Device for holding a transmitter arrangement interacting with an image or signal acquisition device of a surgical navigation system

Abstract

To provide a device capable of holding a transmitter mechanism with a large degree of freedom.SOLUTION: The invention relates to a device (2) for holding a transmitter arrangement (6) interacting with an image or signal acquisition device (4) of a surgical navigation system during an operation on a patient, comprising a base part (16), at least one fixing means (18) to be introduced into a bone (8), and a joint arrangement (21). The joint mechanism (21) comprises a head (30), a shaft (32) supporting the transmitter mechanism (6), and a two part receiver (24), wherein the head (30) and the transmitter mechanism (6) are fixable in a desired orientation. The head (30) has a convex or concave portion (48) or a flat facet section (42) on its surface (39). The head (30) is fixable in one of a plurality of discrete and selectable orientations relative to the receiving part (24). Adjacent discrete, selectable orientations are at an angle of at most 15 ° to each other, measured from the center of the sphere.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a device for holding an active or passive transmitter mechanism that interacts with an image or signal acquisition device of a surgical navigation system during surgery on a patient, comprising a base portion, at least one fixation means that is inserted into the patient's bone, in particular the femur or tibia in the case of a total hip or knee replacement, to position the base portion in a fixed orientation relative to the bone during surgery, and a joint mechanism that is held by the base portion. [Background technology]

[0002] Such a device has been disclosed by the applicant, in which the joint mechanism can be fixed and pivoted about two axes. However, only four rotational positions are possible around the upward axis. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention is based on the problem of further improving a device of the type described above, which can be manufactured in a cost-effective manner, which gives the surgeon greater freedom in positioning the base of the device on the patient's bone in a surgical situation, and which is also easy and safe to operate. [Means for solving the problem]

[0004] This problem is solved in accordance with the present disclosure for a device of the type described above. The joint mechanism is designed to include a head whose basic geometry is spherical, a shaft extending therefrom and supporting a transmitter mechanism, and a two-part receiver for the head. The receiver allows the head and transmitter mechanism to be fixed in a desired orientation relative to the bone. The head also has a surface with a radially outwardly protruding convex portion, particularly a rounded convex portion, or a radially inwardly sunken concave portion, particularly a dome-shaped concave portion, or a flat faceted section. The receiver for the head further has an inner section with an at least partially complementary shape, so that the head can be fixed in one of a plurality of discrete, selectable orientations relative to the receiver. The convex portions, concave portions, or faceted sections are distributed across the surface of the head, and the discrete, selectable orientations located adjacent to each other form an angle of at most 15° relative to one another, measured from the center of the sphere.

[0005] Therefore, the joint mechanism should not aim for a precise spherical shape with a concentric clamp, as the applicant believes this provides insufficient security against undesired, unintended adjustment after a single fixation. This is because it is not possible to guarantee that the desired orientation will not shift again, especially with a relatively low clamping force. Instead, a form-fit fixation between the head of the joint mechanism and the receiving part of the two parts should be used to achieve play-free orientation and fixation of the device. The fact that the discrete, selectable orientations have angles of up to 15°, particularly up to 12°, and preferably up to 10°, means that a high degree of freedom can be achieved when positioning the base part on the bone to align the head with the transmitter mechanism so that the plane on which the multiple transmitters are installed is approximately perpendicular to the main axis of the image acquisition device.

[0006] At least one fixation means is an anchor, screw, or threaded pin that can be secured to a clamp receptacle on the base portion so that the base portion can be locked in place after the fixation means is inserted into the patient's bone.

[0007] More advantageously, the at least one fixation means is sufficiently long so that the base can be positioned 5.0 to 50 mm from the bone surface.

[0008] As already indicated, it will prove convenient for the transmitter mechanism to support at least three, and in particular four, transmitters arranged on intersecting legs in a plane, one leg being formed by a shaft extending away from the head or being attachable directly or indirectly to the head.

[0009] The form-fitting fixing of the head to the receiving part does not require the multi-part receiving part to completely surround the head, which could also limit the pivotal movement of a shaft arranged therein. Rather, it proves advantageous and sufficient for the receiving part to surround the head by an angle of at least 120°, in particular at least 130°, in particular at least 140°, in particular at most 170°, in particular at most 160°, in particular at most 150°, when viewed in a cross section surrounding the shaft, and by an angle of at least 30°, in particular at least 40°, in particular at most 90°, in particular at most 80°, in particular at most 70°, in particular at most 60°, when viewed in a cross section perpendicular to the shank.

[0010] In principle, it is conceivable and sufficient for the receiving part or each part of the receiving part to have only complementary inner compartment areas, which to some extent can engage with the convex, concave or facet compartments of the head in a form-fitting and force-fitting clamping or fixed connection. However, it is also conceivable that the entire inside of the individual parts of the receiving part is designed to complement the surface of the head.

[0011] It is further advantageous if the parts of the receiving part can be fastened to one another, in particular by means of a screw connection, a toggle or a knee-lever mechanism, and the parts can be fastened to one another and released from one another without tools, i.e. by purely manual operation.

[0012] According to one embodiment of the present invention, the head has a recess on its surface, which may in particular be cylindrical, conical or dome-shaped. At least one projection is therefore provided on the inner compartment of the receiving part, which can fully or partially engage in the recess of the head positioned opposite it when the parts of the receiving part are urged or clamped together with the enclosed head.

[0013] A screw connection, a toggle mechanism or a knee-lever mechanism can conveniently be used for this purpose.

[0014] According to a further embodiment of the invention, the head has a recess on its surface, which recess can be cylindrical, conical or spherical, and the inner section of the receiving part is advantageously formed with at least one protrusion with a curved, in particular spherically curved, free end, the radius of curvature of which is greater than the radius of curvature of the recess in the area of ​​the surface of the head. The fact that the nominal dimensions of the free end of the protrusion of the receiving part are greater than the nominal dimensions of the recess in the surface of the head allows for self-centering between the head and the receiving part, which is practically convenient and therefore advantageous.

[0015] According to a further embodiment, biasable locating pins are provided protruding radially inward from an inner compartment of the receiving part, which pins are displaceable within the receiving part and can respectively at least partially engage with radially inwardly concave, in particular dome-shaped, recesses in the head to fix the head in one of a plurality of discrete, selectable orientations relative to the receiving part. The use of biasable locating pins, in particular spring-loaded locating pins of rounded design, allows for easy manipulation when adjusting or setting the head within the receiving part.

[0016] Here too, it will prove advantageous if the positioning pin has a curved, in particular spherically curved, free end, the radius of curvature of which is greater than the radius of the recess in the area of ​​the surface of the head.

[0017] Following a further development that can be described as particularly advantageous, it is proposed that the two-part receiving part preferably has flushing channels opening inwards in each of the parts, so that the intermediate space between the receiving part and the head can be cleaned by introducing a flushing liquid outside the surgical situation.

[0018] Further features, details and advantages of the invention are apparent from the accompanying claims and drawings, as well as the following description of preferred embodiments of the device according to the invention. [Brief explanation of the drawings]

[0019] The drawings show the following: [Figure 1] 1 is a schematic diagram of an apparatus for holding a transmitter mechanism during surgery on a patient, in accordance with the present invention; [Figure 2] FIG. 2 is a perspective view of a joint mechanism of the device according to FIG. 1; [Figure 3] 3 is a perspective view of the receiving part of the joint mechanism according to FIG. 2; FIG. [Figure 4] FIG. 3 is a perspective view of the head of the joint mechanism according to FIG. 2 with a flat facet section. [Figure 5] FIG. 10 is a perspective view of a further embodiment of the head of a further joint mechanism. [Figure 6] FIG. 1 is a schematic diagram of one embodiment of a joint mechanism. [Figure 7] 10A-10C are schematic diagrams of different nominal dimensions for the receiving part of the joint mechanism and the partially interlocked convex and concave parts on the spherical surface. DETAILED DESCRIPTION OF THE INVENTION

[0020] 1 shows a schematic diagram of an apparatus (generally designated 2) for holding a transmitter mechanism 6, which interacts with an image or signal acquisition device 4, in an operating room situation on a patient, i.e., a bone 8 of the patient to be treated. The transmitter arrangement 6 preferably comprises a plurality of active or passive transmitters 10, which in this case are arranged in an array in a plane formed by two legs 12 of the transmitter arrangement 6, to which the transmitters 10 are fixed. Signals emitted from or reflected by the transmitters 10 are acquired by the image or signal acquisition device 4 and further processed in a computing device of the surgical navigation system, and an evaluation, recommended treatment, and similar information for the surgeon is displayed on a display (schematically designated 14).

[0021] The device 2 comprises a diagrammatically represented base part 16, which can be fixed to the patient's bone 8 at a selectable distance from the bone by means of two fixing means 18, for example in the form of threaded pins 20. This is achieved by means of respective clamping screws 22, which fix the base part 16 to the associated threaded pins 20.

[0022] The device 2 further comprises a joint mechanism 21 with a two-part receiver 24, both parts 26, 28 of which form a kind of clamping jaw for a head 30 whose basic geometry is spherical. A shaft 32 extends from the head 30 and which merges, in the schematic view, into the leg 12 of the transmitter mechanism 6. The two parts 26, 28 of the receiver 24 can be moved towards or away from each other by means of a threaded spindle 34, so that the head 30 can be set in a clamped position in the receiver 24 and released again.

[0023] The head 30 (shown diagrammatically in FIG. 1 ) has a radially outwardly extending, particularly rounded, protrusion, or a radially inwardly extending, particularly dome-shaped, recess, or a flat, faceted section on its surface 36. Depending on the design, one and / or the other parts 26, 28 of the receiver 24 may have an inner section 38 that is at least partially complementary in shape to the head 30, thereby enabling the head 30 to be fixed in a plurality of discrete, selectable orientations relative to the receiver 24. Adjacent, separately selectable orientations form angles of 15° or less with respect to each other, measured from the center of the sphere.

[0024] FIG. 2 shows a first embodiment of the device 2 according to the present disclosure in a schematic view of the joint arrangement 21, which includes a two-part receiving part 24 and a head 30 with a shaft 32 leading to the transmitter arrangement 6. In this embodiment, the head 30 includes a flat facet section 40 on its surface 39. The two parts 26, 28 of the receiving part 24 include respective inner sections 38 of complementary shape, which are shown next to the part 26 in the top view of FIG. 3. It can be seen that the inner sections also include facet sections 40 with a shape and arrangement complementary to the facet section 42. Furthermore, an embodiment is realized and illustrated here, according to which a flushing channel 44 is formed in the receiving part 24, which opens into the inner section 38 of the receiving part 24. This allows for cleaning of the space between the receiving part 24 and the head 30. Furthermore, FIGS. 2 and 3 show an adjustment screw or threaded spindle 34, or a recess 46 for this purpose, in the receiving part 24. FIG. 4 again shows the head 30 with a flat faceted section 40 .

[0025] FIG. 5 illustrates another exemplary embodiment of a device according to the present disclosure, in which the head 30 is formed with a radially inwardly concave, dome-shaped recess 48 reminiscent of the surface structure of a golf ball. In the illustrated example, the recess 48 is spherical, although this is not required. To achieve a form-fit clamping fixation of the head 30 in the receiver 24, as shown diagrammatically in FIG. 6, each inner section 38 of the parts 26, 28 of the receiver 24 is provided with a radially inwardly extending protrusion 50 that can engage with the recess 48 in the surface 39 of the head 30 when the head 30 is properly positioned. In the illustrated example, the protrusion 50 is formed by the free end 52 of a pin 54 to which a force can be applied, as indicated diagrammatically by the depiction of a spring element 56.

[0026] 7 again shows, in a schematic manner, that the nominal dimension or radius of curvature of the inwardly extending protrusion 50 in the receiver 24 may be greater than the nominal dimension of the inwardly recessed recess 48 in the head 30, thereby achieving a self-centering effect.

[0027] It can be seen that the device 2 described herein, in its various embodiments, is user-friendly and can be used in the operating room with minimal risk of failure. Due to the arrangement of the interacting concave, convex or facet sections of the sphere on the one hand, and the complementary shapes of the inner sections of the receiving parts on the other hand, a large number of discrete and selectable orientations of the sphere and thus of the transmitter mechanism can be selected and fixed, so that the available orientations are selectable within a narrow grid, although not without steps.

Claims

1. 1. A device (2) for holding a transmitter mechanism (6) that interacts with an image or signal acquisition device (4) of a surgical navigation system during surgery on a patient, comprising: a base portion (16); at least one fixation means (18) that is inserted into the patient's bone (8), in particular into the femur or tibia in the case of a total hip or knee replacement, to position the base (16) in a fixed orientation relative to the bone (8) during surgery; a joint mechanism (21) held by the base portion; The joint mechanism (21) is designed with a head (30) of generally spherical shape, a shaft (32) extending therefrom and supporting a transmitter mechanism (6), and a two-part receiver (24) for the head (30), with respect to which the head (30) and transmitter mechanism (6) can be fixed in a desired orientation relative to the bone (8); the head (30) has on its surface (39) a radially outwardly extending, in particular rounded, convex portion, or a radially inwardly concave, in particular dome-shaped, concave portion (48), or a flat faceted section (42); 1. A device (2) comprising: a receiving portion (24) for a head (30) having an inner section (38) of a shape complementary thereto, at least in certain regions, so that the head (30) can be fixed in one of a plurality of discrete, selectable orientations relative to the receiving portion (24); protrusions, recesses (48) or facet sections (42) distributed across a surface (39) of the head (30), and adjacent discrete, selectable orientations form an angle of at most 15° with respect to each other, measured from the center of a sphere.

2. 2. The device (2) according to claim 1, characterized in that adjacent discrete selectable orientations form an angle of at most 12°, in particular at most 10°, with respect to one another, measured from the center of the sphere.

3. 3. The device (2) according to claim 1 or 2, characterized in that the at least one fixing means (18) is an anchor, a screw or a threaded pin (20) which can be fixed in a clamping receptacle of the base part (16) so that the base part (16) can be fixed in place after the fixing means (18) has been inserted into the bone (8).

4. 4. The device (2) according to claim 1, 2 or 3, characterized in that the at least one fixing means (18) has a length such that the base part (16) can be positioned at a distance of 5.0 to 50 mm from the bone surface.

5. the transmitter mechanism (6) supports at least three, in particular four, transmitters arranged on intersecting legs (12) in one plane; A device (2) according to any one of claims 1 to 4, characterized in that one leg (12) is formed by a shaft (32) extending away from the head (30) or can be attached directly or indirectly to it.

6. 6. The device (2) according to any one of claims 1 to 5, characterized in that the receiving part (16), when viewed in a cross section surrounding the shaft (32), surrounds the head (30) at an angle of at least 120°, in particular at least 130°, in particular at least 140°, in particular at most 170°, in particular at most 160°, in particular at most 150°, and when viewed in a cross section perpendicular to the shaft (32), surrounds the head (30) at an angle of at least 30°, in particular at least 40°, and at most 90°, in particular at most 80°, in particular at most 70°, in particular at most 60°.

7. 7. Device according to any one of claims 1 to 6, characterized in that the parts (26, 28) of the receiving part (24) are fastenable to one another, in particular by means of a screw connection, a toggle or a knee-lever mechanism.

8. The head (30) has a recess (48) in its surface (39); The recess (48) of the head (30) is in particular cylindrical, conical or dome-shaped; 8. A device according to any one of claims 1 to 7, characterized in that at least one projection (50) is provided on the inner section (38) of the receiving part (24), which can fully or partially engage in a recess (48) of the head (30) positioned opposite it when the parts (26, 28) of the receiving part (24) are urged or clamped together with the enclosed head (30).

9. At least one projection (50) is formed with a curved, in particular spherically curved, free end (52); 9. The device (2) according to claim 8, characterized in that the radius of curvature of the spherically curved free end (52) is greater than the radius of the recess (48) in the area of ​​the surface of the head (30).

10. 10. The device according to claim 1, characterized in that radially inwardly biasable positioning pins (54) protrude from an inner section (38) of the receiving part (24), which pins are displaceable within the receiving part (24) and which each at least partially penetrate into a radially inwardly recessed, in particular cap-shaped, recess (48) in the head (30), thereby fixing the head (30) in one of a plurality of discrete, selectable orientations relative to the receiving part (24).

11. The locating pin (54) has a curved, in particular spherically curved, free end (52), 11. Device (2) according to claim 10, characterized in that the radius of curvature of the curved free end (52) is greater than the radius of the recess (48) in the region of the surface (39) of the head (30).

12. The device (2) according to any one of claims 1 to 11, characterized in that the two-part receiving part (24) preferably has an inwardly opening irrigation channel (44) in each of the parts (26, 28), making it possible to clean the intermediate space between the receiving part (24) and the head (30) by introducing an irrigation liquid outside the surgical situation.

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