Hamasaki Takahiko, Tanaka Nobuhiro, Kim JinHwan, Okada Motohiro, Ochi Mitsuo, Hutton William C
Department of Orthopaedic Surgery, Emory Spine Center, Atlanta, GA 30329, USA.
J Spinal Disord Tech. 2010 Apr;23(2):127-32. doi: 10.1097/BSD.0b013e31819942cd.
Biomechanical study using human thoracolumbar spines.
To assess the strength of fixation of pedicle screws augmented with Nesplon tape applied sublaminar or applied subpars.
There are no reports on the biomechanical assessment of Nesplon tape used for pedicle screw augmentation.
Experiment 1: pedicle screws were inserted into bilateral pedicles as follows: (1) pedicle screw alone connected to a rod (PS alone), (2) pedicle screw augmented with Nesplon tape applied sublaminar, connected to a rod [pedicle screw applied sublaminar (PSSL)], and (3) pedicle screw augmented with tape applied subpars, connected to a rod [pedicle screw applied subpars (PSSP)]. The rods were pulled and pushed until the pedicle screw was loose. Experiment 2: 6 thoracolumbar spines were biomechanically tested as follows: axial compression, flexion, extension, left and right lateral bending, and left and right axial rotation. This sequence was applied to: (1) the intact spine; (2) the spine made unstable; (3) the spine fixed by pedicle screws and rods (PS alone); (4) the same as 3, but with the pedicle screws augmented using Nesplon tape applied sublaminar (PSSL); and (5) the same as 3, but with pedicle screws augmented using tape applied subpars (PSSP). From the load-deformation curves, stiffness values were calculated.
Experiment 1: the pedicle screws augmented by sublaminar or subpars tape (PSSL or PSSP) showed significantly greater fixation strength compared with those pedicles that were not augmented by tape (PS alone). Experiment 2: a pedicle screw/rod construct augmented by tape provided a stiffer construct than the same construct without augmentation.
Pedicle screws that are inserted into the osteoporotic thoracolumbar spine and augmented by Nesplon tape applied sublaminar or subpars provide firmer fixation of the screws and a stiffer pedicle screw/rod construct than the same construct without augmentation by tape.
使用人体胸腰椎进行生物力学研究。
评估通过在椎板下或椎弓根峡部下应用Nesplon带增强的椎弓根螺钉的固定强度。
尚无关于用于增强椎弓根螺钉的Nesplon带的生物力学评估的报道。
实验1:将椎弓根螺钉插入双侧椎弓根,如下所示:(1)仅将椎弓根螺钉连接至棒(仅PS);(2)在椎板下应用Nesplon带增强的椎弓根螺钉,连接至棒[椎板下应用椎弓根螺钉(PSSL)];(3)在椎弓根峡部下应用带增强的椎弓根螺钉,连接至棒[椎弓根峡部下应用椎弓根螺钉(PSSP)]。拉动并推动棒,直至椎弓根螺钉松动。实验2:对6个胸腰椎进行如下生物力学测试:轴向压缩、前屈、后伸、左右侧屈以及左右轴向旋转。该序列应用于:(1)完整脊柱;(2)造成不稳定的脊柱;(3)用椎弓根螺钉和棒固定的脊柱(仅PS);(4)与(3)相同,但椎弓根螺钉使用在椎板下应用的Nesplon带进行增强(PSSL);(5)与(3)相同,但椎弓根螺钉使用在椎弓根峡部下应用的带进行增强(PSSP)。根据载荷-变形曲线计算刚度值。
实验1:与未用带增强的椎弓根(仅PS)相比,用椎板下或椎弓根峡部下带(PSSL或PSSP)增强的椎弓根螺钉显示出显著更高的固定强度。实验2:用带增强的椎弓根螺钉/棒结构比未增强的相同结构提供了更硬的结构。
插入骨质疏松性胸腰椎并通过在椎板下或椎弓根峡部下应用Nesplon带增强的椎弓根螺钉,比未用带增强的相同结构能提供更牢固的螺钉固定以及更硬的椎弓根螺钉/棒结构。