Patent ID: 8632574

Claim:
A bone plate kit for use in stabilizing a fracture of a bone, comprising: a) a bone plate having an upper surface, a bone contacting lower surface, and a plurality of a screw holes extending between the upper and lower surfaces, said plurality of screw holes including, i) a tapered locking screw hole having threads helically arranged about its interior, the locking screw hole having an upper opening with an upper diameter, and a lower opening with a lower diameter, and ii) a compression screw hole having an upper opening with a first diameter, and a lower opening with a second diameter smaller than said first diameter in one direction and a third diameter equal to said first diameter in a direction orthogonal to the second diameter, and defining a central axis through the centers of the upper and lower openings, at least one rail extending across a portion of said compression screw hole to define a screw seat with an angled upper surface, and a vertical wall with a thickness extending in the same dimension as a central axis of said compression screw hole; and b) a plurality of bone screws, each having a head and a shaft, said head including conically tapered external threads, a proximal peripheral rim, a driver engagement socket at a proximal end of said screw head for receiving a torque driver tool, and a lower bearing annulus distal of said external threads, said bearing annulus smaller in diameter than said external threads and defined by a conical surface, and said shaft including bone engaging threads defining a shaft major diameter, a shaft minor diameter, and a shaft thread pitch, wherein, said shaft thread pitch is approximate to, but greater than, said thickness of said vertical wall of said compression screw hole, said shaft major diameter is larger than said second diameter of said compression screw hole, and said shaft minor diameter is smaller than said second diameter of said compression screw hole, wherein, a first of said bone screws can be inserted into said tapered locking screw hole, with said shaft extending through said lower opening of said locking screw hole and said tapered threads of said head of said screw engaging said internal threads of said locking screw hole to engage said screw relative to said plate, and a second of said bone screws can be rotatably inserted into said compression screw hole in a direction from said upper surface of said plate to said lower surface of said plate to cause said screw shaft to threadedly engage with said plate at said lower opening of said compression screw hole and into the bone, and as said screw shaft is advanced into the bone, said bearing annulus axially loads against said screw seat.