As an important support and load structure of human body, spine has become animportant research content of clinicians and researchers. A precisely, quantitativelydescription of the dimensional stability of the spinal motion has an extremely importantsignificance for understanding the mechanism of the occurrence of the spinal injury anddiseases thereby determining a reasonable treatment method. It is also important for thecorrect assessment of the impact of the surgery and implants for spinal movementbehavio...