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Abstract

Background: Transpedicular screw fixation has been widely used for spinal reconstruction because of its good fusion results. However, pedicle walls can be damaged during fixation if diameter of the screw is too large or screw is misplaced. Knowledge of the morphometric dimensions of the pedicle is thus important for effective fixation and to avoid complications. The main objective of this study was to measure the Pedicle Transverse Diameter (PTD), Pedicle Vertical Diameter (PVD) and chord length of male adult cadavers from Zimbabwean population.Material and Methods: It was a descriptive cross-sectional study carried out at the Department of Anatomy, University of Zimbabwe College of Health Sciences, Harare Zimbabwe, from June 2019 to December 2019. The lumbar vertebrae from 15 adult male cadavers were dissected out and Pedicle Transverse Diameter (PTD), Pedicle Vertical Diameter (PVD) and chord length was measured and compared (on right and left sides), using a Vernier caliper. The statistical analysis was done using SPSS version 20.0., with data expressed as means, standard deviation and ranges. Student’s t-test was used to estimate the difference in pedicle dimensions of the right and left sides of the lumbar vertebrae.Results: There was an insignificant difference between pedicle dimensions (PTD and PVD) of the right and left sides (P > .05). PTD steadily increased from vertebral level L1 to L5 followed by an abrupt increase at L5. PVD gradually decreased from L1 to L5 level. The chord length increased from a minimum at L1 to reach a maximum at L3 and then again decreased to L5 level.Conclusions: Pedicle dimensions of the Zimbabwean population differ from those reported in previous studies for other population groups and can be useful while performing pedicle screw fixation for lumbar vertebral fractures. A screw length of 40-45 mm should be used for lumbar transpedicular screw fixation with minimal risk of implant failure in Zimbabwean population.