髌骨骨折不同改良方式张力带钢丝固定的生物力学研究及临床应用

Biomechanical evaluation and clinical application of various forms of modified tension band wiring for the treatment of patellar fracture

目的为临床选择有效的髌骨骨折内固定方式提供实验依据.方法取4具外伤截肢后下肢,保留股四头肌腱、髌骨、髌韧带及关节囊,将股骨、胫骨固定在材料试验机上,维持胫股关节屈曲36°位,通过牵拉肌腱产生张力,用线性运动传感器测定骨折移位,移位3mm为固定失效,测AO张力带钢丝、胥氏张力带钢丝、'8'字张力带钢丝和Magnusson钢丝4种固定法.结果 '8'字张力带钢丝和胥氏张力带钢丝固定效果最好,AO张力带钢丝次之,三者均能承受294N以上牵张力,允许术后早期活动,Magnusson钢丝不能承受294N以上牵张力,固定欠可靠.临床应用'8'字张力带钢丝固定治疗髌骨骨折42例,其中横断骨折36例,粉碎性骨折6例,随访6～26个月,优良率达95.2%.结论克氏针'8'字张力带钢丝固定是治疗髌骨骨折首选方法,其固定效果可靠,疗效高.

ve To provide experimental relevant data of internal fixation method for the effec-tive treatment of patellar fracture Methods Four amputation lower limb specimens were used in the experi-ment study. The tendon of quadriceps femoris,patella,patellar ligament and articular capsule of the four limbs were kept intact. The femur and tibia were fixed in an Instron Materials Testing System,and the tibiofemoral joint was held at 36?of flexion. Tension was applied to the patella through the quadriceps tendon and fracture displacement was measured with linear motion transducers. Displacement of 3mm was considered to represent failure of fixation. AO tension band wiring,Xu's tension band wiring,figure of eight tension band wiring and Magnusson wiring were examined respectively. Results The figure of eight and Xu' s tension band wiring were more effective than AO tension band wiring. All of them could bear tensive force over 294N and may pro-vide sufficient fixation to allow immediate range of motion. Magnusson wiring could bear force less than 294N, which appeared not firm enough. Accordingly, 42 cases of patellar fracture were treated with figure of eight tension band wiring, the excellent and good results was 95.2% at follow-up studies ranged from 6 to 26 months. Conclusion Figure of eight tension band wiring should be selected at first in the treatment of fracture of patella for its effective fixation.