富含血小板血浆对兔胫骨牵张成骨的影响

The role of platelet - rich plasma for rabbit tibial distraction osteogenesis

目的观察富含血小板血浆（PRP）在新西兰兔胫骨骨折后牵张成骨过程中的作用。方法取50只健康成年的新西兰大耳兔随机分组，建立右侧胫骨骨折后牵张成骨模型。分组：Ⅰ组为非PRP（n＝ 20），Ⅱ组为PRP（n＝ 30）。Ⅰ组分两亚组：ⅠA组（n＝ 10）胫骨中段骨折建模后直接牵张，持续牵张14 d；ⅠB组（n＝ 10）胫骨中段骨折建模后，静息7 d，随后持续牵张14 d。Ⅱ组分为3亚组：ⅡA组（n＝ 10）胫骨中段骨折建模后骨折端注射0.5 ml PRP后直接牵张，持续牵张14 d；ⅡB组（n＝ 10）胫骨中段骨折建模后，静息14 d，注射0.5 ml PRP然后持续牵张14 d；ⅡC组（n＝ 10）胫骨中段骨折建模后，静息7 d，然后持续牵张14 d，牵张结束后注射0.5 ml PRP。各实验组兔分别于牵张后7、14、21、42、70 d动态X线观察评价活体新生骨质矿化。所有兔均于牵张70 d后立即处死，取右小腿制作新鲜标本进行高分辨率Micro-CT扫描（不剥离软组织），扫描对象为胫骨中段14 mm长的新生骨，扫描结束后并以所有新生骨为分析对象，分析新生骨骨矿物质含量（BMC）和骨密度（BMD）。结果Ⅰ、Ⅱ组BMC结果分别为463 913.9±48 089.3，560 688.7±85 044.3，I组较低，差异有统计学意义（t＝2.513，P＝0.026）；Ⅰ、Ⅱ组BMD结果分别为134.2±13.9，162.2±24.7，I组较低，差异有统计学意义（t＝2.504，P＝0.026）。ⅠA、ⅠB组BMC结果分别为455 162.3±51 284.8，472 665.5±54 051.3，差异无统计学意义（t＝0.407，P＝0.705）；ⅠA、ⅠB组BMD结果分别为131.7±14.8，136.8±15.6，差异无统计学意义（t＝0.407，P＝0.705）。ⅡA、ⅡB、ⅡC组BMC结果分别为557 070.0±104 692.6，589 549.9±5 407.5，535 446.3±125 362.6，差异无统计学意义（F＝0.250，P＝0.787）；ⅡA、ⅡB、ⅡC组BMD结果分别为161.2±30.3, 170.5±4.6, 196.7±36.3，差异无统计学意义（F＝0.246，P＝0.789）。结论PRP能够加速成骨过程，提高新生骨BMC和BMD，缩短成骨时间，而注射时间并不重要。

Objective To evaluate the role of platelet rich plasma （PRP） for rabbits tibial distraction osteogenesis.Methods 50 healthy adult New Zealand rabbits were randomly divided into two groups, and then establish the tibial bone fracture distraction osteogenesis models on the right side. Group Ⅰ without used PRP （n= 20）, and group Ⅱ with used PRP （n= 30）. Group Ⅰ were divided into two subgroups, group ⅠA （n= 10） with distraction osteogenesis for 14 d after tibia fracture modeling created. group ⅠB （n= 10） with distraction osteogenesis for 14 d begin at 7 d after tibia fracture modeling created. Group Ⅱ was divided into three subgroups： group ⅡA （n= 10） with distraction osteogenesis for 14 d after tibia fracture modeling created and 0.5 ml PRP was injected on the fracture site. Group ⅡB （n= 10） with distraction osteogenesis for 14 d begin at 14 d after tibia fracture modeling created and 0.5 ml PRP was injected on the fracture site. Group ⅡC （n= 10） with distraction osteogenesis for 14 d begin at 7 d after tibia fracture modeling created, and 0.5 ml PRP was injected on the fracture site after distracted. Evaluation of new bone mineralization by X-ray at the 7, 14, 21, 42, 70 d after distraction osteogenesis. All rabbits were sacrificed immediately at the 70 d after distraction osteogenesis and the fracture site on the right leg were evaluated by bone mineral content （BMC） and bone mineral density （BMD） through Micro-CT scans.Results The value of BMC were 463 913.9±48 089.3, 560 688.7±85 044.3 for group Ⅰ and group Ⅱ, group I was obviously lower than group Ⅱ and the difference was statistically significant （t=2.513, P=0.026）. the value of BMD were 134.2±13.9, 162.2±24.7 for group Ⅰ and group Ⅱ, group Ⅰ was obviously lower than group Ⅱ and the difference was statistically significant （t=2.504, P=0.026）. The value of BMC were 455 162.3±51 284.8, 472 665.5±54 051.3 for group ⅠA and group ⅠB, and the difference was statistically significant （t=0.407, P=0.705）. The value of BMD were 131.7±14.8, 136.8±15.6 for group ⅠA and group ⅠB, and the difference was statistically significant （t=0.407, P=0.705）. The value of BMC were 557 070.0±104 692.6, 589 549.9±5 407.5, 535 446.3±125 362.6 for group ⅡA, ⅡB, ⅡC, and the difference was statistically significant （F=0.250, P=0.787）. The value of BMD were 161.2±30.3, 170.5±4.6, 196.7±36.3 for group ⅡA, ⅡB, ⅡC, and the difference was statistically significant （F=0.246, P=0.789）.Conclusion PRP can accelerate bone formation, increase new bone mineral density and bone mineral content, shorting the time of distraction osteogenesis, and injection time is not important.