Cannulated screw and associated driver system
AssigneeEthicon, Inc.
InventorsJ. Jenny Yuan, Thomas M. Poandl
Life of this patent
Estimating the term…
Abstract
A driver for inserting cannulated screws has a tool portion, e.g., in the form of a hex wrench that slips into the cannula of the screw. A tapered threaded tip on the tool extends beyond the front tip of the screw. An abutment surface provided, e.g., by the tool holder acts as a limit to rearward motion of the screw when it is being screwed into a substrate such as bone. The threaded tip of the tool cuts the bone to allow the threads of the cannulated screw to follow into the substrate permitting use of a softer material, such as a bioabsorbable material for the screw.
Claims20
A driver for threading a cannulated screw into a substrate, comprising:
- a tool with a screw engaging portion and a threaded tip, said screw engaging portion extendable through a cannula formed in the cannulated screw, said screw engaging portion having a shape that substantially prevents rotation of said screw engaging portion relative to the cannula screw when said screw engaging portion is extending through the cannula of the cannulated screw, said threaded tip extending beyond the screw when said screw engaging portion is inserted into the cannula of the cannulated screw.
A system for fastening orthopedic prosthesis, comprising:
- a screw with an axial cannula;
- a tool with a screw engaging portion and a threaded tip, said screw engaging portion extendable through said cannula, said screw engaging portion having a shape that substantially prevents rotation of said screw engaging portion relative to said cannula, when said screw engaging portion is extending through said cannula of the cannulated screw, said threaded tip extending beyond said screw when said screw engaging portion is inserted into said cannula.
A method for introducing cannulated screws into a substrate with a tool with a screw engaging portion extendable through the cannulated screw, the engaging portion having a shape that substantially prevents rotation of the screw engaging portion relative to the cannula, comprising the steps of:
- (A) providing the screw engaging portion with a length greater than that of the screw;
- (B) extending the screw engaging portion through the cannulated screw, a tip of the screw engaging portion extending beyond the screw:
- (C) providing threads on the tip of the screw engaging portion;
- (D) drilling a pilot hole into the substrate;
- (E) inserting the tip of the screw engaging portion into the pilot hole;
- (F) turning the screw engaging portion and the tip thereof;
- (G) threading the threads of the tip into the pilot hole;
- (H) continuing to turn the screw engaging portion to draw the tip deeper into the pilot hole and introducing the screw into the pilot hole.
Dependencies are inferred from the claim text.