Smucker Joseph D, Bobst John A, Petersen Emily B, Nepola James V, Fredericks Douglas C
Iowa Spine Research Center, Bone Healing Research Laboratory, Department of Orthopaedics and Rehabilitation, The University of Iowa, USA.
Spine (Phila Pa 1976). 2008 May 20;33(12):1324-9. doi: 10.1097/BRS.0b013e3181732a74.
Six groups of 10 animals underwent single level, uninstrumented posterolateral lumbar fusions. Graft sites were implanted with autologous bone, autologous bone plus B2A coated granules with concentrations of 0-, 50-, 100-, or 300 microg/mL, or no graft material. Explanted motion segments were analyzed by Faxitron radiographs, computerized tomography (CT), manual palpation, and histology.
The synthetic peptide B2A2-K-NS (B2A) was evaluated as a novel agent for augmenting spinal fusion in a posterolateral, noninstrumented rabbit lumbar spine fusion model.
There have been many efforts to increase the rate of posterolateral spinal fusion while, at the same time minimizing, use of autologous bone with its inherent harvest morbidity.
B2A coated ceramic granules (0-, 50-, 100-, and 300 microg/mL) were mixed 1:1 with autogenous iliac crest bone and implanted. Autogenous bone alone was used as a positive control. Fusion was assessed at 6 weeks via radiographs and manual palpation. These results were confirmed with histology and CT.
Fusion results from palpation and radiographic evaluations were similar. CT and histology confirmed bridging bone across the transverse processes for fused spines. The highest fusion rates were observed in the 100 mug B2A/mL group-89% in comparison to 33% for uncoated granules (0 microg B2A/mL) and 63% for autograft alone. These differences were statistically significant.
All investigated B2A concentrations demonstrated increased fusion rates. Fusion masses resulting from the implantation of 100 mug B2A/mL granules demonstrated new woven bone: fused to the transverse processes, within granule pores, bridging bone across the transverse processes, and bridging residual bone graft and granules. It was concluded that each investigated concentration of B2A coated granules in a 1:1 mixture with autograft increased fusion rates in comparison to controls in this rabbit model.
将六组每组10只动物进行单节段、非内固定的腰椎后外侧融合术。移植部位植入自体骨、自体骨加浓度为0、50、100或300微克/毫升的B2A包被颗粒，或不植入移植材料。对取出的运动节段进行Faxitron射线照相、计算机断层扫描（CT）、手动触诊和组织学分析。
在兔腰椎后外侧非内固定融合模型中，评估合成肽B2A2-K-NS（B2A）作为增强脊柱融合的新型药物。
为提高腰椎后外侧融合率，同时尽量减少自体骨采集带来的固有并发症，人们进行了诸多努力。
将B2A包被的陶瓷颗粒（0、50、100和300微克/毫升）与自体髂嵴骨按1:1混合后植入。仅使用自体骨作为阳性对照。在6周时通过射线照相和手动触诊评估融合情况。这些结果通过组织学和CT得到证实。
触诊和射线照相评估的融合结果相似。CT和组织学证实融合脊柱的横突间有桥接骨。在100微克B2A/毫升组观察到最高融合率——89%，相比之下，未包被颗粒（0微克B2A/毫升）为33%，单纯自体移植为63%。这些差异具有统计学意义。
所有研究的B2A浓度均显示融合率增加。植入100微克B2A/毫升颗粒产生的融合块显示出新的编织骨：与横突融合、在颗粒孔隙内、横突间的桥接骨以及桥接残余骨移植和颗粒。得出结论，在该兔模型中，与对照组相比，每种研究浓度的B2A包被颗粒与自体移植按1:1混合均提高了融合率。
