Evaluation of trunk sway in sit-to-stand motion using a pressure distribution measurement system

Abstract

Evaluation of trunk sway in sit-to-stand motion using a pressure distribution measurement system. Jpn J Compr Rehabil Sci 2012; 3: 6-10. Purpose: The majority of studies investigating sit-tostand (STS) motion have focused on the analysis of motion in the sagittal plane. We conducted a study using a pressure distribution measurement system known as BIG-MAT (BM) to investigate the bilateral asymmetry of STS. Method: Ten healthy men were asked perform STS movements while paying attention to their bilateral symmetry. We recorded the plantar pressure changes for both feet over the course of 15 rounds of STS. Based on the pressure sensitivity diagram obtained from the BM analysis, time-dependent changes in peak load pressure for both the left and right forefoot and hindfoot were evaluated. Results: Temporal bilateral differences in forefoot peak load were below 0.2 s in 50.3 ± 12.8% of subjects, more than 0.2 s in 45.0 ± 14.1% of subjects, and the peak itself was absent in in 4.0 ± 0.5% of subjects. Conclusion: Despite subjects attempting to remain aware of bilateral symmetry during STS movement, approximately 50% of STS motions were asymmetric. This study suggested the involvement of movements of the trunk, such as small rotations, lateral bendings, and lateral movements.