锁定重建接骨板治疗髋臼横行伴后壁骨折的生物力学研究

Biomechanical Study of Acetabunlum Transverse and Posterior Wall Fractures Treated by Internal Fixation with Locking Reconstruction Plate

目的研究髋臼横行伴后壁骨折3种方式内固定的稳定性。方法 9个完整骨盆的18个髋臼标本根据随机数字法分为3组,建立髋臼横行伴后壁骨折模型,行3种方式内固定:A组:后柱重建接骨板结合后壁2枚拉力螺钉固定;B组:后柱锁定重建接骨板固定;C组:后柱重建接骨板结合后壁2枚拉力螺钉、前柱半螺纹松质骨拉力螺钉固定。于单足站立中立位进行轴向加载,观察3组能承担的最大负载和加载至2 200 N时后壁骨折块的位移。结果A、B、C组能承担的最大负载分别为(2 243.74±116.36)N、(2 769.05±131.42)N及(2 832.87±137.93)N,三组在加载至2 200 N时后壁骨折块的位移分别为(2.15±0.26)mm、(0.45±0.05)mm及(0.53±0.07)mm。B、C两组差异无统计学意义(P>0.05)。B、C两组数据与A组比较,差异均有统计学意义(P<0.05,P<0.01)。结论锁定重建接骨板固定髋臼横行伴后壁骨折固定可靠,能够满足患者早期功能锻炼的要求,具有较大临床应用价值。

Objective To evaluate the stability of 3 different internal fixation methods for transverse and posterior wall fractures of the acetabulum. Methods Seighteen acetabula of 9 whole pelvises were divided into 3 groups randomly. Models of transverse and posterior wall fraeturesof aeetabulum were established and then fixed with one of following three internal fixation methods： （ Group A ） posterior column locking reconstruction plate group, （ Group B ） posterior column common reconstruction plate withposterior wall 2 lag screwsgroup , （ Group C） anterior column lag screw and posterior column common reconstruction plate with posterior wall2 lag screws group, biomechanical tests are conducted in a single leg stance tomeasurethe maximal loads in the three groups and the displacements of the posterior wall fractures when the stress were loaded to 2 200 N on the three groups. Results The maximal loads in Groups A,B,C were as follows： （2243.74 ± 116.36） N,（2769.05 ± 131.42） N, （2832.87 ± 137.93 ） N. When the stress was loaded to 2 200 N on the three groupS, the displacements of the posterior wall fractures were as foUows：（2.15±0.26） ram, （0.45±0.05） mm, （0.53 ±0. 07） ram. We found there was no significant difference between the Group B and the Group C （ P 〉 0.05 ）. There was significant difference between Groups B, C and Groups A, （ P 〈 O. 05,P 〈 0.01 ）. Conclusion For the acetabular transverse and posterior wall fractures, locking reconstruction plate internal fixation methods can provide sufficient stability to satisfy the requirements of physical training at early stage, which gives great clinical values.