SURGICAL REAMER FOR REMOVING BONE

Abstract

There is provided a surgical reamer for removing bone, e.g., to access the spinal canal, the surgical reamer comprising: a shaft extending longitudinally along the length of the surgical reamer; and a cutting section for cutting bone, the cutting section being situated at a distal portion of the shaft, wherein the cutting section is provided at a lateral surface of the shaft so as to extend along part of the circumference of the shaft, and the cutting section extends along less than 50% of the circumference of the shaft. Furthermore, a corresponding set of reamers and a method for removing bone with a surgical reamer are provided.

Claims

1. A surgical reamer for removing bone, the surgical reamer comprising: a shaft extending longitudinally along the length of the surgical reamer; and a cutting section for cutting bone, the cutting section being situated at a distal portion of the shaft, wherein the cutting section is provided at a lateral surface of the shaft so as to extend along part of the circumference of the shaft, and the cutting section extends along less than 50% of the circumference of the shaft.

2. The surgical reamer according to claim 1, further comprising a non-cutting protective tip for protecting nerves, tissue and/or dura from being damaged, wherein the protective tip extends distally of a distal end of the shaft.

3. The surgical reamer according to claim 2, wherein the non-cutting protective tip is cone-shaped.

4. The surgical reamer according to claim 1, wherein the surgical reamer is for removing bone to access the spinal canal.

5. The surgical reamer according to claim 1, wherein the surgical reamer is configured to perform an oscillating rotational movement along the circumferential direction of the shaft.

6. The surgical reamer according to claim 1, wherein the cutting section extends along less than 45% of the circumference of the surgical reamer, preferably between 25% and 45%, particularly preferably 35%.

7. The surgical reamer according to claim 1, wherein the cutting section extends along at least 10%, preferably at least 20%, of the circumference of the surgical reamer.

8. The surgical reamer according to claim 1, wherein the cutting section extends in the longitudinal direction of the shaft over at least 10 mm, preferably between 15 mm and 50 mm.

9. The surgical reamer according to claim 1, wherein, in a cross-section perpendicular to the longitudinal direction of the shaft, the cutting section has the shape of a segment of a circle.

10. The surgical reamer according to claim 1, wherein the cutting section comprises a plurality of blade members, each blade member substantially extending along the longitudinal direction of the shaft.

11. The surgical reamer according to claim 1, wherein the cutting section comprises sharp spots and/or turbine blades and/or sharp edges and/or cutting flutes and/or straight blades.

12. The surgical reamer according to claim 1, wherein the shaft comprises a guide channel extending in the longitudinal direction of the shaft such that a guide wire can be inserted into the guide channel through the shaft.

13. The surgical reamer according to claim 1, wherein the shaft has an outer diameter in the range of 2.0 mm to 10.0 mm.

14. The surgical reamer according to claim 2, wherein the diameter of the protective tip at a proximal end of the protective tip is substantially the same as the diameter of the shaft.

15. The surgical reamer according to claim 2, wherein the diameter of the protective tip at a proximal end of the protective tip is smaller than the diameter of the shaft, preferably by more than 0.1 mm, more preferably by more than 0.5 mm.

16. The surgical reamer according to claim 2, wherein the protective tip is positioned radially inside the cutting section.

17. A set of surgical reamers comprising at least a first surgical reamer and a second surgical reamer according to claim 1, wherein the diameter of the shaft of the second surgical reamer is larger than the diameter of the shaft of the first surgical reamer.

18. A method for removing bone with a surgical reamer according to claim 1, the method comprising the following steps: positioning the surgical reamer at the location at which bone material is to be removed; and performing an oscillating rotational movement of the surgical reamer along the circumferential direction of the shaft, wherein the rotational movement of the surgical reamer oscillates between rotational movement in the clockwise direction and rotational movement in the anticlockwise direction, and in each of the rotational movement in the clockwise direction and the rotational movement in the anticlockwise direction, the surgical reamer rotates by only part of a full turn of the surgical reamer, preferably by 80% or less of a full turn.

19. The method according to claim 18, wherein, after the removal of bone material with the surgical reamer is finished, another surgical reamer according to claim 1, having a shaft with a larger diameter, is positioned at the location at which bone material is to be removed.

20. The method according to claim 18, wherein the surgical reamer is guided to the location at which bone material is to be removed by means of a guide wire, wherein the guide wire is inserted in a guide channel extending in the longitudinal direction of the shaft of the surgical reamer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0070] For a better understanding of the present invention and to see how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:

[0071] FIG. 1 shows a side view of a surgical reamer according to an exemplary embodiment of the present invention;

[0072] FIG. 2 shows a cross sectional view of the surgical reamer according to the exemplary embodiment, taken along lines A-A in FIG. 1;

[0073] FIG. 3 shows an enlarged view of the distal end of the surgical reamer according to the exemplary embodiment of the present invention, as indicated by the encircled area Z in FIG. 1; and

[0074] FIG. 4 shows a bottom view of the surgical reamer according to the exemplary embodiment of the present invention taken from the distal end of the reamer.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0075] FIGS. 1 and 2 show a surgical reamer having a continuous cutting section 1 for cutting bone inside a patient's body, wherein the cutting section 1 is disposed at a distal portion of a shaft 2 shown in FIG. 1. Besides the cutting section 1, the surgical reamer also has a continuous non-cutting section 4 in the remaining circumference of the distal end of the shaft for protecting the surrounding tissue during the removal of bone material. Additionally, the reamer has a protective tip 7 being arranged at a distal portion of the shaft. Further, the shaft has a guide channel which extends along the center of the longitudinal axis of the shaft. Additionally, the surgical reamer of the exemplary embodiment also has a connector 3, for connecting the surgical reamer to a driving system and/or a control, or the like.

[0076] As can be taken from FIG. 1, the cutting section 1 extends along less than 50% (in this exemplary embodiment approximately 25%) of the circumference of the shaft 2 and is arranged at a lateral surface of the shaft 2. The part of the circumference of the shaft 2 which is not covered by the cutting section 1 is covered by the non-cutting section 4, also arranged at the distal end of the shaft 2 of the surgical reamer. This non-cutting section 4 is arranged to protect the tissue in the patient which should be protected from being injured or harmed by the sharp cutting section. Therefore, the surface of the non-cutting section 4 should be designed smooth and even.

[0077] As can be seen from FIG. 3, the cutting section 2 comprises four blades in the cutting section 1 spread around the cutting section with a constant sequence, the blades being configured to cut when the reamer is oscillated in clockwise and anti-clockwise directions over a certain percentage of a full turn. This percentage is dependent on the conditions inside the patient's body, i.e. the surrounding nerves or tissue.

[0078] As is shown in FIG. 4, the four sharp blades have an angle of rifling of 3 to the longitudinal axis, which can be used for cutting and removing bone by reaming along the circumference (the side) of the reamer.

[0079] The non-cutting protective tip 7 extends distally of a distal end of the shaft 2. In this orientation, the protective tip 7 provides protection for the tissue, nerves and/or dura of the patient by extending distally of the distal end of the cutting section. As can be taken from FIGS. 1 and 2, in this exemplary embodiment, the protective tip 7 shows a smaller diameter than the shaft 2. In other embodiments, it may also be feasible that the proximal end of the protective tip 7 has the same diameter as the distal end of the shaft, so that no edges are existent at this position of the shaft. Other shapes of the protective tip 7, such as cylindrical or the like, are also possible without any further limitation.

[0080] As can be taken from FIGS. 1 and 2, the reamer has a cylindrical portion 9 which is arranged between the proximal end of the protective tip 7 and the distal end of the shaft 2 having a smaller diameter than the shaft 2 and the same diameter as the proximal end of the protective tip.

[0081] In general, the surgical reamer can be driven by a control (not shown) for controlling the reamer and a driving mechanism (not shown) for driving the reamer. The control is connected to the surgical reamer by the connector 3. This connector 3 can have a standardized shape or connection standard which allows transferring forces in a circumferential direction. Further, the control and the driving mechanism may allow a movement in a radial or axial movement of the reamer as well.

[0082] Most importantly, the connector 3 is used to transmit rotational forces so as to achieve an oscillating movement of the shaft 2. Thus, removing the bone material by an oscillating movement of the shaft 2 is achievable. That means, the reamer is not moved around the whole circumference, but moves clockwise and anticlockwise by a certain frequency to remove bone material.

[0083] In FIG. 1, the guide channel 5 of the surgical reamer is also shown. The guide channel 5 is a through hole along the center of the longitudinal axis of the shaft for receiving a guide wire (not shown), which is guided through the guide channel. The guide wire can be a thin wire which allows facilitating insertion into the patient's body.

[0084] FIGS. 1 to 4 all show the same reamer of an exemplary embodiment of the invention. Additionally, it is also feasible to use the described reamer in a set of reamers which differ from each other in at least one parameter. That means all reamers have the same general configuration of the invention but differ in one parameter. For example, a set of reamers according to the invention can comprise a plurality of reamers with each reamer of the set of reamers having a different diameter. Furthermore, for example, the set of reamers may also comprise a plurality of reamers having different cutting sections, different blades, or a different amount of blades in the continuous cutting section.

[0085] Apart from the aforementioned exemplary embodiments, which teach the manner in which the invention may be carried into effect, further alternative embodiments are conceivable. In particular, there are a number of variations which are possible, as may be appreciated by those skilled in the art.

[0086] Now, a method for removing bone with a surgical reamer, as described above, is described. First of all, after opening the patient's body, the surgical reamer is guided towards the area, where bone material is to be removed. In an exemplary embodiment of the method, guiding the surgical reamer by a guide wire running through the guide channel 5 of the surgical reamer may be feasible. By this guide wire, it is also achievable to optically check the situation and the surrounding of the area to be cut with an optical system being inserted before the beginning of the insertion of the surgical reamer.

[0087] After the situation inside the patient is checked and the position of the material to be removed and the surrounding tissue and, for example, the position of nerves which should be protected is detected, the surgical reamer can be positioned at the starting position inside the human body.

[0088] In a next step, an oscillating rotational movement of the surgical reamer along the circumferential direction of the shaft is started. Thereby, the force is transmitted via a control and a corresponding driving mechanism (not shown). Thereby, the rotational movement of the surgical reamer oscillates between a rotational movement in the clockwise and a rotational movement in the anticlockwise direction. Thereby, the cutting section 1 of the shaft 2 is in contact with the bone material to be removed and the non-cutting section 4 meanwhile protects the nerves and surrounding tissue from being harmed through the cutting section 1. Therefore, the percentage of a circumferential movement could be determined accordingly during the optical check before the removal starts. Therefore, the rotational movement in the clockwise and the anticlockwise direction may be only a part of a full turn of the surgical reamer, preferably 80% or less of a full turn. By doing so, the tissue on the opposite side of the cutting section is protected.

[0089] According to another step of an exemplary embodiment of the method for removing bone by a surgical reamer, replacing the currently used surgical reamer by another reamer having a larger diameter may be possible. Therefore the first surgical reamer is pulled out of the patient's body and the second surgical reamer having a larger diameter is guided to the current position by the guide wire passing through the guide channel 5. Thereby, the forces for rotating the reamer having a larger diameter are also transmitted by the standardized connector 3 and the corresponding control and drive mechanism. Therefore, the width of the hole, in which the bone material should be removed, is widened.

[0090] Guiding the surgical reamer without a guide wire or the like may be also be practicable.

[0091] In fact, the 25% circumferential cutting section allows a particularly appropriate cutting of bone material while the surrounding area is protected. In case of having sensitive tissue arranged at the opposite side of the cutting section, it is attainable to move the reamer around a sizable oscillating rotation around another 25% of the circumference without ever contacting the sensitive area with the cutting section.

[0092] All of the above aspects are fully within the scope of the present invention, and are considered to form the basis for alternative embodiments in which one or more combinations of the above-described features are applied, without limitation to the specific combinations disclosed above.

[0093] In light of this, there will be many alternatives which implement the teaching of the present invention. It is expected that one skilled in the art will be able to modify and adapt the above disclosure to suite its own circumstances and requirements within the scope of the present invention, while retaining some or all technical effects of the same, either disclosed or derivable from the above, in light of his comment general knowledge in this art. All such equivalents, modifications or adaptations fall within the scope of the invention hereby defined and claimed.