Drilling/milling guide and keel cut preparation system
View Patent ↗An instrument system, associated milling or drilling guide and method include use of a trial implant of a size corresponding to an actual implant for the intervertebral space, with a milling guide mounted on the trial implant. The system also includes a cutting tool which is used to form a cutout in an adjacent vertebra.
1. An instrument system for preparing an intervertebral space, the instrument system comprising:
a trial head having a first vertebral-body facing surface and a second vertebral-body facing surface spaced from the superior surface along a first direction, the trial head defining a height from the first vertebral-body facing surface to the second vertebral-body facing surface that is sized to be received in the intervertebral space; and
a milling guide configured to be supported relative to the trial head, the milling guide including:
a milling guide body defining a proximal end and a distal end that is spaced from the proximal end along a distal direction, perpendicular to the first direction; and
a pivot element pivotally coupled to the milling guide body at a pivot axis, the pivot element being elongate as it extends in the distal direction with respect to the pivot axis and defining a channel that extends through the pivot element such that the channel is configured to at least partially receive a cutting tool to form a cutout in a vertebra;
wherein the pivot axis is translatably fixed relative to both the milling guide body and the pivot element with respect to the distal direction, and a proximal direction opposite the distal direction, and the pivot element is configured to pivot about the pivot axis relative to the milling guide body when the milling guide is supported relative to the trial head to thereby form the cutout in the vertebra.
2. The instrument system of claim 1 , further comprising the cutting tool, wherein the cutting tool is configured to create a channel in a vertebra when the cutting tool extends through the pivot element and the pivot element pivots about the pivot axis.
3. The instrument system of claim 2 , wherein the cutting tool comprises a cutting head which is conically shaped.
4. The instrument system of claim 2 , wherein at least one of the first vertebral-body facing surface and second vertebral-body facing surface of the trial head defines a longitudinal groove that is configured to receive a cutting head of the cutting tool.
5. The instrument system of claim 4 , wherein the longitudinal groove is larger than the cutting head to provide a repository for cut vertebra.
6. The instrument system of claim 2 , wherein the cutting tool defines a stop that abuts the milling guide when the cutting tool is fully inserted into the pivot element so as to limit the insertion depth of the cutting tool.
7. The instrument system of claim 1 , wherein the pivot element has a proximal end and a distal end spaced from the proximal end along the distal direction, and the pivot element is pivotally coupled to the milling guide body at the proximal end of the pivot element.
8. The instrument system of claim 1 , further comprising a support member configured to be connected between the trial head and the milling guide.
9. The instrument system of claim 8 , wherein the support member is configured to carry the trial head as the trial head is inserted into the intervertebral space.
10. The instrument system of claim 9 , wherein the support member comprises a shaft.
11. The instrument system of claim 1 , wherein the pivot element is configured to pivot about the pivot axis relative to the milling guide body so as to move relative to the trial head when the milling guide is supported relative to the trial head.
12. The instrument system of claim 1 , wherein the pivot axis extends in a second direction that is substantially perpendicular to both the first and distal directions.
13. The instrument system of claim 12 , further comprising a pin that extends from the milling guide body to the pivot element in the second direction along the pivot axis so as to pivotally couple the pivot element to the milling guide body.
14. An instrument system for preparing an intervertebral space, the instrument system comprising:
a trial head having a first vertebral-body facing surface and a second vertebral-body facing surface spaced from the superior surface along a first direction, the trial head defining a height the first vertebral-body facing surface to the second vertebral-body facing surface that is sized to be received in the intervertebral space;
a milling guide configured to be supported relative to the trial head, the milling guide including:
a milling guide body defining a proximal end and a distal end that is spaced from the proximal end along a distal direction, perpendicular to the first direction; and
a pivot element pivotally coupled to the milling guide body at a pivot axis, the pivot element being elongate as it extends in the distal direction with respect to the pivot axis and defining a channel that extends through the pivot element; and
a cutting tool configured to be at least partially inserted through the channel while the pivot element is coupled to the milling guide body, wherein the cutting tool is configured to create a channel in a vertebra when the cutting tool extends through the pivot element and the pivot element pivots about the pivot axis relative to the milling guide body.
15. The instrument system of claim 14 , wherein the cutting tool comprises a conically shaped cutting head.
16. The instrument system of claim 14 , wherein the cutting tool defines a stop that abuts the milling guide when the cutting tool is fully inserted into the pivot element so as to limit the insertion depth of the cutting tool.
17. An kit for preparing an intervertebral space the kit comprising:
a plurality of trial heads, each trial head having a respective first vertebral-body facing surface and a respective second vertebral-body facing surface spaced from the superior surface along a first direction, and each trial head defining a different height from its respective first vertebral-body facing surface to its respective second vertebral-body facing surface;
a milling guide configured to be supported relative to each of the trial heads, the milling guide including:
a milling guide body defining a proximal end and a distal end that is spaced from the proximal end along a distal direction, perpendicular to the first direction; and
a pivot element coupled to the milling guide body at a pivot axis such that the pivot element pivots about the pivot axis and is translationally fixed relative to the milling guide body with respect to the distal direction and a proximal direction opposite the distal direction, the pivot element being elongate and defining a channel that extends through the pivot element such that the channel is configured to at least partially receive a cutting tool to form a cutout in a vertebra,
wherein the pivot element is configured to pivot about the pivot axis relative to the milling guide body so as to move relative to a select one of the trial heads when the milling guide is supported relative to the select one of the trial heads to thereby form the cutout in the vertebra.
18. The instrument system of claim 17 , wherein at least one of the first vertebral-body facing surface and second vertebral-body facing surface of the trial head defines a longitudinal groove that is configured to receive a cutting head of the cutting tool.
19. The instrument system of claim 17 , further comprising a support member configured to be connected between a select one of the trial heads and the milling guide.
20. The instrument system of claim 19 , wherein the support member is configured to carry the select one of the trial heads as the select one of the trial heads is inserted into the intervertebral space.