Purpose: To evaluate upper sacral morphology and anatomy of safe zone related to iliosacral screw fixation in Korean. Materials and Methods: 100 patients performed pelvis 3D CT scan were evaluated. We used 16channel CT and analyzed reconstructed image...
Purpose: To evaluate upper sacral morphology and anatomy of safe zone related to iliosacral screw fixation in Korean. Materials and Methods: 100 patients performed pelvis 3D CT scan were evaluated. We used 16channel CT and analyzed reconstructed image (shaded-surface display, transparent image and reform at image). Results: The angle between superior aspect of S1 body and iliac cortical density is 27.3˚, between anterior cortical line of S1,2 body and horizontal plane 24.6˚, and between superior aspect of S1 body and horizontal plane is 39.7˚. The axis of S1, S2 pedicle is 32.5˚ and 15.6˚ toward anteroom edial. The area of S1 pedicle according to sagittal plane and sagittal-oblique axis is 310.7㎟ and 384.8㎟. Also, S2 pedicle area is increased 163.1㎟ to 188.4㎟. The average depth of ala indentation is 5.1 ㎜ and the maxim al value is 9.5 ㎜. Distinct upper sacral dysplasia is 22%, transitional form is 32%. Conclusion: We measured Korean upper sacrum with 3D-CT, found out dysplasia come up to 54%. Considering the frequency of dysplasia, the investigation of anatomy and technique is essential to sacroiliac screw insertion.