Spondylolisthesis reduction instrumentによる後方経路椎体間固定術を施行した形成不全性脊椎すべり症の1例

Surgical Treatment of Congenital Spondylolisthesis with a Spondylolisthesis Reduction Instrument. Case Report

　形成不全性脊椎すべり症は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，神経損傷や術後偽関節などのため治療に難渋することが多い．症例は31歳の女性で，腰痛および両下肢痛が増悪し受診した．入院時現症は，腰椎単純X線像で第5腰椎形成不全すべり症を認めた．手術所見は，手術は後方より進入し，イメージ下に椎弓根スクリューを挿入した．椎弓および椎間関節まで切除し脊髄モニタリングを併用したうえで，直視下にSRIを使用して慎重にイメージで確認しながら整復操作を行った．整復位となった後に椎体間にcageを挿入して固定した．術前のslip angle 22°，％ slip 75.0％は，術後slip angle 7°，％ slip 33.3％に矯正された．術前の腰痛・両下肢痛は消失した．

　Dysplastic spondylolisthesis is a rare disorder that causes L5 anterior subluxation.　Surgical treatment for this disorder, especially in severe cases, is still controversial.　Case：A 31-year-old female was admitted to our department complaining of severe low back pain and bilateral buttock pains and was diagnosed with high-grade dysplastic spondylolisthesis.　Posterior decompression and resection of the sacral dome, reduction of L5 over the sacrum, with a spondylolisthesis reduction instrument and posterior interbody fusion with instrumentation were performed at L5/S1.　The slip angle was corrected from 22 degrees to 7 degrees.　Percentage slip was corrected from 75.0% to 33.3%.　The postoperative course was uneventful.　All of the patient's complaints resolved.