Vertebral Disc Auger

Abstract

A medical instrument for shaving, collecting, and removing vertebral disc material from a vertebral disc space of a spine, has a shaft defining a proximal shaft end and a distal shaft end, and an auger at the distal shaft end. The auger has a plurality of helical cutting flutes configured to shave and collect vertebral disc material from the vertebral disc through rotation of the auger. Each helical cutting flute has a cutting apex that together define a cutting tip, and a radially inward helical slot that collectively define an internal cavity for collection of cut vertebral disc material. The plurality of cutting apexes converge at the cutting tip, defining a point. The medical instrument includes a connector to allow attachment of a handle. A notch in the proximal shaft end that receives a flange of the handle prevents rotation of the handle relative to the auger.

What is claimed is: 
     
         1 . A medical instrument for obtaining vertebral disc material from a vertebral disc in a vertebral disc space of a spine during a surgical spine procedure, the medical instrument comprising:
 a shaft having a proximal shaft end and a distal shaft end;   a handle portion at the proximal shaft end; and   an auger formed at the distal shaft end, the auger having a plurality of helical cutting flutes configured to shave and collect vertebral disc material from a vertebral disc in a vertebral disc space of a spine through rotation of the shaft, each one of the plurality of helical cutting flutes having a cutting apex that all together define a cutting tip, with each one of the plurality of helical cutting flutes having a radially inward helical slot that collectively define an internal cavity in the auger for collection of cut vertebral disc material.   
     
     
         2 . The medical instrument of  claim 1 , wherein the plurality of cutting apexes converge at the cutting tip to define a point. 
     
     
         3 . The medical instrument of  claim 2 , wherein the plurality of helical cutting flutes comprises three helical cutting flutes. 
     
     
         4 . The medical instrument of  claim 1 , wherein the handle portion comprises a handle. 
     
     
         5 . The medical instrument of  claim 1 , wherein:
 the handle portion comprises a cylindrical body defining a proximal cylindrical body end and a distal cylindrical body end with the distal cylindrical body end connected to the distal shaft end; and   the proximal cylindrical body end has a connector configured to allow attachment of a handle to the handle portion.   
     
     
         6 . The medical instrument of  claim 5 , wherein the proximal cylindrical body end has a notch that receives a flange of the handle for preventing rotation of the handle relative to the cylindrical body. 
     
     
         7 . The medical instrument of  claim 6 , wherein the proximal cylindrical body end has depth markings. 
     
     
         8 . The medical instrument of  claim 1 , wherein the auger extends from a neck at the distal shaft end with each one of the plurality of helical cutting flutes having a proximal end that extends from the neck, each one of the proximal ends of the helical cutting flutes having a surface sloped radially inward from the neck. 
     
     
         9 . A method of removing vertebral disc material from a vertebral disc in a vertebral disc space of a spine comprising:
 providing an incision in a patient proximate a vertebral disc to be cut;   inserting a tube having a proximal tube end and a distal tube end into the incision such that the distal tube end is proximate to the vertebral disc to be cut;   providing a medical instrument having a shaft defining a proximal shaft end and a distal shaft end, a handle portion at the proximal shaft end, and an auger formed at the distal shaft end, the auger having a plurality of helical cutting flutes configured to shave and collect vertebral disc material from a vertebral disc in a vertebral disc space of a spine through rotation of the shaft, each one of the plurality of helical cutting flutes having a cutting apex that all together define a cutting tip, with each one of the plurality of helical cutting flutes having a radially inward helical slot that collectively define an internal cavity in the auger for collection of cut vertebral disc material; and   placing the medical instrument into and through the tube such that the auger extends from the distal tube end and is adjacent the vertebral disc to be cut;   rotating the medical instrument to rotate the auger into the vertebral disc to cut vertebral disc material from the vertebral disc; and   removing the medical instrument from the tube.   
     
     
         10 . The method of  claim 9 , wherein the plurality of cutting apexes converge at the cutting tip to define a point. 
     
     
         11 . The method of  claim 10 , wherein the plurality of helical cutting flutes comprises three helical cutting flutes. 
     
     
         12 . The method of  claim 9 , wherein the handle portion comprises a handle. 
     
     
         13 . The method of  claim 9 , wherein:
 the handle portion comprises a cylindrical body defining a proximal cylindrical body end and a distal cylindrical body end with the distal cylindrical body end connected to the distal shaft end; and   the proximal cylindrical body end has a connector configured to allow attachment of a handle to the handle portion.   
     
     
         14 . The method of  claim 13 , wherein the proximal cylindrical body end has a notch that receives a flange of the handle for preventing rotation of the handle relative to the cylindrical body. 
     
     
         15 . The method of  claim 13 , wherein the proximal cylindrical body end has depth markings. 
     
     
         16 . The method of  claim 9 , wherein the auger extends from a neck at the distal shaft end with each one of the plurality of helical cutting flutes having a proximal end that extends from the neck, each one of the proximal ends of the helical cutting flutes having a surface sloped radially inward from the neck.