Level-Wise and Bilateral Morphometry of the Adult Lumbar Vertebral Column in a Central Indian Population: A Cross-Sectional Osteometric Study

Abstract

Purpose: Population-specific morphometric data for the adult lumbar vertebral column remain absent for the Madhya Pradesh and Central Indian population. Existing regional data are restricted either to vertebral body and angular parameters alone or to pedicle dimensions alone, from small, non-power-calculated samples. This study aimed to generate a comprehensive, level-wise morphometric database of the adult lumbar vertebral column in this population.

Methods: A cross-sectional osteometric study was conducted on 110 dry adult human lumbar vertebrae (22 at each of L1-L5) drawn from a departmental osteology collection. Nine linear parameters, vertebral body height, transverse width, and antero-posterior length; right and left pedicle width; interpedicular distance; vertebral canal antero-posterior and transverse diameter; and spinous process length, were measured in triplicate using a digital Vernier caliper. Level-wise differences were tested by one-way ANOVA with Tukey's post-hoc test; bilateral (right-left) pedicle width symmetry was tested by paired t-test and Pearson correlation.

Results: All nine parameters increased significantly from L1 to L5 (p < .001 for each), pedicle width showing the largest proportional increase (8.05 mm to 12.92 mm on the right, a 60.5% increase). Vertebral body transverse width showed a fully stepwise gradient (all ten pairwise level comparisons significant), whereas vertebral body height and spinous process length showed a more gradual, level-clustered pattern. Right and left pedicle width did not differ significantly (mean difference 0.02 ± 0.42 mm; t(109) = 0.48, p = .634) and were strongly correlated (r = .971, p < .001).

Conclusion: The adult lumbar vertebral column in this Central Indian population shows a consistent cranio-caudal morphometric gradient and marked bilateral pedicle symmetry, with absolute dimensions generally smaller than Western reference data. These level-specific normative values provide a population-appropriate reference for transpedicular screw sizing and radiological assessment of the lumbar spine in Central India.