Title:
【発明の名称】改良されたねじ山を有する骨ねじ
Document Type and Number:
Japanese Patent JPH06504456
Kind Code:
A
Abstract:
A bone screw having a helical thread that gradually increases in thickness from the tip to the head of the screw. The thin thread at the tip of the screw can be inserted into a bone with minimal tearing or cracking of the bone. The thicker treads ascending form the tip to the head of the screw displaces bone against the superior (top) thread surfaces. This displacement of bone increases the screw's resistance to being pulled-out of the bone. The thicker core just below the screw head increases the screw's ability to withstand compressive and distractive loads. The core is thickest just below the head because it is at that point on the screw that the fulcrum loads are greatest.
Inventors:
Winkler, Heinz
Application Number:
JP50156192A
Publication Date:
May 26, 1994
Filing Date:
November 26, 1991
Export Citation:
Assignee:
Razner, Jeffrey
International Classes:
A61B17/86; F16B25/00; A61F2/28; F16B25/04; F16B33/02; (IPC1-7): A61F2/28; F16B25/04
Attorney, Agent or Firm:
Takehiko Suzue (3 outside)