I generally described herein, the embodiment of a bone fixation system including a coupling element having a seat PROBLEM TO BE SOLVED]. It is also possible to claim and describes a other embodiments. [Selection Figure] Figure 1C【課題】座を有する連結要素を含む骨固定システムの実施形態を、ここに一般的に記載する。他の実施形態を記載し且つ請求してもよい。【選択図】図1C