O. Shirado, T. Ito, K. Kaneda and T. E. Stra, “Flexion-Relaxation Phenomenon in the Back Muscles: a Comparative-Study between Healthy Subjects and Patients with Chronic Low Back Pain,” American Journal of Physical Medicine & Rehabilitation, Vol. 74, No. 2, 1995, pp. 139-144.
 M. M. Panjabi and A. A. White, “Kinematics of the Spine,” In: M. M. Panjabi and A. A. White, Eds., Clinical Biomechanics of the Spine, 2nd Edition, J. B. Lippincott Co., Philadelphia, 1990, pp. 85-126.
 J. W. Frymoyer and D. K. Selby, “Segmental Instability: Rationale for Treatment,” In: G. R. Bell, S. W. Wiesel, J. N. Weinstein, H. N. Herkowitz and J. Dvorak, Eds., The Lumbar Spine, 2nd Edition, W. B. Saunders Co., Philadelphia, 1996, pp. 43-52.
 J. M. Olsewski, E. H. Simmons, F. C. Kallen, F. C. Mendel, C. M. Severin and D. L. Berens, “Morphometry of the Lumbar Spine: Anatomical Perspectives Related to Transpedicular Fixation,” Journal of Bone and Joint Surgery American, Vol. 72, No. 4, 1990, pp. 541-549.
 M. M. Panjabi, V. Goel, T. Oxland, K. Takata, J. Duran- ceau, M. Krag, et al., “Human Lumbar Vertebrae: Quantitative Three-Dimensional Anatomy,” Spine (Phila Pa 1976), Vol. 17, No. 3, 1992, pp. 299-306.
 M. M. Panjabi, K. Takata, V. Goel, D. Federico, T. Oxland, J. Duranceau, et al., “Thoracic Human Vertebrae. Quantitative Three-Dimensional Anatomy,” Spine (Phila Pa 1976), Vol. 16, No. 8, 1991, pp. 888-901.
 S. W. Lee, K. W. Wong, M. K. Chan, H. M. Yeung, J. L. Chiu and J. C. Leong, “Development and Validation of a New Technique for Assessing Lumbar Spine Motion,” Spine (Phila Pa 1976), Vol. 27, No. 8, 2002, pp. E215- E20.
 D. S. Teyhen, T. W. Flynn, A. C. Bovik and L. D. Abraham, “A New Technique for Digital Fluoroscopic Video Assessment of Sagittal Plane Lumbar Spine Motion,” Spine (Phila Pa 1976), Vol. 30, No. 14, 2005, pp. E406- E413.
 A. Breen, R. Allen and A. Morris, “A Digital Video Flu- oroscopic Technique for Spine Kinematics,” Journal of Medical Engineering & Technology, Vol. 13, No. 1-2, 1989, pp. E109-E113. http://dx.doi.org/10.3109/03091908909030208
 D. Vander Kooi, G. Abad, J. R. Basford, T. P. Maus, M. J. Yaszemski and K. R Kaufman, “Lumbar Spine Stabilization with a Thoraco-lumbosacral Orthosis: Evaluation with Video Fluoroscopy,” Spine (Phila Pa 1976), Vol. 29, No. 1, 2004, pp. 100-104.
 A. C. Breen, R. Allen and A. Morris, “Spine Kkinematics: a Digital Videofluoroscopic Technique,” Journal of biomedical engineering, Vol. 11, No. 3, 1989, pp. 224-228. http://dx.doi.org/10.1016/0141-5425(89)90146-5
 K. Ta-kayanagi, K. Takahashi, M. Yamagata, H. Moriya, H. Kitahara and T. Tamaki, “Using Cineradiography for Continuous Dynamic-motion Analysis of the Lumbar Spine,” Spine, Vol. 26, No. 17, 2001, pp. 1858-1865.
 P. Bifulco, M. Cesarelli, R. Allen and M. Bracale, “Automatic Extraction of Kinematic Parameters from Videofluoroscopic Sequences of the Spine,” Proceedings of Health Telematics, Naples, 1995, pp. 147-148.
 A. Thorkeldsen and A. C. Breen, “Gray Scale Range and the Marking of Vertebral Coordinates on Digitized Radiographic Images,” Journal of manipulative and physiological therapeutics, Vol. 17, No. 6, 1994, pp. 359-363.
 A. Okawa, K. Shinomiya, H. Komori, T. Muneta, Y. Arai, and O. Nakai, “Dynamic Motion Study of the Whole Lumbar Spine by Videofluoroscopy,” Spine (Phila Pa 1976), Vol. 23, No. 16, 1998, pp. 1743-1749.