Decreasing an Offloading Device's Size and Offsetting Its Imposed Limb-Length Discrepancy Lead to Improved Comfort and Gait.

Abstract

Patient adherence is a challenge in offloading diabetic foot ulcers (DFUs) with removable cast walkers (RCWs). The size and weight of an RCW, changes to gait, and imposed limb-length discrepancies may all discourage adherence. This study sought to determine whether RCW size and provision of a contralateral limb lift affected users' comfort and gait. Twenty-five individuals at risk for DFUs completed several 20-m walking trials under five footwear conditions: bilateral standardized shoes, a knee-high RCW with shoe with or without an external shoe lift contralaterally, and an ankle-high RCW with shoe with or without an external shoe lift contralaterally. Perceived comfort ratings were assessed through the use of visual analog scales. Spatial and temporal parameters of gait were captured by an instrumented walkway, and plantar pressure was measured and recorded using pedobarographic insoles. The bilateral shoes condition was reported to be most comfortable; both RCW conditions without the lift were significantly less comfortable (<i>P</i> < 0.01). In contrast to the ankle-high RCW, the knee-high RCW resulted in significantly slower walking (5.6%; <i>P</i> < 0.01) but greater offloading in multiple forefoot regions of the offloaded foot (6.8-8.1%; <i>P</i> < 0.01). Use of the contralateral shoe lift resulted in significantly less variability in walking velocity (52.8%; <i>P</i> < 0.01) and reduced stance time for the offloaded foot (2.6%; <i>P</i> = 0.01), but it also reduced offloading in multiple forefoot regions of the offloaded foot (3.7-6.0%; <i>P</i> < 0.01). Improved comfort and gait were associated with the ankle-high RCW and contralateral limb lift. Providing this combination to patients with active DFUs may increase offloading adherence and subsequently improve healing.