Handle-height adjustment effects on gait kinetics in older adults while walking with a rollator
An increasing geriatric population has increased the demand for walking-aids among this population. The use of walking-aids requires proper adjustment to maintain adequate shared weight-bearing while maintaining correct posture. Current guidelines leave users with vague instructions not allowing for proper adjustment of these devices. The purpose of this investigation was to determine the effects of handle-height adjustment on gait kinematics and kinetics in able-bodied older adults when walking with an all-terrain rollator. Participants were tested while walking at 80 and 100% of their normal cadence. Thirty-three participants were recruited from the Denton, TX, area. Every participant signed an IRB approved Informed Consent Form. Participants were asked to complete 5 successful trials for each of the different handle adjustments (i.e., 48% of the user’s height, 55% of the user’s height, and wrist crease height) on two cadences (i.e., normal cadence and slow cadence); the participant was also asked to walk without the rollator as a control condition for each walking cadence condition. Participants were instructed to walk as naturally as possible while applying force over the rollator. Kinetic variables measured include ground reaction force, lower body resultant joint moment, postural back angles and walking velocity were extracted in order to see the effects of the rollator. Significant decrease in vertical, forward, backward, and inward GRF from 11.9-26.5% was seen, and, hip flexor, hip abductor from, and ankle plantar flexor and invertor moments up to 16% reduction, while an increased L4/L5 flexor moment by 25% were found while using the rollator. These effects were accompanied by a reduction of kyphosis from 1.3 to 1.4% and lordosis up to 1%, but with an increase in thorax flexion by 8-11% and shoulder elevation by 7-10%. The use of a rollator reduced the forces received by the lower limb joints, but a more stooped posture was acquired, increasing the stress over the L4/L5 joint. Rollator adjustment depends on the clinical goals set for the use of the device as well as the user’s need for mobility.