The Morphometry of the Cervical Vertebral Column in the Sagittal Plane: Comparing Methods for Determining Cervical Lordosis Angle

Öz

Background: The aims of this study were to: (i) to analyze the morphometric characteristics of the cervical vertebral column in the sagittal plane; and (ii) compare morphometric methods used for determinating cervical lordosis angle. Materials and Methods: Direct cervical sagittal radiographs of 175 adults were analyzed and cervical lordosis angle was evaluated by Cobb (C2-C7), central cervical lordosis angle, posterior tangent, and Risser & Ferguson methods. In addition, occipitocervical angle (occiput-C2) and cervical vertical tranlation distance were deter-mined to assess upper cervical lordosis and forward head posture, respectively. Results: The measured cervical lordosis angles were differed (p<0.05) depending on the measurement met-hod. There was a strong negative correlation between cervical lordosis angle and occipitocervical angle (r = -0.707), a weak negative correlation between cervical lordosis angle and cervical vertical translation distance (r = -0.253) and a moderate positive correlation between occipitocervical angle and cervical vertical translation distance (r = 0.552). It was observed that an increase of 1 mm in the cervical vertical translation distance cau-sed an increase in the occipitocervical angle about 0.6 degrees. Conclusions: In planning cervical surgery, the balance and alignment of the cervical vertebral column in the sagittal plane should be evaluated in detail. The contour of the cervical vertebral column in the sagittal plane and the limits of cervical lordosis angle are important in the evaluation of cervical pathologies. The obsserva-tions from this study will benefit the understanding of vertebral column morphometry will contribute to the literature in anatomy, physiotherapy, radiology, and cervical regional surgery. Key Words: Cervical lordosis angle, cervical vertebrae, morphometry, radiography, sagittal plane

Anahtar Kelimeler

• Cervical lordosis angle
• cervical vertebrae
• morphometry
• radiography

Sagittal Düzlemde Servikal Vertebral Kolonun Morfometrisi: Servikal Lordoz Açısını Belirleme Yöntemlerinin Karşılaştırılması

Öz

Background: The aims of this study were to: (i) to analyze the morphometric characteristics of the cervical vertebral column in the sagittal plane; and (ii) compare morphometric methods used for determinating cervical lordosis angle. Materials and methods: Direct cervical sagittal radiographs of one 175 adults were analyzed and cervical lordosis angle was evaluated by Cobb (C2-C7), central cervical lordosis angle, posterior tangent, and Risser & Ferguson methods. In addition, occipitocervical angle (occiput-C2) and cervical vertical translation were determined to assess upper cervical lordosis and forward head posture, respectively. Results: The measured cervical lordosis angles were differed (p<0.05) depending on the measurement method. There was a strong negative correlation between cervical lordosis angle and occipitocervical angle (r = -0.707), a weak negative correlation between cervical lordosis angle and cervical vertical translation distance (r = -0.253) and a moderate positive correlation between occipitocervical angle and cervical vertical translation distance (r = 0.552). It was observed that an increase of 1 mm in the cervical vertical translation distance caused an increase in the occipitocervical angle about 0.6 degrees. Conclusions: In planning cervical surgery, the balance and alignment of the cervical vertebral column in the sagittal plane should be evaluated in detail. The contour of the cervical vertebral column in the sagittal plane and the limits of cervical lordosis angle are important in the evaluation of cervical pathologies. The obsservations from this study will benefit the understanding of vertebral column morphometry will contribute to the literature in anatomy, physiotherapy, radiology, and cervical regional surgery.

Anahtar Kelimeler

• Cervical lordosis angle
• cervical vertebrae
• morphometry
• radiography
• sagittal plane

Kaynakça

1. 1. DeSai C, Reddy V, Agarwal A. Anatomy, Back, Vertebral Column. In: StatPearls, Treasure Island (FL): StatPearls Pub-lishing [NBK525969] 2022 [cited 27 Feb 2023]. Available from: www.ncbi.nlm.nih.gov/books/NBK525969/.
2. 2. Waxenbaum JA, Reddy V, Futterman B. Anatomy, Back, Intervertebral Discs. In: StatPearls, Treasure Island (FL): StatPearls Publishing [NBK470583] 2022 [cited 27 Feb 2023]. Available from: www.ncbi.nlm.nih.gov/books/NBK470583/
3. 3. Miele VJ, Panjabi MM, Benzel EC. Anatomy and biomecha-nics of the spinal column and cord. Handb Clin Neurol. 2012;109:31-43.
4. 4. Erkan S, Yercan HS, Okcu G, Ozalp RT. The influence of sagittal cervical profile, gender and age on the thoracic kyp-hosis. Acta Orthop Belg. 2010;76(5):675-680.
5. 5. Xiaolong S, Xuhui Z, Jian C, Ye T, Wen Y. Weakness of the neck extensors, possible causes and relation to adolescent idiopathic cervical kyphosis. Med Hypotheses. 2011;77(3):456-459.
6. 6. Schomacher J, Falla D. Function and structure of the deep cervical extensor muscles in patients with neck pain. Man Ther. 2013;18(5):360-366.
7. 7. Oh C, Lee M, Hong B, Song BS, Yun S, Kwon S, et al. Associa-tion between Sagittal Cervical Spinal Alignment and Dege-nerative Cervical Spondylosis: A Retrospective Study Using a New Scoring System. J Clin Med. 2022;11(7):1772.
8. 8. Hwang JH, Modi HN, Suh SW, Hong JY, Park YH, Park JH, et al. Reliability of lumbar lordosis measurement in patients with spondylolisthesis: a casecontrol study comparing the Cobb, centroid, and posterior tangent methods. Spine (Phi-la Pa 1976). 2010;35(18):1691-1700.

9. 9. Kim D, Davis DD, Menger RP. Spine Sagittal Balance. In: StatPearls, Treasure Island (FL): StatPearls Publishing [NBK534858] 2022 [cited 27 Feb 2023]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534858/.
10. 10. Anderson R. Human evolution, low back pain. Evolutionary medicine. 1999:333.
11. 11. Helliwell PS, Evans PF, Wright V. The straight cervical spine: does it indicate muscle spasm? J Bone Joint Surg Br. 1994;76(1):103-106.
12. 12. Suvarnnato T, Puntumetakul R, Uthaikhup S, Boucaut R. Effect of specific deep cervical muscle exercises on functio-nal disability, pain intensity, craniovertebral angle, and neck-muscle strength in chronic mechanical neck pain: a randomized controlled trial. J Pain Res. 2019;12:915-925.
13. 13. Oakley PA, Ehsani NN, Moustafa IM, Harrison DE. Restoring cervical lordosis by cervical extension traction methods in the treatment of cervical spine disorders: a systematic re-view of controlled trials. J Phys Ther Sci. 2021;33(10):784-794.
14. 14. Liu J, Liu P, Ma Z, Mou J, Wang Z, Sun D, et al. Age-related changes in cervical sagittal range of motion and alignment. Global Spine J. 2014;4(3):151-156.
15. 15. Gore DR, Sepic SB, Gardner GM. Roentgenographic findings of the cervical spine in asymptomatic people. Spine (Phila Pa 1976). 1986;11(6):521-524.
16. 16. Yukawa Y, Kato F, Suda K, Yamagata M, Ueta T. Age-related changes in osseous anatomy, alignment, and range of mo-tion of the cervical spine. Part I: Radiographic data from over 1,200 asymptomatic subjects. Eur Spine J. 2012;21(8):1492-1498.
17. 17. Park MS, Moon SH, Lee HM, Kim TH, Oh JK, Nam JH, et al. Age-related changes in cervical sagittal range of motion and alignment. Global Spine J. 2014;4(3):151-156.
18. 18. Nojiri K, Matsumoto M, Chiba K, Maruiwa H, Nakamura M, Nishizawa T, et al. Relationship between alignment of up-per and lower cervical spine in asymptomatic individuals. J Neurosurg. 2003;99(1 Suppl):80-83.
19. 19. Tang R, Ye IB, Cheung ZB, Kim JS, Cho SK. Age-related Chan-ges in Cervical Sagittal Alignment: A Radiographic Analysis. Spine (Phila Pa 1976). 2019;44(19):E1144-E1150.
20. 20. Harrison DD, Janik TJ, Troyanovich SJ, Holland B. Compari-sons of lordotic cervical spine curvatures to a theoretical id-eal model of the static sagittal cervical spine. Spine (Phila Pa 1976). 1996;21(6):667-675.
21. 21. Gwinn DE, Iannotti CA, Benzel EC, Steinmetz MP. Effective lordosis: analysis of sagittal spinal canal alignment in cervical spondylotic myelopathy. J Neurosurg Spine. 2009;11(6):667-672.
22. 22. Boy FNS, Özkan FÜ, Erdem S, Özdemir G, Külcü DG, Akpınar P, Aktaş İ. Servikal lordoz açıları ve boyun ağrısı ilişkisinin de-ğerlendirilmesi. Marmara Medical Journal. 2014;27(2):112-115.
23. 23. Silber JS, Lipetz JS, Hayes VM, Lonner BS. Measurement variability in the assessment of sagittal alignment of the cervical spine: a comparison of the gore and cobb methods. J Spinal Disord Tech. 2004;17(4):301-305.
24. 24. Ohara A, Miyamoto K, Naganawa T, Matsumoto K, Shimizu K. Reliabilities of and correlations among five standard met-hods of assessing the sagittal alignment of the cervical spi-ne. Spine (Phila Pa 1976). 2006;31(22):2585-2591; discussion 2592.
25. 25. Donk RD, Fehlings MG, Verhagen WIM, Arnts H, Groe-newoud H, Verbeek ALM, et al. An assessment of the most reliable method to estimate the sagittal alignment of the cervical spine: analysis of a prospective cohort of 138 cases. J Neurosurg Spine. 2017;26(5):572-576.
26. 26. Guo Q, Ni B, Yang J, Liu K., Sun Z, Zhou F, et al. Relation between alignments of upper and subaxial cervical spine: a radiological study. Arch Orthop Trauma Surg. 2011;131(6):857-862
27. 27. Sherekar SK, Yadav YR, Basoor AS, Baghel A, Adam N. Clini-cal implications of alignment of upper and lower cervical spine. Neurol India. 2006;54(3):264-267.
28. 28. Roussouly P, Nnadi C. Sagittal plane deformity: an overview of interpretation and management. Eur Spine J. 2010;19(11):1824-1836.
29. 29. Patel PD, Arutyunyan G, Plusch K, Vaccaro A, Jr., Vaccaro AR. A review of cervical spine alignment in the normal and degenerative spine. J Spine Surg. 2020;6(1):106-123.
30. 30. McAviney J, Schulz D, Bock R, Harrison DE, Holland B. De-termining the relationship between cervical lordosis and neck complaints. J Manipulative Physiol Ther. 2005;28(3):187-193.