髋臼后柱安全置钉的临床解剖学研究

Clinical Anatomy Study of Screw Placement Into Posterior Column of Acetabulum Security

目的探讨髋臼后柱的解剖结构,以寻求一安全的置钉途径。方法取15具骨盆标本(共30髋),确定髋臼缘最上点为A点,最下点为B点,取其A、B中点为C点。取坐骨大切迹顶点为A'点,坐骨棘顶点为B'点,取A'、B'中点为C'点。连接C、C'两点。经过C、C'线且与后柱表面垂直的平面为起始平面(髋臼中部平面)。平行于起始平面,在起始平面上下各作2个横断面,段面间隔为10mm。共获得包括髋臼前柱、后柱在内的5个断面。在每一断面上测量髋臼宽、后柱宽并测量距髋臼缘10、20mm处置入螺钉的安全角度和长度。测量结果用(x±s)表示。结果①髋臼中部平面髋臼最宽为:(20.7±1.5)mm。但该断面后柱最窄为:(33.9±2.5)mm。②距髋臼后缘10mm的各断面进钉的最小角度为(52.3±5.5)°,最小进钉长度为(28.9±2.7)mm。距髋臼后缘20mm的各断面进钉的最小角度为(81.4±5.0)°,最小进钉长度为(35.9±4.1)mm。结论在髋臼后柱距臼缘10、20mm处角度分别不大于50°、80°,深度分别不大于28、35mm可以安全的放置螺钉。

Objective To explore a safe path for screw placement into the acetabular posterior column during the procedure of open reduction and internal fixation of the acetabulum fractures through anatomical study of the posterior column of acetabulum. Methods Fivteen adult pelvis （30 hips） specimens were used in this study. The top point of acetabular margin was named point A, the fundus point of acetabular margin point B, the midpoint of line A-B C.The top point of greater sciatic notch was named A′, the top point of sciatic spina point B′,the midpoint of line A′-B′ C′.The original plane（middle plane of acetabulum）was through point C and C＇and perpendicular to the surface of posterior column. Parallel to the original plane, sectioned the specimens at 10mm intervals, there were two planes up and down the original plane. Five planes could be obtained （containing anterior column and posterior column of the acetabulum）.The width of posterior column and acetabulum were obtained by analysis of each cross-section. On each cross-section, the safe angulation and length of screw at the point of 10,20mm medial to the margin of acetabular were measured. The results were recorded by x^-±s. Results The width of the acetabulum of middle plane was the widest and the average width was （20.7±1.5）mm. But the width of the acetabulum posterior column of middle plane was the narrowest. The average width was （33.9±2.5）mm . The average minimum angulation of screw for 10mm, 20mm points medial to the acetabular brim at various cross-section were （52.3±5.5）° and （81.4±5.0）° respectively; the average minimum length of screw for 10mm,20 mm points medial to the acetabular brim at various cross-section ware （28.9±2.7） mm and （35.9±4.1） mm respectively.Conclusion The screws can be safely placed into the posterior column of the acetabulum at 10,20mm points medial to the acetabular brim with the anguluation not bigger than 50° and 80° respectivelyand the length no more than 28mm and 35mm respectively.