摘要
目的采用三维有限元法分析骨水泥注入量对椎体后凸成形术(PKP)后患椎相邻椎体生物力学的影响。方法经PKP治疗的骨质疏松性椎体压缩性骨折(OVCF)患者69例,根据骨水泥注入量分为低剂量(>2.0 m L且<3.0 m L)组(22例)、中剂量(≥3.0 m L且<6.0 m L)组(28例)、高剂量(≥6 m L)组(19例),采用视觉模拟量表(VAS)评分评价术前、术后的疼痛程度。收集患者手术前后的CT数据,利用Mimics 10.01和Abaqus 6.8软件建立三维有限元模型,在患椎的上终板分别施加0.3 MPa(低压力)、1.0 MPa(中压力)、4.0 MPa(高压力)的轴向压力,观察不同载荷下的应力改变。结果所有患者术后VAS评分与术前相比均明显降低,差异有统计学意义(P<0.05);3组患者术后VAS评分差异无统计学意义(P>0.05)。骨水泥渗漏5例(7.25%),均未出现神经症状;低剂量组1例,中剂量组2例,高剂量组2例,3组间差异无统计学意义(P>0.05)。末次随访未发现相邻椎体再发骨折。在低压力(中立位)时,患椎下位椎体的应力较术前增加约22%,上位椎体的应力增加约15%。在中压力(正常活动)、高压力(突然摔倒)时,高剂量组患椎上、下位椎体的应力较低压力时均明显增加,差异有统计学意义(P<0.05),而中剂量组和低剂量组的患椎上、下位椎体的应力与低压力时相比,差异无统计学意义(P>0.05)。结论 PKP术后可引起患椎上、下相邻节段生物力学的改变,相邻椎体所受的应力随着轴向负荷和骨水泥注入量的增加呈增加趋势。
Objective To explore the biomechanical effects of different amount of bone cement on adjacent vertebral bodies after percutaneous kyphoplasty(PKP). Methods Totally 69 patients with osteoporotic vertebral compression fractures(OVCF) who underwent PKP were included and divided into 3 groups according to the amount of bone cement :low dose(>2.0 m L and <3.0 m L) group(n=22),medium dose( ≥ 3.0 m L and <6.0 m L) group(n=28),and high dose( ≥ 6 m L) group( n=19). The outcome was evaluated by visual analogue scale(VAS) score. The three-dimensional finite element models of 69 patients were built based on CT scan data by the Mimics 10.01 and Abaqus 6.8 software. Different axial pressures(0.3,1.0,and 4.0 MPa) were put on the superior endplate,and the stress on the adjacent vertebrae was analyzed. Results All patients had a decrease in VAS score post-operation compared to pre-operation,with a significant difference(P < 0.05). There was no significant difference in postoperative VAS score between the 3 groups(P > 0.05).Bone cement leak occurred in 5 patients(7.25%),and none of them had neurological symptoms;1 cases in the low dose group,2 cases in the medium dose group and 2 cases in the high dose group,and difference between the 3 groups was not statistically significant(P > 0.05). No adjacent vertebral body fracture was found in the final follow-up. At low pressure(neutral position),the pressure in the lower vertebra increased by about 22% compared with pre-operation;and upper vertebral body stress increased by about 15%. At medium pressure(normal activities) and high pressure(suddenly falls down),stress of the vertebral body in high dose group were significantly increased than neutral position with a statistical difference(P < 0.05),while those in low and medium dose groups showed no difference compared with that at neutral pressure(P > 0.05). Conclusion PKP changes the biomechanical distribution on adjacent vertebrae. With the increases of axial pressure and the amount of bone cement,the biomechanical effect has the increasing trend.
出处
《脊柱外科杂志》
2017年第3期177-181,共5页
Journal of Spinal Surgery
关键词
胸椎
腰椎
骨折
压缩性
骨质疏松
经皮椎体后凸成形术
Thoracic vertebrae
Lumbar vertebrae
Fractures,compression
Osteoporosis
Percutaneous kyphoplasty
