Meissner A, Fell M, Wilk R, Boenick U, Rahmanzadeh R
Klinik für Unfall-, Wiederherstellungs-, Hand- und Plastische Chirurgie, Klinikum Krefeld.
Unfallchirurg. 1998 Jan;101(1):18-25. doi: 10.1007/s001130050227.
For the stabilization of the ruptured pubic symphysis, rigid forms of fixation such as plate osteosynthesis and flexible fixations such as wire loops or PDS banding have been recommended. All methods have only been tested by static unidirectional loading until failure of the system. By this experimental arrangement Ecke and Hofmann found comparable results for flexible and rigid methods of internal stabilization of the pubic symphysis. They preferred flexible methods to maintain mobility of the symphysis and to prevent symphyseal fusion. We tested dynamic compression plate osteosynthesis, reconstruction plate osteosynthesis, wire loops and PDS banding for internal fixation of injured pubic symphysis in a dynamic multidirectional experimental arrangement simulating gait conditions. The specimens were loaded with 85 N in vertical (y-) direction and 34 N in sagittal (z-) direction, which represent 50% of the forces acting at the pubic symphysis during walking and with a frequency of 1.5 Hz over 55,500 loads simulating the conditions over a 6-week mobilization period. Loading with 100% of the acting forces (corresponding to full weight bearing mobilization) led to early failure of the system. Our experimental analysis showed that neither wire loops nor PDS banding is able to stabilize the ruptured pubic symphysis, even immediately after fixation before loading. During the tests instability increased until failure of the system due to cutting of the bone or breaking of the wires or PDS banding. Success of plate osteosynthesis was dependent on the initial stability of the fixation. Overwinding of the screws, as in osteoporotic bone, lead to increasing loosening during repeated loading, whereas primary stable fixation of the screws was almost completely maintained during the test. In consequence, neither wire loops nor PDS banding should be used for stabilization of injured pubic symphysis if early mobilization with partial weight bearing is desired. Plate osteosynthesis (DC or reconstruction plate) tolerates early half weight bearing in patients with "open-book" injury only if safe screw fixation is guaranteed.
对于耻骨联合破裂的稳定，已推荐采用钢板接骨术等刚性固定方式以及钢丝环扎或聚对二氧环己酮（PDS）带扎等柔性固定方式。所有方法仅通过静态单向加载直至系统失效进行了测试。通过这种实验设置，埃克和霍夫曼发现耻骨联合内固定的柔性和刚性方法有可比的结果。他们更倾向于柔性方法以保持耻骨联合的活动度并防止耻骨联合融合。我们在模拟步态条件的动态多向实验设置中测试了动力加压钢板接骨术、重建钢板接骨术、钢丝环扎和PDS带扎用于损伤耻骨联合的内固定。标本在垂直（y轴）方向承受85 N的力，在矢状（z轴）方向承受34 N的力，这代表步行时作用于耻骨联合的力的50%，并以1.5 Hz的频率加载超过55,500次，模拟6周活动期的情况。以100%的作用力加载（相当于完全负重活动）会导致系统早期失效。我们的实验分析表明，即使在加载前刚固定后，钢丝环扎和PDS带扎都无法稳定破裂的耻骨联合。在测试过程中，由于骨质切割或钢丝或PDS带扎断裂，不稳定性增加直至系统失效。钢板接骨术的成功取决于固定的初始稳定性。如在骨质疏松性骨中那样螺钉过度拧紧会导致在反复加载过程中松动增加，而螺钉的初次稳定固定在测试过程中几乎完全得以维持。因此，如果希望早期部分负重活动，钢丝环扎和PDS带扎都不应被用于损伤耻骨联合的稳定。仅在确保螺钉安全固定的情况下，钢板接骨术（动力加压或重建钢板）才耐受“书本型”损伤患者的早期半负重。
