Malik Raza Naseem, Cote Rachel, Lam Tania
School of Kinesiology and International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
School of Kinesiology and International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada.
J Neurophysiol. 2017 Jan 1;117(1):36-46. doi: 10.1152/jn.00169.2016. Epub 2016 Oct 12.
Skilled walking, such as obstacle crossing, is an essential component of functional mobility. Sensorimotor integration of visual and proprioceptive inputs is important for successful obstacle crossing. The objective of this study was to understand how proprioceptive deficits affect obstacle-crossing strategies when controlling for variations in motor deficits in ambulatory individuals with spinal cord injury (SCI). Fifteen ambulatory individuals with SCI and 15 able-bodied controls were asked to step over an obstacle scaled to their motor abilities under full and obstructed vision conditions. An eye tracker was used to determine gaze behaviour and motion capture analysis was used to determine toe kinematics relative to the obstacle. Combined, bilateral hip and knee proprioceptive sense (joint position sense and movement detection sense) was assessed using the Lokomat and customized software controls. Combined, bilateral hip and knee proprioceptive sense in subjects with SCI varied and was significantly different from able-bodied subjects. Subjects with greater proprioceptive deficits stepped higher over the obstacle with their lead and trail limbs in the obstructed vision condition compared with full vision. Subjects with SCI also glanced at the obstacle more frequently and with longer fixation times compared with controls, but this was not related to proprioceptive sense. This study indicates that ambulatory individuals with SCI rely more heavily on vision to cross obstacles and show impairments in key gait parameters required for successful obstacle crossing. Our data suggest that proprioceptive deficits need to be considered in rehabilitation programs aimed at improving functional mobility in ambulatory individuals with SCI.
NEW & NOTEWORTHY: This work is unique since it examines the contribution of combined, bilateral hip and knee proprioceptive sense on the recovery of skilled walking function, in addition to characterizing gaze behavior during a skilled walking task in people with motor-incomplete spinal cord injury.
熟练行走，如跨越障碍物，是功能性活动能力的重要组成部分。视觉和本体感觉输入的感觉运动整合对于成功跨越障碍物很重要。本研究的目的是了解在控制脊髓损伤（SCI）门诊患者运动缺陷变化的情况下，本体感觉缺陷如何影响跨越障碍物的策略。15名SCI门诊患者和15名健全对照者被要求在全视野和视野受阻条件下跨过一个根据其运动能力调整的障碍物。使用眼动仪确定注视行为，并使用运动捕捉分析确定相对于障碍物的脚趾运动学。使用Lokomat和定制软件控件评估双侧髋部和膝部本体感觉（关节位置觉和运动检测觉）的综合情况。SCI患者双侧髋部和膝部本体感觉综合情况各不相同，且与健全受试者有显著差异。与全视野相比，在视野受阻条件下，本体感觉缺陷较大的受试者其领先和落后肢体跨过障碍物的高度更高。与对照组相比，SCI患者也更频繁地注视障碍物，且注视时间更长，但这与本体感觉无关。本研究表明，SCI门诊患者在跨越障碍物时更依赖视觉，并且在成功跨越障碍物所需的关键步态参数方面存在障碍。我们的数据表明，在旨在改善SCI门诊患者功能活动能力的康复计划中需要考虑本体感觉缺陷。
这项工作具有独特性，因为它除了描述运动不完全性脊髓损伤患者在熟练行走任务中的注视行为外，还研究了双侧髋部和膝部本体感觉综合情况对熟练行走功能恢复的贡献。
