Schwab Frank, Patel Ashish, Lafage Virginie, Farcy Jean-Pierre
New York University Hospital for Joint Diseases, New York, NY, USA.
Spine (Phila Pa 1976). 2009 May 15;34(11):E397-404. doi: 10.1097/BRS.0b013e3181a27156.
An IACUC-approved study to create a scoliotic deformity representative of adolescent idiopathic scoliosis.
The goal of this study was to develop a reliable porcine scoliosis model and to evaluate the three-dimensional progression of the deformity.
Optimal development of nonfusion techniques for treatment of adolescent idiopathic scoliosis requires a reliable large animal model that achieves a progressive three-dimensional (frontal, sagittal, axial) deformity. Limitations in previous work have led our team to the development of a porcine model.
This IACUC-approved study included 18 Yorkshire pigs, obtained at 11 weeks old. Scoliosis was induced through unilateral posterior ligament tethering of the spine via pedicle screw fixation, and ipsilateral ribcage tethering. Progressive deformity was documented with biweekly radiographs. Frontal, sagittal, and axial modifications were assessed using the Cobb method. Animals were observed until severe deformity (>50 degrees) developed, then killed.
Animals were observed for a mean 11 weeks. The mean coronal Cobb angle was 25 degrees immediately postoperatively and 55 degrees at 11 weeks. The mean lordosis increased from 4 degrees postoperative to 24 degrees at final follow-up. Apical axial rotation (posterior elements into concavity) increased from 4% postoperative to 27% at 11 weeks. Rate of coronal curve progression was significantly correlated with the initial Cobb index.
This study establishes a porcine scoliosis model. With placement of a unilateral ligamentous spinal tether combined with concave ribcage ligament tethering a three-dimensional (frontal, sagittal, and axial) spinal deformity can be obtained. The speed of the progressive deformity leaves significant remaining skeletal growth to assess growth modulating therapies for correction. This work forms the basis for a number of investigative efforts at developing new fusionless therapies for patients suffering from adolescent scoliosis.
一项经机构动物护理和使用委员会（IACUC）批准的研究，旨在创建一种代表青少年特发性脊柱侧凸的脊柱侧凸畸形。
本研究的目标是建立一个可靠的猪脊柱侧凸模型，并评估畸形的三维进展情况。
青少年特发性脊柱侧凸非融合治疗技术的优化发展需要一个可靠的大型动物模型，该模型能产生渐进性的三维（额状面、矢状面、轴面）畸形。以往研究的局限性促使我们的团队开发了一种猪模型。
这项经IACUC批准的研究纳入了18只11周龄的约克夏猪。通过椎弓根螺钉固定进行脊柱单侧后韧带束缚以及同侧胸廓束缚来诱导脊柱侧凸。每两周进行X线摄影记录畸形的进展情况。使用Cobb法评估额状面、矢状面和轴面的改变。观察动物直至出现严重畸形（>50度），然后处死。
动物平均观察了11周。术后即刻平均冠状面Cobb角为25度，11周时为55度。平均腰椎前凸从术后的4度增加到最终随访时的24度。顶椎轴旋转（后方结构进入凹侧）从术后的4%增加到11周时的27%。冠状面曲线进展速率与初始Cobb指数显著相关。
本研究建立了一种猪脊柱侧凸模型。通过单侧脊柱韧带束缚联合凹侧胸廓韧带束缚可获得三维（额状面、矢状面和轴面）脊柱畸形。渐进性畸形的速度为评估生长调节治疗以进行矫正留下了大量剩余骨骼生长可供研究。这项工作为开发针对青少年脊柱侧凸患者的新型非融合治疗方法的多项研究奠定了基础。
