Comparison of the Effects of Posterior Cervical Fixation or Posterior Cervical Fixation Extending to the Upper Thoracic Region on Cervical Sagittal Alignment

Abstract

Objective: For degenerative diseases accompanied by cervical malalignment, the starting and ending points of fixation for better cervical sagittal alignment and clinical results are not as clear as the thoracolumbar region. In this study we aimed to compare the effects of posterior subaxial cervical fixation (PSCF), posterior cervical fixation extending to the upper thoracic region and posterior upper cervical fixation extending to the upper thoracic region on cervical sagittal alignment.

Methods: Sixty-three patients who underwent posterior cervical and cervical-up thoracic fixation were retrospectively analyzed in a comparative study. The procedures that we performed from May 2019 to March 2022 on these 63 patients were: (1) C3-C6 group—posterior subaxial cervical fixation; (2) Subaxial-T2 group—posterior subaxial cervicothoracic fixation (PSCTF); (3) C2-T2 upper thoracic posterior fixation group. The C3-C6 group had 27 patients, Subaxial-T2 group had 24, and C2-T2 group had 12. We determined the minimum follow-up period as 12 months. C0-2, C2-7 lordosis angle, sagittal vertical axis (SVA), C2 slope, C7 slope, T1 slope, cervical slope, neck slope, and thoracic inlet angle (TIA) measurements were made in three patient groups. Comparatively, cervical sagittal alignment was evaluated.

Result: In the C2-T2 group, a significant increase in C2-C7 lordosis, decrease in C2 slope, and increase in TS-CL were observed. Significant C2-C7 lordosis decrease, C2 slope increase, and TS-CL decrease were observed in the C3-C6 group. A significant increase in C2-C7 lordosis and a decrease in C2 slope were observed in the subaxial-T2 group. No significant change was observed in the TS-CL angle.

Conclusion: In cervical degenerative disorders accompanied by cervical malalignment, we recommend the C2-T2 fixation method, which provides the desired C2-C7 lordosis, SVA within the normal range, and the best Neck Disability Index results.

Keywords

Cervical Alignment / Cervical Balance / Lateral Mass Screw / Pedicle Screw

References

[1] Abelin-Genevois K. Sagittal balance of the spine. Orthop Traumatol Surg Res. 2021; 107(1S):102769.

[2] Li J, Zhang D, Shen Y. Impact of cervical sagittal parameters on axial neck pain in patients with cervical kyphosis. J Orthop Surg Res. 2020; 15(1): 434.

[3] Scheer JK, Tang JA, Smith JS, Acosta FL, Protopsaltis TS, Blondel B, et al. Cervical spine alignment, sagittal deformity, and clinical implications: a review. J Neurosurg Spine. 2013; 19(2): 141–159.

[4] Shimizu K, Nakamura M, Nishikawa Y, Hijikata S, Chiba K, Toyama Y. Spinal kyphosis causes demyelination and neuronal loss in the spinal cord: a new model of kyphotic deformity using juvenile Japanese small game fowls. Spine (Phila Pa 1976). 2005; 30(21): 2388–2392.

[5] Song QX, Su XJ, Wang K, Zhi-Chen , Quan-Li , Liu ZD, et al. Is complete correction of cervical sagittal malalignment necessary during 4-level anterior cervical discectomy and fusion surgery in patients with kyphosis? Global Spine J. 2023; 13(5): 1311–1318.

[6] Dru AB, Lockney DT, Vaziri S, Decker M, Polifka AJ, Fox WC, et al. Cervical spine deformity correction techniques. Neurospine. 2019; 16(3): 470–482.

[7] Blondel B, Schwab F, Bess S, Ames C, Mummaneni PV, Hart R, et al. Posterior global malalignment after osteotomy for sagittal plane deformity: it happens and here is why. Spine (Phila Pa 1976). 2013; 38(7): E394–E401.

[8] Hyun SJ, Kim KJ, Jahng TA, Kim HJ. Clinical impact of T1 slope minus cervical lordosis after multilevel posterior cervical fusion surgery: a minimum 2-year follow up data. Spine (Phila Pa 1976). 2017; 42(24): 1859–1864.

[9] Jeanneret B, Magerl F, Ward EH, Ward JC. Posterior stabilization of the cervical spine with hook plates. Spine (Phila Pa 1976). 1991; 16(3 Suppl): S56–S63.

[10] Hacker AG, Molloy S, Bernard J. The contralateral lamina: a reliable guide in subaxial, cervical pedicle screw placement. Eur Spine J. 2008; 17(11): 1457–1461.

[11] Harris CR, Millman KJ, van der Walt SJ, Gommers R, Virtanen P, Cournapeau D, et al. Array programming with NumPy. Nature. 2020; 585(7825): 357–362.

[12] Hunter JD. Matplotlib: a 2D graphics environment. Comput Sci Eng. 2007; 9(3): 90–95.

[13] Heary RF, Choudhry OJ, Jalan D, Agarwal N. Analysis of cervical sagittal alignment after screw-rod fixation. Neurosurgery. 2013; 72(6): 983–991; discussion 991–992.

[14] Martini ML, Neifert SN, Chapman EK, Mroz TE, Rasouli JJ. Cervical spine alignment in the sagittal Axis: a review of the best validated measures in clinical practice. Global Spine J. 2021; 11(8): 1307–1312.

[15] Roy-Camille R, Saillant G, Laville C, Benazet JP. Treatment of lower cervical spinal injuries–C3 to C7. Spine (Phila Pa 1976). 1992; 17(10 Suppl): S442–S446.

[16] An HS, Gordin R, Renner K. Anatomic considerations for plate-screw fixation of the cervical spine. Spine (Phila Pa 1976). 1991; 16(10 Suppl): S548–S551.

[17] Abumi K, Itoh H, Taneichi H, Kaneda K. Transpedicular screw fixation for traumatic lesions of the middle and lower cervical spine: description of the techniques and preliminary report. J Spinal Disord. 1994; 7(1): 19–28.

[18] Yukawa Y, Kato F, Suda K, Yamagata M, Ueta T. Age-related changes in osseous anatomy, alignment, and range of motion of the cervical spine. Part I: radiographic data from over 1, 200 asymptomatic subjects. Eur Spine J. 2012; 21(8): 1492–1498.

[19] Gore DR, Sepic SB, Gardner GM. Roentgenographic findings of the cervical spine in asymptomatic people. Spine (Phila Pa 1976). 1986; 11(6): 521–524.

[20] Smith JS, Lafage V, Ryan DJ, Shaffrey CI, Schwab FJ, Patel AA, et al. Association of myelopathy scores with cervical sagittal balance and normalized spinal cord volume: analysis of 56 preoperative cases from the AOSpine North America myelopathy study. Spine (Phila Pa 1976). 2013; 38(22 Suppl 1): S161–S170.

[21] Tang JA, Scheer JK, Smith JS, Deviren V, Bess S, Hart RA, et al. The impact of standing regional cervical sagittal alignment on outcomes in posterior cervical fusion surgery. Neurosurgery. 2012; 71(3): 662–669; discussion 669.

[22] Le Huec JC, Thompson W, Mohsinaly Y, Barrey C, Faundez A. Sagittal balance of the spine. Eur Spine J. 2019; 28(9): 1889–1905.

[23] Protopsaltis TS, Lafage R, Vira S, Sciubba D, Soroceanu A, Hamilton K, et al. Novel angular measures of cervical deformity account for upper cervical compensation and sagittal alignment. Clin Spine Surg. 2017; 30(7): E959–E967.

[24] Chai Z, Yang X, Lu H, Zhai Y, Zhang W, Yu H. Relationship between C2 slope with sagittal parameters and clinical function of degenerative cervical kyphosis. J Orthop Surg Res. 2023; 18(1): 514.

[25] Tamai K, Buser Z, Paholpak P, Sessumpun K, Nakamura H, Wang JC. Can C7 slope substitute the T1 slope?: an analysis using cervical radiographs and kinematic MRIs. Spine (Phila Pa 1976). 2018; 43(7): 520–525.

[26] Park JH, Cho CB, Song JH, Kim SW, Ha Y, Oh JK. T1 slope and cervical sagittal alignment on cervical CT radiographs of asymptomatic persons. J Korean Neurosurg Soc. 2013; 53(6): 356–359.

[27] Weng C, Wang J, Tuchman A, Wang J, Fu C, Hsieh PC, et al. Influence of T1 slope on the cervical sagittal balance in degenerative cervical spine: an analysis using kinematic MRI. Spine (Phila Pa 1976). 2016; 41(3): 185–190.

[28] Knott PT, Mardjetko SM, Techy F. The use of the T1 sagittal angle in predicting overall sagittal balance of the spine. Spine J. 2010; 10(11): 994–998.

[29] Kong C, Li XY, Sun XY, Guo MC, Ding JZ, Yang YM, et al. The ratio of C2-C7 cobb angle to T1 slope is an effective parameter for the selection of posterior surgical approach for patients with multisegmental cervical spondylotic myelopathy. J Orthop Sci. 2020; 25(6): 953–959.

[30] Lee SH, Kim KT, Seo EM, Suk KS, Kwack YH, Son ES. The influence of thoracic inlet alignment on the craniocervical sagittal balance in asymptomatic adults. J Spinal Disord Tech. 2012; 25(2): E41–E47.

[31] Lee S, Cho DC, Roh SW, Jeon SR, Moon EJ, Lee JJ, et al. Cervical alignment following posterior cervical fusion surgery: cervical pedicle screw versus lateral mass screw fixation. Spine (Phila Pa 1976). 2021; 46(10): E576–E583.

[32] Kothe R, Ruther W, Schneider E, Linke B. Biomechanical analysis of transpedicular screw fixation in the subaxial cervical spine. Spine (Phila Pa 1976). 2004; 29(17): 1869–1875.

[33] Abumi K, Shono Y, Taneichi H, Ito M, Kaneda K. Correction of cervical kyphosis using pedicle screw fixation systems. Spine (Phila Pa 1976). 1999; 24(22): 2389–2396.

[34] Duan Y, Wang HH, Jin AM, Zhang L, Min SX, Liu CL, et al. Finite element analysis of posterior cervical fixation. Orthop Traumatol Surg Res. 2015; 101(1): 23–29.

RIGHTS & PERMISSIONS

2024 The Author(s). Orthopaedic Surgery published by Tianjin Hospital and John Wiley & Sons Australia, Ltd.