中国骨质疏松杂志

不同骨密度对胸腰椎椎弓根内固定早期稳定性的生物力学研究

The biomechanical study of the effect of different bone mineral density on the stability of pedicle screw fixation

DOI：10.3969/j.issn.1006.7108.2016.01.007

英文关键词:Spine osteoporosis Pedicle screw Fixation Stability

基金项目:

作者	单位
王春生1 苏峰2* 张春玲2 宗治国2 王燕波2 张志敏3	1.河北北方学院研究生学院,河北张家口 075000 2.河北北方学院附属第一医院脊柱外科，河北张家口 075000 3.河北北方学院附属第一医院放射科

摘要点击次数: 851

全文下载次数: 760

中文摘要:

目的研究不同骨密度对椎弓根螺钉内固定早期稳定性的影响，为临床工作提供生物力学参考。方法取新鲜成年绵羊胸腰椎脊柱标本（T13-L2)36具,采用随机数字表法分为4组，分别为A(HCl脱钙0 h)、B(HCl脱钙2 h)、C( HCl脱钙4 h)、D(HCl脱钙6h)组，每组9个。采用EXPERT-XL双能X线骨密度仪（Lunar公司）对四组脊柱椎体进行测量,依据骨密度的不同分为骨量正常组、骨量减少组、骨质疏松组、严重骨质疏松组。4组均采用在T14-L2上置入椎弓根钉棒系统。以（300 ± 105)N的载荷对4组模型进行250 000次循环4个方向（前屈、后伸、左侧弯、右侧弯）加载，比较4组模型的脊柱活动范围、螺钉的最大拔出力、轴向压缩刚度。结果疲劳试验后，A、B、C、D组脊柱的运动范围值（ROM)、轴向压缩刚度依次增大、螺钉的最大拔出依次减小，各组间差异有统计学意义（P <0.05〉。结论1.脊柱骨密度越低，椎弓根固定后脊柱早期的稳定性越差。2.对于骨密度在骨质疏松范围内的患者不能行单纯椎弓根螺钉固定，而且在骨性愈合期间应减少脊柱的活动量。

英文摘要:

Objective To explore the effect of different bone mineral density (BMD) on the stability of pedicle screws fixation, and to provide biomechanical basis for the clinical work. Methods A total of 36 fresh thoracic and lumbar vertebra samples of adult sheep (T13-L3) were equally divided into 4 groups，A (decalcified with HCl for 0h)，B (decalcified with HCl for 2 h), C (decalcified with HCl for 4 h), and D (decalcified with HCl for 6 h) by using the random number table method. Nine samples in each group. BMD of the thoracic and lumbar spine was measured using dual energy X-ray absorptiometry (DXA). According to BMD, the samples were divided into normal bone mass group, osteopenia group, osteoporosis group, and serious osteoporosis group. Four screws were applied in the T14-L2 pedicle of vertebral arch in all the 4 groups. Fatigue test of 250 000 times in 4 directions (flexion, extension, left lateral bending, and right lateral bending) with 300±105 N load was performed. The range of motion (ROM), the maximal drawing force of the screws, and the axial compressive stiffness were measured and the differences among the groups were compared. Results After fatigue test, ROM and drawing force in turn in A, B, C, and D group, and screw pullout decreased in turn in those groups. The differences among the groups were statistically significant (P < 0. 05). Conclusion 1) The lower the BMD of spine is, the worse the pedicle screw fixation stability is in the early phase. 2) The patients with osteoporosis can not use pedicle screw fixation only. And before bone healing, they should reduce spinal activity.

查看全文查看/发表评论下载PDF阅读器

关闭