Removable medical implant closure for open headed implants
OwnerRoger P. Jacksoninventor
Life of this patent
Estimating the term…
Abstract
A closure for use in conjunction with an open headed medical implant for capturing and locking a rod member in the implant comprises a radially outward threaded cylindrical body sized and shaped to be threadably received between two arms of a head of the implant. The closure also includes a driving head and a coaxial removal head. The driving head breaks away from the body at a predetermined torque leaving the removal head. The driving head and removal head are of sufficiently dissimilar shape to prevent a tool with a socket for gripping the driving head from inadvertently gripping the removal head during installation and over-torquing the closure.
Claims13
A closure for use in conjunction with a medical implant that is sized and shaped to operably close a channel between two spaced arms with each of said arms having an inward threaded surface;
- said closure comprising:
- a) a body having an axis of rotation and a threaded cylindrical shaped radially outward surface with threads sized and shaped to be threadably mated with the threaded surfaces of the implant arms;
- b) a break-off driving head having a first external cross section associated therewith perpendicular to the axis of rotation;
- said driving head having a radially outward driving surface that is polyhedral in shape and adapted to receive a driving tool for torquing said closure;
- said driving head being adapted to rotate and torque said body in said implant until a preselected torque occurs at which time said break-off head breaks from said body;
- and
- c) a removal head having a polyhedral shape with radially outward facing engagement surfaces adapted to engage a removal tool;
- said removal head being located initially between said threaded cylindrical shaped radially outward surface of said body and said driving head;
- said removal head having a second external cross section associated therewith perpendicular to the axis of rotation with said second cross section being different from said first cross section and being adapted to receive a removal tool for removal of said closure;
- said removal head outward facing surfaces being sized and shaped so as to not receive and be driven by a driving tool engaging said driving head;
- and said removal head second external cross section being different in size and share from an external cross section of said body and having no threads thereon.
A medical implant system comprising:
- a) an open headed medical implant having a head formed by a pair of spaced interiorly threaded arms defining a channel therebetween sized and shaped to receive a rod member;
- and;
- b) a closure member including:
- i) a body having an axis of rotation and a threaded cylindrical shaped radially outward surface with threads sized and shaped to be threadably mated with said threaded arms;
- ii) a driving head having an external polyhedral shaped torquing surface adapted to be gripped by a torquing tool and having a first cross section associated therewith perpendicular to the axis of rotation;
- said driving head operably allowing a user to rotate and torque said body with the torquing tool until a preselected torque occurs whereat said driving head breaks from said body;
- and
- iii) a removal head located between said body and said driving head;
- said removal head having a radially outward facing removal surface sized and shaped to engage a removal tool and being free of external threads;
- said removal head having a second cross section associated therewith perpendicular to the axis of rotation with said second cross section being different in comparison to said driving head first cross section and sized and shaped to not receive the torquing tool, so that during torquing of said driving head, said removal head is also not inadvertently driven by the torquing tool;
- said removal head second cross section also being externally different than a third cross section associated with said body.
A closure for use in conjunction with an open headed medical implant having a pair of interiorly threaded arms forming a channel therebetween for receiving the closure;
- said closure closing said channel upon being received between said arms;
- said closure comprising:
- a) a cylindrical shaped body with a radial outward threaded surface sized and shaped to be threadably received between the arms of the implant;
- said body having an axis of rotation;
- b) a driving head axially aligned with and initially attached to said body and having a first gripable polyhedral shaped outer surface;
- said driving head operably rotating and torquing said body and breaking from said body at a preselected torque;
- and
- c) a removal head axially aligned with and attached to said body and located between said body and said driving head for removing said body from the implant;
- said removal head being free of external threads;
- said removal head being located external of said body and between said body and said driving head;
- said removal head having a second gripable radially outward facing outer surface;
- said first and second gripable outer surface being different in configuration so as to prevent a tool used with said first surface from also accidentally gripping said second surface during torquing of said driving head;
- said removal head having an external cross section that is different from said cylindrical body.
Dependencies are inferred from the claim text.