The relationship between the ratio of interpedicular distance increase and the ratio of spinal canal compromise in thoracolumbar burst fractures

BACKGROUND: The aim of the study was to investigate the relationship between the interpedicular distance increase ratio and the ratio of canal compromise in thoracolumbar burst fractures. METHODS: Thirty-one patients (18 male and 13 female) with an average age of 30.8 (14–57) who had been treated for thoracolumbar burst fractures in the Department of Orthopaedics and Traumatology were included in the study. The initial anteroposterior radiographs of the patients were used to calculate the increase ratio of interpedicular distance (both from medial-to-medial and from center-to-center). The area measurements from the computerized tomography or magnetic resonans images were used to calculate the canal compromise. The relationship between the increase ratio of interpedicular distance and the ratio of canal compromise was investigated by correlation and linear regression analysis. RESULTS: There was a “very good” correlation between the from medial-to-medial and from center-to-center measurements of interpedicular distance (Pearson correlation coefficient: 0.89, p<0.001). The correlation between the ratio of canal compromise and from medial-to-medial and from center-to-center measurements of interpedicular distance was “good” with Pearson correlation coefficients of 0.60 and 0.63, respectively (p<0.001). No statistically significant relationships were found between the fracture levels, types, neurologic status of the patients, and the increase ratio of interpedicular distance or the ratio of canal compromise. CONCLUSION: Depending on the correlation coefficients which were obtained in this study: To predict the canal compromise from the ratio of interpedicular distance increase is not a reliable method for all of the patients.