Systems and methods for promoting sacroiliac joint fusion
Embodiments are directed to fusion implants, insertion instruments, and methods of using the same for implanting one or more fusion implants across a sacroiliac joint and into an ilium and sacrum for fusing the sacroiliac joint. In some cases, fusion-promoting material may be inserted in the fusion implant for further promoting fusion across the sacroiliac joint. In some cases, neurophysiologic monitoring may be performed as the fusion implants are placed across the sacroiliac joint.
1. A system for fusing a sacroiliac joint, comprising: a fusion implant, the fusion implant comprising:
a main body having a longitudinal axis and a length extending from a proximal end to a distal end and being dimensioned for placement across a sacroiliac joint, the main body having a plurality of anti-migration features disposed along an entire length of the main body;
a guide hole extending through along the longitudinal axis of the main body;
a plurality of fusion apertures located along a substantial portion of the length of the main body, each of the plurality of fusion apertures extending through sides of the main body and intersecting the guide hole such that the plurality of fusion apertures are configured to allow a plurality of boney bridges to form across the fusion implant, and wherein at least one of the plurality of fusion apertures extends into the main body through at least one of the plurality of anti-migration features; and
a coupling head disposed at the proximal end of the main body, the coupling head having anti-rotation features on its external surface which allow for bone to grow into the features and secure the implant in position; and an insertion device configured to attach to the coupling head for implanting the fusion implant across a sacroiliac joint.
2. The system of claim 1 , wherein each of the plurality of fusion apertures comprises an elongated shape.
3. The system of claim 2 , wherein the elongated shape of the plurality of fusion apertures is disposed diagonal with respect to the longitudinal axis of the main body.
4. The system of claim 3 , wherein each of the plurality of fusion apertures extends through at least two anti-migration features.
5. The system of claim 1 , the fusion implant further comprising a tapered nose disposed at a distal end of the fusion implant, the tapered nose configured to assist in the insertion of the fusion implant into a bone.
6. The system of claim 5 wherein the tapered nose is dimensioned such that a surface of the tapered nose forms an angle between 30 to 70 degrees relative to the longitudinal axis of the fusion implant.
7. The system of claim 1 , wherein the at least one of the plurality of fusion apertures that extends into the main body through at least one of the plurality of anti-migration features is configured to receive one of the plurality of boney bridges therethrough, securing the fusion implant in place.
8. The system of claim 1 , wherein the insertion device further comprises an inner shaft coupled to an outer shaft, where the inner shaft can rotate and travel along a longitudinal axis of the insertion device independently of the outer shaft.
9. The system of claim 1 , wherein the insertion device further comprises a pusher for pushing fusion-promoting material into the fusion implant.
10. The system of claim 1 , the insertion device comprising:
an inner shaft having a proximal end and a distal end, with the distal end having at least one thread for engaging the coupling head of the fusion implant;
an outer shaft having a proximal end and a distal end, with the distal end having at least one counter-torque feature for engaging a counter-torque feature of the fusion implant; and
a pusher having a proximal and a distal end, with the distal end including a head for pushing fusion-promoting material into the fusion implant.
11. The system of claim 10 , wherein the inner shaft includes a lumen that extends along an entire length of the inner shaft and which is sized and shaped to allow the head of the pusher to travel along a length of the lumen.
12. The system of claim 10 , wherein the counter-torque feature of the outer shaft includes extensions extending from the distal end of the outer shaft and which mate with indentations along the fusion implant for providing counter-torque.
13. The system of claim 10 , wherein the pusher includes a blunted feature along the proximal end of the pusher.
14. The system of claim 10 , wherein the pusher includes a guide lumen that extends along a length of the pusher.
15. A system for fusing a sacroiliac joint, comprising: a fusion implant comprising:
a main body having a plurality of anti-migration features extending along an entire length thereof, each anti-migration feature including a ridge extending radially from an exterior of the main body;
a through-hole extending along an entirety of a longitudinal axis of the main body; a plurality of fusion apertures extending through the main body and intersecting the through-hole, the plurality of fusion apertures configured to allow a plurality of bony bridges to be formed across the fusion implant within the plurality of fusion apertures; and
a coupling head disposed at a proximal end of the main body, the coupling head having anti-rotation features on its external surface which allow for bone to grow into the features and secure the implant in position.