Self-locking bone screw and implant
AssigneeEbi, LLC
InventorPeter M. Harris
Life of this patent
Estimating the term…
Abstract
The invention relates to an orthopedic implant assembly having a flange member having a through bore with internal threads and a screw which has a single continuous thread that has a first section and a second section. The cross sectional configuration of the thread in the first section is different than the cross sectional configuration in the second section. The first section defines a cancellous thread while the second section defines a locking thread which is an asymmetrical buttress thread that has the same pitch and angle along the leading or thrust surface as the cancellous thread and a thicker square spiral edge or face joined to a transverse rear surface.
Claims13
An orthopedic implant assembly comprising an implant having at least one through bore having internal threads and a screw which has a longitudinal axis and having a single continuous thread having a first section and a second section along the longitudinal axis, wherein the thread has a cancellous configuration along the first section and a locking configuration along the second section which corresponds to the shape of the second section, and wherein the thread had a leading face along the spiral which has the same pitch for the first section and the second section.
An orthopedic implant for surgical implantation comprising a flange member having an internally threaded through bore and a screw having a longitudinal axis wherein the screw has a single thread which has a first section with a first cross-sectional configuration and a second section with a second cross-sectional configuration, and the first configuration is a cancellous thread wherein the leading surface has a given pitch which forms an angle of from about 20 to about 30 degrees to a line perpendicular to the longitudinal axis and the second to a line perpendicular to the longitudinal axis and the second configuration has the given pitch and the same angle as the first configuration and wherein the rear surface of the first configuration is at an angle of about 0 to about 5 degrees to the line perpendicular to the longitudinal axis and the rear surface of the second configuration has an angle of from about 0 to about 5 degrees to the line perpendicular to the longitudinal axis and wherein the thread of the screw defines one major diameter in the first and second section and the screw has a first minor diameter in the first section and a second minor diameter in the second section and the first minor diameter is smaller than the second minor diameter and the thread has a spiral edge of a first thickness in the first section and a spiral edge of a second thickness in the second section and the second thickness is greater than the first section and the spiral edge in the second section is at an angle of about 85 to 95 degrees to the rear surface in the second configuration.
Dependencies are inferred from the claim text.