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.

Bone structure coupling devices and methods are provided herein. An example method includes positioning a tubular retraction guide body into a patient, the tubular retraction guide body having two prongs that are positioned in a joint between two adjacent bone structures, creating a hemispherical groove on each of the two adjacent bone structures using a drill bit passed through the tubular retraction guide body, incising out the hemispherical grooves with a broach passed through the tubular retraction guide body, and inserting a graft body having a generally rectangular cross sectional area into the angular grooves to couple the two adjacent bone structures together.

Threaded sacro-iliac joint stabilization (e.g., fusion, fixation) implants and methods of implantation and manufacture. Some implants include a threaded distal region, an optionally threaded central region, and an optionally threaded proximal region. The distal, central, and proximal regions have lengths such that when the implant is laterally implanted across a SI joint, the distal region can be positioned in a sacrum, the central region can be positioned across an SI-joint, and the proximal region can be positioned in an ilium.

Systems, apparatuses and methods for bone fusion are disclosed. In particular, a fixation screw assembly is provided that comprises a bone engagement portion including a shaft and a head member. The assembly also includes a flexible washer member that can be operably attached and secured around the head member of the bone engagement portion. The washer member is polyaxial relative to the bone engagement portion, such that it can assume a variety of angles. The washer member can help prevent back out of the bone engagement portion when the bone engagement portion is implanted into a bone member. The design of the fixation screw assembly can be used in different fusion procedures, including fusion of the sacroiliac joint.

An allograft implant for fusing a sacroiliac joint, the allograft implant having a body with two opposing faces. A graft window is disposed between the two opposing faces, the graft window providing passage through the body between the two opposing faces. A portion of the body located between the graft window and each of the sides defines a wall such that the wall maintains a minimum thickness in a range of about 17% to about 20% of the width of the body.

Implants for the fusion or fixation of two bone segments are described. For example, the implants can be used for the fusion or fixation of the sacroiliac joint. The implants can have a matrix structure, have a rectilinear cross-sectional area, and have a curvature.

Various embodiments of a coupler and an intradiscal implant for alignment and fusion of the sacroiliac joint are described herein.

A guidewire system for spine surgeries includes a first guidewire portion having an elongate first guidewire body with a distal end and a proximal end. A threaded male fastener at the distal end of the first guidewire body is configured to fasten to a vertebra of a spine of a subject and a threaded female coupler at the proximal end of the first guidewire body defines a threaded opening. The guidewire system includes a second guidewire portion having an elongate second guidewire body with a distal end and a proximal end. A threaded male coupler at the distal end of the second guidewire body is configured to thread into the threaded female coupler of the first guidewire portion to fasten the second guidewire portion to the first guidewire portion to form an elongate guidewire.

A bone fusing implant device includes an elongated body extending along a longitudinal direction and having a star-shaped cross-section. The elongated body includes a central through-opening extending through the elongated body's center along the longitudinal direction and an outer surface with alternating elongated ridges and slit openings extending along the longitudinal direction. The outer surface is coated with bone growth enhancing additives.

An embodiment includes a sacroiliac joint bone anchor system comprising: a bone anchor including an outer surface and an inner surface; wherein (a)(i) the outer surface includes a proximal third, a middle third, and a distal third, (a)(ii) the middle third of the outer surface includes at least one aperture that couples the outer surface to the inner surface; (a)(iii) the proximal third of the outer surface includes proximal threads, and (a)(iv) the distal third of the outer surface includes distal threads; wherein (b)(i) the bone anchor is cannulated, (b)(ii) a channel is located on the inner surface, (b)(iii) the channel extends from a proximal third of the inner surface to a distal third of the inner surface, and (b)(iv) the channel provides at least one half a rotation about a long axis of the bone anchor.