Method and cut guide for biplanar wedge osteotomy
A wedge osteotomy method inserts a first wire into a first bone of the foot, distal from tissue to be removed. A second wire is inserted into a second bone, so the tissue to be removed is distal from the second wire. A cut guide is pivoted about the first wire, until a first axis of the cut guide is parallel with a longitudinal axis of the first metatarsal. The cut guide has a slot perpendicular to the first axis for guiding a cutter to cut bone, while the first axis is aligned with the longitudinal axis of the first metatarsal. The cut guide is then pivoted about the second wire, until the first axis is aligned with the longitudinal axis of the talus, and bone is cut through the slot, to form a second planar cut into or through bone material.
1. A method for bi-planar wedge osteotomy of a foot, comprising the steps of:
(a) inserting a first wire at least into a first bone of the foot, so that the first wire is distal from tissue to be removed;
(b) inserting a second wire into a second bone of the foot, so that the tissue to be removed is distal from the second wire;
(c) pivoting a cut guide about the first wire, until a first axis of the cut guide is parallel with a longitudinal axis of a first metatarsal of the foot, the cut guide having a slot perpendicular to the first axis of the cut guide for guiding a cutter;
(d) cutting bone through the slot while the first axis of the cut guide is aligned with the longitudinal axis of the first metatarsal;
(e) pivoting the cut guide about the second wire, until the first axis of the cut guide is aligned with a longitudinal axis of a talus; and
(f) cutting bone through the slot while the first axis of the cut guide is aligned with the longitudinal axis of the talus, to form a second planar cut into or through bone material.
2. The method of claim 1 , wherein the cut guide has a row of holes located parallel to the slot, the method further comprising:
placing one of the row of holes over the first wire, prior to step (c); and
placing the same one of the row of holes or a different one of the row of holes over the second wire, prior to step (e).
3. The method of claim 2 , further comprising:
fixing the cut guide to the first bone, by inserting a third wire through another one of the row of holes before step (d); and
fixing the cut guide to the second bone, by inserting a fourth wire through another one of the row of holes before step (f).
4. The method of claim 1 , further comprising viewing a radiopaque marker of the cut guide by fluoroscopy while pivoting the cut guide about the first wire and while pivoting the cut guide about the second wire, the radiopaque marker aligned with the first axis of the cut guide.
5. The method of claim 4 , wherein the radiopaque marker is an elongated metal member, and the method includes inserting the elongated metal member through an alignment opening in the cut guide before the step of viewing.
6. The method of claim 5 , wherein the elongated metal member slidably or threadably engages the alignment opening.
7. The method of claim 1 , wherein step (d) cuts completely through the foot along a first plane, and step (f) cuts completely through the foot along a second plane different from the first plane, further comprising attaching an implant to the first bone and the second bone.
8. The method of claim 7 , wherein the foot has a Meary's angle of greater than 10 degrees before step (d), and the foot has a Meary's angle of less than 4 degrees after the step of attaching.
9. The method of claim 1 , wherein step (d) cuts completely through the foot along a first plane, and step (f) cuts completely through the foot along a second plane parallel to the first plane, further comprising attaching an implant to the first bone and the second bone.
10. The method of claim 1 , wherein:
steps (c) through (f) are performed while the cut guide is on a lateral side of the foot, and
an apex of cuts made in steps (d) and (f) is in a range between the first metatarsal and the fourth metatarsal, the method further comprising:
removing a wedge of bone between the cuts made in steps (d) and (f); and
inserting a wedge of a porous titanium matrix material between the cuts after the step of removing.