Gait analysis in a challenging environment differentiates between fallers and nonfallers among older patients with peripheral neuropathy

Objective: To identify differences in gait based on fall history among a group of older subjects with peripheral neuropathy (PN) in 2 environments: standard (SE) (smooth surface, normal lighting) and challenging (CE) (irregular surface, low lighting). Design: Observational, case-control study of PN subjects with and without a history of falling in the previous year. Setting: A biomechanical laboratory. Participants: Forty-two subjects (mean age, 64.7 +/- 9.8y; 20 [47.6%] women), including 22 (52.4%) with a history of at least I fall in the previous year. Intervention: Subjects walked in the SE and CE while kinematic data were obtained. Main Outcome Measures: Step width variability, step time variability, step width-to-step length ratio, step length, and step time and speed (with step length and speed normalized for height) in the SE and CE. Results: In the SE, gait parameters of subjects with and without a history of falls did not differ significantly. However, in the CE, subjects with a history of falls had increased step time variability (P=.001). Moreover, significant interactions between environment and fall status were identified: in the CE, subjects with a history of falls had greater increases in step time variability (P=.010) and step width-to-step length ratio (P=.009) and greater decreases in step length (P=.007) and speed (P=.045) than did subjects with no fall history. Conclusions: Analysis of gait in the CE and adjustment to the CE from the SE effectively identified gait characteristics associated with falls in an older PN population, whereas analysis of gait in the SE did not. PN-associated gait dysfunction is more sensitively detected on an irregular rather than on a flat surface.