• ,四川大學(xué)華西醫(yī)院骨科（成都， 610041）;

【摘 要】 目的  總結(jié)頸椎后路椎管擴大成形術(shù)后并發(fā)癥中發(fā)病機制尚未完全了解的軸性癥狀、后凸畸形、節(jié)段性運動麻痹的研究進展。 方法  查閱有關(guān)頸椎后路椎管擴大成形術(shù)后并發(fā)癥文獻，并綜合分析。 結(jié)果  軸性癥狀、后凸畸形、節(jié)段性運動麻痹并發(fā)癥的發(fā)病機制尚未完全了解，但已有了更多新的發(fā)現(xiàn)，如椎體后方肌肉韌帶復(fù)合體的重要性和引起節(jié)段性運動麻痹的神經(jīng)根麻痹、脊髓損傷兩種學(xué)說。 結(jié)論  應(yīng)對軸性癥狀、后凸畸形、節(jié)段性運動麻痹并發(fā)癥的發(fā)病機制作進一步研究，以期能有效防治其發(fā)生。

引用本文： 幸?guī)V,孔清泉. 頸椎后路椎管擴大成形術(shù)后并發(fā)癥的研究進展. 中國修復(fù)重建外科雜志, 2012, 26(3): 284-288. doi: 復(fù)制

1. Kaplan L, Bronstein Y, Barzilay Y, et al. Canal expansive laminoplasty in the management of cervical spondylotic myelopathy. Isr Med Assoc J, 2006, 8(8): 548-552.
2. Edwards CC 2nd, Heller JG, Murakami H. Corpectomy versus laminoplasty for multilevel cervical myelopathy: an independent matched-cohort analysis. Spine (Phila Pa 1976), 2002, 27(11): 1168-1175.
3. Herkowitz HN. A comparison of anterior cervical fusion, cervical laminectomy, and cervical laminoplasty for the surgical management of multiple level spondylotic radiculopathy. Spine (Phila Pa 1976), 1988, 13(7): 774-780.
4. Klineberg E. Cervical spondylotic myelopathy: a review of the evidence. Orthop Clin North Am, 2010, 41(2): 193-202.
5. Kawaguchi Y, Matsui H, Ishihara H, et al. Axial symptoms after en bloc cervical laminoplasty. J Spinal Disord, 1999, 12(5): 392-395.
6. Ratliff JK, Cooper PR. Cervical laminoplasty: a critical review. J Neurosurg, 2003, 98(3 Suppl): 230-238.
7. Kotani Y, Abumi K, Ito M, et al. Minimum 2-year outcome of cervical laminoplasty with deep extensor muscle-preserving approach: impact on cervical spine function and quality of life. Eur Spine J, 2009, 18(5): 663-671.
8. Takeuchi K, Yokoyama T, Aburakawa S, et al. Axial symptoms after cervical laminoplasty with C3 laminectomy compared with conventional C3-C7 laminoplasty: a modified laminoplasty preserving the semispinalis cervicis inserted into axis. Spine (Phila Pa 1976), 2005, 30(22): 2544-2549.
9. Shiraishi T, Fukuda K, Yato Y, et al. Results of skip laminectomy-minimum 2-year follow-up study compared with open-door laminoplasty. Spine (Phila Pa 1976), 2003, 28(24): 2667-2672.
10. Nolan JP Jr, Sherk HH. Biomechanical evaluation of the extensor musculature of the cervical spine, Spine (Phila Pa 1976), 1988, 13(1): 9-11.
11. Han DW, Koo BN, Chung WY, et al. Preoperative greater occipital nerve block in total thyroidectomy patients can reduce postoperative occipital headache and posterior neck pain. Thyroid, 2006, 16(6): 599-603.
12. Sakaura H, Hosono N, Mukai Y, et al. Preservation of muscles attached to the C2 and C7 spinous processes rather than subaxial deep extensors reduces adverse effects after cervical laminoplasty. Spine (Phila Pa 1976), 2010, 35(16): E782-786.
13. Takeuchi K, Yokoyama T, Aburakawa S, et al. Postoperative changes at the lower end of cervical laminoplasty: for preservation of the C7 spinous process in laminoplasty. J Spinal Disord Tech, 2006, 19(6): 402-406.
14. Takeshita K, Seichi A, Akune T, et al. Can laminoplasty maintain the cervical alignment even when the C2 lamina is contained? Spine (Phila Pa 1976), 2005, 30(11): 1294-1298.
15. IizukaH, Shimizu T, Tateno K, et al. Extensor musculature of the cervical spine after laminoplasty: morphologic evaluation by coronal view of the magnetic resonance image. Spine (Phila Pa 1976), 26(20): 2220-2226.
16. Kato M, Nakamura H, Konishi S, et al. Effect of preserving paraspinal muscles on postoperative axial pain in the selective cervical laminoplasty. Spine (Phila Pa 1976), 2008, 33(14): E455-459.
17. Sakaura H, Hosono N, Mukai Y, et al. Preservation of muscles attached to the C2 and C7 spinous processes rather than subaxial deep extensors reduces adverse effects after cervical laminoplasty. Spine (Phila Pa 1976), 2010, 35(16): E782-786.
18. Fujibayashi S, Neo M, Yoshida M, et al. Neck muscle strength before and after cervical laminoplasty: relation to axial symptoms. J Spinal Disord Tech, 2010, 23(3): 197-202.
19. Hosono N, Sakaura H, Mukai Y, et al. C3-6 laminoplasty takes over C3-7 laminoplasty with significantly lower incidence of axial neck pain. Eur Spine J, 2006, 15(9): 1375-1379.
20. Ono A, Tonosaki Y, Yokoyama T, et al. Surgical anatomy of the nuchal muscles in the posterior cervicothoracic junction: significance of the preservation of the C7 spinous process in cervical laminoplasty. Spine (Phila Pa 1976), 2008, 33(11): E349-354.
21. Yasuoka S, Peterson HA, MacCarty CS. Incidence of spinal column deformity after multilevel laminectomy in children and adults. J Neurosurg, 1982, 57(4): 441-445.
22. Okada M, Minamide A, Endo T, et al. A prospective randomized study of clinical outcomes in patients with cervical compressive myelopathy treated with open-door or French-door laminoplasty. Spine (Phila Pa 1976), 2009, 34(11): 1119-1126.
23. Kowatari K, Ueyama K, Sannohe A, et al. Preserving the C7 spinous process with its muscles attached: effect on axial symptoms after cervical laminoplasty. J Orthop Sci, 2009, 14(3): 279-284.
24. Takeuchi K, Yokoyama T, Aburakawa S, et al. Anatomic study of the semispinalis cervicis for reattachment during laminoplasty. Clin Orthop Relat Res, 2005, (436): 126-131.
25. Liu J, Ebraheim NA, Sanford CG Jr, et al. Preservation of the spinous process-ligament-muscle complex to prevent kyphotic deformity following laminoplasty. Spine J, 2007, 7(2): 159-164.
26. Matsumoto M, Nojiri K, Chiba K, et al. Open-door laminoplasty for cervical myelopathy resulting from adjacent-segment disease in patients with previous anterior cervical decompression and fusion. Spine (Phila Pa 1976), 2006, 31(12): 1332-1337.
27. Albert TJ, Vacarro A. Postlaminectomy kyphosis. Spine (Phila Pa 1976), 1998, 23(24): 2738-2745.
28. Sciubba DM, Chaichana KL, Woodworth GF, et al. Factors associated with cervical instability requiring fusion after cervical laminectomy for intradural tumor resection. J Neurosurg Spine, 2008, 8(5): 413-419.
29. Katsumi Y, Honma T, Nakamura T. Analysis of cervical instability resulting from laminectomies for removal of spinal cord tumor. Spine (Phila Pa 1976), 1989, 14(11): 1171-1176.
30. Inoue A, Ikata T, Katoh S. Spinal deformity following surgery for spinal cord tumors and tumorous lesions: analysis based on an assessment of the spinal functional curve. Spinal Cord, 1996, 34(9): 536-542.
31. Steinbok P, Boyd M, Cochrane D. Cervical spinal deformity following craniotomy and upper cervical laminectomy for posterior fossa tumors in children. Childs Nerv Syst, 1989, 5(1): 25-28.
32. Zhang J, Hirabayashi S, Saiki K, et al. Effectiveness of multiple-level decompression in laminoplasty and simultaneous C1 laminectomy for patients with cervical myelopathy. Eur Spine J, 2006, 15(9): 1367-1374.
33. Takeshita K, Seichi A, Akune T, et al. Can laminoplasty maintain the cervical alignment even when the C2 lamina is contained? Spine (Phila Pa 1976), 2005, 30(11): 1294-1298.
34. Imagama S, Matsuyama Y, Yukawa Y, et al. C5 palsy after cervical laminoplasty: a multicentre study. J Bone Joint Surg (Br), 2010, 92(3): 393-400.
35. Roselli R, Pompucci A, Formica F, et al. Open-door laminoplasty for cervical stenotic myelopathy: surgical technique and neurophysiological monitoring. J Neurosurg, 2000, 92(1 Suppl): 38-43.
36. Yue WM, Tan CT, Tan SB, et al. Results of cervical laminoplasty and a comparison between single and double trap-door techniques. J Spinal Disord, 2000, 13(4): 329-335.
37. Edwards CC 2nd, Heller JG, Silcox DH 3rd. T-Saw laminoplasty for the management of cervical spondylotic myelopathy: clinical and radiographic outcome. Spine (Phila Pa 1976), 2000, 25(14): 1788-1794.
38. Satomi K, Ogawa J, Ishii Y, et al. Short-term complications and long-term results of expansive open-door laminoplasty for cervical stenotic myelopathy. Spine J, 2001, 1(1): 26-30.
39. Morio Y, Yamamoto K, Teshima R, et al. Clinicoradiologic study of cervical laminoplasty with posterolateral fusion or bone graft. Spine (Phila Pa 1976), 2000, 25(2): 190-196.
40. Satomi K, Nishu Y, Kohno T, et al. Long-term follow-up studies of open-door expansive laminoplasty for cervical stenotic myelopathy. Spine (Phila Pa 1976), 1994, 19(5): 507-510.
41. Jimenez JC, Sani S, Braverman B, et al. Palsies of the fifth cervical nerve root after cervical decompression: prevention using continuous intraoperative electromyography monitoring. J Neurosurg Spine, 2005, 3(2): 92-97.
42. Hirabayashi K, Toyama Y, Chiba K. Expansive laminoplasty for myelopathy in ossification of the longitudinal ligament. Clin Orthop Relat Res, 1999, (359): 35-48.
43. Uematsu Y, Tokuhashi Y, Matsuzaki H. Radiculopathy after laminoplasty of the cervical spine. Spine (Phila Pa 1976), 1998, 23(19): 2057-2062.
44. Minoda Y, Nakamura H, Konishi S, et al. Palsy of the C5 nerve root after midsagittal-splitting laminoplasty of the cervical spine. Spine (Phila Pa 1976), 2003, 28(11): 1123-1127.
45. Wada E, Suzuki S, Kanazawa A, et al. Subtotal corpectomy versus laminoplasty for multilevel cervical spondylotic myelopathy: a long-term follow-up study over 10 years. Spine (Phila Pa 1976), 2001, 26(13): 1443-1447.
46. Tsuzuki N, Abe R, Saiki K, et al. Extradural tethering effect as one mechanism of radiculopathy complicating posterior decompression of the cervical spinal cord. Spine (Phila Pa 1976), 1996, 21(2): 203-211.
47. Kong Q, Zhang L, Liu L, et al. Effect of the decompressive extent on the magnitude of the spinal cord shift after expansive open-door laminoplasty. Spine (Phila Pa 1976), 2011, 36(13): 1030-1036.
48. Sasai K, Saito T, Akagi S, et al. Preventing C5 palsy after laminoplasty. Spine (Phila Pa 1976), 2003, 28(17): 1972-1977.
49. Katsumi K, Yamazaki A, Watanabe K, et al. Can prophylactic bilateral C4/5 Foraminotomy prevent postoperative C5 palsy after open-door Laminoplasty? A prospective study. Spine (Phila Pa 1976), 2011. [Epub ahead of print].
50. Kaneyama S, Sumi M, Kanatani T, et al. Prospective study and multivariate analysis of the incidence of C5 palsy after cervical laminoplasty. Spine (Phila Pa 1976), 2010, 35(26): E1553-1558.
51. Hasegawa K, Homma T, Chiba Y. Upper extremity palsy following cervical decompression surgery results from a transient spinal cord lesion. Spine (Phila Pa 1976), 2007, 32(6): E197-202.
52. Sakaura H, Hosono N, Mukai Y, et al. Segmental motor paralysis after cervical laminoplasty: a prospective study. Spine (Phila Pa 1976), 2006, 31(23): 2684-2688.
53. Chiba K, Toyama Y, Matsumoto M, et al. Segmental motor paralysis after expansive open-door laminoplasty. Spine (Phila Pa 1976), 2002, 27(19): 2108-2115.
  1. 1. Kaplan L, Bronstein Y, Barzilay Y, et al. Canal expansive laminoplasty in the management of cervical spondylotic myelopathy. Isr Med Assoc J, 2006, 8(8): 548-552.
  2. 2. Edwards CC 2nd, Heller JG, Murakami H. Corpectomy versus laminoplasty for multilevel cervical myelopathy: an independent matched-cohort analysis. Spine (Phila Pa 1976), 2002, 27(11): 1168-1175.
  3. 3. Herkowitz HN. A comparison of anterior cervical fusion, cervical laminectomy, and cervical laminoplasty for the surgical management of multiple level spondylotic radiculopathy. Spine (Phila Pa 1976), 1988, 13(7): 774-780.
  4. 4. Klineberg E. Cervical spondylotic myelopathy: a review of the evidence. Orthop Clin North Am, 2010, 41(2): 193-202.
  5. 5. Kawaguchi Y, Matsui H, Ishihara H, et al. Axial symptoms after en bloc cervical laminoplasty. J Spinal Disord, 1999, 12(5): 392-395.
  6. 6. Ratliff JK, Cooper PR. Cervical laminoplasty: a critical review. J Neurosurg, 2003, 98(3 Suppl): 230-238.
  7. 7. Kotani Y, Abumi K, Ito M, et al. Minimum 2-year outcome of cervical laminoplasty with deep extensor muscle-preserving approach: impact on cervical spine function and quality of life. Eur Spine J, 2009, 18(5): 663-671.
  8. 8. Takeuchi K, Yokoyama T, Aburakawa S, et al. Axial symptoms after cervical laminoplasty with C3 laminectomy compared with conventional C3-C7 laminoplasty: a modified laminoplasty preserving the semispinalis cervicis inserted into axis. Spine (Phila Pa 1976), 2005, 30(22): 2544-2549.
  9. 9. Shiraishi T, Fukuda K, Yato Y, et al. Results of skip laminectomy-minimum 2-year follow-up study compared with open-door laminoplasty. Spine (Phila Pa 1976), 2003, 28(24): 2667-2672.
  10. 10. Nolan JP Jr, Sherk HH. Biomechanical evaluation of the extensor musculature of the cervical spine, Spine (Phila Pa 1976), 1988, 13(1): 9-11.
  11. 11. Han DW, Koo BN, Chung WY, et al. Preoperative greater occipital nerve block in total thyroidectomy patients can reduce postoperative occipital headache and posterior neck pain. Thyroid, 2006, 16(6): 599-603.
  12. 12. Sakaura H, Hosono N, Mukai Y, et al. Preservation of muscles attached to the C2 and C7 spinous processes rather than subaxial deep extensors reduces adverse effects after cervical laminoplasty. Spine (Phila Pa 1976), 2010, 35(16): E782-786.
  13. 13. Takeuchi K, Yokoyama T, Aburakawa S, et al. Postoperative changes at the lower end of cervical laminoplasty: for preservation of the C7 spinous process in laminoplasty. J Spinal Disord Tech, 2006, 19(6): 402-406.
  14. 14. Takeshita K, Seichi A, Akune T, et al. Can laminoplasty maintain the cervical alignment even when the C2 lamina is contained? Spine (Phila Pa 1976), 2005, 30(11): 1294-1298.
  15. 15. IizukaH, Shimizu T, Tateno K, et al. Extensor musculature of the cervical spine after laminoplasty: morphologic evaluation by coronal view of the magnetic resonance image. Spine (Phila Pa 1976), 26(20): 2220-2226.
  16. 16. Kato M, Nakamura H, Konishi S, et al. Effect of preserving paraspinal muscles on postoperative axial pain in the selective cervical laminoplasty. Spine (Phila Pa 1976), 2008, 33(14): E455-459.
  17. 17. Sakaura H, Hosono N, Mukai Y, et al. Preservation of muscles attached to the C2 and C7 spinous processes rather than subaxial deep extensors reduces adverse effects after cervical laminoplasty. Spine (Phila Pa 1976), 2010, 35(16): E782-786.
  18. 18. Fujibayashi S, Neo M, Yoshida M, et al. Neck muscle strength before and after cervical laminoplasty: relation to axial symptoms. J Spinal Disord Tech, 2010, 23(3): 197-202.
  19. 19. Hosono N, Sakaura H, Mukai Y, et al. C3-6 laminoplasty takes over C3-7 laminoplasty with significantly lower incidence of axial neck pain. Eur Spine J, 2006, 15(9): 1375-1379.
  20. 20. Ono A, Tonosaki Y, Yokoyama T, et al. Surgical anatomy of the nuchal muscles in the posterior cervicothoracic junction: significance of the preservation of the C7 spinous process in cervical laminoplasty. Spine (Phila Pa 1976), 2008, 33(11): E349-354.
  21. 21. Yasuoka S, Peterson HA, MacCarty CS. Incidence of spinal column deformity after multilevel laminectomy in children and adults. J Neurosurg, 1982, 57(4): 441-445.
  22. 22. Okada M, Minamide A, Endo T, et al. A prospective randomized study of clinical outcomes in patients with cervical compressive myelopathy treated with open-door or French-door laminoplasty. Spine (Phila Pa 1976), 2009, 34(11): 1119-1126.
  23. 23. Kowatari K, Ueyama K, Sannohe A, et al. Preserving the C7 spinous process with its muscles attached: effect on axial symptoms after cervical laminoplasty. J Orthop Sci, 2009, 14(3): 279-284.
  24. 24. Takeuchi K, Yokoyama T, Aburakawa S, et al. Anatomic study of the semispinalis cervicis for reattachment during laminoplasty. Clin Orthop Relat Res, 2005, (436): 126-131.
  25. 25. Liu J, Ebraheim NA, Sanford CG Jr, et al. Preservation of the spinous process-ligament-muscle complex to prevent kyphotic deformity following laminoplasty. Spine J, 2007, 7(2): 159-164.
  26. 26. Matsumoto M, Nojiri K, Chiba K, et al. Open-door laminoplasty for cervical myelopathy resulting from adjacent-segment disease in patients with previous anterior cervical decompression and fusion. Spine (Phila Pa 1976), 2006, 31(12): 1332-1337.
  27. 27. Albert TJ, Vacarro A. Postlaminectomy kyphosis. Spine (Phila Pa 1976), 1998, 23(24): 2738-2745.
  28. 28. Sciubba DM, Chaichana KL, Woodworth GF, et al. Factors associated with cervical instability requiring fusion after cervical laminectomy for intradural tumor resection. J Neurosurg Spine, 2008, 8(5): 413-419.
  29. 29. Katsumi Y, Honma T, Nakamura T. Analysis of cervical instability resulting from laminectomies for removal of spinal cord tumor. Spine (Phila Pa 1976), 1989, 14(11): 1171-1176.
  30. 30. Inoue A, Ikata T, Katoh S. Spinal deformity following surgery for spinal cord tumors and tumorous lesions: analysis based on an assessment of the spinal functional curve. Spinal Cord, 1996, 34(9): 536-542.
  31. 31. Steinbok P, Boyd M, Cochrane D. Cervical spinal deformity following craniotomy and upper cervical laminectomy for posterior fossa tumors in children. Childs Nerv Syst, 1989, 5(1): 25-28.
  32. 32. Zhang J, Hirabayashi S, Saiki K, et al. Effectiveness of multiple-level decompression in laminoplasty and simultaneous C1 laminectomy for patients with cervical myelopathy. Eur Spine J, 2006, 15(9): 1367-1374.
  33. 33. Takeshita K, Seichi A, Akune T, et al. Can laminoplasty maintain the cervical alignment even when the C2 lamina is contained? Spine (Phila Pa 1976), 2005, 30(11): 1294-1298.
  34. 34. Imagama S, Matsuyama Y, Yukawa Y, et al. C5 palsy after cervical laminoplasty: a multicentre study. J Bone Joint Surg (Br), 2010, 92(3): 393-400.
  35. 35. Roselli R, Pompucci A, Formica F, et al. Open-door laminoplasty for cervical stenotic myelopathy: surgical technique and neurophysiological monitoring. J Neurosurg, 2000, 92(1 Suppl): 38-43.
  36. 36. Yue WM, Tan CT, Tan SB, et al. Results of cervical laminoplasty and a comparison between single and double trap-door techniques. J Spinal Disord, 2000, 13(4): 329-335.
  37. 37. Edwards CC 2nd, Heller JG, Silcox DH 3rd. T-Saw laminoplasty for the management of cervical spondylotic myelopathy: clinical and radiographic outcome. Spine (Phila Pa 1976), 2000, 25(14): 1788-1794.
  38. 38. Satomi K, Ogawa J, Ishii Y, et al. Short-term complications and long-term results of expansive open-door laminoplasty for cervical stenotic myelopathy. Spine J, 2001, 1(1): 26-30.
  39. 39. Morio Y, Yamamoto K, Teshima R, et al. Clinicoradiologic study of cervical laminoplasty with posterolateral fusion or bone graft. Spine (Phila Pa 1976), 2000, 25(2): 190-196.
  40. 40. Satomi K, Nishu Y, Kohno T, et al. Long-term follow-up studies of open-door expansive laminoplasty for cervical stenotic myelopathy. Spine (Phila Pa 1976), 1994, 19(5): 507-510.
  41. 41. Jimenez JC, Sani S, Braverman B, et al. Palsies of the fifth cervical nerve root after cervical decompression: prevention using continuous intraoperative electromyography monitoring. J Neurosurg Spine, 2005, 3(2): 92-97.
  42. 42. Hirabayashi K, Toyama Y, Chiba K. Expansive laminoplasty for myelopathy in ossification of the longitudinal ligament. Clin Orthop Relat Res, 1999, (359): 35-48.
  43. 43. Uematsu Y, Tokuhashi Y, Matsuzaki H. Radiculopathy after laminoplasty of the cervical spine. Spine (Phila Pa 1976), 1998, 23(19): 2057-2062.
  44. 44. Minoda Y, Nakamura H, Konishi S, et al. Palsy of the C5 nerve root after midsagittal-splitting laminoplasty of the cervical spine. Spine (Phila Pa 1976), 2003, 28(11): 1123-1127.
  45. 45. Wada E, Suzuki S, Kanazawa A, et al. Subtotal corpectomy versus laminoplasty for multilevel cervical spondylotic myelopathy: a long-term follow-up study over 10 years. Spine (Phila Pa 1976), 2001, 26(13): 1443-1447.
  46. 46. Tsuzuki N, Abe R, Saiki K, et al. Extradural tethering effect as one mechanism of radiculopathy complicating posterior decompression of the cervical spinal cord. Spine (Phila Pa 1976), 1996, 21(2): 203-211.
  47. 47. Kong Q, Zhang L, Liu L, et al. Effect of the decompressive extent on the magnitude of the spinal cord shift after expansive open-door laminoplasty. Spine (Phila Pa 1976), 2011, 36(13): 1030-1036.
  48. 48. Sasai K, Saito T, Akagi S, et al. Preventing C5 palsy after laminoplasty. Spine (Phila Pa 1976), 2003, 28(17): 1972-1977.
  49. 49. Katsumi K, Yamazaki A, Watanabe K, et al. Can prophylactic bilateral C4/5 Foraminotomy prevent postoperative C5 palsy after open-door Laminoplasty? A prospective study. Spine (Phila Pa 1976), 2011. [Epub ahead of print].
  50. 50. Kaneyama S, Sumi M, Kanatani T, et al. Prospective study and multivariate analysis of the incidence of C5 palsy after cervical laminoplasty. Spine (Phila Pa 1976), 2010, 35(26): E1553-1558.
  51. 51. Hasegawa K, Homma T, Chiba Y. Upper extremity palsy following cervical decompression surgery results from a transient spinal cord lesion. Spine (Phila Pa 1976), 2007, 32(6): E197-202.
  52. 52. Sakaura H, Hosono N, Mukai Y, et al. Segmental motor paralysis after cervical laminoplasty: a prospective study. Spine (Phila Pa 1976), 2006, 31(23): 2684-2688.
  53. 53. Chiba K, Toyama Y, Matsumoto M, et al. Segmental motor paralysis after expansive open-door laminoplasty. Spine (Phila Pa 1976), 2002, 27(19): 2108-2115.