Methods of Stabilizing the Sacroiliac Joint

Abstract

Methods of stabilizing the sacroiliac joint by placing an expandable device in the joint to generate laterally opposing forces against the iliac and sacral surfaces of the SI joint to securely seat the device in a plane generally parallel to the SI joint. The expandable device is coated with or otherwise contains a bone material to promote fusion of the joint. The expandable device used in methods of the present invention can be, for example, an expandable cage, a balloon, a balloon-expandable stent or a self-expanding stent.

We claim: 
     
         1 . An implant for stabilizing a sacroiliac joint in a patient in need thereof comprising:
 a screw having a tip and a shaft, at least a portion of the shaft includes threads;   an expandable body having a distal end, a proximal end and defining a cavity and at least one opening in communication with (i) the cavity and (ii) an outer surface of the body, and the expandable body being fitted over at least a portion of the shaft of the screw with the distal end of the expandable body capable of contacting the tip of the screw;   a nut member, the nut member capable of engaging the threaded portion and capable of contacting the proximal end of the expandable body;   the device having an unexpanded configuration in a non-deployed state and a radially expanded configuration in a deployed state;   wherein the implant is radially expanded to engage the sacroiliac joint to securely seat the device in the sacroiliac joint by rotating the nut member thereby compressing the expandable body between the tip and the nut member.   
     
     
         2 . The implant of claim I, wherein placing a bone material on the expandable body comprises providing a device comprising an expandable body having an outer surface coated with a bone material. 
     
     
         3 . The implant of  claim 1 , wherein the at least one opening is a plurality of openings. 
     
     
         4 . The implant of  claim 3 , wherein the expandable body comprises a plurality of strips that extend from the proximal end to the distal end of the body, the plurality of strips defining a plurality of openings therebetween. 
     
     
         5 . The implant of  claim 1 , wherein the screw comprises: (a) a shaft having a proximal end and a distal end and (b) a pointed, cutting distal tip extending from the shaft, wherein the expandable body is mounted on the shaft. 
     
     
         6 . The implant of  claim 5 , wherein the shaft defines a channel extending from the proximal end to the distal end of the shaft. 
     
     
         7 . The implant of  claim 5 , wherein the device further comprises a locking nut sized to threadably engage the shaft of the screw. 
     
     
         8 . The implant of  claim 1 , wherein the expandable body is fabricated from a biodegradable material. 
     
     
         9 . The implant of  claim 5 , wherein the screw is fabricated from a biodegradable material. 
     
     
         10 . The implant of  claim 7 , wherein the locking nut is fabricated from a biodegradable material. 
     
     
         11 . The implant of  claim 1 , wherein the bone material is a bone graft. 
     
     
         12 . The implant of  claim 1 , wherein the bone material is a bone morphogenetic protein. 
     
     
         13 . The implant of  claim 1 , wherein the device is inserted into the sacroiliac joint percutaneously. 
     
     
         14 . The implant of  claim 1 , further comprising placing a bone material within the cavity of the expandable body of the device to permit fusion of the sacroiliac joint. 
     
     
         15 . An implant for stabilizing a sacroiliac joint comprising:
 a screw having a tip and a shaft, at least a portion of the shaft includes threads;   an expandable body having a distal end, a proximal end and defining a cavity and at least one opening in communication with (i) the cavity and (ii) an outer surface of the body, and the expandable body being fitted over at least a portion of the shaft of the screw with the distal end of the expandable body capable of contacting the tip of the screw;   a nut member, the nut member capable of engaging the threaded portion and capable of contacting the proximal end of the expandable body;   the device having an unexpanded configuration in a non-deployed state and a radially expanded configuration in a deployed state;   wherein the implant is radially expanded to engage the sacroiliac joint to securely seat the device in the sacroiliac joint.   
     
     
         16 . The implant of  claim 15 , wherein placing a bone material on the expandable body comprises providing a device comprising an expandable body having an outer surface coated with a bone material. 
     
     
         17 . The implant of  claim 15 , wherein the at least one opening is a plurality of openings. 
     
     
         18 . The implant of  claim 17 , wherein the expandable body comprises a plurality of strips that extend from the proximal end to the distal end of the body, the plurality of strips defining a plurality of openings therebetween. 
     
     
         19 . The implant of  claim 15 , wherein the screw comprises: (a) a shaft having a proximal end and a distal end and (b) a pointed, cutting distal tip extending from the shaft, wherein the expandable body is mounted on the shaft. 
     
     
         20 . An implant for stabilizing a sacroiliac joint comprising:
 a screw having a tip and a shaft, at least a portion of the shaft includes threads;   an expandable body having a distal end, a proximal end and defining a cavity and at least one opening in communication with (i) the cavity and (ii) an outer surface of the body, and the expandable body being fitted over at least a portion of the shaft of the screw with the distal end of the expandable body capable of contacting the tip of the screw;   a nut member, the nut member capable of engaging the threaded portion and capable of contacting the proximal end of the expandable body;   the device having an unexpanded configuration in a non-deployed state and a radially expanded configuration in a deployed state; and   a locking nut sized to threadably engage the shaft of the screw;   wherein the implant is radially expanded to engage the sacroiliac joint to securely seat the device in the sacroiliac joint by rotating the nut member thereby compressing the expandable body between the tip and the nut member,