Expandable attachment device and method

Abstract

An attachment device with a radially expandable section is disclosed. The attachment device can have helical threads, for example, to facilitate screwing the attachment device into a bone. Methods of using the same are also disclosed. The attachment device can be positioned to radially expand the expandable section in cancellous bone substantially surrounded by cortical bone.

1 . An attachment device having a longitudinal axis comprising:
 a radially expandable length comprising a deformable frame, and wherein the frame comprises a plurality of struts, and wherein the plurality of struts defines a plurality of open cells, and   a length configured to attach to a separate device.   
     
     
         2 . The device of  claim 1 , wherein the radially expandable length is configured to radially expand when the radially expandable length is longitudinally contracted. 
     
     
         3 . The device of  claim 1 , wherein the radially expandable length is configured to radially expand when the radially expandable length is rotated. 
     
     
         4 . The device of  claim 1 , wherein the radially expandable length is configured to radially expand when a wedge is translated into the radially expandable length. 
     
     
         5 . The device of  claim 1 , wherein the attachment device further comprises a radially unexpandable length. 
     
     
         6 . The device of  claim 1 , wherein the radially expandable length comprises a cam. 
     
     
         7 . The device of  claim 1 , wherein the radially expandable length comprises a ramp configuration. 
     
     
         8 . The device of  claim 1 , further comprises a threaded length. 
     
     
         9 . The device of  claim 8 , wherein the threaded length is on the opposite side of the radially expandable length from the length configured to attach to a separate device. 
     
     
         10 . The device of  claim 9 , wherein the threaded length is radially unexpandable. 
     
     
         11 . The device of  claim 1 , wherein the length configured to attach to a separate device has a substantially spherical configuration. 
     
     
         12 . The device of  claim 1 , wherein the length configured to attach to a separate device has an interface configured to attach to a removable deployment tool. 
     
     
         13 . A method for deploying an attachment device having a longitudinal axis in a bone comprising:
 inserting the attachment device of  claim 1  into the bone,   radially expanding a radially expandable length of the attachment device.   
     
     
         14 . The method of  claim 13 , wherein radially expanding comprises radially expanding a radially expandable length of the attachment device in a cancellous portion of the bone. 
     
     
         15 . The method of  claim 13 , wherein inserting comprises inserting into a vertebral body. 
     
     
         16 . The method of  claim 13 , wherein radially expanding comprises longitudinal compressing the attachment device. 
     
     
         17 . The method of  claim 13 , wherein radially expanding comprises rotating the attachment device. 
     
     
         18 . The method of  claim 13 , wherein radially expanding comprises inserting a leverage element into the attachment device. 
     
     
         19 . The method of  claim 18 , wherein the leverage element comprises a wedge. 
     
     
         20 . The method of  claim 13 , wherein the attachment device comprises a resilient section, and wherein radially expanding comprises releasing a mechanical constraint from the resilient section.