Patent ID: 7074226

Claim:
A dilator for use in soft tissue of a human body to provide an access channel to a planned surgery site adjacent the spine and comprising: a tube having a proximal end and a distal end and a longitudinal axis; and said tube including an external surface and a channel extending between said proximal and distal ends along said longitudinal axis, each of said external surface and said channel having a non-circular cross-sectional shape in a plane perpendicular to said longitudinal axis at a first location proximate said distal end, wherein the cross-sectional shape of said channel differs from the cross-sectional shape of said external surface and said external surface includes parallel sides and circular ends extending between said parallel sides at least adjacent said distal end of said tube and, wherein said cross-sectional shapes of said channel and said external surface extend from said first location proximate said distal end to a second location at least eighty percent of the distance from said distal end to said proximal end.