Incidence of sacral dysmorphism among egyptian population, anatomic determinants and implication for sacroiliac screw fixation /
تحديد نسبة انتشار التشوه العجزي بين المصريين والمحددات التشريحية لخلل التشوه العجزي وتأثيرها علي وضع المسمار الحرقفي العجزي بشكل آمن
by Mahmoud Maher Mostafa ; Supervisors Dr. Walid Asharf Elnahal, Dr. Ahmed Gouda Ali Elhamalawy, Dr. Rania Ali Elzaitoun.
- 139 pages : illustrations ; 25 cm. + CD.
Thesis (M.Sc)-Cairo University, 2025.
Bibliography: pages 126-139.
Background: Percutaneous iliosacral screw fixation is the current gold standard for treating posterior pelvic ring injuries. However, screw misplacement occurs in up to 15% of cases, potentially causing neurovascular complications. This issue is closely linked to the orientation and size of safe fixation corridors in dysmorphic sacra, where abnormalities in the upper sacral segment increase the risk of cortical perforation during screw placement. Dysmorphic sacra are characterized by narrow and angled upper osseous corridors, the pelvis was reviewed for qualitative features and quantitatively using specific anatomical measurements. Broad objective: To evaluate qualitative and quantitative characteristics of sacral dysmorphism as well as the prevalence of sacral dysmorphism in Egypt. Study design and site: This was cross sectional prospective study carried out at the radiology department at Kasr Alainy Hospital at Cairo University. Methodology: For this study, 1,000 pelvic CT scans meeting the inclusion and exclusion criteria were evaluated for six qualitative features of upper sacral segment dysplasia from March 2024 to December 2024. The CT images were reformatted to measure the width of the osseous corridors. Data collected included qualitative features of sacral dysmorphism and objective measurements, such as S1 and S2 corridor diameters, to assess their correlation with sacral dysmorphism. Results: Sacral dysmorphism (SDM) was found in 19% of Egyptians, with mammillary processes (81.6%) and residual upper disc space (80%) being the most prevalent features. Combined patterns, such as “mammillary processes, residual upper disc space, and acute alar slope,” appeared in 23.7% of cases. SDM was more common in females (34.7% vs. 26.3%, p=0.02). S1 corridors were narrower, while S2 corridors were wider in SDM cases compared to normal subjects, with significant differences in measurements. Notch prevalence varied slightly between groups. Conclusion: In the Egyptian population, sacral dysmorphism (SDM) was identified in 19% of cases, with mammillary processes being the most common feature (81.6%). Females were affected more often than males (34.7% vs. 26.3%, p=0.02). SDM cases exhibited narrower S1 corridors and wider S2 corridors compared to normal individuals. العجز هو العنصر الأساسي في الحزام الحوضي ويتعرض لضغوط عالية مما يجعل كسوره عادة معقدة. لذلك، من المهم استعادة تركيبه التشريحي والميكانيكي بدقة عالية، مما يجعل علاجه تحديًا كبيرًا. تُعتبر كسور العجز شائعة في إصابات الحلقة الحوضية، بنسبة حدوث (30-45%). غالبًا ما يتم التقليل من تشخيص هذه الكسور وعلاجها، مما قد يؤدي إلى اختلالات عصبية. ترتبط اضطرابات الحلقة الحوضية الخلفية بمضاعفات خطيرة، بما في ذلك الألم المزمن، والاختلالات الجنسية، ومشاكل المثانة والأمعاء، وانخفاض القدرة على العودة إلى العمل. التثبيت العجزي الحرقفي عن طريق الجلد يعد تقنية صعبة تقنيًا، حيث يُعتبر الخطأ في وضع المسامير من أبرز المضاعفات، مما قد يؤدي إلى إصابات عصبية أو وعائية مُفتعلة. تعتمد هذه التقنية بشكل كبير على وجود تشريح طبيعي للعجز. يشير مصطلح "تشوهات العجز" إلى اختلافات غير طبيعية في الشرائح العجزية العلويه، مما قد يُشكل ممرات عظمية ضيقة أو أكثر ميلًا، مما يُقيد وضع مسامير العجز بأمان.