Method for decompressing herniated intervertebral discs

Claim 1

A method for decompressing a herniated intervertebral disc in the lumbar region of a human patient comprising the steps of: inserting a hollow needle with a stylet through the skin of the patient's back at a location spaced from the midline of the back and advancing the needle in an oblique direction with respect to a line perpendicular to the patient's back until it reaches the outside of the annulus fibrosis of the herniated disc; withdrawing the stylet; introducing a guide wire through the needle to the disc; withdrawing the needle; passing a cannulated, blunt-tipped trocar with an opening in its tip slightly greater in diameter than the diameter of the guide wire, over the guide wire until the tip reaches the outside of the annulus fibrosis of the herniated disc; withdrawing the guide wire; passing a thin-walled cannula which closely fits the trocar, over the trocar until the distal end of the cannula reaches outside of said annulus; withdrawing the trocar; introducing through the cannula a cutting instrument comprising a hollow circular cylindrical tube having cutting teeth formed in a circle on its distal end; with the cannula still in place, forming a window in the herniated disc by rotary manipulation of the cutting instrument; and with the cannula still in place, evacuating fragments of the herniated disc through the cannula.

Claim 2

A method for decompressing a herniated intervertebral disc in the lumbar region of a human patient comprising the steps of: inserting a hollow needle with a stylet through the skin of the patient's back at a location spaced from the midline of the back and advancing the needle in an oblique direction with respect to a line perpendicular to the patient's back until it reaches the outside of the annulus fibrosis of the herniated disc; withdrawing the stylet; introducing a guide wire through the needle to the disc; withdrawing the needle; passing a cannulated, blunt-tipped trocar with an opening in its tip slightly greater in diameter than the diameter of the guide wire, over the guide wire until the tip reaches the outside of the annulus fibrosis of the herniated disc; withdrawing the guide wire; passing a thin-walled cannula which closely fits the trocar, over the trocar until the distal end of the cannula reaches outside of said annulus; withdrawing the trocar; introducing through the cannula a cutting instrument comprising a hollow circular cylindrical tube having cutting teeth formed in a circle on its distal end; with the cannula still in place, forming a window in the herniated disc by rotary manipulation of the cutting instrument; and with the cannula still in place, evacuating fragments of the herniated disc through the cannula.