伤后不同时期髓内固定对骨折愈合影响的实验研究

摘要

目的 探讨伤后不同时期髓内固定对兔胫骨骨折愈合过程的影响.方法 清洁剂兔行右侧胫骨中段横形截骨后,随机分为即时固定组(A组)、延迟1周固定组(B组)和延迟2周固定组(C组),均行克氏针(Φ＝2.5mm)髓内固定术,术后行X线、组织学及BMP -2免疫组化观察.结果 术后1、4周时B、C组和A组间差异有统计学意义(P＜0.05),B组和C组相比则差异无统计学意义(P＞0.05)；术后2周时3组间差异均有统计学意义(P＜0.05).结论 实验性骨折在一定的时间内延迟切开复位内固定可加速骨折愈合.%Objective To detect the effect of early versus delayed internal fixation on fracture healing. Methods Rabbits with transverse osteotomy of middle diaphyses of right tibial were divided randomly into three groups: group A (immediate internal fixation on the day of injury) ,group B( delayed internal fixation at the end of the first week) and group C( delayed internal fixation at the end of the second week). All fractures were immobilized with a 2. 5mm - diameter kirsehner wire as intramedullary nail. The X - ray films,histologi-cal and immunohistochemical sections were made for the evaluation of effects on fracture healing after internal fixation. Results There was a significant difference between group B or C and A( P < 0. 05 ) , not a significant difference between group B and C ( P > 0. 05 ) at 1,4 weeks after internal fixation. There was a significant difference among group A, B and C ( P < 0. 05) at 2 weeks after internal fixation. Conclusion It is beneficial to the healing of fracture that open reduction and internal fixation of the closed tibial fracture is delayed in a limited time.