Kit of spine gauge blocks and a tool assembly

Abstract

An assembly of a gauge block and tool for determining the size and shape of space between two adjacent vertebrae. There are a plurality of gauge blocks of different sizes and shapes for determining the vertebral space for subsequent insertion of a permanent artificial spinal disc. As such, a kit with vertebral gauge blocks is disclosed. A method of providing the assembly is also included herein.

Description

RELATED APPLICATIONS

This Divisional Application claims priority to U.S. application Ser. No. 10/783,430, filed Feb. 23, 2004, the contents of which is incorporated herein by reference.

FIELD OF THE INVENTION

A kit of spine of spine gauge blocks and a tool whereby the distance between two adjacent surfaces in two adjacent vertebrae can be determined. The surgical approach can be accomplished while moving the gauge block into the patient's body without interference from the patient's body parts, such as the patient's aorta, for instance. There can be two different paths of entry into the patient's body, to avoid the body parts. Also included are a method of presenting the assembly of the spinal gauge blocks and the tool and of achieving the mentioned procedure.

BACKGROUND OF THE INVENTION

Human spines are commonly prepared for implanting an artificial disc between two adjacent vertebrae which present two adjacent surfaces facing each other along the spinal column. The procedure of implanting an artificial disc is performed by a surgeon when a person's natural disc is defective. There may be a ruptured or herniated natural disc, and thus the need for the surgical repair consisting of the replacement of the natural disc with an artificial disc. The artificial disc may be man-made and of metal or plastic materials, and its size and shape should be that of the natural disc where the surgery is to restore the spine to a healthy condition.

The space between the two adjacent vertebrae surfaces which face each other along the spinal column is first cleaned by the surgeon and the remaining cleaned space is then to be gauged to determine the height and the angulation between those two surfaces. That is preparatory for the insertion of an artificial disc implant which should snugly occupy the space for desired spinal supportive action.

It is an object of this invention to accurately and efficiently determine the size of that cleaned spaced so that a most appropriate size and shape of artificial implant can be positioned between the two vertebrae. Because this disc implant surgery is approached from the anterior of the patient's torso, it is necessary to negotiate the patient's body parts which normally lie on the path extending from the anterior to the spine. For instance, for the site between the patient's fifth lumbar vertebra and the adjacent first sacral vertebra that site can be approached along a frontal line from the anterior to that site. Therefore, one tool and trial or gauge block arrangement can be employed for accessing that site.

However, other sites along the spine, and the lordotic ones are the ones under consideration herein, that is, those along both the lumbar and cervical spinal lengths, may require an approach which is laterally offset from the full anterior frontal approach mentioned above. That offset is with regard to the approaches, except the one mentioned above, where the patient's aorta is on the access line between the anterior and the spine site.

To accomplish the aforementioned two approaches, this invention provides for two lines between the anterior and the vertebrae sites. This provides for the accurate gauging of the site space height and the tapered angulation between the vertebrae surfaces as they exist on the lordotic vertebrae. A kit of a plurality of different sizes and shapes of gauge blocks or trials, and one tool which can fit all the blocks can be provided to achieve the implanting of the variety of implant sizes required for optimum restoration of the lordosis of the spine. In the ultimate, there can be a first plurality of blocks which have only one maximum height but which have different angulations or tapers for determining the lordotic angulation of various first sites which are at that one height. Then there can also be a second plurality of blocks at a second height and with their different angulations or tapers for determining the lordotic angulation for various second sites different from the first various sites. Additional pluralities of blocks can also be provided.

The gauge blocks or trials of this invention are provided in kit arrangement in that they are in a plurality and are selected by the surgeon for individual use in determining the size of the vertebrae space in which an artificial implant is to be placed for permanent installation. Thus, the surgeon can select the optimum height and shape or taper of the implant after the surgeon has explored the site by sensing with the gauge block. In those instances, the sites are of the tapered lordotic shape, and therefore they are in the lumbar and cervical lengths of the spine. That shape is such that the space is higher at the anterior side of the spine, compared to the posterior side, that is, it is tapered down to the rear of the spine. According to the patient, the height and taper of any particular site can differ from that of another patient. So, for instance, a collection of say six blocks, all at a maximum height of say 11 mm at the highest location of the taper, can each have their own individual angulation of taper, such as 4, 5, 6, 7, 8, and 9 degrees. Other heights and angulations can also be provided to match the variety of vertebrae spacing and patients.

Further, each block can be arranged for accommodating the two angularly related anterior approaches, thus the kit is doubled in its versatility for the various approaches. Still, each gauge block can be inverted for spinal approaches from either lateral side of the patient.

Both the assembly of the blocks with the tool and the method of producing and applying same are disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a gauge block of this invention.

FIG. 2 is a side elevation view of the block of FIG. 1, and showing a fragment of the tool attached.

FIG. 3 is a perspective view of the block of FIG. 1, but on a reduced scale.

FIG. 4 is a side elevation view of FIG. 3, and showing fragments of two adjacent vertebrae.

FIG. 5 is a side elevation view of FIG. 3.

FIG. 6 is a section view along a plane designated by the line 6-6 on FIG. 5.

FIG. 7 is a side elevation view of the tool used with the block shown herein.

FIG. 8 is a section view along a plane designated by the line 8-8 on FIG. 7.

FIG. 9 is a top plan view of the tool shown in FIG. 7.

FIG. 10 is an end elevation view of FIG. 9.

FIG. 11 is an enlarged perspective view of the right end of the tool shown in FIG. 9.

FIG. 12 is an enlarged perspective view of an interior part of the tool shown in FIG. 8.

FIG. 13 is an enlarged section view of a part of the tool shown in FIG. 8.

FIG. 14 is a diagrammatic left side view of person and showing the human spinal column with its five extended segments.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT AND METHOD

FIG. 1 shows a gauge block 10 of this invention, and it is seen, as in FIG. 6, as having a cylindrical configuration in a top view thereof. There are two spaced-apart and planar surfaces 11 and 12, such as shown in FIG. 2 where the block 10 is more clearly shown as having a tapered shape. The block 10 also has an encompassing peripheral surface 13 extending completely around the side of the block 10 and between the two surfaces 10 and 11. In the configuration of the block 10 as shown herein, the surface 13 is an endless side of the block and is circular in its shape. The block 10 is preferably a solid piece. The surfaces 11 and 12 are planar and completely smooth by being free of any projections.

Being of a taper or wedge shape, a location on the block at 14 presents a height which is greater than the height at a location designated 16. Those two locations 14 and 16 are therefore respectively at the maximum and minimum heights of the block 10, and they are on diametrical opposite sides of the block 10. An indicia, in the shown form of an arrow 17, is affixed on the block surfaces 11 and 12, such as shown on the surface 11. There is an arrow head 18 which is pointing to the location of the maximum height 14. The arrow has a stem portion 19 which is aligned with the tapered shape of the block 10. The surface 12 of the block 10 can also have indicia, such as indicia 17, aligned with the taper. Of course, other indicia could be applied to indicate the orientation of the taper of the block 10.

FIGS. 1, 3, 5, and 6 also show there is a groove or relief 21 in the surface 13, and it extends in the height direction to be spaced from the two surfaces 11 and 12. That is, there are lips 22 and 23 of the wall or surface 13 intervening between the surfaces 11 and 12, respectively. The relief terminates in a blind wall 24. Thus, there is a counter-sunk portion in the side surface 13 of the block 10 and that is one portion of a tongue-and-groove connection.

The wall 24 has two holes 26 and 27 extending therein, and they are shown as threaded holes with respective central axes 28 and 29 directed to the central longitudinal axis 31 of the block 10, all as best shown in FIGS. 5 and 6. The hole 26 is aligned with the taper indicia 17 to be on the same upright plane therewith. The hole 27 is angulated relative to the indicia 17, and it is thus angulated to the orientation of the taper of the block 10. However, both holes 26 and 27 extend radially, and that is each is axially aligned, with the central axis 31 of the block 10, as shown in FIG. 6.

A tool 32, fully described later, can be releasably connected to the block 10 by threading into either of the two holes 26 or 27, at the election of the surgeon. With the two holes 26 and 27, the surgeon can approach the patient's spine from the patient's anterior. By making the elected threaded connection in the hole 26 there can be a frontal approach, and by using the hole 27 there can be an oblique or angulated approach. In both approaches, the smaller height at 16 will be in the desired leading position in moving toward the spine. The election of the approach to be employed will be determined by the clearance or obstruction presented by parts of the patient's body along a line from the anterior to the spine and according to which vertebra is accessed. Tool 32 extends only with the planes of the surfaces 11 and 12.

FIG. 1 shows the block is marked with the size of 11 mm, and that is the dimension of the maximum height at 14. This invention provides for a plurality of the blocks of the 11 mm height, but each one of that plurality will have a different angulation of the taper. That is, one can be at a four-degree taper, another at a five-degree taper, and so on through series of 11 mm blocks. Then there can be another series of blocks with a different height of say 13 mm, and each of that series can have the various angulations of the tapers mentioned. Of course the surgeon can then select one block and connect it to the tool 32 and present that block to the spine for determining the space size and shape between adjacent vertebrae, as previously and hereinafter mentioned.

FIG. 14 shows a human spine in a person's body, and the usual but different portions along the spinal length are indicated by the shown diagonal lines. Having in mind that the cervical and the lumbar portions are both lordotic, the vertebrae spaced therealong have adjacent surfaces which are angulated relative to each other. That as shown in FIG. 4 which could be the fifth lumbar L-5 and the first sacrum S-1. Those two adjacent vertebrae have adjacent surfaces V-1 and V-2 which face each other, and, as with all vertebrae in the cervical and lumbar portions, the two adjacent surfaces present an inclusive taper in a greatest height toward the patient's anterior and such as the taper is shown by the lines 33 which are aligned with that shown taper orientation.

It will be understood that the space between the two surfaces V-1 and V-2 has been surgically cleared of the patient's natural spinal disc, and that presents a tapered space between those two adjacent surfaces. The selected block 10 can then be inserted into that vertebrae space to thereby gauge the height and angulation of the space, by sliding between the surfaces V-1 and V-2 as a feeler gauge.

FIG. 4 shows the block disposed between the surfaces V-1 and V-2, and it will be understood that the tool 32 can be attached to the block 10. As shown, the block matches the height and the taper of that space so the surgeon will then select a disc implant (not shown) for permanent insertion into that space upon withdrawal of the trial block 10 from that space. As mentioned with regard to FIG. 4, the hole 26 was used to position the block 10 because the frontal straight approach could be employed to access those two vertebrae. For other vertebrae, hole 27 and its angulated approach, could be used to avoid interference from the patient's body parts in the approach to the spine at other vertebrae along the lordotic structure. In all instances, the smaller height 16 of the block 10 which is being used will be the leading side in the approach into the vertebrae space. With the option of the two holes 26 and 27, the selected block 10 can always be moved into the spinal space by direct anterior to posterior movement when at the spine itself.

Because the blocks 10 are symmetrical and invertible about their respective horizontal planes as viewed in FIGS. 2, 4, and 5, and are therefore reversed when inverted, the approach with the use of the oblique hole 27 can be from either the leftward or rightward side of the patient.

The tool 32 is shown to be elongated and it has a central axis along the section line of FIG. 7. There is a handle 36 shown to be threadedly connected to a two-part sleeve 37 which extends along the tool axis. A shaft 38 is rotatable within the sleeve 37 and there is a shaft threaded end 39 for connecting to a selected one of the blocks 10. Also, there is the inter-locking connection between the sleeve 37 and the relief 24 of each block 10 by virtue of the flat extension 41, as best seen in FIG. 11 which fits into the relief 24. In that arrangement, the block 10 cannot rotate about the longitudinal axis and it can therefore be firmly placed relative to the vertebrae, as desired.

The shaft 38 rotates within the sleeve 37 to thereby be threadedly connected to a selected one of the blocks 10, as shown in FIG. 2. Thus the tool 32 at its connection location with the block 10 does not extend beyond the planes of the block surfaces 11 and 12, so the block can be positioned into the vertebrae space without interference from the tool.

A rotator 42 is affixed to the shaft by a set screw 43, and the rotator is rotatable on the sleeve 37 to thereby rotate the shaft 38 and thus threadedly connect the shaft 38 to the block 10 in the selected one of the holes 26 and 27.

The sleeve 37 has distance markings 44 therealong, such as the shown millimeter distances of 20, 30, 40. That shows the surgeon the amount of body penetration of the tool 32.

Each gauge block 10 is preferably circular in its top view, and therefore cylindrical, and each has smooth top and bottom surfaces 11 and 12 which are free of any projections thereon. The holes 22 and 23 have a respective longitudinal axis which is radial to the circular shape, and the holes can be relatively angulated at approximately ten degrees. In the use of either hole 22 and 23, the gauge block will approach the spinal space in the orientation consistent with the lordotic shape of the space, thus the smaller block height will enter the space as a leading edge, in keeping with the lordosis of the patient. The line 17 can be labeled “straight approach” or “frontal approach” or like notation to indicate that alignment with the orientation of the taper.

So there are a plurality of blocks 10 of different heights and tapered shapes, and one tool can be provided to connect with each chosen block. After the correct size of block is inserted to determine the vertebrae space, the block and tool are withdrawn and the permanent implant of the size and shape of the block which fit the space can be installed in place of that gauge block. The lordotic angle, such as shown by the lines 33 and which can be at an angulation of four or six or eight degrees, or the like number.

In the above description, the method of providing the assembly is also disclosed herein. Also, this is the description of the required preferred embodiment, and changes could be made in the described assembly and still be within the scope of the claiming of this invention.

Claims

1. A method for determining a distance between two adjacent spinal vertebrae comprising the steps of:

selecting a spinal gauge block having a predefined height from a plurality of spinal gauge blocks;

inserting the selected spinal gauge block within a space between the two adjacent spinal vertebrae;

determining whether the predefined height of the selected spinal gauge block sufficiently occupies the space between the two adjacent spinal vertebrae for a desired spinal supportive action; and

removing the selected spinal gauge block from the space between the two adjacent spinal vertebrae.

2. The method of claim 1, wherein the steps of inserting and removing the selected spinal gauge block comprise connecting an elongate tool to the selected spinal gauge block and using the elongate tool for inserting and removing the selected spinal gauge block.

3. The method of claim 2, wherein the step of connecting the elongate tool is performed by threading a portion of the elongate tool to the selected spinal gauge block at an angle with respect to a longitudinal axis of the selected spinal gauge block.

4. The method of claim 2, wherein the step of inserting the selected spinal gauge block is completed by inserting the elongate tool at an angle with respect to an anterior position of a spine.

5. A method for determining the distance and angulation between two adjacent spinal vertebrae comprising the steps of:

selecting a spinal gauge block having a predefined height and angulation from a plurality of spinal gauge blocks;

inserting the selected spinal gauge block within a space between the two adjacent spinal vertebrae;

determining whether the predefined height and angulation of the selected spinal gauge block sufficiently occupies the space between the two adjacent spinal vertebrae for a desired spinal supportive action; and

removing the selected spinal gauge block from the space between the two adjacent spinal vertebrae.

6. The method of claim 5, wherein the steps of inserting and removing the selected spinal gauge block comprise connecting an elongate tool to the selected spinal gauge block and using the elongate tool to insert and remove the selected spinal gauge block.

7. The method of claim 6, wherein the step of connecting the elongate tool is performed by threading a portion of the elongate tool to the selected spinal gauge block at an angle with respect to a longitudinal axis of the selected spinal gauge block.

8. The method of claim 6, wherein the step of inserting the selected spinal gauge block is completed by inserting the elongate tool at an angle with respect to an anterior position of a spine.

9. A method for gauging the space between two adjacent surfaces on two adjacent vertebrae comprising the steps of:

providing a kit including a plurality of spinal gauge blocks with each spinal gauge block having a direction of taper and being of different sizes from each other, the kit further including an elongate tool individually connectable to each of said spinal gauge blocks, the elongate tool having an elongated axis;

providing connection accommodations on each of said spinal gauge blocks for connection with said elongate tool at respective angles relative to the direction of taper of said spinal gauge blocks; and

alternately connecting said elongate tool with said connection accommodations for positioning said tool elongated axis in separate locations while placing one of said spinal gauge blocks between said two adjacent surfaces.

10. The method of claim 9, further including the step of providing distance markings along said elongate tool and relative to the position of said spinal gauge block.

11. The method of claim 9, further including the step of providing said spinal gauge blocks with cylindrical shapes on an axis extending transverse to the direction of taper.

12. The method of claim 11, wherein the step of providing connection accommodations on each of said spinal gauge blocks comprises providing a first connection accommodation with a first axis and a second connection accommodation with a second axis, wherein the first axis is parallel to the direction of the taper of said spinal gauge block and the second axis extends transversely to the direction of taper of said spinal gauge block.

13. The method of claim 12, further including the step of threadedly connecting said elongate tool separately to selected ones of said connection accommodations.

14. A method for gauging the dimensions of a space between two adjacent spinal vertebrae, the method comprising the steps of:

selecting a spinal gauge block having an upper block surface and a lower block surface, the upper and lower block surfaces extending in a non-parallel manner to form a height and a taper angle;

inserting the spinal gauge block into the space from a predetermined approach angle; and

confirming that the height and taper angle of the gauge block conform to the lordotic distance and angulation of vertebral surfaces that define the space.

15. The method of claim 14, wherein the step of inserting the spinal gauge block into the space from a predetermined approach angle comprises connecting an elongate tool to the spinal gauge block and using the elongate tool for inserting the selected spinal gauge block.

16. The method of claim 14, wherein the predetermined approach angle lies in the anterior-posterior direction.

17. The method of claim 14, wherein the predetermined approach angle is oblique to the anterior-posterior direction.

18. The method of claim 14, wherein the step of selecting a spinal gauge block comprises selecting said spinal gauge block from a plurality of spinal gauge blocks, each having a different height.

19. The method of claim 14, wherein the step of selecting a spinal gauge block comprises selecting said spinal gauge block from a plurality of spinal gauge blocks, each having a different taper angle.

20. The method of claim 14, comprising the step of comparing the dimensions and taper angle of the selected spinal gauge block with the dimensions and taper of an artificial disc implant.