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 lower bone contact surface (3; 4) transverse to said central axis (2); C) a central cavity (5) for receiving bone graft material and extending between said lower contact surface (4) and said upper contact surface (3) through said body (1) defining a circumferential sidewall (10) arranged coaxially to said central axis (2); and D) a plurality of sectorial slots (6; 7; 8; 9) perforating the circumferential sidewall (10) transversely to the central axis (2), whereby E) said slots (6; 7; 8; 9) have a minima width (h1; h2; h3, h4) that upon compressing of the body (1) along the central axis (2) said slots (6; 7; 8; 9) close elastically at the minimal widths (h1; h2; h3; h4) thereby increasing the stiffeness of the cage (1) upon further compression.