Lumbar Pedicle Morphometry in the Mexican Population: Defining Anatomical References for Safer Spine Surgery

Pedicle screw fixation is a fundamental technique in spine surgery that requires precise knowledge of lumbar pedicle morphology to ensure safe and effective instrumentation. Pedicle dimension variations are influenced by sex, age, and ethnicity.

This retrospective observational study analyzed 185 lumbar vertebrae (L1-L5) from the CT scans of 37 adult patients without structural spinal pathologies. Bilateral measurements of pedicle width, height, length, and transverse angle, as well as vertebral body length, width, and height, were obtained using digital measurement tools. Statistical comparisons were performed by sex and age, with significance determined using independent t-tests and Spearman's correlations.

The pedicle width increased from L1 (7.0 mm) to L5 (11.8 mm), whereas the pedicle height decreased in the caudal direction. The transverse pedicle angle widened from L1 (16.8°) to L5 (21.9°). Males exhibited significantly greater pedicle width and length than females (p < 0.01), whereas vertebral body dimensions showed no significant sex-based differences. Age correlated negatively with pedicle height and angle (Rho ≈ -0.27 to -0.30), suggesting anatomical remodeling with age. No correlation was found between age and the dimensions of the vertebral bodies.

This study is among the first to provide detailed lumbar morphometric data for a Latin American population, specifically the Mexican population. These findings align with global trends and highlight the importance of considering population-specific anatomical differences during surgical planning.