Abstract: Minimally invasive methods and devices for introducing a spinal fixation element into a surgical site in a patient's spinal column are provided. In general, the method involves advancing a spinal fixation element in a first, lengthwise orientation along a pathway extending from a minimally invasive percutaneous incision to a spinal anchor site. As the spinal fixation element approaches the spinal anchor site, the fixation element can be manipulated to extend in a second orientation, which is preferably substantially transverse to the first orientation, to position the fixation element in relation to one or more spinal anchors.

Abstract: An assembly such as an anchor screw, bone plate, offset hook, post, transverse connector or other spinal anchor for anchoring to bone and clamping a linkage such as a rod, wire cable or the like. The assembly has a top member with an open slot to receive the linkage, and a twist-lock closure cap to close the open end, capturing the linkage in the slot. One closure cap fits over and around the top member, with a set of segmented protrusions that extend through a corresponding set of protruding flange segments spaced about the circumference of the top member. The cap is configured to rotate and lock against the top member like a flange-locking bayonet mount when turned through a limited degree of rotation.