A comparison of lumbar transverse pedicle angles between ethnic groups: a retrospective review

BACKGROUND: Spinal surgery requires an intimate understanding of pedicle morphology to provide safe and effective outcomes. Although current research has attempted to identify morphological vertebral pedicle trends, no study has utilized computed tomography (CT) scans to compare the lumbar transverse pedicle angle (TPA) with patient demographics factors in a diverse population throughout multiple hospital centers. METHODS: Analysis of randomly selected CT scans from L1-L5 of 97 individuals who underwent imaging over a two-week period for non-back pain related complaints was conducted. Measuring 970 TPAs in total allowed for comparison of each patients’ pedicle angle with important patient specific demographics including ethnicity, age, gender, height and weight. Statistical analysis utilized multiple comparisons of demographics at each level with post-hoc Bonferroni correction analysis to compare demographics at each level. RESULTS: With relation to gender, age, height or weight, no statistically significant differences were identified for TPAs at any vertebral level. However, when stratified by ethnicity, the differences in transverse pedicle angles averages (TPA –Avg) at L2 and L3 were found to be statistically significant (p < 0.05). CONCLUSION: We have identified a previously unknown and significant relationship between ethnicity and TPA at lumbar vertebral levels. These findings provide critical information that may be added to the operating surgeons’ knowledge of pedicle morphology. We hope this novel information can assist in preoperative planning of pedicle screw placement and potentially help improve surgical outcomes.