Patent ID: 8852242
Filing Date: 2014-10-07
Classification: A61B,A61F,A61M

Abstract:
1. A dilation introduce for orthopedic surgery comprising: a first dilator tube having a distal portion and a proximal portion, the outer surface of the first dilator tube having a first outer radius centered around a first longitudinal axis, and a first longitudinal lumen having a first inner radius; a second dilator tube having a distal portion and a proximal portion, the second dilator tube having a second outer radius centered around a second longitudinal axis, a second longitudinal lumen having a second inner radius centered around the first longitudinal axis, the distal portion of the second dilator tube having a generally semi-annular cross-section, the second lumen configured for removably receiving the first dilator tube for slidable movement within the second lumen, wherein the first longitudinal axis is parallel to and laterally offset from the second longitudinal axis; a third dilator tube having a distal portion and a proximal portion, the third dilator tube having a third outer radius centered around a third longitudinal axis, a third longitudinal lumen having a third inner radius centered around the second longitudinal axis, the distal portion of the third dilator tube having a semi-annular cross-section, the third lumen configured for removably receiving the second dilator tube for slidable movement within the third lumen; wherein the second longitudinal axis is parallel to and laterally offset from the third longitudinal axis, wherein the second dilator tube and the third dilator tube contain cutting flutes on a side, located opposite the opening of the generally semi-annular cross-section; and an access cannula having a distal portion and a proximal portion, the access cannula having a fourth outer radius centered around the third longitudinal axis, a fourth longitudinal lumen having a fourth inner radius centered around the third longitudinal axis, the distal portion of the access cannula having a semi-annular cross-section, the fourth lumen configured for removably receiving the third dilator tube for slidable movement within the fourth lumen, wherein the access cannula has a smooth outer surface, wherein the third dilator tube and the access cannula are removably connected together in a locked arrangement, whereby in the locked arrangement the slidable movement is restricted.