Apparatus and methods for bone access and cavity preparation

Abstract

Apparatus and methods for preparing the interior of a bone for therapy. The therapy may include therapy for a bone fracture. The apparatus and methods may involve orienting a surgical instrument for proper deployment in the interior of the bone. An instrument guide may be positioned and retained against translation along, and rotation about one or more of three substantially orthogonal axes. Apparatus placed exterior to the bone may register the guide to a region inside the bone that is designated for preparation or treatment. One or more broaching members may be used to prepare the region for treatment. A broaching member may be expandable inside the bone. A broaching member may be flexible such that it broaches bone having a relatively lower density and it leaves bone having a relatively higher density substantially intact.

1 - 34 . (canceled) 
     
     
         35 . A method for creating a cavity in a bone, the method comprising:
 providing a laser-cut tube;   inserting the tube inside the hone;   expanding the tube to form a mesh comprising numerous interconnected cells; and   rotating the mesh to displace bone tissue.   
     
     
         36 . The method of  claim 35  wherein the tube is self-expanding. 
     
     
         37 . The method of  claim 35  wherein the tube is formed from nitinol. 
     
     
         38 . The method of  claim 35  wherein the rotating includes drawing a cell edge along the bone tissue. 
     
     
         39 . The method of  claim 35  wherein the rotating includes drawing a cutting edge of a cell along the bone tissue. 
     
     
         40 . The method of  claim 35  wherein the rotating includes drawing a plurality of cell edges along the hone tissue. 
     
     
         41 . The method of  claim 35  wherein the rotating includes drawing a network of cells along the bone tissue. 
     
     
         42 . The method of  claim 35  wherein rotating includes rotating a rotator coupled to the mesh. 
     
     
         43 . The method of  claim 42  wherein the rotating includes rotating a flexible drive shaft coupled to the meth. 
     
     
         44 . The method of  claim 42  wherein the rotating includes rotating a broach shaft coupled to the mesh, the broach shaft including stress-relief cuts. 
     
     
         45 . The method of  claim 35  further comprising adjusting a position of the mesh in the bone. 
     
     
         46 . The method of  claim 45  further comprising changing an elevation of the mesh within the bone relative to a surface of the bone. 
     
     
         47 . The method of  claim 35  wherein the rotating is continuous. 
     
     
         48 . The method of  claim 35  wherein the rotating is pulsed. 
     
     
         49 . The method of  claim 35  wherein the rotating alternates between a first rotational direction and a second rotational direction. 
     
     
         50 . The method of  claim 35  wherein the rotating includes cutting bone tissue. 
     
     
         51 . The method of  claim 35  wherein the rotating includes displacing first bone material, the cells substantially deflecting around second bone material having a higher density than the that bone material. 
     
     
         52 . The method of  claim 51  wherein the rotating includes displacing cancellous bone and deflecting around cortical bone. 
     
     
         53 . The method of  claim 35  wherein the expanding includes displacing bone tissue radially away from a rotator coupled to the mesh.