¯7.4°/26.5 ±â€¯6.1°, lumbar 16.4 ±â€¯7.2°/18.3 ±â€¯5.7°, and pelvis 11.0 ±â€¯4.4°/9.3 ±â€¯6.2°, and left/right axial rotation thoracic 33.5 ±â€¯10.0°/37.1 ±â€¯11.7°, pelvis 31.6 ±â€¯12.5°/27.2 ±â€¯12.0° and lumbar 7.5 ±â€¯4.5°/9.2 ±â€¯7.3°). Pelvis, lumbar and thoracic spine had different/varying contributions/rhythms to generate total trunk (T1) movement, both within and between planes. Pattern of the coupled motions was inconsistent between subjects but side bending was generally associated with twisting to the same side at the thoracic spine and to the opposite side at the lumbar spine.