Receiving part for receiving a rod for coupling the rod to a bone anchoring element and a bone anchoring device with such a receiving part

摘要

A receiving part for coupling a rod to a bone anchoring element includes a receiving part body including a rod receiving portion having a channel for receiving a rod, and a head receiving portion for accommodating a head of a bone anchoring element, the head receiving portion having an open end and being flexible for inserting and clamping of the head; and a locking ring around the head receiving portion, wherein in a pre-locking position, a spring portion on one of the locking ring or the receiving part body engages a corresponding portion on the other one of the locking ring or the receiving part body, and the locking ring exerts a first force onto the head receiving portion, and wherein in a locking position, the locking ring exerts a second force greater than the first force onto the head receiving portion to lock the head therein.

主权项

1. A receiving part for receiving a rod for coupling the rod to a bone anchoring element, the receiving part comprising:
a receiving part body comprising a rod receiving portion having a channel for receiving a rod, and a head receiving portion for accommodating a head of a bone anchoring element, the head receiving portion having an open end and being flexible for inserting and clamping of the head; and a locking ring configured to be positioned around the head receiving portion, the locking ring comprising a spring portion, wherein the spring portion is configured to engage the receiving part body to hold the locking ring at an insertion position where the head receiving portion is radially expandable, and where the receiving part body urges the spring portion radially outward to define a first outer width of the locking ring, wherein the spring portion is further configured to engage the receiving part body to hold the locking ring at a pre-locking position where the locking ring restricts radial expansion of the head receiving portion, and where the spring portion defines a second outer width of the locking ring that is smaller than the first outer width, and wherein the locking ring is further configured to assume a locking position where the locking ring exerts a force onto the head receiving portion to lock the head of the bone anchoring element therein.