Patent ID: 9572598
Date: 2017-02-21
CPC Classifications: A61B

Claim:
1. A uniplanar surgical screw assembly comprising: a fastener including an elongate shaft having a proximal end and a distal end and a head at said proximal end, said head having an external surface; a saddle-shaped tulip having a tulip proximal end, a tulip distal end, an external surface and an internal bearing surface, said tulip distal end having a bore therethrough dimensioned to allow said distal end of said elongate shaft to pass therethrough, but to prevent passage of said head therethrough; a slot formed in one of said external surface of said head or said internal bearing surface of said tulip, said slot having a width dimension and a length dimension greater than said width dimension, wherein said length dimension extends in a proximal-distal direction of said head or said tulip and wherein said slot is bounded in said proximal-distal direction by proximal and distal ends of said slot, respectively; and a protrusion extending from the other of said external surface of said head or said internal bearing surface of said tulip, said protrusion being configured and dimensioned to be received within said slot and to slide in said slot, relative to said slot; wherein said slot and said protrusion permit said fastener to move relative to said tulip in only one plane; and wherein said proximal and distal ends of said slot limit movement of said fastener relative to said tulip in said proximal-distal direction, upon respective contact with said protrusion.