Systems and methods for treating bone using expandable bodies

Abstract

An expandable device is introduced into a cancellous bone volume of a vertebral body through a percutaneous access path. The expandable device is expanded while disposed within the cancellous bone volume to create a cavity. A volume of filling material is placed within the cavity. The filling material includes a therapeutic substance.

1 . A method comprising:
 selecting a vertebral body for treatment, the vertebral body having a cortical wall enclosing a cancellous bone volume,   providing an expandable device including an expanded configuration and an unexpanded configuration,   introducing the expandable device into the vertebral body through a percutaneous access path while in the unexpanded condition,   expanding the expandable device while disposed within the cancellous bone volume from the unexpanded configuration toward the expanded configuration to create a cavity in the cancellous bone volume, and   placing a volume of filling material within the cavity, the filling material including a therapeutic substance.   
     
     
         2 . A method according to  claim 1   further including controlling the expansion so that the expandable device expands more in an inferior-to-superior direction than in a lateral direction.   
     
     
         3 . A method according to  claim 1   wherein the expansion is capable of moving fractured cortical bone toward a desired anatomic position.   
     
     
         4 . A method according to  claim 1   wherein the filling material hardens within the vertebral body.   
     
     
         5 . A method according to  claim 1   wherein the filling material comprises bone cement.   
     
     
         6 . A method according to  claim 1   wherein the expandable device expands by inflation.   
     
     
         7 . A method according to  claim 1   wherein the expandable device comprises a balloon.   
     
     
         8 . A method according to  claim 1   further including removing the expandable device from the vertebral body.   
     
     
         9 . A method according to  claim 2   wherein expansion is controlled by restraining expansion of the expandable device in the lateral direction.   
     
     
         10 . A method according to  claim 9   wherein expansion is restrained by providing restraints external to the expandable device.   
     
     
         11 . A method according to  claim 9   wherein expansion is restrained by providing restraints internal to the expandable device.   
     
     
         12 . A method according to  claim 9   wherein expansion is restrained by providing a wall on the expandable device that varies in wall thickness.   
     
     
         13 . A method according to  claim 1   wherein the therapeutic substance comprises an antibiotic, or a bone growth factor, or an osteoporosis drug.   
     
     
         14 . A system comprising:
 an expandable device including an expanded configuration and an unexpanded configuration sized and configured for introduction into a vertebral body through a percutaneous access path while in the unexpanded condition, the vertebral body having a cortical wall enclosing a cancellous bone volume, the expandable device also being sized and configured for expansion while disposed within the cancellous bone volume to create a cavity in the cancellous bone volume,   a filling material including a therapeutic substance, and   a tool for placing a volume of filling material within the cavity.   
     
     
         15 . A system according to  claim 14   wherein the expandable device is sized and configured to expand more in an inferior-to-superior direction than in a lateral direction.   
     
     
         16 . A system according to  claim 14   wherein the expandable device is sized and configured, when expanding, to move fractured cortical bone toward a desired anatomic position.   
     
     
         17 . A system according to  claim 14   wherein the filling material also comprises bone cement.   
     
     
         18 . A system according to  claim 14   wherein the expandable device expands by inflation.   
     
     
         19 . A system according to  claim 14   wherein the expandable device comprises a balloon.   
     
     
         20 . A system according to  claim 14   wherein the expandable device includes material restraining expansion of the expandable device in the lateral direction.   
     
     
         21 . A system according to  claim 14   wherein the expandable device includes restraints external to the expandable device.   
     
     
         22 . A system according to  claim 14   wherein the expandable device includes restraints internal to the expandable device.   
     
     
         23 . A system according to  claim 14   wherein the expandable device includes a wall that varies in wall thickness.   
     
     
         24 . A system according to  claim 14   wherein the therapeutic substance comprises an antibiotic, or a bone growth factor, or an osteoporosis drug.