培养软骨植入干骺端对胫骨生长影响的实验研究

Experimental study on the effect of cultured cartilages on tibial growth by allograft into metaphyses

目的 :探讨培养软骨植入胫骨干骺端缺损后的组织学改变 ,以及对胫骨生长的影响。方法 :自3周龄兔关节软骨分离软骨细胞 ,经离心管培养 2周形成软骨。于 1 6只 1 2周龄新西兰兔右侧胫骨近端生长板下方 1 .5mm处造成边缘性缺损 ,移植培养软骨。左侧胫骨未作手术为正常对照。分别于术后 6、1 2周进行组织学和X线摄片检查。结果 :6周时胫骨近端生长板变窄 ,其下方 6mm处形成薄层软骨或不规则软骨块 ,缺乏生长板柱状细胞排列结构。大量新骨形成和植入区皮质骨增厚。 1 2周时生长板基本闭合 ,干骺端结构正常 ,无软骨。双下肢X线摄片显示双侧胫骨发育无差异 (P >0 .0 5)。结论 :培养软骨植入干骺端可以维持组织性质 。

Objective To investigate histological changes of cultured cartilages and its influence on tibial growth by allograft into metaphyses. Methods: Chondrocytes were isolated from articular cartilages of 3 week old rabbits and formed cartilages by cultivation in centrifuge tubes for 2 weeks.Cultured cartilages were allografted into peripheral defects of proximal tibiae of 16 New Zealand rabbits aged 12 weeks, which were 1.5mm below growth plates.Left tibiae remained untreated as control.Histological and radiographic examinations were respectively performed at 6,12 weeks after surgery. Results: At 6 weeks after operation, the growth plates of proximal tibiae became narrower.One thin layer of cartilage or irregular cartilaginous block formed in the tibial metaphysis 6mm below growth plates, which lacked cellular columnar organization of normal growth plate.A great deal of new bone formed, and cortical bone became wide on the graft site.At 12weeks, the growth plates of proximal tibiae were nearly closed and metaphyseal structure was normal without cartilages.There was not developmental difference of tibiae between the bilateral limbs according to radiography. Conclusions: Cultured cartilages may keep their histological nature after allograft into metaphyses, but they lack structural characteristic and growth ability of growth plate.