Anti-splay medical implant closure with central multi-surface insertion and removal aperture
OwnerRoger P. Jacksoninventor
Life of this patent
Estimating the term…
Abstract
An anti-splay closure with a multi-surfaced aperture, such as a multi-lobular socket, includes a cylindrical body with an external, continuous, helically extending anti-splay guide and advancement flange. The multi-lobular socket includes a plurality of circumferentially spaced lobes extending parallel to a closure axis of the plug and which circumferentially alternate with spline receiving grooves extending parallel to the closure axis. The closure is used with an open headed bone implant screw having arms that are provided with internal, helically extending mating guide and advancement structures complementary to the body flange to allow slidable mating with the body upon rotation thereof and radial interlocking between the arms and the body.
Claims20
A closure for setting engagement with a structural member and comprising:
- (a) a substantially cylindrical body having an outer cylindrical surface relative to a central closure axis;
- (b) a substantially continuous guide and advancement flange extending helically about said outer cylindrical surface, said flange having a leading surface and a trailing surface relative to a direction of forward advancement;
- (c) at least one of said leading surface or said trailing surface being compound in contour and including an inward facing anti-splay surface component facing generally toward said closure axis;
- and
- (d) said body having a multi-surface aperture formed therein that is aligned with said closure axis and that is elongated along said closure axis, said aperture opening onto a trailing surface of said body and including a plurality of circumferentially spaced, centrally facing surfaces extending substantially parallel to said closure axis that are aligned to form a removal socket adapted to receive a removal tool.
The closure and bone implant screw combination as set forth in claim 6 wherein:
- (a) said mating guide and advancement structures of said bone implant screw include an outward anti-splay surface component which cooperates with said inward anti-splay surface component of said closure in such a manner as to resist a tendency of said arms to splay in reaction to torquing said closure into engagement with said bone fixation structural member.
A closure for setting engagement with a structural member and comprising:
- (a) a substantially cylindrical body having an outer cylindrical surface relative to a central closure axis;
- (b) a guide and advancement flange extending helically about said outer cylindrical surface, said flange having a trailing surface relative to said forward advancement direction;
- (c) said trailing surface being compound in contour and including an inward facing anti-splay surface component facing generally toward said closure axis;
- and
- (d) said body having a multi-lobular aperture formed therein which is aligned on and elongated along said closure axis, said aperture including a plurality of circumferentially spaced lobes extending substantially parallel to said closure axis and said lobes circumferentially alternating with bore grooves extending substantially parallel to said closure axis to form a removal socket adapted to receive a removal tool.
A closure for setting engagement with a structural member and including a substantially cylindrical body having an outer cylindrical surface relative to a central closure axis and a substantially continuous guide and advancement flange extending helically about said outer cylindrical surface, said flange having a leading surface and a trailing surface relative to a direction of forward advancement, the improvement comprising:
- (a) at least one of said leading surface and said trailing surface being compound in contour and including an inward facing anti-splay surface component facing generally toward said closure axis;
- and
- (b) said body having a multi-surfaced aperture formed therein which is located and elongated along said closure axis, said aperture including a plurality of circumferentially spaced surfaces extending substantially parallel to said closure axis so as to form a removal socket adapted to receive a removal tool.
Dependencies are inferred from the claim text.