Kinematics recommendation for balance studies on unstable sitting control

While several types of kinematics have been used to assess unstable sitting control, their contribution to the completion of this task is unknown. The overall goal of this study was to understand the kinematics used to stabilize the trunk in unstable sitting as elicited via a wobble board (WB). The objective was to quantify the kinematics of the WB, pelvis, and trunk in unstable sitting and characterize their relative contributions to task completion. We quantified WB and body kinematics during unstable sitting using posturographic measures on respective three-dimensional angles. A Wilcoxon signed-rank test compared corresponding angles between WB and pelvis, and between WB and trunk. During unstable sitting, the trunk remained upright and was stabilized via WB motion. WB measure values were significantly larger than their corresponding pelvis or trunk values. Future unstable sitting studies should use analyses involving base of support kinematics.