On the use of bone and skin markers in kinematics research

In the study of human kinematics, the object is generally to assess the movement of bone segments rather than the combined movement of bone and soft tissue. Therefore, movement derived from bone-anchored measurement devices is usually measured in studies of cadaveric specimens and considered superior to skin-derived motion measurements in in vivo situations. However, this is not necessarily true in all circumstances, as there are many possible problems and sources of error also in invasive research. A review of the literature concerning invasive measurements and literature relating to similar measurements using non-invasive techniques shows that few methods for non-invasive kinematics research have been validated. The invasive techniques used are generally well documented, but there is, for these techniques, a mar ked tendency to avoid some anatomical regions and study conditions. The purpose of this article is to make a summary of those methods that have to date been used for invasive research and their non-invasive counterparts, and to discuss possibilities for future studies.