PROBLEM TO BE SOLVED: To solve a problem in which only one instrument can be inserted in the lumen for work of a spine percutaneous endoscope in the cervical spine herniated disk resection under the percutaneous endoscope of back entry, and therefore a herniated disk cannot be resected safely by avoiding nerves.SOLUTION: An inner retractor instrument of this invention has a diameter slightly smaller than the lumen for work, is a cylinder capable of being inserted therein, and is capable of inserting forceps into the lumen of the inner retractor instrument, in which the tip end is shaped in a thin spatula of 1/4 of a circle. Operation is made possible by two pieces of a retractor and the forceps in a little safety area in the cervical spine spinal canal, and thereby surgery can be performed safely.SELECTED DRAWING: Figure 7COPYRIGHT: (C)2020,JPO&INPIT【課題】後方進入の経皮的内視鏡下頸椎椎間板ヘルニア切除術において脊椎経皮的内視鏡の作業用内腔には一本の器具しか挿入できないことから神経をよけて安全に椎間板ヘルニアを摘出することができなかった。【解決手段】当発明の内レトラクター器具は作業用内腔よりわずかに小径でそこに挿入可能な円筒で，内レトラクター器具の内腔に鉗子を挿入でき，その先端部は４分の１円の細いヘラ状になっている．頸椎脊柱管内のわずかな安全領域にてレトラクターと鉗子の二本による操作を可能として手術を安全に行うことが可能となる．【選択図】図７
