富血小板血浆促进牵拉成骨矿化过程的放射学评估

目的探讨富血小板血浆(PRP)对牵拉成骨矿化过程的影响。方法将20只健康新西兰大白兔随机分为PRP组和对照组(n=10)。兔左侧胫骨胫腓关节下方截骨1cm短缩后以单臂外固定架进行延长(术后第7天开始,1mm/d,共延长1cm),PRP组在术后第17天和第27天各局部注射PRP500μl,对照组无处理。术后第37天处死动物取材。于手术当天及术后第12、17、27、37天用C形臂动态观察新生骨的矿化过程,取材后拍X线片并行Micro-CT扫描评价新生骨的骨矿物质含量及密度。结果PRP组新生骨的生成情况明显优于对照组。X线结果显示在PRP组的牵张间隙内可见明显连续高密度影,骨痂量明显多于对照组。Micro-CT三维重建图像示PRP组新生骨生长及塑形良好,对照组只有少量皮质连续。PRP组骨矿物质含量(310.8±44.2mg)及骨矿物质密度(228.8±22.3mg/cm3)均明显高于对照组(分别为125.8±25.1mg、86.4±23.8mg/cm3,P<0.05)。结论在兔胫骨缺损延长动物模型中,PRP局部注射可显著促进牵拉成骨矿化过程中新生骨的矿化。

Radiographic evaluation of the effect that local injection of platelet-rich plasma enhances bone consolidation

Objective In this study, we tested the ability of platelet-rich plasma to enhance bone consolidation during distraction osteogenesis in a rabbit model of leg lengthening. Methods Twenty New Zealand white rabbits, which were randomly divided into two groups, the PRP treated group and the control group (n=10). Osteotomy will be made under the tibiofibular junction of left tibia, and 1cm tibia shaft will be removed through a second osteotomy. The tibia will be shorted for 1cm and then fixed by Orthfix unilateral lengthener with 4 pins. Lengthening will start 7 days after the osteotomy surgery, at a rate of 1.0 mm/day, in two steps, for 10 days. 500ul PRP were respectively injected into the distraction gaps at the end of the 10-day lengthening and at 10 days before termination. No management in the control group. The animals were terminated at day 20 following final lengthening. Serial radiographs will be taken at the day of surgery, day 12, day 17, day 27, day 37, using a C-arm radiography system. The excised bone specimens were scanned by X-ray and Micro-CT, and the bone mineral content(BMC) and the bone mineral density(BMD) of the regenerates were calculated and compared. Results The regenerate of PRP treated group was significantly better than the control group. The X-ray figures showed that the regenerate was significantly more than the control group. The figures of micro-CT 3D reconstruction showed that the growth and remodel of the regenerate in PRP treated group was better than the control group. Micro-CT examination of regenerates demonstrated a significantly greater bone mineral content(BMC) and the bone mineral density(BMD) in the PRP treated group compared to the control group(P<0.05). Conclusions This study has demonstrated that local injection of platelet-rich plasma enhanced bone consolidation during distraction osteogenesis in the rabbit model.