PROBLEM TO BE SOLVED: To provide a bone resection tool capable of easily and highly accurately performing additional resection on a resection surface of a bone. A bone cutting instrument (1) has a tip saw blade (12) and vibrates at a high speed to cut a bone with which the tip saw blade (12) contacts, and a substantially flat blade body (10) and a substantially flat tip guide. A guide plate 20 that has a portion 21 and is located on the upper surface side of the blade body 10 and is slidably connected to the blade body 10 in the front-rear direction. A projecting guide position that projects toward the tip side of the saw blade 12 and covers the tip saw blade 12, guides the cutting position in the thickness direction by the tip saw blade 12, and a retracted position where the tip guide part 21 retracts from the tip saw blade 12. And a guide plate 20 that is slidable between and. [Selection diagram] Figure 1【課題】骨の切除面に対して容易且つ高精度に追加の切除を行うことのできる骨切除器具を提供する。【解決手段】骨切除器具１は、先端ノコギリ刃１２を有し、高速振動することで、先端ノコギリ刃１２が接触する骨を切削する略平板状のブレード本体１０と、略平板状の先端ガイド部２１を有し、ブレード本体１０の上面側に位置して、ブレード本体１０と前後方向に相対的にスライド自在に連結されるガイドプレート２０であって、先端ガイド部２１がブレード本体１０の先端ノコギリ刃１２よりも先端側に突出して先端ノコギリ刃１２を覆い、先端ノコギリ刃１２による厚み方向の切削位置を案内する突出ガイド位置と、先端ガイド部２１が先端ノコギリ刃１２よりも後退した後退位置との間でスライド自在なガイドプレート２０と、を備える。【選択図】図１
