Patent ID: 7048738

Claim:
The method of affixing a bone flap to an adjacent cranial zone, that includes a) providing upper and lower caps between which portions of the cranial bone and bone flap are to be gripped, b) providing a mounting post located to allow relative cap movement lengthwise of an axis defined by the post, c) providing protruding structure on at least the upper cap to extend into a gap formed between the cranial bone and the bone flap to laterally orient the upper cap so that peripheral portions thereof will extend over both the cranial bone and the bone flap during fixation, d) relatively displacing the caps toward one another so that said protruding structure orients the caps as aforesaid, and to engage one of said caps with at least the bone flap or the adjacent cranial bone, and to conformingly retain the caps to opposite sides of the flap and the cranial zone, and e) tightening the caps toward one another into a position wherein relative separation of the caps is blocked, and post extent between the caps is tensioned, f) said protruding structure having a thin frusto-conical side wall tapering toward and adapted to penetrate gaps of different widths between said bone flap and proximate cranial bone, said thin tapering side wall locally engaging edges of said bone flap and of said cranial bone, and there being a thin annular lower wall of the protruding structure integral with said tapering side wall and projecting toward the post to form a central opening for passing the post, and there also being at least three tabs confined at and proximate said central opening, said tabs having narrowed flexure zones integral with said lower wall and heads spaced about the post and extending proximate the post and angled toward an interior void bounded by said tapering side wall, for interfering engagement with serrations on the post, as the cap is tightened axially along the post, said tabs everywhere confined below the upper half of said void.