颈椎间盘纤维环组织的成骨潜能

背景：椎间盘组织的骨化机制及脊柱韧带、纤维组织的骨化演变过程尚不清楚。目的：实验拟观察颈椎间盘纤维环组织在骨融合过程巾的成骨潜能。设计、时间及地点：对比观察，于2006—10在解放军第二军医大学实验动物中心和上海市伤骨科研究所充成。材料：健康实验山羊10只，雄性6只，雌性4只。羊用钛合金颈椎空心螺纹式柱状内固定器由常州康辉医疗器械有限公司参照羊的颈椎仿人用钛合金颈椎空心螺纹式柱状内固定器定制。方法：实验山羊按常规颈椎前路减压、内固定施术，随机取颈2-6椎间隙中相邻的2个间隙，每个间隙各置入2枚钛合金颈椎空心螺纹式柱状内固定器，共4枚。3枚钛合金颈椎空心螺纹式柱状内固定器中的填充组织分别为：单纯松质骨，松质骨＋纤维环，纤维环。1枚不充填任何组织作为空白对照。主要观察指标：术后6，12周分别拍摄山羊颈椎正侧位X射线平片、颈椎CT平扫观察植入物在位及融合情况。组织学观察各组植骨融合情况及局部组织反应。结果：①X射线平片及CT显示实验山羊内植钛合金颈椎空心螺纹式柱状内固定器在整个实验过程中均在位，无松动、移位、脱落。山羊内植钛合金颈椎空心螺纹式柱状内固定器与椎体的骨-金属界面周围有骨组织生长，与椎体终板接触部位有成骨现象，骨桥形成。②单纯松质骨组新生软骨、骨小梁存在，原植入骨坏死；松质骨＋纤维环组纤维组织有坏死、原骨小梁、纤维环周围新生骨存在，新生软骨堆积；纤维环组术后6周纤维组织内有纤维软骨存在，12周新生软骨存在；空白组对照组术后6周组织学观察无阳性染色结果，12周有少量新生软骨。结论：颈椎间盘纤维环组织的成骨形式可能是成纤维细胞的软骨化骨生成。

Osteogenic potential of fibrous ring tissue in cervical intervertebral disc

BACKGROUND: Ossification of intervertebral disc, and ossification of spinal ligament and fibrous tissues are still uncertain.OBJECTIVE: To observe osteogenic potential of fibrous ring in the cervical intervertebral disc during bone fusion.DESIGN, TIME AND SETTING: The comparative observation was performed at the Experimental Animal Center of Second Military Medical University and Shanghai Institute of Orthopedics in October 2006.MATERIALS: Ten healthy goats, including 6 males and 4 females; titanium alloy cervical hollow threaded columnar internal fixator (CHTF) for goat, simulated human used internal fixator by Kanghui Medical Innovation Co., Ltd., Changzhou.METHODS: Every goat underwent conventional anterior cervical decompression and internal fixation. Two adjacent intervertebral spaces among C2-6 were selected and implanted with 2 CHTFs for each space. Of the 4 CHTFs, 3 were filled with cancellous bone alone, cancellous bone plus fibrous ring, and fibrous ring alone, respectively; the other one filled with nothing served as blank control.MAIN OUTCOME MEASURES: Implant location and fusion condition on anteroposterior and lateral radiographs and CT plain scanning at 6 and 12 weeks postoperatively; bone graft fusion and regional tissue reaction by histology.RESULTS: Radiographs and CT showed that CHTF was in the position during the whole experimental procedure with no loosening, displacement or dislocation. At 6 weeks, bone tissue was found surrounding CHTF and the vertebral body, and bone bridge formed in the connection site of CHTF and the vertebral body. New cartilage and bone trabecula formation were found in the CHTF filled with cancellous bone alone, accompanied by necrotic original bone graft; in the CHTF filled with cancellous bone and fibrous ring, necrotic fibrous tissue and newly formed cartilage accumulation surrounding original bone trabecula and fibrous ring were found; 6 weeks after surgery, there were fibrocartilage in fibrous tissue of CHTF filled with fibrous ring alone, and at 12 weeks postoperatively, newly formed cartilage was observed. In blank control group, only few newly formed cartilages were found at 12 weeks postoperatively. CONCLUSION: Enchondral ossification of fibroblast may be the osteogenic pattern of fibrous ring of cervical intervertebral disc.