Repeatability of an optimised lower body model.

I W Charlton; P Tate; P Smyth; L Roren

doi:10.1016/j.gaitpost.2003.09.004

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Repeatability of an optimised lower body model.

I W Charlton·P Tate·P Smyth·L Roren

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Abstract

The optimisation technique, optimised lower-limb gait analysis (OLGA), is described together with a preliminary study of repeatability compared to an implementation of the Newington-Helen Hayes gait model. The study of repeatability used a single healthy subject, three physiotherapists as observers and provided approximately 100 gait cycles. Improvement in intra- and inter-observer repeatability of the lower limb model was found for OLGA, indicated by significantly lower standard deviations (S.D.s) in local marker co-ordinate (a measure of rigidity of the marker attachment), together with reduced S.D. in the estimated length of the bone segments. The S.D. in the inter-hip distance measured by OLGA (N = 25) was found to be only 2.4 mm. The repeatability of clinically significant output variables (joint angles, forces and moments) was also improved, with the inter-observer variations for joint angles and forces being significantly lower for OLGA. Euler angle component cross-talk effects frequently reported at the hip, knee and ankle were also successfully reduced by OLGA, this being the chief cause of the improvement in inter-observer repeatability.

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Algorithms Ankle Joint Gait Hip Humans Knee Joint Models, Theoretical Observer Variation Reproducibility of Results Journal Article

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I W Charlton, P Tate, P Smyth, L Roren. 2004. Repeatability of an optimised lower body model.. https://doi.org/10.1016/j.gaitpost.2003.09.004

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