EXTENSION DEVICE FOR BONE ANCHOR, SYSTEM FOR EXTENSION DEVICE AND SPINE STABILIZATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an extension device for a bone anchor.SOLUTION: An extension device includes a first sleeve (1) that has a first sleeve axis coaxial with a central axis. The first sleeve (1) is configured so as to be coupled with a receiving part of a bone anchor and to be uncoupled from the receiving part. The extension device also includes a second sleeve (2) that has a second sleeve axis coaxial with the central axis. The second sleeve (2) is positioned within the first sleeve (1) and can be positioned along the central axis with respect to the first sleeve. The second sleeve (2) is also configured so as to be coupled with the receiving part and to be uncoupled from the receiving part. Furthermore, the extension device in the first configuration includes a locking member (35) that prohibits one of the first sleeve (1) and the second sleeve (2) from being uncoupled from the receiving part when the other of the first sleeve (1) and the second sleeve (2) remains coupled with the receiving part.