在体阻断软骨下营养对关节软骨影响的实验研究

背景：关节软骨无血管分布,其营养来自关节液和软骨下骨,哪条营养通路对关节软骨更为重要是学者们争论的焦点。目的：研究软骨下营养对关节软骨的影响,并探讨软骨下营养与骨关节炎的关系。方法：45只5个月龄雄性新西兰大白兔,建立股骨滑车骨软骨缺损的动物模型,并随机分为3组：自体骨软骨块移植组（Control组,n=15）;假手术组（Sham组,n=15）,用环钻在股骨滑车钻取骨软骨块,将其置入管状PVC内,原位回植;阻断软骨下营养组（DNBM组,n=15）,取出骨软骨后,将其置入帽状PVC内,原位回植。术后4周、8周、12周,每组5只（10膝）,取出膝关节进行大体评分、组织学评分、软骨厚度测量、凋亡染色（TUNEL染色）。结果：与Control组相比,大体评分结果提示,DNBM组软骨无明显退变;组织学评分结果提示,术后12周时DNBM组软骨明显退变（P〈0.005）;软骨厚度测量结果提示,术后8周、12周时DNBM组软骨厚度明显变小（P=0.00）;TUNEL染色结果提示,术后8周、12周时DNBM组关节软骨细胞凋亡明显增加（P〈0.01）。结论：软骨下营养是软骨的重要营养来源,失去软骨下营养,软骨会逐渐发生退变。

Effects of blockade of nutrition deriving from BM on articular cartilage:an experimental study

Background:Articular cartilage is avascular.It is nourished by two potential pathways:blood vessels within subchondral bone and synovial fluid.The importance of these pathways is controversial.Objective:To explore the effect of subchondral bone marrow(BM) as nutrition on articular cartilage in autologous transplants and its relation to the development of osteoarthritis(OA).Methods:Totally 45 5-month-old male New Zealand rabbits were randomly divided into control group(autograft was placed into vascularized,viable cancellous bone well),Sham group(in an identical bone well,autograft was coated with PVC tube),and DNSF group(in an identical bone well,autograft was coated with PVC cat).Nutrition to 4-mm-diameter cylindrical osteochondral plugs created on the trochlea of the distal femurs was obstructed by polyvinyl chloride cap.Knee joints of five rabbits in each group were taken out after 4,8,and 12 weeks.Cartilage changes were assessed by histology,immunohistochemistry,and TUNEL.Results:Cartilage in DNBM group suffered more damage compared with control group 12 weeks after operation(P < 0.005).Cartilage was significantly thinner in DNBM group than that in control group 8 and 12 weeks after operation(P= 0.00).Apoptosis was significantly increased in DNBM group compared with control group 8 and 12 weeks after operation(P < 0.01).Conclusions:BM-derived nutrition is the important nutrition source for adult cartilage structure and function.Interruption of contact between articular cartilage and vascularized subchondral bone will result in cartilage degeneration.