経皮的椎弓根スクリューシステムを用いた経椎間孔腰椎椎体間固定術におけるアライメント変化

Realignment by Transforaminal Lumbar Interbody Fusion with a Percutaneous Pedicle Screw System

　X線透視装置のみを併用し，経皮的椎弓根スクリューシステムを用いた経椎間孔腰椎椎体間固定術のアライメント変化について検討した．対象症例は12例で，臨床成績，矢状面アライメント，スクリューの挿入位置，椎間ケージの術後変位について検討した．アライメントは術後有意に改善した．スクリューは椎弓根を逸脱しておらず，椎間ケージの術後変位もなかった．固定椎間のアライメントを改善し，椎間ケージの術後変位を防止するためには十分な椎間開大と多くの骨移植，大きな椎間ケージが必要である．

　To assess sagittal alignment restored by TLIF with a percutaneous pedicle screw system, 12 cases of TLIF with percutaneous pedicle screw system were performed with an image intensifier. All operations were performed by the same surgeon. Operation time, blood loss, complications, sagittal alignment (disc angle and ％PDH) of the fused segment, accuracy of screw placement and translation of intervertebral cages were evaluated. A matched-pair comparison with patients treated by the previous procedure was also carried out. The percutaneous procedure took longer than the previous method. Postoperative sagittal alignment was better in of both groups. There were no malpositioned screws and no cage translation. The results of TLIF with the percutaneous pedicle screw system suggest the efficacy of less muscle invasion and sagittal alignment reconstruction. Sufficient distraction of the intervertebral space, larger cages, and grafting a large amount of bone enable good alignment and prevent cage translation.