Bone dilator system and methods

Abstract

Disclosed are surgical tools, tool sets and methods for percutaneously accessing and preparing treatment sites within the spine for subsequent treatment procedures. The treatment site may be an inter-vertebral motion segments in the lumbar and sacral regions of the spine. The tool set may comprise introducer tools and bone dilators for accessing and tapping into a targeted site, such as, for example, the anterior surface of the S1 vertebral body. The tool set may also comprise cutters and extractors for preparing the treatment site for subsequent treatment procedures. The tool set may additionally comprise a bone graft inserter, an exchange system, and/or a temporary distraction tool for further preparing the treatment site for subsequent treatment procedures.

1 . A method of enlarging a bore in bone, comprising the steps of:
 advancing a first tubular dilator, having a first diameter, over a guide pin and into the bone;   removing the first tubular dilator; and   advancing at least a second tubular dilator, having a second, greater diameter, over the guide pin and into the bone.   
   
   
       2 . A method of enlarging a bore in bone as in  claim 1 , wherein at least one of the advancing steps is accomplished using a cannulated slap hammer. 
   
   
       3 . A method of enlarging a bore in bone as in  claim 1 , further comprising advancing a third tubular dilator over the guide pin and into the bone. 
   
   
       4 . A method of positioning a tubular access sheath in communication with a site in a bone, comprising the steps of:
 advancing a first tubular dilator, having a first diameter, over a guide pin and into the bone;   removing the first tubular dilator;   advancing at least a second tubular dilator, having a second, greater diameter and a removable tubular sheath, over the guide pin and into the bone; and   removing the second tubular dilator, leaving the tubular sheath in position to provide access to the site in the bone.   
   
   
       5 . A method of using a bone dilator system, for enlarging the diameter of a bore through bone, the bone dilator system comprising: a first cannulated rod, having an outer diameter, a proximal end and a distal end; a handle on the proximal end; and a cannulated slap hammer, for reciprocal movement over a guide pin extending through the cannulated rod and slap hammer; the method comprising:
 inserting the first cannulated rod into the bore; and   enlarging the bore by inserting a second cannulated rod into the bore, the second cannulated rod having an outer diameter greater than the outer diameter of the first cannulated rod.   
   
   
       6 . The method of using a bone dilator system as in  claim 5 , the bone dilator system further comprising a guide pin. 
   
   
       7 . The method of using a bone dilator system as in  claim 5 , the bone dilator system further comprising a tapered tip on the distal end. 
   
   
       8 . The method of using a bone dilator system as in  claim 5 , the bone dilator system wherein the second cannulated rod, having a greater lumen diameter than the outer diameter of the first cannulated rod, is inserted over the first cannulated rod into the bore. 
   
   
       9 . The method of using a bone dilator system as in  claim 8 , further comprising at least a third cannulated rod, having a greater diameter than the second cannulated rod. 
   
   
       10 . The method of using a bone dilator system as in  claim 8 , further comprising a tubular sheath, wherein at least one cannulated rod is removably positionable within the tubular sheath. 
   
   
       11 . The method of using a bone dilator system as in  claim 10 , further comprising a first retention structure on the sheath and a second, complementary retention structure on the at least one cannulated rod, to releasably attach the sheath to the at least one cannulated rod. 
   
   
       12 . A method of using a bone dilator kit, for increasing the diameter of a bore through bone, the bone dilator kit comprising: a first cannulated rod having a proximal handle and a first diameter; a second cannulated rod having a proximal handle and a second diameter; a third cannulated rod having a proximal handle and a third diameter, the first diameter being less than the second diameter, the second diameter being less than the third diameter, the method comprising:
 inserting the first cannulated rod into the bore to enlarge a diameter of the bore;   inserting the second cannulated rod into the bore enlarged by the first cannulated rod to enlarge the diameter of the bore; and   inserting the third cannulated rod into the bore enlarged by the second cannulated rod to enlarge the diameter of the bore.   
   
   
       13 . The method of using a bone dilator kit as in  claim 12 , the bone dilator kit further comprising a slap hammer. 
   
   
       14 . The method of using a bone dilator kit as in  claim 12 , wherein at least one of the first, second and third diameters is about 6 mm. 
   
   
       15 . The method of using a bone dilator kit as in  claim 12 , wherein at least one of the first, second and third diameters is about 8 mm. 
   
   
       16 . The method of using a bone dilator kit as in  claim 12 , wherein at least one of the first, second and third diameters is about 10 mm. 
   
   
       17 . The method of using a bone dilator kit as in  claim 12 , the bone dilator kit further comprising a tubular sheath having a central lumen dimensioned to axially slidably receive at least one of the cannulated rods. 
   
   
       18 . The method of using a bone dilator kit as in  claim 17 , the bone dilator kit further comprising a lock for releasably retaining the sheath on the at least one rod.