Hi Mr. Elnawasry

 I send to you some papers that deal about this subject.

I hope this helps.

http://www.chiro.org/ACAPress/Body_Alignment.html

http://www.tandfonline.com/doi/abs/10.1080/14640749508401412#.VqJYoVKviYQ

thanks Marcelo Guimarães Silva

Dear my  colleague Hamdy,

I hope the following papers help you.

Buller, P. F., & McEvoy, G. M. (2012). Strategy, human resource management and performance: Sharpening line of sight. Human Resource Management Review. http://doi.org/10.1016/j.hrmr.2011.11.002

Cholewicki, J., & McGill, S. M. (1996). Mechanical stability of the in vivo lumbar spine: Implications for injury and chronic low back pain. Clinical Biomechanics, 11(1), 1–15. http://doi.org/10.1016/0268-0033(95)00035-6

Colloca, C. J., Keller, T. S., Harrison, D. E., Moore, R. J., Gunzburg, R., & Harrison, D. D. (2006). Spinal manipulation force and duration affect vertebral movement and neuromuscular responses. Clinical Biomechanics, 21(3), 254–262. http://doi.org/10.1016/j.clinbiomech.2005.10.006

Danion, F., & Sarlegna, F. R. (2007). Can the human brain predict the consequences of arm movement corrections when transporting an object? Hints from grip force adjustments. The Journal of Neuroscience : The Official Journal of the Society for Neuroscience, 27(47), 12839–12843. http://doi.org/10.1523/JNEUROSCI.3110-07.2007

Dulhunty, J. (2002). A simplified conceptual model of the human cervical spine for evaluating force transmission in upright static posture. Journal of Manipulative and Physiological Therapeutics, 25(5), 306–317. http://doi.org/10.1067/mmt.2002.124421

Flanagan, J. R., & Wing, a M. (1997). The role of internal models in motion planning and control: evidence from grip force adjustments during movements of hand-held loads. The Journal of Neuroscience : The Official Journal of the Society for Neuroscience, 17(4),

Han, J. S., Goel, V. K., & Kumar, S. (1991). A nonlinear optimization force model of the human lumbar spine. International Journal of Industrial Ergonomics, 8(3), 289–301. http://doi.org/10.1016/0169-8141(91)90039-O

Hansen, L., de Zee, M., Rasmussen, J., Andersen, T. B., Wong, C., & Simonsen, E. B. (2006). Anatomy and biomechanics of the back muscles in the lumbar spine with reference to biomechanical modeling. Spine, 31(17), 1888–99.

Keenan, K. G., Santos, V. J., Venkadesan, M., & Valero-Cuevas, F. J. (2009). Maximal voluntary fingertip force production is not limited by movement speed in combined motion and force tasks. The Journal of Neuroscience : The Official Journal of the Society for Neuroscience, 29(27), 8784–8789. http://doi.org/10.1523/JNEUROSCI.0853-09.2009

Lackner, J. R., & Dizio, P. (1994). Rapid adaptation to Coriolis force perturbations of arm trajectory. J Neurophysiol, 72(1), 299–313. http://doi.org/citeulike-article-id:450102

Ledet, E. H., Tymeson, M. P., DiRisio, D. J., Cohen, B., & Uhl, R. L. (2005). Direct real-time measurement of in vivo forces in the lumbar spine. Spine Journal, 5(1), 85–94. http://doi.org/10.1016/j.spinee.2004.06.017

Luinge, H. J., & Veltink, P. H. (2004). Inclination measurement of human movement using a 3-D accelerometer with autocalibration. IEEE Transactions on Neural Systems and Rehabilitation Engineering : A Publication of the IEEE Engineering in Medicine and Biology Society, 12(1), 112–121. http://doi.org/10.1109/TNSRE.2003.822759

Shirazi-Adl, A., & Parnianpour, M. (1993). Nonlinear response analysis of the human ligamentous lumbar spine in compression. On mechanisms affecting the postural stability. Spine, 18(1), 147–58. http://doi.org/10.1097/00007632-199301000-00021

Shirazi-Adl, A., Sadouk, S., Parnianpour, M., Pop, D., & El-Rich, M. (2002). Muscle force evaluation and the role of posture in human lumbar spine under compression. European Spine Journal, 11(6), 519–526. http://doi.org/10.1007/s00586-002-0397-7

Shum, G. L. K., Crosbie, J., & Lee, R. Y. W. (2005). Symptomatic and asymptomatic movement coordination of the lumbar spine and hip during an everyday activity. Spine, 30(23), E697–702. http://doi.org/10.1097/01.brs.0000188255.10759.7a

Teo, E. C., & Ng, H. W. (2001). Evaluation of the role of ligaments, facets and disc nucleus in lower cervical spine under compression and sagittal moments using finite element method. Medical Engineering and Physics, 23(3), 155–164. http://doi.org/10.1016/S1350-4533(01)00036-4

Vaz, G., Roussouly, P., Berthonnaud, E., & Dimnet, J. (2002). Sagittal morphology and equilibrium of pelvis and spine. European Spine Journal, 11(1), 80–87. http://doi.org/10.1007/s005860000224

Wada, O., Tateuchi, H., & Ichihashi, N. (2014). The correlation between movement of the center of mass and the kinematics of the spine, pelvis, and hip joints during body rotation. Gait and Posture, 39(1), 60–64. http://doi.org/10.1016/j.gaitpost.2013.05.030

Wu, B., Wang, C., Krug, R., Kelley, D. A., Xu, D., Pang, Y., … Zhang, X. (2010). 7T human spine imaging arrays with adjustable inductive decoupling. IEEE Transactions on Bio-Medical Engineering, 57(2), 397–403. http://doi.org/10.1109/TBME.2009.2030170

Regards, 

Abdel-Rahman

thank you very mush dr Abdel-Rahman Akl