Multi-pronged awl for intervertebral body space
View Patent ↗A multi-pronged awl includes a shaft, a handle extending from a first end of the shaft, and a head extending from the shaft at a second end of the shaft opposite the first end. The head includes a housing and prongs mounted in a cavity of the housing. Activation of the handle portion moves the plurality of prongs between a retracted state within the housing and an extended state extending past an edge on a first side of the housing. A method of repairing a damaged disc space between two neighboring vertebrae defining the damaged disc space includes actuating a handle of thee multi-pronged awl to move the prongs from the retracted state to the extended state to contact and penetrate a predetermined distance into the endplate of the first vertebra while a back surface of the head presses against the endplate of the second vertebra.
1 . A multi-pronged awl comprising:
a shaft portion having an axis along a length of the shaft portion;
a handle portion extending from a first end of the shaft portion;
a deployment shaft extending through the shaft portion and engaged at a proximal end with the handle portion, and having a distal end; and
a head portion extending from the shaft portion at a second end of the shaft portion opposite the first end, the head portion comprising:
a housing having an interior cavity into which the distal end of the deployment shaft extends, the housing having opposing first and second sides, at least the first side having at least one through aperture;
a first trolley half and a second trolley half opposing one another in a direction orthogonal to the shaft portion axis and positioned within the housing, the first trolley half positioned adjacent an interior surface of the first side of the housing and the second trolley half positioned adjacent an interior surface of the second side of the housing, each of the first trolley half and the second trolley half including a plurality of threaded bores; and
a plurality of prongs threadedly mounted to at least a portion of the threaded bores within at least the first trolley half;
wherein, in a retracted state, the first trolley half and the second trolley half are in contact with one another along at least a portion of their respective lengths and the plurality of prongs are wholly within the housing, and
wherein activation of the handle portion moves the deployment shaft toward the second end of the shaft portion and between the first trolley half and the second trolley half to push the first trolley half and the second trolley half apart and toward the housing to thereby move the plurality of prongs orthogonal to the shaft portion axis and into an extended state wherein the plurality of prongs are extended through a single common aperture past an edge on the first side of the housing.
2 . The multi-pronged awl of claim 1 , wherein the shaft portion comprises a retainer shaft having a bore and an activation shaft extending into the bore of the retainer shaft along a central axis of the multi-pronged awl.
3 . The multi-pronged awl of claim 2 , wherein the handle portion comprises a handle knob and a retraction knob rotatably screwed into the handle knob along the central axis of the multi-pronged awl.
4 . The multi-pronged awl of claim 1 , wherein the head portion is contoured and sized to be received in an intervertebral body space.
5 . The multi-pronged awl of claim 4 , wherein the head portion further comprises a shim insert removably affixed to a second side of the housing to increase a height of the head portion.
6 . A multi-pronged awl kit comprising:
a multi-pronged awl including:
a shaft portion having an axis along a length of the shaft portion;
a handle portion extending from a first end of the shaft portion;
a deployment shaft extending through the shaft portion and engaged at a proximal end with the handle portion, and having a distal end; and
a head portion extending from the shaft portion at a second end of the shaft portion opposite the first end, the head portion comprising:
a housing having an interior cavity into which the distal end of the deployment shaft extends, the housing having opposing first and second sides, at least the first side having at least one through aperture;
a first trolley half and a second trolley half opposing one another in a direction orthogonal to the shaft portion axis and positioned within the housing, the first trolley half positioned adjacent an interior surface of the first side of the housing and the second trolley half positioned adjacent an interior surface of the second side of the housing, each of the first trolley half and the second trolley half including a plurality of threaded bores; and
a plurality of prongs threadedly mounted to at least a portion of the threaded bores within at least the first trolley half;
wherein, in a retracted state, the first trolley half and the second trolley half are in contact with one another along at least a portion of their respective lengths and the plurality of prongs are wholly within the housing, and
wherein activation of the handle portion moves the deployment shaft toward the second end of the shaft portion and between the first trolley half and the second trolley half to push the first trolley half and the second trolley half apart and toward the housing to thereby move the plurality of prongs orthogonal to the shaft portion axis and into an extended state wherein the plurality of prongs are extended through a single common aperture past an edge on the first side of the housing; and
a plurality of interchangeable shim inserts having different thicknesses for affixing to a second side of the housing to adjust a height of the head portion.
7 . A method of repairing a damaged disc space between a first vertebra and a second vertebra neighboring the first vertebra, the first vertebra and the second vertebra defining the damaged disc space, the method comprising:
actuating the handle of the multi-pronged awl of claim 1 to move the plurality of prongs orthogonal to the shaft portion axis of the multi-pronged awl from the retracted state within the interior cavity in the housing to the extended state extending through the single common aperture past the edge of the housing to contact and penetrate a predetermined distance into a first endplate of the first vertebra while a back surface of the head portion presses against a second endplate of the second vertebra.
8 . The method of claim 7 , further comprising, prior to the actuating, inserting the head portion of the multi-pronged awl into the damaged disc space.
9 . The method of claim 7 , further comprising, prior to the actuating, selecting the head portion of the multi-prong awl to have a predetermined height and a predetermined contour based on a distance between the first endplate and the second endplate, a contour of the first endplate, and a contour of the second endplate.
10 . The method of claim 9 , further comprising, prior to the selecting, determining the distance between the first endplate and the second endplate, the contour of the first endplate, the contour of the second endplate, and a thickness of the first endplate.
11 . The method of claim 10 , further comprising, prior to the selecting, mounting the prongs in the head portion such that in the extended state, the prongs extend a predetermined distance into the first endplate with the back of the head portion positioned against the second endplate based on the determined thickness of the first endplate.
12 . The method of claim 7 , further comprising, after the actuating, actuating the handle to return the prongs to the retracted state and withdrawing the head portion of the multi-pronged awl from the damaged disc space.
13 . The method of claim 7 , wherein the actuating does not crush the first endplate.