A common approach to measuring anatomical joint motion consists of tracking the XYZ locations of point targets which are attached to the moving anatomical limb segments. Unfortunately, there are several artifacts associated with the measurement which add errors to the resulting computed 6 degrees of freedom of joint motion. This paper addresses the various artifacts which affect the measurement of the relative joint motion between the adjacent segments. Many of these artifacts were modeled in a computer simulation to quantitatively study their effects on determining this joint motion. Based on these simulations, several relationships were identified which predict how each of these artifacts influence the predicted measurement of relative motion between bodies. These suggest where emphasis should be placed in order to minimize the error in measuring the 6 degrees of freedom associated with joint motion. Lastly, a design curve is presented which can be used to map these results into motion measurement systems with different XYZ coordinate measurement errors.
|Original language||English (US)|
|Number of pages||4|
|Journal||American Society of Mechanical Engineers, Bioengineering Division (Publication) BED|
|State||Published - Dec 1 1988|