胫骨平台骨折兔模型骨折愈合过程中的生物力学研究

Biomechanical study during the healing process of tibial plateau fractures in rabbits model

目的观察胫骨平台骨折兔模型愈合过程中带钢板螺丝钉固定与去钢板螺丝钉所承受的最大载荷及最大点能量变化。方法采用70只新西兰大白兔,制作胫骨平台骨折模型,术中行钢板螺丝钉内固定骨折的胫骨平台,分别于术后当天,1、2、3、4、6、8周取材胫骨标本,7个时间点各取10只大白兔、共70个兔胫骨标本,在万能力学试验机上进行胫骨内侧髁垂直压缩试验,分别测量带钢板螺丝钉固定及去除钢板螺丝钉后标本所能承受的最大载荷、最大点能量。另取10只健康大白兔的胫骨标本,测量相应数据作为对照组。结果模型组最大载荷及吸收能量术后随时间延长逐渐上升,于3周时达到最大,与对照组比较差异有显著性意义(P<0.05),随后开始逐渐降低,在8周时又降至正常水平。两组测量值的变化趋势一致。结论在胫骨平台骨折兔模型愈合的早期过程中,骨折愈合强度呈由低至高然后逐渐下降的曲线变化,钢板螺丝钉内固定可有效促进胫骨平台骨折的愈合。

Objective To evaluate the biomechanical changes with or without Steel plate screw fixation during the healing process of tibial plateau fractures in rabbits model. Methods A total of 70 New Zealand rabbits were used to establish models of tibial plateau fractures and fixed by Steel plate screws. At selected time points tile same day after operation, 1, 2, 3, 4, 6 and 8 weeks after operation, 10 rabbits model in every point, the tibial specimens were harvested and subjected to biomechanical testing. The maximum load of anti - compression at the medial tibial plateau and the energy to maximum in rabbits model with or without fixing Steel plate screw s were recorded. Intact tibia specimens were measured as control group with 10 normal rabbits. Results The maximum load and the energy to maximum increased with the time increasing and reached the peak at 3 weeks postoperatively compared with control group （ P 〈 0.05 ）, then they gradually reduced, finally recovered to normal levels at 8 weeks. The measured values of the two groups changed similarly. Conclusion In the early healing process of tibial plateau fractures, the strength of fracture healing presented a curve change from low to high and then down , and the Steel plate screw fixation was efficient for healing process of tibial plateau fractures.