Lower extremity coordination during walking in persons who are blind and sighted controls: A preliminary report

Walking is the most common mode of physical activity for individuals who are blind. However, this population tends to be physically inactive, possibly due to alterations in coordination patterns during walking. Therefore, the purpose of this study was to examine lower extremity coordination patterns during walking in persons who are blind, and age-, sex-, and body mass index-matched sighted controls. Five persons who are blind performed level walking independently (with a cane) and with a human guide. Sighted controls walked at matched speeds for both conditions. A 10-camera motion capture system was used to record segmental kinematics during both walking conditions. Angle-angle plots and modified vector coding was used to present inter-limb (left/right thigh) and intra-limb (ankle-hip, ankle-knee, and knee-hip) couplings across both walking conditions for each group. Frequency of coupling patterns was compared between groups using Mann-Whitney's U tests. Inter- and intra-limb coordination patterns were similar between both groups during independent and guided walking conditions (all p > .05). Angle-angle plots depict reduced segmental and joint motion in persons who are blind compared with sighted controls. Although the visual feedback system is integral for coordination during complex tasks, persons who are blind perform level walking with similar lower extremity coordination patterns to sighted controls. Reductions in spatiotemporal and range of motion are likely linked to a more hesitant stepping pattern due to unfamiliarity with the environment.