Patent ID: 8460349

Claim:
A device for manipulating bone fragments, comprising: a bone screw including a shaft extending along a longitudinal axis, the shaft including a first end having a first threaded portion with a first core diameter, a first external diameter and a first pitch, a second end having a second threaded portion with a second core diameter, a second external diameter and a second pitch, the second end further having a tool engaging surface, wherein the first external diameter is no greater than the second core diameter, the first and second pitches are substantially equal, and a non-threaded middle segment between the first and second threaded portions, an outer diameter of the middle segment being smaller than the first core diameter, and wherein the shaft includes a cannulation extending therethrough disposed coaxial with the screw longitudinal axis; and an installation instrument including first and second ends, a longitudinal axis, and a bore extending along at least a portion of the longitudinal axis, the bore in communication with the first end of the instrument, wherein the bore has threads along at least a portion of a length thereof, the threads configured to mate with the second threaded portion of the bone screw so that rotating the installation instrument rotates the bone screw to drive the screw into a bone.