Cobb角40°以上の胸腰椎・腰椎変性後側弯症に対する矯正固定術における新しいアンカー（sacral-alar-iliac fixation）

Evaluation of a New Spino-pelvic Fixation (Sacral-alar-iliac Fixation) Technique for Severe Degenerative Thoracolumbar Kyphoscoliosis

　背景：仙椎から仙腸関節を貫通させ遠位部を腸骨とする新しいスクリュー固定方法(sacral-alar-iliac fixation：以下，SAIF)が成人脊柱変形例に対する後方矯正固定手術において有用であるかを検討した．

　対象と方法：Cobb角40°以上の胸腰椎・腰椎変性後側弯症6例を対象とした．術前後の臨床成績，骨癒合，矯正率を検討した．

　結果：JOAスコアは術前11.3点，最終診察時21点(改善率54.9%)であった．全例，腰仙椎間の骨癒合が得られ，皮膚トラブルはなかった．Cobb角の矯正率は68.1％で良好であった．

　まとめ：SAIFは重度脊柱変形に対する矯正固定術における有用な遠位部アンカーである．

　Background：Sacral-alar-iliac fixation (SAIF) has recently been reported as a new lumbosacral fixation Technique in which screws are inserted into the sacral ala and then used to penetrate the sacroiliac joint until they are anchored in the ilium.　This method has the advantage of having a lower implant profile, technique, and it can provide good surgical outcomes in corrective surgery for spinal deformities.

　Methods：We evaluated the clinical outcome, lumbosacral joint fusion rate, and correction rate in six patients with degenerative thoracolumbar and lumbar kyphoscoliosis whose Cobb's angle was more than 40 degrees.

　Results：CT images of all patients showed bony fusion of the lumbosacral joint, and no surgical wound complications developed.　The JOA score improved from 11.3 points before surgery to 21 points at the final follow-up examination.　The JOA score improvement rate was 54.9%, and the Cobb's angle correction rate was 68.1%.

　Conclusion：SAIF is a useful anchoring technique for lumbosacral fixation in corrective surgery for adult spinal deformities.