Transforaminal lumbar interbody fusionによる整復固定術を施行した形成不全性第5腰椎すべり症の1例

L5 Dysplastic Lumbar Spondylolisthesis Corrected by Transforaminal Lumbar Interbody Fusion. Case Report

　形成不全性脊椎すべり症は第5腰椎の椎弓や上位仙椎の形成不全により腰仙関節前方亜脱臼を来す稀な疾患であるが，術中神経損傷や術後偽関節などのため術式は確立されていない．今回，形成不全性第5腰椎すべり症に対しtransforaminal interbody fusionを応用した椎体間固定術を施行し，slip angle 35°→25°，％slip 29％→5％と改善した．本法は椎体間操作時の神経損傷の可能性が低い点と両側L5神経根を除圧できる点から，形成不全性脊椎すべり症に対して有効な手術法と思われる．

　Dysplastic spondylolisthesis is a rare disorder that induces L5 anterior subluxation. Although surgical treatment for this disease, especially in the severe cases, needs intervertebral fixation, reduction or both, it has not been established because of the intra-operative nerve injury or post-operative pseudoarthrosis. We report a case of a 19-year-old woman with L5 dysplastic spondylolisthesis who underwent reduction-fixation using transforaminal lumbar interbody fusion. Her slip angle and ％slip improved from 35° to 25° and from 29％ to 5％ respectively. This procedure is useful for dysplastic spondylolisthesis in the points of both a low risk of nerve injury and decompression of the bilateral L5 neural foramens.