Gyroscopes have been proposed as sensors for ambulatory gait analysis and functional electrical stimulation systems. Accurate determination of the Initial Contact of the foot with the floor (IC) and the final contact or Foot Off (FO) on different terrains is important. This paper describes the evaluation of a gyroscope placed on the shank for determination of IC and FO in subjects walking outdoors on level ground, and up and down an incline. Performance was compared with a reference pressure measurement system. The mean difference between the gyroscope and the reference was less than −25 ms for IC and less than 75 ms for FO for all terrains. Detection success was over 98%. These results provide preliminary evidence supporting the use of the gyroscope for gait event detection on inclines as well as level walking.

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Crouch gait is the most common motion abnormality in children with cerebral palsy (CP). This paper presents a new biomechanical model based on a simple rescaling and adjustment to CP patients who develop crouch gait by subject-specific anthropometric data. The model estimates the length of hamstrings, as the distance between the origin and insertion of the muscle, and the velocity of shortening of hamstrings by the first derivative of the length with respect to time. This model has the potential to increase the benefits of three-dimensional biomechanical models as it can discriminate between short, spastic or normal hamstrings. The main advantage of this model in clinical use is that it does not require costly magnetic resonance imaging.

Purpose: A variety of methods have been proposed for detection of initial contact (IC) and foot off (FO) and some comparative analysis is reported in the literature. Pressure measurement insoles and kinematic systems are often part of footwear analysis. Although gait event detection algorithms using these systems have been proposed and evaluated against kinetic data (KN) from force platforms (typically used as a 'gold standard'), they have not been compared directly. The objective of this work was to undertake this comparison using the same volunteer dataset and test conditions.Methods: Data from 10 healthy adults walking at self-selected normal speed were collected. Two kinematic algorithms (one using a fixed threshold, KM, and the other using high pass-filtering, HPA) and one algorithm using pressure measurement data from an insole (Contact Area Detection, AD) were tested and compared with the detection provided by KN. All data were synchronised and sampled at 200 Hz. Six basic spatio-temporal parameters were also calculated.Results: The absolute mean difference (AMD) in event detection between the three methods and KN was below 25 ms. However, the methods presented tendencies to detect events earlier or later than KN and this influenced the AMD between the methods, which increased to 47 ms for IC detection between HPA and AD. The spatio-temporal parameters showed no statistically significant differences between AD and KM, but differences reached statistical significance between AD and HPA.Conclusion: It is possible to compare gait events and basic spatio-temporal parameters detected using data from pressure measurement insoles and kinematic algorithms; however the kinematic algorithm used will influence the results. Hence the comparison of findings from alternative detection methods is an important issue for which information about the behaviour of the method used is required. © 2014 © 2014 Taylor & Francis