山羊颈椎切除减压后行颈前路可调控式融合固定器植骨融合的效果观察

Bone graft fusion in goat model implanted with anterior cervical-adjustable fusion fixator after anterior cervical corpectomy:an observation of outcome

目的观察颈前路可调控式融合固定器(AC-AFF)植骨融合的初步效果,为后续研究奠定基础。方法18只山羊均行颈前路手术减压切除1个颈椎椎体,随机分为3组,分别施以AC-AFF、钢板+钛网、钢板+髂骨块固定融合。饲养6个月后,颈椎标本经固定脱水等处理,依次通过大体观察、X线摄片、CT扫描及显微镜下观察,评价植骨融合情况;同时观察AC-AFF与相邻椎体界面之间的融合情况。结果所有山羊均存活,内固定物牢固在位,无松动及移位,钛网或AC-AFF与相邻骨接触面局部膨大,硬化为骨性。髂骨植骨组融合情况良好,融合界面上有较多的骨痂生成。X线摄片见植骨块、钛网、AC-AFF中空区域模糊且有骨组织生长,内植物周围无透光带存在,植骨界面上有骨桥形成;CT扫描在钛网及AC-AFF组可见内植物腔内形成的新骨通过其四壁的网眼结构与周围骨质相接,说明所有标本均达到骨性融合,但其中以AC-AFF组形成的新骨数量为多,且较为成熟。光镜观察发现在椎体终板及内植物与减压槽侧壁骨质接触处,有纤维细胞及软骨细胞生成,但在钛网植入物的侧壁腔隙局部仍有无骨痂通过区存在。结论AC-AFF植骨融合良好,与植骨块及钛网植骨方式之间无明显差异,植骨界面有纤维细胞及软骨细胞生成,可作为颈椎减压术后稳定性重建的方法之一。

Objective To observe the bone graft fusion of goat cervical model implanted with anterior cervical-adjustable fusion fixator（AC-AFF）,laying a foundation for future studies.Methods Eighteen experiment goats were implanted with AC-AFF,titanium mesh and autogenous iliac bone combined cervical plate after corpectomy.Six months later,the fused cervical spine vertebrae were collected,prepared,and observed grossly,under microscope,by X-ray photographs and CT scan;the fusion of the graft was evaluated.Meanwhile,the fusion of AC-AFF with the adjacent vertebral surface was observed.Results All the experiment animals survived after operation;all the implants were stable,without displace or loosening.The interface where the titanium or AC-AFF contacts the vertebral body surface was bulged and ossified.All iliac bone graft fused well and a great deal of bony callus was found covering the vertebral body surface.Lucency area was not seen surrounding the bone graft,titanium and AC-AFF on the X-ray films,and there was new bone formation in the interface of internal fixation and bone.The central region of titanium and AC-AFF became vague and new bone formation was found in the intracavitary area of implants by CT scan.And part of the new bone transited the parietal reticulation and connected with normal ossea at titanium and AC-AFF.A large number of phoroblasts and chondrocytes were found microscopically in the bone fusion sites in all cases;however,the region without bony callus still existed in the titanium mesh lateral wall.Conclusion There are no differences in bone fusion between AC-AFF with titanium mesh and autogenous iliac bone combined cervical plate.New phoroblasts and chondrocytes can be generated in the bone graft interface.AC-AFF has been proven as an important method for cervical stability reconstruction after decompression operation.