Assessment of spatio-temporal gait parameters using inertial measurement units in neurological populations.

Laboratory based gait analysis techniques are expensive, time consuming and require technical expertise. Inertial measurement units can directly measure temporal parameters and in combination with gait models may provide a solution to obtain spatial gait measurements within daily clinical assessments. However it is not known if a model and standard correction factor determined by Zijlstra and Hof [8] to estimate step and stride length parameters in typically developed adults (TDA) can be accurately used in neurologically impaired gaits. This research estimated the stride length over two 10 m walks at self selected walking speed in people with neurological conditions, using a previously established model and correction factor for TDA. The relation of the correction factor to walking speed was explored. We recruited TDA (n=10) and participants with Parkinson's disease (PD; n=24), muscular dystrophy (MD; n=13), motor neuron disease (MND; n=7) and stroke survivors (n=18) for the study who twice walked 10 m at a self-selected pace. Stride length correction factors, for TDA (1.25±0.01), PD (1.25±0.03), and MD (1.21±0.08) (p=0.833 and p=0.242) were the same as previously reported in TDA (Zijlstra and Hof [8]). Correction factors for stroke (1.17±0.42) and MND (1.10±0.08) were different (p<0.01 and p=0.028 respectively). However there was a high level of variability for correction factors within groups, which did not relate to walking speed. Our findings support that correction factors should be determined for each individual to estimate average step/stride length in patients suffering from a neurological condition.