STRAIN REGULATING FUSION CAGE FOR SPINAL FUSION SURGERY

摘要

Intervetebral fusion cage comprising a prismatic, conical or cylindrical cage(1) having A) a central axis (2); B) an upper and lowerbone contact surface (3; 4) transverse to said central axis (2); C) a centralcavity (5) for receiving bone graft material and extending betweensaid lower contact surface (4) and said upper contact surface (3) through saidbody (1) defining a circumferential sidewall (10) arrangedcoaxially to said central axis (2); and D) a plurality of sectorial slots (6;7; 8; 9) perforating the circumferential sidewall (10) transverselyto the central axis (2), whereby E) said slots (6; 7; 8; 9) have a minimawidth (h1; h2; h3, h4) that upon compressing of the body (1) alongthe central axis (2) said slots (6; 7; 8; 9) close elastically at the minimalwidths (h1; h2; h3; h4) thereby increasing the stiffeness of the cage(1) upon further compression.