Department of Orthopedic, Beijing Hospital, Beijing, China.
Chin Med J (Engl). 2009 Nov 20;122(22):2770-4.
Biphasic calcium phosphate (BCP) ceramics has a potential advantage as an osteoconductive matrix and has an optimal resorption rate for bone formation. Using BCP ceramics as a bone graft during spinal fusion requires osteogenesis within the material and subsequent bridging between adjacent vertebrae to provide long-term support. Bisphosphonates have been reported to prolong the process of bone healing. The influence of bisphosphonate treatment on bone formation within BCP ceramics in spinal fusion remains unknown. The aim of this study was to evaluate the influence of alendronate on BCP osteogenesis in posterolateral spinal fusion.
Posterolateral spinal fusion with pedicle screw fixation was performed at the lumbar spine in twenty-two pigs. BCP ceramics were applied as a bone graft to obtain bone fusion between adjacent transverse processes. Eleven pigs in the treatment group received oral alendronate 10 mg/d for three months postoperatively. Eleven pigs in the control group did not receive treatment with alendronate. All animals underwent posterolateral spinal fusion with BCP ceramics. The fusion rate was evaluated three months after the operation.
The fusion rates evaluated by X-ray were 27.3% in the treatment group and 20% in the control group. The fusion rates using histological evaluation were 18.2% in the treatment group and 20% in the control group. The mean volumes of fusion mass were (3.64 +/- 0.86) cm(3) in the treatment group and (4.26 +/- 0.63) cm(3) in the control group. No significant differences were found in either trabecular bone volume or residual BCP volume between treatment and control groups using histological evaluation. The new bone formation within BCP ceramics was greater in the area adjacent to transverse process (P < 0.01).
Oral alendronate with a dose of 10 mg daily do not inhibit bone formation within BCP ceramics or affect the fusion rate in posterolateral spinal fusion from porcine models.
双相磷酸钙（BCP）陶瓷具有作为骨传导基质的潜在优势，并且具有最佳的成骨吸收率，可促进骨形成。在脊柱融合过程中使用 BCP 陶瓷作为骨移植物需要在材料内成骨，并随后在相邻椎骨之间桥接，以提供长期支撑。双膦酸盐已被报道可延长骨愈合过程。双膦酸盐治疗对脊柱融合中 BCP 陶瓷内骨形成的影响尚不清楚。本研究旨在评估阿仑膦酸钠对 BCP 在后外侧脊柱融合中的成骨作用。
在 22 头猪的腰椎进行后路脊柱融合，采用经皮椎弓根螺钉固定。将 BCP 陶瓷作为骨移植物应用于相邻横突之间，以获得骨融合。治疗组 11 头猪术后口服阿仑膦酸钠 10mg/d，共 3 个月。对照组 11 头猪未接受阿仑膦酸钠治疗。所有动物均进行 BCP 陶瓷后外侧脊柱融合。术后 3 个月评估融合率。
X 射线评估的融合率在治疗组为 27.3%，在对照组为 20%。组织学评估的融合率在治疗组为 18.2%，在对照组为 20%。治疗组融合质量的平均体积为（3.64±0.86）cm3，对照组为（4.26±0.63）cm3。组织学评估显示，治疗组和对照组之间小梁骨体积或残留 BCP 体积无显著差异。BCP 陶瓷内新骨形成在横突相邻区域更大（P<0.01）。
每日口服 10mg 阿仑膦酸钠不会抑制 BCP 陶瓷内骨形成，也不会影响猪模型后路脊柱融合的融合率。
