Introduction: The need to identify functional impairment following a brain injury is critical to prevent reinjury during the period of recovery. However, little is known about the effect of concussion on dynamic motor function.
Purpose: The purpose of this study was to examine the effect of concussion on a dynamic motor task under conditions of divided and undivided attention over the course of 28 d.
Methods: Fifteen subjects with concussions (CONC) and 15 uninjured controls (NORM) were observed while walking with undivided attention and while concurrently completing simple mental tasks. The CONC were assessed within 48 h of injury and again at 5, 14, and 28 d postinjury. The NORM were evaluated at the same time intervals. Whole-body motion data were collected to examine displacement and velocity of the center of mass (COM) and the maximum separation between the COM and center of pressure (COP). Three-way repeated-measures mixed-design ANOVA and Tukey post hoc tests were completed to determine differences between group, task, and testing day (P < 0.05).
Results: Several aspects of gait stability were compromised in the CONC group for up to 4 wk after injury. CONC were found to walk significantly slower during dual tasks on all testing days when compared with the uninjured controls. The injured subjects were also found to have greater sway and sway velocity than controls when attention was divided for up to 28 d postinjury.
Conclusion: The findings of this study suggest that concussion may have long-term observable and measurable effects on the control of gait stability.
Motion Analysis Laboratory, Department of Human Physiology, University of Oregon, Eugene, OR
Address for correspondence: Li-Shan Chou, Ph.D., Department of Human Physiology, 1240 University of Oregon, Eugene, OR 97403; E-mail: firstname.lastname@example.org.
Submitted for publication April 2005.
Accepted for publication December 2005.