局所骨とチタン製椎体間ケージ，pedicle screwを併用した後方進入腰椎椎体間固定術（PLIF）のX線学的検討

Radiological Assessment of PLIF Using Local Bone in Augmentation with a Titanium Interbody Cage and Pedicle Screw

　切除した椎弓部の局所骨とチタン製椎体間ケージを用いた後方進入腰椎椎体間固定術（PLIF）の骨癒合とX線学的所見の検討を行った．症例は男性9例，女性12例で，手術時年齢は平均62歳，固定椎間数は28椎間であった．術後経過観察は平均2年（1.0～3.5）であった．全体の骨癒合率は89.3％（25/28椎間）であった．Pedicle screwのlooseningは6.5％に認めたが，チタン製椎体間ケージのbackoutを示す症例はなかった．％Slipでは術前17.7±7.5％であったものが，術後3.7±6.1％と有意に改善していた．Slip angleも術前5.9±5.6°であったものが，術後-2.9±4.3°と有意に改善していた（p＜0.01）．Non-unionやcorrection lossを認めた症例はなかった．

　Bony fusion and the radiographic findings after PLIF with the resected lamina and titanium interbody cage for augmention with a pedicle screw were evaluated. The patients consisted of 9 men and 12 women, and their mean age at the time of surgery was 62 years. Twenty-eight segments were the subject of the analysis in this study. The mean follow-up period was 2.0 years. The fusion rate was 89.3％ (25/28 segments). No cage backout was observed, although loosening of the pedicle screw was detected in 6.5％. The mean ％slip changed from 17.7±7.5％ to 3.7±6.1％ postoperatively, and the mean slip angle changed from 5.9±5.6°to-2.6±4.3° (both p＜0.01). No non-union or correction loss has been not observed in any of the patients.