2.Minimally invasive fixation with virtual self-designed screws between the iliac plates for acetabular posterior column fractures: an anatomic study
Liangwen XIE ; Jianchun LIN ; Ruiren LIU ; Zhongguo LIU ; Lei CHEN
Chinese Journal of Orthopaedic Trauma 2024;26(9):810-817
Objective:To study the minimally invasive fixation with virtual self-designed screws between the iliac plates for acetabular posterior column fractures and compare the differences between genders.Methods:The CT data were collected from the 80 patients with normal pelvis who had undergone pelvic CT scan due to physical examination or trauma at Department of Orthopaedics, The Third Hospital of Xiamen from June 2021 to June 2022. There were 40 males and 40 females with an age of (45.0±12.4) years. The virtual screws between the minimally invasive iliac plates were designed with design software after 3D modeling. The insertion point, screw length, screw diameter, angle between the screw and the coronal plane of the pelvis, angle between the screw and the sagittal plane of the pelvis, angle ε between the screw and the anterior edge bone crest line of the greater sciatic notch, and bone channel volume were measured. Comparisons of the above data were made between genders. Results:The insertion point of the screw between the minimally invasive iliac plates was located between the anterior superior iliac spine and the iliac tubercle nodule, going toward the area between the ischial spine and the small ischial notch. The screw length was (139.64±8.46) mm, the screw diameter (8.95±1.16) mm, and the bone channel volume (51.91±10.77) cm 3. The screw length [144.34±7.58) mm], screw diameter [9.50±0.98) mm], angle between the screw and the sagittal plane of the pelvis (31.14°±2.74°), and bone channel volume [(57.82±8.82) cm 3] for males were significantly larger than those for females [(134.95±6.48) mm, (8.40±1.07) mm, 26.72°±2.74°, and (46.01±9.22) cm 3], while the angle between the screw and the sagittal plane of the pelvis [(35.74°±3.85°) mm] and angle ε between the screw and the anterior edge bone crest line of the greater sciatic notch (11.96°±4.57°) for males were significantly smaller than those for females (36.89°±2.96° and 14.17°±5.15°) (all P < 0.05). Conclusions:Fixation with screws between the iliac plates provides a new treatment for acetabular posterior column fractures, because the screws can be placed percutaneously in a minimally invasive manner or antegradely. The screw length, screw diameter, angle between the screw and the sagittal plane of the pelvis, and bone channel volume for males are significantly larger than those for females, while the angle between the screw and the sagittal plane of the pelvis and the angle between the screw and the anterior edge bone crest line of the greater sciatic notch for males are significantly smaller than those for females. Therefore, the angles between the iliac plate screw and the sagittal and coronal planes of the pelvis should be adjusted according to gender in screw placement.