PROBLEM TO BE SOLVED: To provide a stem for an artificial hip joint with the structure that a neck is prevented from being tilted relative to a stem body, that fine movements are prevented from arising in the area where the neck is fitted with the stem body and that the neck is changeable.SOLUTION: The stem for an artificial hip joint (a stem 1) includes a stem body 2 to be buried into thighbone and a neck 3 fitted in a concavity 5 formed on the top end of the stem body 2. The end of the neck 3 is provided with a fitting part 4 which includes a fitting part 4b that is in parallel with its opposite surface in addition to a tapered fitting part 4a. Similarly, the concavity 5 of stem body 2 (the fitted part) is made to be the one which includes a fitted part 5b that is in parallel with its opposite surface in addition to a tapered fitted part 5a.COPYRIGHT: (C)2012,JPO&INPIT【課題】ステム本体部材に対してネック部材が傾くことを防止でき、かつネック部材とステム本体部材との嵌合部間に生じる微動を防止できる構造を備えた、ネック部を変更可能な人工股関節用ステムを提供すること。【解決手段】大腿骨に埋入されるステム本体部材2と、ステム本体部材2の上端部に形成された凹部5に嵌合されるネック部材3と、を具備してなる人工股関節用ステム(ステム1)である。対向する面が平行な平行嵌合部4bをテーパ嵌合部4aとは別に有する嵌合部4をネック部材3の端部に設けている。同様に、ステム本体部材2の凹部5(被嵌合部)を、対向する面が平行な平行被嵌合部5bをテーパ被嵌合部5aとは別に有する凹部としている。【選択図】図2
