Daily stepping in individuals with motor incomplete spinal cord injury

Background. In individuals with motor incomplete spinal cord injury (SCI), ambulatory function determined in the clinical setting is related to specific measures of body structure and function and activity limitations, although few studies have quantified the relationship of these variables with daily stepping (steps/day). Objective. The aim of this study was to quantify daily stepping in ambulatory individuals with SCI and its relationship with clinical walking performance measures and specific demographics, impairments, and activity limitations. Design. A cross-sectional study was performed to estimate relationships among clinical variables to daily stepping in self-identified community versus non-community (household) walkers. Methods. Average daily stepping was determined in 50 people with chronic, motor incomplete SCI. Data for clinical and self-report measures of walking performance also were collected, and their associations with daily stepping were analyzed using correlation and receiver operating characteristic (ROC) analyses. Relationships between daily stepping and the measures of demographics, impairments, and activity limitations were identified using correlation and regression analyses. Results. The ROC analyses revealed a significant discriminative ability between self-reported community and non-community walkers using clinical gait measures and daily stepping. Stepping activity generally was low throughout the sample tested, however, with an average of approximately 2,600 steps/day. Knee extension strength (force-generating capacity) and static balance were the primary variables related to daily stepping, with metabolic efficiency and capacity and balance confidence contributing to a lesser extent. Limitations. The small sample size and use of specific impairment-related measures were potential limitations of the study. Conclusions. Daily stepping is extremely limited in individuals with incomplete SCI, with a potentially substantial contribution of impairments in knee extension strength and balance.