AF内固定治疗胸腰椎爆裂性骨折增强脊柱稳定性的研究

Posterior approach with AF system fixation for thoracolumbar blow-out fracture to increase spinal stability

目的探讨胸腰椎爆裂性骨折后路AF内固定撑开复位、间接减压的疗效。方法对33例患者的治疗进行回顾性分析。患者为胸腰椎爆裂性骨折,但MRI示后纵韧带仍完整。其中24例伴脊髓损伤,按Frankel分级,A级2例、B级7例、C级9例、D级6例。9例无神经压迫症状。治疗均采用后路AF系统撑开复位内固定,结合横突间、椎板间植骨。术前及不同随访时间行CT检查,分别计算其伤椎椎体高度及椎管狭窄率,确定椎体高度及椎管横截面积的恢复程度,采用配对t检验方法进行统计学分析。结果33例术后平均随访13.4个月,伤椎前柱高度、后柱高度、椎管狭窄率治疗前分别为47.9,82.1,(29.3±13.5)%;治疗后分别为86.6(t=3.034,P<0.01),92.3(t=3.401,P<0.01),(7.3±7.9)%(t=3.626,P<0.01)。24例脊髓损伤患者中,神经功能恢复按Frankel分级评定,22例分别提高1～3级,2例A级无变化。33例中有2例AF钉断裂,余患者内固定稳定,未见椎体塌陷。结论AF系统治疗后纵韧带完整的胸腰椎爆裂性骨折,通过撑开复位,间接减压,能有效恢复椎体高度及椎管形态,以维持和增强脊柱稳定性。

Aim To investigate the efficacy of AF device in the treatment of thoracolumbar blow out fracture.Methods Thirty three cases of thoracolumbar blow out fracture with intact posterior longitudinal ligaments were analyzed retrospectively.24 patients whose spinal cord was injured belonged to Frankel grade A(n=2),grade B(n=7),grade C(n=9) and grade D(n=6) respectively,of which 9 patients had not neurological deficit.All cases were operated upon by posterior reduction to get indirect decompression and internal fixation by AF fixation system,combined with intertransverse and interverteral bone grafts.The height and severity of spinal canal stenosis of the injured vertebrae was calculated and recovery degree of the height and transverse area of the vertebral canal was determined respectively according to the CT films obtained before operation and in various time intervals of follow up.Results Thrty three patients were followed up for 13.4 months averagely.The height of anterior column and posterior column of injured vertebral bodies was 47.9 and 82.1 respectively before treatment, significantly lower than that after treatment (86.6 and 92.3,t=3.034 and 3.401,P< 0.01).The rate of spinal stenosis was( 29.3± 13.5) % before treatment,significantly higher than that after treatment [(7.3± 7.9)% ,t=3.626,P< 0.01].For the 24 patients with incomplete spinal cord injury, the Frankel grade improved for 1- 3 grades in 22 patients and did not change in 2 patients of grade A.Except AF screws cracking occurred in 2 cases, there was no collapse of vertebra.Conclusion For thoracolumbar burst fractures with the longitudinal ligaments being intact,AF device has satisfactory effect for reducing the height and spinal canal diameter,to improve indirect decompression and neurological function recovery.<P>