Joint fusion instrumentation and methods

A system for fusing a joint between a first bone portion and a second bone portion, the system comprising:

• a guide wire having a distal end and proximal end;
• a cannula having a distal end and proximal end, and a cannula bore extending therebetween, the cannula bore insertable over the guide wire, the cannula bore defining a cannula central longitudinal axis;
• a sleeve having a distal end and a proximal end and a sleeve bore extending therebetween, the sleeve at least partially receivable in the bore of the cannula and adjustably engageable with the cannula;
• an adjustment mechanism, wherein actuation of the adjustment mechanism when the sleeve is engaged with the cannula varies the length between the sleeve proximal end and the cannula distal end along a continuum;
• a cutting instrument actuable to excise a cavity in the joint, the cutting instrument comprising a handle and a blade assembly extending distally from the handle, wherein the blade assembly comprises a blade body having a proximal end and a distal end and first and second opposing sides extending therebetween, the first side having a first cutting edge, the cutting instrument having an instrument cutting radius;
• wherein the blade assembly is movable between a retracted configuration and an extended configuration, wherein the instrument cutting radius in the retracted configuration is less than instrument cutting radius in the extended configuration;
• a graft insertion instrument at least partially receivable in the bore of the cannula;
• an implant insertion instrument at least partially receivable in the bore of the cannula;
• and
• an implant having a first end and a second end and a bone engagement portion, wherein the implant is sized to pass through the cannula bore and engage the first and second bone portions to fuse the joint.

A method for fusing a joint between a first bone portion and a second bone portion, the method comprising:

• inserting an access cannula toward the joint, the access cannula having a distal end and a proximal end and a cannula bore extending therebetween;
• affixing the distal end of the access cannula to the first bone portion adjacent the joint, the bore of the access cannula providing access to the first bone portion;
• inserting a sleeve at least partially into the access cannula bore, the sleeve having a distal end and a proximal end and a sleeve bore extending therebetween;
• inserting a cutting instrument to extend through the sleeve bore toward the joint, the cutting instrument having a longitudinal axis and comprising a handle, an actuation mechanism, and a blade assembly extending distally from the handle;
• wherein the blade assembly comprises a blade body having a proximal end, a distal end and first and second opposing sides extending therebetween, the first side having a first curved cutting edge;
• actuating the actuation mechanism to move the blade assembly from a retracted configuration in which the blade body extends along the longitudinal axis to an extended configuration in which the blade body is projected away from the longitudinal device axis;
• rotating the cutting instrument about the longitudinal axis to urge the blade body first curved cutting edge to excise a cavity in the joint;
• inserting a fusion device through the cannula bore and across the joint, the implant having a first end and a second end and a bone engagement portion, the fusion device crossing the cavity and the joint;
• and
• engaging the fusion device to the first bone portion and the second bone portion.