US Patent 9681905 Expandable screw and methods of use

An expandable screw includes generally a shaft, a head, and a cut pattern. The shaft includes a longitudinal axis, an outer surface including a thread to engage bone, and an expandable region configurable between a first state with a first radius measured from the longitudinal axis to the outer surface and a second state having a second radius measured from the longitudinal axis to the outer surface. The head coupled with the shaft at a neck is configured to receive a driving instrument to insert and drive the shaft into the bone when the expandable region is in the first state. The cut pattern on the shaft permits at least partial nesting of a first portion of the expandable region within a second portion of the expandable region in the second state.