Cook S D, Dalton J E, Prewett A B, Whitecloud T S
Department of Orthopaedic Surgery, Tulane School of Medicine, New Orleans, Louisiana, USA.
Spine (Phila Pa 1976). 1995 Apr 15;20(8):877-86. doi: 10.1097/00007632-199504150-00002.
Posterior lumbar spinal fusion segments were evaluated in 9 adult mongrel dogs 6, 12, and 26 weeks after implantation. Four sites on each animal received implants consisting of demineralized bone matrix alone, demineralized bone matrix with allograft bone, allograft bone alone, and autograft bone. Each unilateral fusion spanned one motion segment with one intervening vertebral level left undisturbed using T13-L7. The fusions were evaluated radiographically, mechanically, and histologically.
The purpose of this study was to determine the efficacy of demineralized bone matrix as a bone graft substitute for stable posterior spinal fusion.
Posterior spinal fusion is a procedure commonly performed for spinal stabilization. Increasing the incidence and speed of stable spinal fusion is a primary goal in spinal surgery. Concerns have developed regarding the graft material used to induce bone healing at the fusion site. The advent of osteoinductive materials, such as demineralized bone matrix, may eliminate the need to harvest autograft bone and may circumvent the immunologic response and lower osteogenic potential associated with allograft bone.
The quality of fusion and new bone formation was evaluated radiographically using plain films, computed tomography, and magnetic resonance imaging. After the dogs were killed, each fusion segment was evaluated mechanically in torsion to determine stiffness and histologically to determine qualitative parameters of new bone formation and remodeling.
Radiographic studies showed that autograft bone sites achieved stable fusion by 26 weeks after surgery. Conversely, the demineralized bone matrix alone and with allograft bone demonstrated some new bone formation at 6 and 12 weeks, but did not achieve fusion by 26 weeks. The fusion sites of allograft bone alone showed minimal new bone formation at all time periods. Mechanically, the autograft fusion sites demonstrated torsional stability that was significantly greater than that of all other fusion sites at all time periods. The remaining fusion sites showed equivalent torsional stiffness at all time periods. Histologic analysis confirmed the radiographic and mechanical findings.
The results indicate that demineralized bone matrix alone or with allograft bone is ineffective in achieving stable posterior spinal fusions.
对9只成年杂种犬植入后6周、12周和26周的腰椎后路融合节段进行评估。每只动物的四个部位分别植入仅含脱矿骨基质、含同种异体骨的脱矿骨基质、仅含同种异体骨以及自体骨。每个单侧融合跨越一个运动节段，使用T13 - L7，其中一个中间椎体节段保持不动。对融合情况进行影像学、力学和组织学评估。
本研究的目的是确定脱矿骨基质作为骨移植替代物用于稳定的后路脊柱融合的疗效。
后路脊柱融合是一种常用于脊柱稳定的手术。提高稳定脊柱融合的发生率和速度是脊柱外科的主要目标。人们对用于诱导融合部位骨愈合的移植材料产生了担忧。脱矿骨基质等骨诱导材料的出现，可能无需采集自体骨，并可规避与同种异体骨相关的免疫反应和较低的成骨潜能。
使用X线平片、计算机断层扫描和磁共振成像对融合质量和新骨形成进行影像学评估。犬处死之后，对每个融合节段进行扭转力学评估以确定刚度，并进行组织学评估以确定新骨形成和重塑的定性参数。
影像学研究表明，自体骨部位在术后26周实现了稳定融合。相反，仅含脱矿骨基质以及含同种异体骨的脱矿骨基质在6周和12周时显示出一些新骨形成，但在26周时未实现融合。仅含同种异体骨的融合部位在所有时间段新骨形成均极少。力学方面，自体骨融合部位在所有时间段均表现出显著高于所有其他融合部位的扭转稳定性。其余融合部位在所有时间段显示出相当的扭转刚度。组织学分析证实了影像学和力学研究结果。
结果表明，仅含脱矿骨基质或含同种异体骨的脱矿骨基质在实现稳定的后路脊柱融合方面无效。
