Contribution of disc degeneration to osteophyte formation in the cervical spine: a biomechanical investigation

Journal of Orthopaedic Research - Tập 19 - Trang 977-984 - 2001
Srirangam Kumaresan1, Narayan Yoganandan1, Frank A Pintar1, Dennis J Maiman1, Vijay K Goel2
1Department of Veterans Affairs, Medical College of Wisconsin,VA Medical Center Research 151, 5000 West National Avenue Medical Center, Milwaukee, WI 53295, USA
2Department of Biomedical Engineering and Orthopedics, Iowa Spine Research Center, University of Iowa, Iowa City, IA 53295, USA

Tóm tắt

AbstractCervical spine disorders such as spondylotic radiculopathy and myelopathy are often related to osteophyte formation. Bone remodeling experimental—analytical studies have correlated biomechanical responses such as stress and strain energy density to the formation of bony outgrowth. Using these responses of the spinal components, the present study was conducted to investigate the basis for the occurrence of disc‐related pathological conditions. An anatomically accurate and validated intact finite element model of the C4‐C5‐C6 cervical spine was used to simulate progressive disc degeneration at the C5‐C6 level. Slight degeneration included an alteration of material properties of the nucleus pulposus representing the dehydration process. Moderate degeneration included an alteration of fiber content and material properties of the anulus fibrosus representing the disintegrated nature of the anulus in addition to dehydrated nucleus. Severe degeneration included decrease in the intervertebral disc height with dehydrated nucleus and disintegrated anulus. The intact and three degenerated models were exercised under compression, and the overall force—displacement response, local segmental stiffness, anulus fiber strain, disc bulge, anulus stress, load shared by the disc and facet joints, pressure in the disc, facet and uncovertebral joints, and strain energy density and stress in the vertebral cortex were determined. The overall stiffness (C4‐C6) increased with the severity of degeneration. The segmental stiffness at the degenerated level (C5‐C6) increased with the severity of degeneration. Intervertebral disc bulge and anulus stress and strain decreased at the degenerated level. The strain energy density and stress in vertebral cortex increased adjacent to the degenerated disc. Specifically, the anterior region of the cortex responded with a higher increase in these responses. The increased strain energy density and stress in the vertebral cortex over time may induce the remodeling process according to Wolff's law, leading to the formation of osteophytes. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.

Tài liệu tham khảo

10.1016/0021-9290(90)90354-6 10.1097/00007632-199506000-00022 10.1002/jor.1100130408 Cowin SC, 1989, Bone mechanics 10.1097/00007632-199808150-00005 Friedenberg Z, 1963, Degenerative disc disease of the cervical spine, J Bone Jt Surg, 45, 1171, 10.2106/00004623-196345060-00004 Garfin S, 1986, Structural behavior of the halo orthosis pin–bone interface: biomechanical evaluation of standard and newly designed stainless steel halo fixation pins, Spine, 11, 977, 10.1097/00007632-198612000-00001 Ghosh P, 1988, Biology of the intervertebral disc 10.1115/1.2794180 10.1097/00007632-199803150-00008 Hattori S, 1981, Cervical intradiscal pressure in movements and traction of the cervical spine, Z Orthop, 119, 568 Huiskes R, 1987, Toward an identification of mechanical parameters initiating periosteal remodeling: a combined experimental and analytic approach, J Biomech, 20, 1135 10.1097/00007632-198909000-00016 10.1097/00007632-199103000-00013 Kumaresan S, 1997, Finite element modeling of cervical laminectomy with graded facetectomy, J Spinal Disord, 10, 40, 10.1097/00002517-199702000-00006 Kumaresan S, 1999, Finite element analysis of the cervical spine: a material property sensitivity study, Clin Biomech, 14, 41, 10.1016/S0268-0033(98)00036-9 KumaresanS YoganandanN PintarFA MaimanDJ. Finite element modeling of the lower cervical spine: Role of intervertebral disc under axial and eccentric loads.Med Eng Phys in press. Kurowski P, 1986, The relationship of degeneration of the intervertebral disc to mechanical loading conditions on lumbar vertebrae, Spine, 11, 726, 10.1097/00007632-198609000-00012 Lestini W, 1989, The pathogenesis of cervical spondylosis, Clin Orthop Rel Res, 239, 69, 10.1097/00003086-198902000-00009 MoroneyS.Mechanical properties and muscle force analyses of the lower cervical spine. Doctoral Dissertation. Chicago: University of Illinois;1984. 10.1097/00007632-199402000-00001 Nathan H, 1962, Osteophytes of the vertebral column, J Bone Jt Surg, 44, 243, 10.2106/00004623-196244020-00003 Patwardhan A, 1999, A follower load increases the load‐carrying capacity of the lumbar spine in compression, Spine, 4, 1003, 10.1097/00007632-199905150-00014 10.1115/1.2794210 10.1007/BF02427846 10.1016/0021-9290(91)90354-P Shirazi‐Adl SA, 1992, Finite element simulation of changes in the fluid content of human lumbar discs: mechanical and clinical implications, Spine, 17, 206, 10.1097/00007632-199202000-00015 10.1002/bjs.1800228818 Yoganandan N, 1997, Finite element model of the human lower cervical spine, J Biomech Eng, 119, 87, 10.1115/1.2796070 Yoganandan N, 2000, Frontiers in Whiplash Trauma: clinical and biomechanical, 590 Yoganandan N, 1998, Frontiers in head and neck trauma: clinical and biomechanical, 743
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Journal of Orthopaedic Research

Tập 19

977-984

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