“…The outputs obtained from a group of gauges measured extra-articular surface strain during loading. This method has been used successfully in studies involving both canine (Buttermann et al, 1991;Kahmann et al, 1990) and human (Schendel et al, 1993) spine segments, and has been validated theoretically (Luo et al, 1996). Although fairly accurate, the method is tedious and limited to cases in which the facet bone is plate-like (Luo et al, 1996).…”