臨床整形外科53巻8号

2018年08月発行

誌上シンポジウム 椎弓形成術 アップデート

頚椎後縦靱帯骨化症に対する術式選択の指標：K-line

著者： 國府田正雄¹ 古矢丈雄² 牧聡² 飯島靖² 齊藤淳哉² 北村充広² 宮本卓弥² 安部哲哉¹ 船山徹¹ 野口裕史¹ 三浦紘世¹ 長島克弥¹ 熊谷洋¹ 俣木健太朗¹ 柴尾洋介¹ 大鳥精司² 山崎正志¹

所属機関： ¹筑波大学医学医療系整形外科学 ²千葉大学大学院医学研究院整形外科学

ページ範囲：P.661 - P.667

　頚椎後縦靱帯骨化症(ossification of the posterior longitudinal ligament：OPLL)の術式選択の参考になる指標として，K-lineがある．頚椎単純X線立位側面像中間位でC2およびC7脊柱管前後径の中点を結んだ線をK-lineとし，骨化巣の頂点がK-lineを越えないものをK-line(＋)，骨化巣の頂点がK-line上にある・越えるものをK-line(−)と定義する．K-line(＋)の症例は椎弓形成術単独で十分な脊髄除圧が期待しうるが，K-line(−)症例では椎弓形成術単独では除圧不足に陥る可能性が高いため，前方除圧固定術または後方除圧固定術を選択する．

　K-lineは動きの要素を反映していないこと・計測困難例などK-lineの弱点および対処法を理解したうえで用いれば，K-lineは頚椎OPLLに対する術式選択に際して非常に有用である．

参考文献

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10) Ijima Y, Furuya T, Ota M, et al. The K-line in the cervical ossification of the posterior longitudinal ligament is different on plain radiographs and CT images. J Spinal Surgery (in press).