AF钉复位固定治疗胸腰椎爆裂性骨折

目的　评价AF椎弓根螺钉内固定系统治疗胸腰椎骨折的效果 ,探讨保留棘上韧带半环槽式减压符合生物力学和解剖学特性。方法　C臂X光机透视下按Weinstein解剖定位法拧入螺钉后固定。调整螺栓撑开角度。有全瘫者或CT示有大的骨块突入椎管压迫硬膜囊见椎管变窄大于 30 %者采用保留棘上韧带半环槽式开窗减压。结果　 17例患者椎体前缘高度由术前 55%恢复至术后 85% ,Cobb′s角由术前平均 19 4°恢复至术后 8 9°。椎管内移位骨块复位率达 93 5%。平均随诊 18 2月 ,恢复按ASIA分级 :A级中 2例 ,有 1例无变化 ,余 15例均提高 1～ 3级。结论　AF钉能达到精确复位固定及椎管有效减压 ,应用方便有效。棘上韧带保留半环槽式减压符合生物力学和解剖学特点。

Treatment of Thoraco-lumbar Blow-out Fracture with AF Screw Fixation

Objective To assess the effect of treatment of thoraco-lumbar blow-out fracture with AF screw fixation at arch root and discuss characteristics of groovy decompression at supraspinal ligament remained with hemi-circle. Methods The fixation was done according to Weinstein′s method under fluorometry and adjusted the screw angle. The groovy decompression at supraspinal ligament remained with hemi-circle was underwent when paralysis or large bone protruding into vertebral canal to depress the epidural sac or narrowed more than 30% with CT detection. Results The height of anterior edge of vertebral body recovered from 55% at pre-operation to 85% at post operation. The Cobb's angle recovered from 19.4° at pre-operation to 8.9° at post operation in average. The dislocated bone pieces reached reposition at 93.5% after 18.2 months follow-up in average. 2 cases were in A degree and one unchanged. The other cases increased to 1～3 degree according to ASIA classification.Conclusion AF screw fixation could reach the exact reposition and convenient for application with good effect. The groovy decompression at supraspinal ligament remained with hemi-circle could be accordant with biomechanics and anatomy.