Freeform tri-planar osteotomy guide and method
Systems and methods for performing an osteotomy are presented. Examples include forming a fusion osteotomy at a metatarsocuneiform joint of the first ray of a human foot.
1. A method of performing an osteotomy between a metatarsus and a cuneiform defining a metatarsocuneiform joint of a human foot, the method comprising:
positioning an osteotomy guide such that a joint alignment feature of the osteotomy guide is aligned with the metatarsocuneiform joint;
securing the osteotomy guide to at least one of the metatarsus and the cuneiform;
with a first guide feature of the osteotomy guide, guiding motion of a first cutter to remove part of the metatarsus, wherein the first guide feature is spaced apart from the joint alignment feature on the osteotomy guide; and
promoting fusion between the metatarsus and the cuneiform, wherein promoting the fusion comprises fixation with one or more pins, plates, screws, or rods.
2. The method of claim 1 , further comprising, after guiding the motion of the first cutter to remove the part of the metatarsus:
rotating the osteotomy guide from a first operative position to a second operative position relative to the metatarsocuneiform joint; and
guiding motion of the first cutter or a second cutter to remove part of the cuneiform prior to promoting the fusion.
3. The method of claim 1 , wherein rotating the osteotomy guide from a first operative position to a second operative position relative to the metatarsocuneiform joint comprises rotating the osteotomy guide about an axis perpendicular to a lengthwise metatarsal axis of the metatarsal.
4. The method of claim 1 , wherein securing the osteotomy guide to at least one of the metatarsus and the cuneiform comprises inserting one or more first wires or pins through the osteotomy guide to secure the osteotomy guide to one of the metatarsus and the cuneiform, the method further comprising, after guiding the motion of the first cutter to remove the part of the metatarsus:
securing the osteotomy guide to the other one of the metatarsus and the cuneiform by inserting one or more second wires or pins through the osteotomy guide; and
guiding motion of the first cutter or a second cutter to remove part of the cuneiform prior to promoting the fusion.
5. The method of claim 1 , wherein:
the first guide feature comprises a first slot;
the first cutter comprises a first saw blade; and
guiding the motion of the first cutter with the first guide feature comprises:
inserting the first saw blade through the first slot; and
with the first saw blade in the first slot, forming a first planar cut in the metatarsus.
6. The method of claim 5 , wherein forming the first planar cut in the metatarsus comprises forming the first planar cut proximate the metatarsocuneiform joint to increase mobility between the metatarsus and the cuneiform.
7. The method of claim 1 , further comprising, with a second guide feature of the osteotomy guide, guiding motion of one of the first cutter and a second cutter to remove part of the cuneiform to create a gap between the metatarsus and the cuneiform.
8. The method of claim 7 , further comprising, before guiding motion of the second cutter to remove part of the cuneiform, moving the metatarsus, relative to the cuneiform, from a first relative position to a second relative position.
9. The method of claim 8 , wherein moving the metatarsus, relative to the cuneiform, to the second relative position comprises moving the metatarsus, relative to the cuneiform, to the second relative position after guiding motion of the first cutter to remove part of the metatarsus.
10. The method of claim 7 , further comprising, prior to guiding motion of the first cutter to remove part of the metatarsus, securing the osteotomy guide to the metatarsus.
11. The method of claim 10 , further comprising, prior to securing the osteotomy guide to the metatarsus, positioning the osteotomy guide such that at least one indexing feature of the osteotomy guide abuts a diaphysis of the metatarsus.
12. The method of claim 10 , further comprising, prior to guiding motion of one of the first cutter and the second cutter with the second guide feature, securing the osteotomy guide to the cuneiform.
13. The method of claim 7 , wherein:
positioning the osteotomy guide comprises positioning the osteotomy guide with the metatarsus in a first orientation, relative to the cuneiform; and
promoting the fusion between the metatarsus and the cuneiform further comprises reducing the gap so that a proximal aspect of the metatarsus abuts a distal aspect of the cuneiform and the metatarsus is at a second orientation, different from the first orientation, relative to the cuneiform.
14. The method of claim 7 , wherein promoting the fusion between the metatarsus and the cuneiform comprises inserting an implant into the gap, wherein the implant is configured to permit fusion between the metatarsus and the cuneiform through the implant.
15. The method of claim 7 , wherein positioning an osteotomy guide such that the joint alignment feature is aligned with the metatarsocuneiform joint comprises positioning the osteotomy guide such that the first guide feature and the second guide feature are unobstructed.
16. The method of claim 1 , wherein:
the osteotomy guide comprises:
a first fixation element; and
a second fixation element parallel to the first fixation element; and
the method further comprises:
securing the osteotomy guide to the metatarsus with the first fixation element independently of any additional fixation element oriented nonparallel to the first fixation guide; and
securing the osteotomy guide to the cuneiform with the second fixation element independently of any additional fixation element oriented nonparallel to the second fixation element.
17. The method of claim 16 , wherein:
the osteotomy guide comprises a guide body;
the first fixation element comprises a first hole formed in the guide body, with an axis passing through the metatarsus with the osteotomy guide positioned such that the joint alignment feature is aligned with the metatarsocuneiform joint; and
the second fixation element comprises a second hole formed in the guide body, with an axis passing through the cuneiform with the osteotomy guide positioned such that the joint alignment feature is aligned with the metatarsocuneiform joint.
18. The method of claim 1 , wherein:
the osteotomy guide comprises a one-piece guide body comprising:
a first fixation element; and
a second fixation element; and
the method further comprises:
securing the osteotomy guide to the metatarsus with the first fixation element; and
securing the osteotomy guide to the cuneiform with the second fixation element.
19. The method of claim 1 , wherein:
the osteotomy guide comprises a one-piece guide body comprising the first guide feature and a second guide feature; and
the method further comprises guiding motion of one of the first cutter and a second cutter to remove part of the cuneiform to create a gap between the metatarsus and the cuneiform.
20. The method of claim 1 , further comprising, prior to guiding motion of the first cutter to remove part of the metatarsus, securing the osteotomy guide to a medial aspect of the metatarsocuneiform joint.