Department of Orthopedic Surgery, Kurume University, Fukuoka, Japan.
Department of Orthopedic Surgery, Kurume University, Fukuoka, Japan.
Spine J. 2023 Feb;23(2):325-335. doi: 10.1016/j.spinee.2022.08.019. Epub 2022 Sep 3.
Platelet-rich plasma (PRP) can accelerate bone union in spinal fusion surgery with an autogenous bone graft. However, it is unclear whether bone union can be obtained by using artificial bone and PRP together in spinal interbody fusion surgery.
This study aimed to determine whether interbody fusion can be achieved by transplanting porous hydroxyapatite/collagen(HAp/Col) which is an artificial bone material frequently used in spinal fusion surgery, together with PRP in the intervertebral disc space in rats.
A controlled laboratory study.
A total of fourty 10-week old Sprague-Dawley rats were used in this study and assigned to three groups as follow: disc curettage only (control group, n=10), disc curettage + HAp/Col transplant (H group, n=10), and disc curettage + HAp/Col + PRP transplant (H+P group, n=10). The other 10 rats were sacrificed as blood donors for acquisition of PRP. Microcomputed tomography (μCT) examinations were performed to evaluate bone union, bone volume (BV), and bone mineral density (BMD) at 4, 8, and 12 weeks following surgery. Twelve weeks postoperatively, each group of three of L4-L5 spines was harvested to perform histological examination (hematoxylin & eosin stain) and the others were subjected to biomechanical testing (compression properties).
The platelet count in PRP was approximately 4.1 times greater than that in whole blood (260.6±26.2 × 10 mg/dL and 64.3±2.9 × 10 mg/dL in PRP and whole blood, respectively). All the L4-L5 lumbar discs were fused in the H+P group, whereas only one case was fused in the H group and none in the control group at 12 weeks after surgery. BV was significantly higher in the H+P group than in the H group or control groups (both p<.01), although BMD was not significantly different among the three groups. Upon histological analysis, mature bone formation was observed at the transplanted space in all cases in the H+P group, whereas fibrous tissue was observed at the location in the H and control groups. Regarding biomechanical properties, the ultimate load to failure was significantly higher in the H+P group than in the H group or control group (p=.021 and .013, respectively), although stiffness was not significantly different between the three groups.
The combination of porous HAp/Col and PRP at an appropriate concentration can promote bone union in the intervertebral disc space without using an autologous bone graft in the rat model. Bone tissue formation was histologically confirmed, and it was mechanically strong.
This preclinical study showed that porous HAp/Col, when combined with PRP at an appropriate concentration, can induce bone union without autologous bone grafts. The results may eliminate the need for autologous bone collection for spinal fusion surgery in the future.
富含血小板的血浆（PRP）可加速自体骨移植物在脊柱融合术中的骨愈合。然而，在脊柱椎间融合术中，同时使用人工骨和 PRP 是否能获得骨融合尚不清楚。
本研究旨在确定在大鼠椎间盘空间中移植常用的人工骨材料多孔羟磷灰石/胶原（HAp/Col）与 PRP 是否能实现椎间融合。
对照实验室研究。
本研究共使用 40 只 10 周龄的 Sprague-Dawley 大鼠，分为三组：仅椎间盘切除术（对照组，n=10）、椎间盘切除术+HAp/Col 移植（H 组，n=10）和椎间盘切除术+HAp/Col+PRP 移植（H+P 组，n=10）。另外 10 只大鼠作为 PRP 采集的血供被处死。术后 4、8 和 12 周分别进行微计算机断层扫描（μCT）检查，评估骨融合、骨体积（BV）和骨矿物质密度（BMD）。术后 12 周，每组 3 只 L4-L5 脊柱进行组织学检查（苏木精和伊红染色），其余进行生物力学测试（压缩性能）。
PRP 中的血小板计数约为全血的 4.1 倍（PRP 为 260.6±26.2×10 mg/dL，全血为 64.3±2.9×10 mg/dL）。在 H+P 组，所有的 L4-L5 腰椎间盘均融合，而在 H 组仅 1 例融合，对照组无融合。与 H 组和对照组相比，H+P 组的 BV 显著更高（均<.01），尽管三组间 BMD 无显著差异。组织学分析显示，在 H+P 组的所有移植部位均观察到成熟骨形成，而在 H 组和对照组的移植部位观察到纤维组织。在生物力学性能方面，H+P 组的破坏载荷显著高于 H 组和对照组（分别为 p=.021 和.013），尽管三组间刚度无显著差异。
在大鼠模型中，将多孔 HAp/Col 与适当浓度的 PRP 结合使用，无需自体骨移植即可促进椎间盘空间的骨融合。组织学上证实了骨组织的形成，并且具有较强的机械性能。
这项临床前研究表明，在适当浓度下，多孔 HAp/Col 与 PRP 结合使用可诱导骨融合，无需自体骨移植。研究结果可能会消除未来脊柱融合手术中自体骨采集的需要。
