Patent ID: 7931681

Claim:
An implant system, comprising: an implant attachable to a bony structure, said implant including a hole having a wall surface extending about a central axis, said wall surface being concavely curved between upper and lower surfaces of said implant; a retaining mechanism including a cylindrical body extending between first and second ends and a bore through said body, said body including an outer surface convexly curved between said first and second ends, said retaining mechanism further including an inner wall surface about said bore having a thread profile formed therein with said thread profile extending in said inner surface in a direction from said first end toward said second end of said cylindrical body; and a fastener positionable through said bore of said retaining mechanism, said fastener including an externally threaded shaft threadingly engaging said thread profile in said inner wall surface of said retaining mechanism as said threaded shaft passes through said bore of said retaining mechanism, said fastener including a non-threaded head at a proximal end of said shaft positioned in contact with said inner wall surface to expand said cylindrical body against said wall surface about said hole, wherein said head defines a first width at an outer surface thereof that contacts said inner wall surface of and to expand said cylindrical body of said retaining mechanism and said threaded shaft defines a second width greater than said first width, wherein said second width is a major diameter of said threads and said first width of said outer surface of said non-threaded head contacts said inner surface on said thread profile of said retaining mechanism to expand said cylindrical body into contact with said wall surface of said implant about said hole.