兔胫骨骨延长模型在低强度脉冲超声刺激条件下的骨再生与成熟

背景:实验证实,低强度脉冲超声有促进骨折愈合的作用.但低强度脉冲超声对骨折愈合早期骨质再生成熟的影响及其相关的作用机制仍不十分清楚.目的;创新性提出低强度脉冲超声能够在兔胫骨骨延长动物模型牵拉成骨早期骨再生成熟中发挥正效效应的理论假设,并期望以超声干预与不干预进行对照比较予以验证. 方法:36只成年健康新西兰兔随机数字表法分为超声治疗组和对照组,每组18只.所有动物均行胫骨中段截骨,以Orthofix M103型迷你外固定架延长器固定,术后7 d以0.5 mm/12 h延长10 d,总延长长度为10 mm,超声治疗组在延长完成后以低强度脉冲超声骨折治疗仪治疗,20 min/d,1次/d,对照组不给予低强度脉冲超声治疗.治疗4,8,12周后,X射线评定胫骨骨折断端愈合程度,采用Image J图像分析软件分析计算骨痂生成率;延长区新骨作苏木精-伊红染色、Masson三色染色、VG染色后光镜下组织学分析,并在显微镜下测新骨占总骨痂的面积.结果与结论:36只兔均进入结果分析.治疗4周后对照组仅见外骨痂连接形成骨桥,骨痂区密度低,还可见部分骨痂缺如:超声治疗组骨早期再生成熟优于对照组,表现在两断端骨痂影密度增高,数量增多,骨痂影由两端向中央生长,被密度高的骨痂取代,外骨痂已开始被吸收,骨痂充满延长区,密度增高增粗,骨折处皮质骨密度接近正常皮质骨,骨痂生成率明显提高(P＜0.05),与8,12周无差异.组织学分析显示,超声治疗组治疗4,8,12周时新骨形成早于对照组,治疗4周新骨占总骨痂面积的百分比大于对照组,治疗8,12周后两组新骨占总骨痂面积的百分比无差别.提示低强度脉冲超声可促进新骨形成,增加骨痂面积,在兔胫骨骨延长动物模型牵拉成骨后的骨再生成熟中有促进作用.

Bone regeneration and maturation in a rabbit tibia lengthening model under low-intensity purse ultrasound stimulation

BACKGROUND: Experiments has demonstrated that low-intensity pulse ultrasound stimulations (LIPUS) can accelerate bone healing. However, its affect mechanisms on maturation of regenerated bone remain unclear. OBJECTIVE: The hypothesis that LIPUS has positive effect on maturation of regenerate bone was put forward creatively, and wants to verify the hypothesis by compare the difference between LIPUS intervention and no intervention. METHODS: Thirty-six adult, healthy, New Zealand White rabbits were randomly a...