International Journal of Clinical Science and Medical Research

Background: Sagittal balance is a critical determinant of spinal health, with spinopelvic parameters varying across ethnic populations. Normative values for West African populations are lacking. This study aimed to measure sagittal balance parameters in Nigerian patients with chronic back pain and compare them with previously reported values from the same institution.

Methods: A cross‑sectional study of 473 consecutive patients (270 male, 203 female) with chronic back pain was conducted at the National Orthopaedic Hospital Dala, Kano, from January 2020 to December 2025. Standing whole‑spine lateral radiographs were obtained. Sagittal parameters measured included: sagittal vertical axis (SVA), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and T9 sagittal offset. Pain severity was assessed using the Visual Analogue Scale (VAS) and disability using the Oswestry Disability Index (ODI). Pearson correlation and multivariate regression analyses were performed.

Results: The mean age was 48.6±12.4 years. The measured parameters were: LL 52.4±10.8°, SS 36.8±7.6°, PT 17.5±7.2°, PI 53.8±10.2°, and T9 sagittal offset 10.2±3.1°. Compared with previously published values (LL 56±8.2°, SS 38±6.2°, PT 16±7.4°, PI 51±9.6°, T9 offset 9.4±2.7°), our cohort showed slightly lower LL and SS but higher PI and PT. SVA correlated moderately with VAS (r=0.42, p<0.001) and ODI (r=0.38, p<0.001). PI‑LL mismatch >10° was present in 22.6% of patients and was associated with significantly higher VAS (6.8±1.5 vs 4.9±1.8, p<0.001) and ODI (58.4±14.2 vs 42.3±16.5, p<0.001).

Conclusions: Sagittal balance parameters in Nigerian patients with back pain differ from previously reported local norms, with a trend towards higher PI and PT. PI‑LL mismatch is strongly associated with pain severity and disability. These findings underscore the importance of population‑specific reference values for surgical planning.

Sagittal balance, spinopelvic parameters, back pain, pelvic incidence, lumbar lordosis, Nigeria

1. GBD 2021 Low Back Pain Collaborators. Global, regional, and national burden of low back pain, 1990–2020: a systematic analysis for the Global Burden of Disease Study 2021. Lancet Rheumatol. 2023;5(6):e316-e329.
2. Hartvigsen J, Hancock MJ, Kongsted A, Louw Q, Ferreira ML, Genevay S, et al. What low back pain is and why we need to pay attention. Lancet. 2018;391(10137):2356-2367.
3. Omokhodion FO, Umar US, Ogunnowo BE. Prevalence of low back pain among staff in a Nigerian university. J Public Health. 2020;42(2):e123-e129.
4. Nwankwo OE, Uche EO. Epidemiology and treatment profile of spinal disorders in a tertiary hospital in Southeast Nigeria. Spinal Cord. 2013;51(6):448-52.
5. Schwab F, Patel A, Ungar B, Farcy JP, Lafage V. Adult spinal deformity–postoperative standing imbalance: how much can you tolerate? An overview of key parameters in assessing alignment and planning corrective surgery. Spine. 2010;35(25):2224-2231.
6. Glassman SD, Bridwell K, Dimar JR, Horton W, Berven S, Schwab F. The impact of positive sagittal balance in adult spinal deformity. Spine. 2005;30(18):2024-2029.
7. Le Huec JC, Hasegawa K. Normative values of the sagittal spinal balance: a systematic review. Eur Spine J. 2016;25(3):716-724.
8. Roussouly P, Gollogly S, Berthonnaud E, Dimnet J. Classification of the normal variation in the sagittal alignment of the human lumbar spine and pelvis in the standing position. Spine. 2005;30(3):346-353.
9. Dubousset J. Three‑dimensional analysis of the scoliotic deformity. In: Weinstein SL, editor. The pediatric spine: principles and practice. New York: Raven Press; 1994. p. 479-496.
10. Lafage V, Schwab F, Patel A, Hawkinson N, Farcy JP. Pelvic tilt and truncal inclination: two key radiographic parameters in the setting of adults with spinal deformity. Spine. 2009;34(17):E599-E606.
11. Schwab F, Farcy JP, Bridwell K, Berven S, Glassman S, Harrast J, et al. A clinical impact classification of scoliosis in the adult. Spine. 2006;31(18):2109-2114.
12. Legaye J, Duval-Beaupère G, Hecquet J, Marty C. Pelvic incidence: a fundamental pelvic parameter for three‑dimensional regulation of spinal sagittal curves. Eur Spine J. 1998;7(2):99-103.
13. Duval-Beaupère G, Schmidt C, Cosson P. A Barycentremetric study of the sagittal shape of spine and pelvis: the conditions required for an economic standing position. Ann Biomed Eng. 1992;20(4):451-462.
14. Roussouly P, Pinheiro-Franco JL. Sagittal parameters of the spine: biomechanical approach. Eur Spine J. 2011;20(Suppl 5):578-585.
15. Schwab F, Lafage V, Patel A, Farcy JP. Sagittal plane considerations and the pelvis in the adult patient. Spine. 2009;34(17):1828-1833.
16. Protopsaltis T, Schwab F, Bronsard N, Smith JS, Klineberg E, Mundis G, et al. The T1 pelvic angle, a novel radiographic measure of global sagittal deformity, accounts for both spinal inclination and pelvic tilt and correlates with health‑related quality of life. J Bone Joint Surg Am. 2014;96(19):1631-1640.
17. Kawu AA, Olawepo A, Salami OOA, Kuranga SA. Spinal sagittal alignment and balance in normal Nigerian. GP46. Spine: Affiliated Society Meeting Abstracts: October 2011
18. Tarrant RC, O’Loughlin PF, Lynch S, Given E, Queally JM, Moore D, et al. Sagittal spinal profile of a healthy black African population: an observational study. Eur Spine J. 2017;26(6):1686-1693.
19. Meissner W, Rohlmann A, Bergmann G. Are there ethnic differences in pelvic incidence? A systematic review. Spine J. 2022;22(5):812-820.
20. Schwab F, Ungar B, Blondel B, Buchowski J, Coe J, Deinlein D, et al. Scoliosis Research Society‑Schwab adult spinal deformity classification: a validation study. Spine. 2012;37(12):1077-1082.
21. Schwab F, Lafage V, Shaffrey CI, Smith JS, Ames CP, Bess S, et al. The Schwab adult spinal deformity classification: a new classification and its validation. Spine. 2012;37(22):1917-1925.
22. Gelb DE, Lenke LG, Bridwell KH, Blanke K, McEnery KW. An analysis of sagittal spinal alignment in 100 asymptomatic middle and older aged volunteers. Spine. 1995;20(12):1351-1358.
23. Hammerberg EM, Wood KB. Sagittal profile of the elderly. J Spinal Disord Tech. 2003;16(1):44-51.
24. Ferrero E, Obeid I, Larrieu D, Boissière L, Bourghli A, Pointillart V, et al. Ethnic differences in sagittal spinal and pelvic parameters: a systematic review. Eur Spine J. 2021;30(10):2798-2810.
25. Copay AG, Glassman SD, Subach BR, Berven S, Schuler TC, Carreon LY. Minimum clinically important difference in lumbar spine surgery patients: a choice of methods using the Oswestry Disability Index. Spine J. 2008;8(6):968-974.