Rail extension for finger joint, has incomplete circle segment whose center point lies on joint axis of finger joint, and cable receiving device provided in such manner that traction force between rail end and finger loop is deflected

摘要

The extension has an incomplete circle segment whose center point lies on a joint axis of a finger joint. A receiving device for receiving a Bowden cable is provided at the extension in such a manner that traction force (Fa) between a proximal rail end and a finger loop is deflected from the extension. Radius of the circle segment is proportional to length of an affected finger phalanx or greater than half of length of the affected finger phalanx. The extension is rotatably mounted on two sides of the concerned joint.