Comparison of surface mounted markers and attachment methods in estimatingtibial rotations during walking: an in vivo study

The overall goal of this work was to determine an optimal surface-tracking marker set Ibr tracking motion of the tibia during natural cadence walking. Eleven different marker sets were valuated. The marker sets differed in lo cation they were attached to the shank. the method used to attach the marke r sets to the segment and the physical characteristics of the marker sets. Angular position during stance for each marker set was expressed relative t o the orientation of the tibia as measured using bone anchored markers. A m arker set consisting of four markers attached to a rigid shell positioned o ver the distal lateral shank and attached to the leg using an underwrap att achment yielded the brst estimate of tibial rotation. Rotational deviations of +/- 2 degrees about the medio-lateral and antero-posterior axes. and +/ - 4 degrees about the longitudinal axis did occur even when using the optim al set of markers. (C) 2000 Elsevier Science B.V. All rights reserved.