新しい胸椎再建手術：経椎間孔進入胸椎椎体間固定術Transforaminal Thoracic Interbody Fusion（TTIF）

A New Surgical Technique. Transforaminal Thoracic Interbody Fusion (TTIF) and Clinical Outcomes

　経椎間孔進入椎体間固定術は，後方から片側の椎間関節を切除しforaminal zoneからアプローチするため，硬膜管外縁と神経根を直視下に確認でき，除圧に対する有効性は高い．硬膜の牽引を必要としないため神経合併症が少ない．また後方のみでの椎間板操作と椎体間骨移植により前方支柱再建が可能である．今回われわれは，腰椎でのtransforaminal interbody lumbar fusion(TLIF)を応用し，胸椎病変に対しtransforaminal thoracic interbody fusion(TTIF)を施行し，良好な治療成績を得た．今回の検討から本術式は，後方除圧固定と片側性の前方除圧，そして椎体間固定による強固な再建が可能であり，また術後早期離床も可能で骨癒合も良好であった．今後胸椎の除圧再建術の有用な選択肢となりうると考える．

　The purpose of this study was to describe a new surgical technique for use in the thoracic spine i.e., transforaminal thoracic interbody fusion (TTIF), and to evaluate the results of surgery in which it was used.　Ten patients with thoracic lesions associated with neurological deficits were the subjects of this study.　They consisted of 6 men and 4 women, and their mean age was 53 years old.　The thoracic lesions included thoracic disc hernia, spinal trauma, spinal tumor, and arachnoid cyst.　We investigated complications and clinical outcome factors, including operation time, blood loss, and sagittal alignment.　Fusion was judged on the basis of plain and functional radiographs and CT scans.　There were 4 fusions of Th11/12, 3 of Th12/L1, and one each of Th10/11, Th7-9, and Th9-11.　Mean operation time was 192 minutes, and mean intraoperative blood loss was 588ml.　The mean follow-up period was 16 months.　Local alignment was 12.9 degrees of kyphosis preoperatively, and 7.0 degrees postoperatively.　Fusion at the fixed level was observed in every case.　There were no serious complications, such as infection or neural deficit.　All patients were ambulated within 2 days after surgery.　TTIF is a useful reconstructive procedure for thoracic lesions.