Method and apparatus for removing material from an intervertebral disc space, such as in performing a nucleotomy

Abstract

Instrument and method for removing material from an intervertebral disc. The instrument includes outer and inner tubular members. The outer tubular member defines a passage and a cutting window. The inner tubular member is coaxially disposed within the passage, and defines a central lumen and a cutting tip. The cutting tip forms an open mouth having a plurality of teeth. Upon assembly, the cutting tip is exposed within the cutting window combining to define a shaving head. A powered handpiece is coupled to the inner tubular member, and the shaving head is inserted into an intervertebral disc and positioned such that the cutting tip contacts targeted material (e.g., nucleus, annulus and/or end plate). The handpiece is activated to rotate the cutting tip relative to the cutting window. Contacted material is sheared between an edge of the cutting window and the teeth of the cutting tip.

1 . A surgical intervertebral disc material shaving instrument for use with a powered handpiece, the instrument comprising:
 an elongated outer tubular member defining a central passage and a cutting window at a distal end thereof, the cutting window being fluidly connected to the central passage and defined by a perimeter edge forming at least four teeth on a first longitudinal side and at least four teeth on a second longitudinal side thereof; and   an inner tubular member coaxially disposed within the central passage, the inner tubular member defining a central lumen and a cutting tip at a distal end thereof, the cutting tip including a plurality of circumferentially-extending teeth formed about at least a portion of a mouth otherwise fluidly connected to the lumen;   wherein upon final assembly, the cutting tip is exposed within the cutting window, the cutting tip and cutting window combining to define a shaving head configured to shear intervertebral disc material and aspirate sheared material through the mouth and lumen.   
     
     
         2 . The instrument of  claim 1 , wherein the cutting tip has a diameter in the range of 3-8 mm. 
     
     
         3 . The instrument of  claim 2 , wherein the cutting tip has an outer diameter of 4.5 mm. 
     
     
         4 . The instrument of  claim 1 , wherein the outer tubular member includes a proximal segment and a distal segment, the distal segment forming the cutting window and extending at an angle relative to a longitudinal axis of the proximal segment in the range of 0-90°. 
     
     
         5 . The instrument of  claim 4 , wherein the distal segment extends at an angle in the range of 20-45° relative to the proximal segment. 
     
     
         6 . The instrument of  claim 5 , wherein the distal segment extends at an angle of 45° relative to the proximal segment. 
     
     
         7 . The instrument of  claim 1 , wherein the distal segment extends from the distal end to the bend, the distal segment having a length in the range of 1-3.5 cm. 
     
     
         8 . The instrument of  claim 7 , wherein the distal segment has a length of 2.5 cm.