Abstract
BACKGROUND: Sacral fractures are associated with high-energy trauma and pose challenging surgical conditions due to anatomical variability. The presence of sacral dysmorphism with narrow corridors, acute alar slopes, and non-circular foramina further complicates the placement of ilio-sacral and trans-sacral screws. Gender-related differences also exist in sacral morphology, which can impact surgical planning and screw trajectory. METHODS: We reviewed data from 1000 pelvic CT scans among 652 males and 348 females aged 18-65 years from multiple centers to measure sacral morphometry along with the safe screw placement corridors. Quantification of S1 and S2 sacral segments was done using HOROS, Radiant, Iplan software tools in terms of anteroposterior breadth, height, and width of sacral corridors. The safe screw trajectory for 6.5 mm and 7.3-mm screws was established from the vestibular concept with 2 mm of safety margin. SPSS v22.0 was used for statistical analysis. RESULTS: Sacral dysmorphism was found in 31.58 % males and 18.42 % females. Male dimensions of the sacrum were higher, more sagittal height at S1 (12.01 ± 1.83 mm vs. 10.76 ± 1.13 mm, p < 0.001), and axial width (23.66 ± 3.32 mm vs. 13.3 ± 2.9 mm, p < 0.001), compared to women. Measurements made at S2 were similar among genders. Safe placement of 7.3 mm S1 trans-sacral screws was possible in 84.21 % males and 47.37 % females, and 6.5 mm screws were applicable in 10.53 % of males and 26.32 % of females. For S2, 68.42 % of males and 31.58 % females were amenable to 7.3 mm screws, while 6.5 mm screws were feasible in 10.53 % of males and 23.68 % of females. Dysmorphic sacrum required a specific approach with a bias towards the use of 6.5 mm screws. CONCLUSION: The study highlights gender variations and sacral dysmorphism impacts the safety of screw placement in Indian patients. The possibility of individualized planning before surgery by CT-based morphometry will improve safety as well as effectiveness in sacral fracture fixation.