The present invention inter-alia relates to an apparatus comprising a receiving opening configured to receive a connecting part of a medical device in a spread condition of the receiving opening and to block receiving the connecting part of the medical device in a relaxed condition of the receiving opening, and a spreader configured to spread the receiving opening in the spread condition such that an opening diameter of the receiving opening is at least as big as an outer diameter of the connecting part of the medical device.本発明はとりわけ、受入開口部の展開状態において医療デバイスの連結部材を受けるように、そして受入開口部の弛緩状態において医療デバイスの連結部材を受けるのをブロックするように構成される受入開口部(300)、及び受入開口部の開口径が医療デバイスの連結部材の外径と少なくとも同じくらいの大きさであるように、展開状態において受入開口部を展開するように構成されるスプレッダ(500)を含んでなる器具に関する。
