C2棘突起付着筋を温存したアプローチによる上位頚椎後方固定術

Posterior Upper-cervical Instrumentation and Fusion with Preservation of the Deep Extensor Muscles Inserting on the C2 Spinous Process

　われわれは軸椎棘突起に付着する頚半棘筋と多裂筋を温存した上位頚椎後方固定術を施行し，良好な成績を得ることができたので報告する．対象は，関節リウマチによる上位頚椎病変に対して手術適応のあった5例である．白石の筋温存型軸椎後方アプローチを用いて軸椎棘突起へ付着する深層伸筋群を確実に同定した後，頚半棘筋と多裂筋を完全に温存した状態で，C2椎弓根スクリューによる後頭環軸椎後方固定を施行した．全例で症状は改善し，特記すべき術後合併症は生じなかった．

　【Purpose】Since 2000, we have been performing instrumentation surgeries by a less invasive exposure technique with preservation of important extensor muscles inserting on the C2 spinous process. The purpose of this paper is to describe the usefulness of this technique for upper-cervical RA lesion. 【Subjects】Five RA patients underwent posterior upper-cervical instrumentation using this exposure technique. 【Surgical technique】The nuchal fascia is divided in line with the skin incision. After identifying the deep extensor muscles in-serting on the C2 spinous process, the entry points of C2 pedicle screws can be exposed by shunting the semispinalis cervicis and multifidus, whose attachments are maintained absolutely intact. 【Result】All patients experienced an improvement in symptoms, and there were no postoperative complications, such as axial pain or limitation of the range of neck motions. 【Conclusion】This new and less invasive surgical technique enabled the placement of C2 (and/or C3) pedicle screws with little difficulty.