Effect of technique and transfer board use on the performance of wheelchair transfers.

Transferring to and from the wheelchair seat is a necessary skill for many wheelchair users who wish to be independent of their everyday life. The performance of wheelchair transfers has been associated with the risk of falling and developing upper limb injuries. Both present a risk to the independence of the individual. Previous studies on wheelchair transfers have focused mainly on the analysis of sitting transfers performed by individuals with spinal cord injury, which only represent a small portion of the wider wheelchair users' population. The purpose of this study is to investigate the effect of different transferring techniques (sitting, standing) and transfer board use on the ground reaction forces under the hands during transfer performance and transfer quality measured using the transfer assessment instrument (TAI). Sitting transfers displayed generally higher peak and mean reaction forces underneath both leading and trailing hands compared with the other techniques, but the difference was only significant between sitting and standing transfers. Standing transfers had significantly lower TAI scores compared with sitting transfer, potentially indicating a decreased level of safety associated with their performance. Transfer boards were only partially effective in reducing the weight born by the upper limbs and they caused only a minor reduction in the overall TAI score in comparison to sitting transfers.

Characterisation of rollator use using inertial sensors.

The use of walking aids is prevalent among older people and people with mobility impairment. Rollators are designed to support outdoor mobility and require the user to negotiate curbs and slopes in the urban environment. Despite the prevalence of rollators, analysis of their use outside of controlled environments has received relatively little attention. This Letter reports on an initial study to characterise rollator movement. An inertial measurement unit (IMU) was used to measure the motion of the rollator and analytical approaches were developed to extract features characterising the rollator movement, properties of the surface and push events. The analytics were tested in two situations: first, a healthy participant used a rollator in a laboratory using a motion capture system to obtain ground truth. Second, the IMU was used to measure the movement of a rollator being used by a user with multiple sclerosis on a flat surface, cross-slope, up and down slopes and up and down a step. The results showed that surface inclination and distance travelled measured by the IMU have close approximation to the results from ground truth; therefore, demonstrating the potential for IMU-derived metrics to characterise rollator movement and user's pushing style in the outdoor environment.