Sacroiliac Joint Implants and Implantation Methods

Abstract

Sacroiliac (SI) joint implants for promoting SI joint fusion and methods of their delivery are described herein. The SI joint implant has a spacer operatively coupled to a planar member having tapered holes to receive fastening elements. When placed in the SI joint, the spacer engages the articular surfaces of the SI joint while the plate traverses the SI joint. The implant is held in place fastening elements, which are inserted through the tapered holes in the planar member. The implant is delivered via an inferior inlet MIS procedure, wherein the SI joint is accessed through an inlet inferior to the SI joint.

I claim: 
     
         1 . A method for delivering a sacroiliac joint implant to the inferior aspect of the sacroiliac joint comprising:
 making an incision in the inferior posterior lumbosacral region of a patient;   inserting an instrument suitable for preparing a joint space through the incision and into the SI joint through the inferior aspect of the SI joint; and   delivering a SI joint implant to the inferior aspect of the SI joint.   
     
     
         2 . The method of  claim 1 , wherein the incision is approximately one inch or less. 
     
     
         3 . The method of  claim 1 , wherein the SI joint implant comprises a spacer comprising a first longitudinal axis and two opposing surfaces, wherein the two opposing surfaces extend along the first longitudinal axis;
 wherein the spacer is operatively coupled to a planar member comprising a tapered hole and a second longitudinal axis, wherein the planar member is operatively coupled to the spacer such that the second longitudinal axis is non-parallel, preferably perpendicular, to the first longitudinal axis; and   wherein the implant is aligned within the joint space such that the opposing surfaces of the spacer engage both of the opposing articular surfaces of the sacroiliac joint and the planar member traverses the inferior aspect of the sacroiliac joint.   
     
     
         4 . The method of  claim 1 , wherein the instruments and the SI joint implant are delivered to the inferior aspect of the SI joint at an angle of less than 90 degrees. 
     
     
         5 . The method of  claim 3 , wherein the planar member further comprises a second tapered hole. 
     
     
         6 . The method of  claim 5 , further comprising inserting a fastening element into the tapered holes. 
     
     
         7 . The method of  claim 6 , wherein the fastening element is selected from the group consisting of a screw, a nail, a pin, a rod, and combinations thereof. 
     
     
         8 . The method of  claim 6 , wherein an initial position of the fastening element is off-center within the tapered holes. 
     
     
         9 . A method of fusing the sacroiliac joint in a patient in need thereof, comprising:
 inserting into a joint space of the sacroiliac joint a spacer comprising a first longitudinal axis and two opposing surfaces, wherein the two opposing surfaces extend along the first longitudinal axis;   wherein the spacer is operatively coupled to a planar member comprising a tapered hole and a second longitudinal axis, wherein the planar member is operatively coupled to the spacer such that the second longitudinal axis is non-parallel, preferably perpendicular, to the first longitudinal axis; and   wherein the implant is aligned within the joint space such that the opposing surfaces of the spacer engage both of the opposing articular surfaces of the sacroiliac joint and the planar member traverses the inferior aspect of the sacroiliac joint.   
     
     
         10 . The method of  claim 9 , wherein the spacer and the planar member are operatively coupled in situ. 
     
     
         11 . The method of  claim 9 , wherein the spacer and the planar member are operatively coupled ex vivo. 
     
     
         12 . The method of  claim 9 , wherein the planar member is substantially straight. 
     
     
         13 . The method of  claim 9 , wherein the planar member is curved. 
     
     
         14 . The method of  claim 9 , wherein the planar member further comprises a second tapered hole. 
     
     
         15 . The method of  claim 14 , further comprising inserting a fastening element into the tapered holes. 
     
     
         16 . The method of  claim 15 , wherein the fastening element is selected from the group consisting of a screw, a nail, a pin, a rod, and combinations thereof. 
     
     
         17 . The method of  claim 15  wherein an initial position of the fastening element is off-center within the tapered holes. 
     
     
         18 . The method of  claim 9 , wherein the sacroiliac joint space is accessed using a minimally invasive inferior inlet approach. 
     
     
         19 . A system for fusing the sacroiliac joint in a patient in need thereof, comprising:
 a spacer configured for engaging both articular surfaces of the sacroiliac joint, the spacer comprising a first longitudinal axis and two opposing surfaces extending along the first longitudinal axis; and   a planar member comprising a second longitudinal axis and a tapered hole located at a point along the second longitudinal axis, wherein the planar member is operatively coupled to the spacer such that the second longitudinal axis is non-parallel, preferably perpendicular, to the first longitudinal axis and traverses the inferior aspect of the sacroiliac joint when placed in vivo.   
     
     
         20 . The system of  claim 19 , wherein the planar member is substantially straight. 
     
     
         21 . The system of  claim 19 , wherein the planar member is curved. 
     
     
         22 . The system of  claim 19 , wherein the planar member is has a second tapered hole. 
     
     
         23 . The system of  claim 19 , wherein a fastening element is inserted through the tapered hole.