Ossicular prosthesis

Abstract

According to the invention, a partial-ring-shaped coupling element (2), which extends over approximately 270° in a circumferential direction, for an ossicular prosthesis (1) is provided with two supports (7), for example punched-disc type supports, which protrude laterally relative to each other, said supports supporting the ossicular prosthesis (1) on an ossicle so as to prevent tilting, thereby facilitating implantation of the ossicular prosthesis (1).

Description

ossicular prosthesis

[0001] The invention relates to an auditory ossicular prosthesis having the features of the preamble of claim 1.

[0002] Ossicular prostheses serve as replacements for one or more auditory ossicles in the human middle ear. They transmit vibrations of the eardrum, generated by sound waves, to an existing auditory ossicle, usually the stapes, instead of the replaced ossicle(s). It is also possible to transmit vibrations from an artificial vibration generator implanted in a human ear to an auditory ossicle.

[0003] European patent application EP 2 926 771 A1 discloses an ossicular prosthesis with a strip-shaped coupling element which is bent into a partial ring extending over approximately 270° in a circumferential direction such that an opening remains, by which the coupling element can be placed on a rod-shaped part of an auditory ossicle in order to attach the auditory ossicle prosthesis to the auditory ossicle.

[0004] One problem with implanting an ossicular prosthesis is that the ossicular prosthesis can tilt when the coupling element is placed on an ossicle and when the coupling element is aligned with the ossicle. As a result, if, for example, the prosthetic body of the ossicular prosthesis rests against the footplate in a hole that a surgeon has drilled through the footplate of a stapes to implant the ossicular prosthesis, instead of being guided through the footplate into the inner ear with an annular gap between the prosthetic body and the hole in the footplate of the stapes, sound transmission to the inner ear is impaired. The prosthetic body is a type of shaft that protrudes outward from the partially annular coupling element of the ossicular prosthesis.To make matters worse, a surgeon's view of the middle ear is limited when operating, and therefore a poor fit of the coupling element of the ossicular prosthesis on the ossicle is not always apparent.

[0005] The object of the invention is to propose an ossicular prosthesis of the above type, the hold of which is improved against tipping on an ossicle.

[0006] This object is achieved according to the invention by the features of claim 1. The ossicular prosthesis according to the invention has a partially ring-shaped coupling element for attaching the ossicular prosthesis to an ossicle. In a circumferential direction, the coupling element extends over more than 180° and less than 360°, and preferably over approximately 270°, such that the coupling element has an opening through which it can be placed onto an ossicle. For placement on the ossicle, the coupling element is elastically and / or plastically expanded such that the ossicle fits through the opening of the coupling element. After placement on the ossicle, the coupling element springs back together or is plastically bent back together. Because the coupling element extends over more than 180° in the circumferential direction, it holds on to the ossicle by positive locking in the radial direction.The coupling element is placed on a rod-shaped part of the auditory ossicle, for example on a bracket of a. The stapes, the process or limb of an incus, or the hilt of a hammer. "Stespes," "anvil," and "malleus" refer to the auditory ossicles in a human ear. "Process" and "limb" are two terms for the same part of the incus.

[0007] The coupling element of the ossicular prosthesis according to the invention has one or more supports that protrude laterally from the coupling element, where "laterally" means protruding from the end faces of the coupling element or perpendicular to a radial line and perpendicular to a tangent of the coupling element. The support or supports extend a support on the part of the ossicle onto which the coupling element is mounted, in a longitudinal direction of the part of the ossicle, thereby increasing the tilt resistance of the coupling element on the ossicle and thus of the ossicular prosthesis as a whole against tilting of the coupling element and the ossicular prosthesis about a transverse axis of the part of the ossicle onto which the coupling element is mounted.The invention simplifies implantation of the ossicular prosthesis in a middle ear and increases the probability of a good fit of the coupling element on the ossicle in terms of good sound transmission into an inner ear.

[0008] The dependent claims relate to advantageous embodiments and further developments of the invention.

[0009] The coupling element of the auditory ossicle prosthesis according to the invention preferably has a cylindrical inner circumferential surface. With the inner circumferential surface, the coupling element rests against the auditory ossicle when the coupling element is placed on the auditory ossicle as intended such that the coupling element encloses the auditory ossicle. In the axial direction of the imaginary cylinder encloses the coupling element, the coupling element is preferably short, i.e. the coupling element is preferably narrow in the axial direction in relation to its diameter. The inner circumferential surface of the coupling element is in particular circular-cylindrical, but in embodiments of the invention can also have the shape of a cylinder with a cross-sectional area other than a circle, preferably round. An inner surface of the support, with which the support rests against the auditory ossicle when the The coupling element is placed on the auditory ossicle and is located laterally next to the coupling element on the inner peripheral surface of the coupling element, i.e., on a peripheral surface of the imaginary cylinder enclosed by the coupling element. The inner surface of the support is the surface of the support facing an axis of the imaginary cylinder.

[0010] A conical inner peripheral surface of the coupling element is also possible to adapt to, for example, the limb of an incus that tapers in one direction. In this case, the inner surface of the support is located on the cone that the coupling element encloses. A disadvantage of a conical inner peripheral surface of the coupling element, however, is that the coupling element must be placed on the auditory ossicle with the correct orientation; this means that the inner peripheral surface of the coupling element must taper in the same direction as the enclosed auditory ossicle. As with a cylindrical inner peripheral surface, a truncated cone-shaped inner peripheral surface can have a circular or a round, but not circular, cross-sectional area.

[0011] The coupling element of the auditory ossicle prosthesis according to the invention preferably has supports on both end faces or on both end edges, which protrude laterally from the coupling element in opposite directions. In particular, two supports are arranged opposite each other on the two end faces of the coupling element and protrude laterally from the coupling element in opposite directions. Supports on both end faces of the coupling element extend the support of the coupling element on the auditory ossicle in the axial direction of the coupling element or in a longitudinal direction of the auditory ossicle onto which the auditory ossicle is or will be placed, and thus improve the support of the coupling element on the auditory ossicle against tipping.

[0012] The coupling element may have one support or several supports on one or both end faces, which are arranged evenly or unevenly distributed over a circumference of the coupling element. For example, the coupling element has two supports on one end face or two supports on each end face, which are arranged opposite each other, i.e. the supports are arranged at 180° in the circumferential direction. offset from one another. The supports thus support the coupling element on the auditory ossicle against tilting in two opposite directions in a tilting plane. This embodiment of the invention is particularly advantageous when there is a main tilting direction, i.e. when it is known in which direction the auditory ossicle prosthesis is subjected to the greatest load. Non-opposite supports are also possible, i.e. an offset of the supports other than 180° in the circumferential direction of the coupling element. Supports can be provided in pairs opposite one another on both end faces of the coupling element and / or supports can be arranged offset from one another on the two end faces in the circumferential direction of the coupling element.

[0013] The coupling element of the auditory ossicular prosthesis according to the invention preferably has one or two supports on one or both end faces. Embodiments of the invention with more than two, for example, up to five supports on one or both end faces are also possible.

[0014] One embodiment of the invention provides a wave-shaped or toothed end edge of the coupling element, wherein the waves or teeth on the end edge of the coupling element form the supports. This embodiment of the invention preferably has more than five supports spaced closely apart in the circumferential direction of the coupling element. "Toothed" means an end edge similar to a sawblade or a rack, wherein the teeth, i.e., the supports, viewed radially to the coupling element, can have essentially any desired shape. For example, the teeth or supports are triangular, sawtooth-shaped, rectangular, or trapezoidal.

[0015] In the circumferential direction, the support is preferably short relative to the coupling element, i.e., the support extends, for example, only over approximately half the diameter of the coupling element or less in the circumferential direction of the coupling element. As a result, the support increases the flexural rigidity of the coupling element in the radial direction, i.e., in terms of a change in the diameter of the coupling element, only slightly, and does not impede the placement of the coupling element on the auditory ossicle and the pressing of the coupling element firmly onto the auditory ossicle.

[0016] Preferably, the coupling element has a partially annular strip that is bent perpendicular to its thickness relative to the partial ring, i.e., the thickness of the coupling element is radial to the partially annular coupling element. In the circumferential direction outside the support(s) or between the supports, the coupling element has a constant width in embodiments of the invention, wherein the width is a dimension of the coupling element in the axially parallel direction of the partially annular coupling element. For example, the coupling element has a rectangular, trapezoidal, or possibly an oval ring cross-section, the larger dimension of which extends axially parallel and the smaller dimension of which extends radially to the partially annular coupling element. The support(s) protrude axially parallel or at a conical angle from one end edge or from both end edges of the partially annular strip.In particular, a cross-section of the strip outside or in the circumferential direction of the coupling element between the supports is constant over a circumference of the coupling element.

[0017] The coupling element can be located in a radial plane relative to an axis of the partially annular coupling element. One embodiment of the invention provides for a helical coupling element. This means that the coupling element does not extend in a radial plane relative to its axis, but rather has a—particularly small—pitch, which need not be constant.

[0018] The support(s) of embodiments of the invention have a radially continuous hole. For example, the support(s) have the shape of a circular or non-circular or polygonal, e.g., triangular perforated disc. The hole in the support(s) extends their edge lengths and thus improves the adhesion of the coupling element or its support(s) to the auditory ossicle.

[0019] One embodiment of the invention provides a prosthetic body projecting outward from the coupling element for sound transmission, for example, into the inner ear. The prosthetic body is, for example, a shaft projecting radially outward from the coupling element. In embodiments of the invention, the support of the coupling element is arranged on the coupling element as an extension of the prosthetic body, i.e., in the same plane as the prosthetic body. Viewed in a longitudinal direction of the prosthetic body The support is thus located next to the prosthesis body and supports the auditory ossicle prosthesis according to the invention laterally next to the coupling element against tilting about a radial axis of the coupling element or about a transverse axis of the prosthesis body on the auditory ossicle.

[0020] In one embodiment of the invention, the coupling element has elongated holes or slots arranged obliquely to the circumferential direction. The elongated holes facilitate bending of the coupling element for a given width. The coupling element can thus be more easily molded to the auditory ossicle and is less resilient.

[0021] All features mentioned in the description and / or illustrated in the drawings can be implemented individually or in any combination in embodiments of the invention. Embodiments of the invention that include only a portion of the features of a claim, including the independent claim, are possible.

[0022] The invention is explained in more detail below with reference to exemplary embodiments illustrated in the drawings. They show:

[0023] Figure 1 shows an ossicular prosthesis according to the invention in perspective view;

[0024] Figure 2 is a view of the ossicular prosthesis of Figure 1;

[0025] Figure 3 is a side view of the auditory ossicular prosthesis from Figure 1, rotated by 90° compared to Figure 2;

[0026] Figure 4 is a front view of the auditory ossicular prosthesis of Figures 1 to 3; and

[0027] Figures 5 to 10 show modified versions of the auditory ossicle prosthesis from Figures 1 to 4 according to the invention in a perspective view corresponding to Figure 1.

[0028] In principle, identical parts in the figures are provided with identical reference numbers.

[0029] The auditory ossicle prosthesis 1 according to the invention shown in Figures 1 to 4 is The device is intended for replacing one or more auditory ossicles in a human ear. It comprises a coupling element 2, which is designed to be placed on an auditory ossicle, and a prosthetic body 3, which serves to transmit sound from the auditory ossicle to an oval window or into an inner ear in the human ear.

[0030] The coupling element 2 is partially annular, comprising a strip 4 bent into a partial ring, which—in the exemplary embodiment—extends approximately 270° in a circumferential direction, forming an opening 5 through which the coupling element 2 can be snapped or placed onto the auditory ossicle. Ends 12 of the strip 4 are bent obliquely or radially outward, causing the opening 5 of the coupling element 2 to widen radially toward the coupling element 2, i.e., in the axial direction of the coupling element 2, to widen outward in a funnel shape (Figure 3).

[0031] In the exemplary embodiment, the strip 4 has a flat, rectangular cross-section that is wider than it is thick, with its width B extending in an axial direction of the partial ring formed by the coupling element 2, and its thickness D extending in a radial direction of the partial ring. In the exemplary embodiment, the cross-section of the strip 4 forming the coupling element 2 is constant over its entire circumference.

[0032] The coupling element 2 is partially cylindrical, having the shape of a hollow cylinder that extends—in the exemplary embodiment—over approximately 270° in the circumferential direction and has—in the exemplary embodiment—a circular or partially circular cross-section. An inner circumferential surface 6 of the coupling element 2, with which the coupling element 2 rests against the auditory ossicle when the coupling element 2 is placed on the auditory ossicle, is partially cylindrical.

[0033] The coupling element 2 has supports 7 projecting laterally, i.e. axially parallel, on both of its end faces 13. In the first embodiment of the invention shown in Figures 1 to 4, the supports 7 have the form of circular perforated discs, which are short webs 8 are connected to the coupling element 2. In the exemplary embodiment, the coupling element 2, the webs 8 and the supports 7 are integral with one another.

[0034] In the exemplary embodiment, the supports 7 and the webs 8 are the same thickness as the strip 4 of the coupling element 2 and, as can be seen in Figure 3, they are arranged in alignment with the coupling element 2. The supports 7 are located in the same imaginary hollow cylinder as the coupling element 2 or as the strip 4 of the coupling element 2. In particular, inner surfaces 9 of the supports 7 are located on the same imaginary partial cylinder as the inner circumferential surface 6 of the coupling element 2 or as the inner circumferential surface 7 of the strip 4 of the coupling element 2. With the inner surfaces 9, the supports 7 rest against the auditory ossicle when the coupling element 2 is placed on the auditory ossicle.

[0035] The supports 7 can be considered components of the coupling element 2 or as elements of the auditory ossicular prosthesis 1 according to the invention that protrude from the end faces 13 of the coupling element 2. In the circumferential direction, the supports 7 are short compared to the coupling element 2. As can be seen in Figure 4, the supports 7 extend radially toward the coupling element 2 over approximately half a diameter of the coupling element 2 in the circumferential direction. Because the supports 7 are connected to the coupling element 2 or the strip 4 of the coupling element 2 via the narrow webs 8, the supports 7 hardly increase the flexural rigidity of the coupling element 2 in the radial direction of the coupling element 2.

[0036] The coupling element 2 can be located in a radial plane relative to its axis, meaning its two end edges are located in two parallel planes. In the exemplary embodiment, the coupling element 2, as shown in Figures 2 and 4, is not arranged in a single plane but is somewhat helical.

[0037] In the illustrated embodiment of the invention, the strip 4 of the coupling element 2 has slots 10 arranged obliquely to the circumferential direction and parallel to each other, which pass radially through the strip 4 and which are also regarded as elongated holes The slots 10 facilitate bending of the coupling element 2 to conform to the auditory ossicle.

[0038] In the illustrated and described embodiment of the invention, the prosthesis body 3 is straight and rod-shaped and can also be considered the shaft of the auditory ossicular prosthesis 1 according to the invention. The prosthesis body 3 is arranged at one end of the coupling element 2 in the illustrated embodiment and protrudes radially outward from the coupling element 2 in the illustrated embodiment.

[0039] In the exemplary embodiment of the invention shown in Figures 1 to 4, the supports 7 are arranged opposite the prosthesis body 3 on the coupling element 2, i.e. the two supports 7 are located in a plane with the prosthesis body 3, this common plane being an axial plane of the coupling element 2. The supports 7 support the coupling element 2 and thus also the ossicular prosthesis 1 according to the invention against tilting about a radial axis of the coupling element 2, which lies in a common plane of the coupling element 2 and the prosthesis body 3, on the ossicle when the coupling element 2 is placed on the ossicle in such a way that the coupling element 2 encloses the ossicle and rests against the ossicle with its inner circumferential surface 6 and the supports 7 rest against the ossicle on both sides of the coupling element 2.

[0040] For mechanically fastening the auditory ossicular prosthesis 1 according to the invention in the human ear, the prosthesis body 3 is inserted into or through a hole in a footplate of a stapes (not shown), which has previously been drilled through the footplate, such that an end of the prosthesis body 3 remote from the coupling element 2 protrudes into the inner ear. Alternatively, fastening to an oval window or, for example, to the stapes is also possible, using a second coupling element (not shown), which is or will be arranged on the prosthesis body 3 at a distance from the coupling element 2.

[0041] The coupling element 2 is snapped onto another auditory ossicle (not shown) in such a way that the coupling element 2 encloses the auditory ossicle. In particular, the coupling element 2 is snapped onto a rod-shaped section of the auditory ossicle, for example onto a short or a long leg of an anvil.

[0042] Holes 11 in the supports 7 allow a drop of water to be introduced between the supports 7 and the auditory ossicle. The water is distributed between the inner surfaces 9 of the supports 7 and the auditory ossicle, improving the adhesion of the supports 7 to the auditory ossicle. Furthermore, the holes 11 in the supports 7 extend the edges of the supports 7, which increases adhesion.

[0043] The two supports 7, which brace the auditory ossicles 1 against tipping, facilitate the alignment of the auditory ossicle prosthesis 1 in the human ear and assist a surgeon in implanting the auditory ossicle prosthesis 1 according to the invention into the human ear. The alignment of the auditory ossicle prosthesis 1 in the human ear is essential for good sound transmission from the eardrum to the oval window or into the inner ear.

[0044] A drop of water or other liquid introduced between the coupling element 2 and the supports 7 on the one hand and the auditory ossicle on the other hand increases the hold of the coupling element 2 on the auditory ossicle against tipping during implantation by adhesion and facilitates the surgeon's work.

[0045] In the auditory ossicular prostheses 1 according to the invention shown in Figures 5 to 10, the coupling element 2 or at least the strip 4 of the coupling element 2 and the prosthesis body 3 correspond to Figures 1 to 4, so that in this respect, for the explanation of Figures 5 to 10, reference can be made to the above explanations of Figures 1 to 4. Only a shape and / or arrangement of the supports 7 have been changed. All auditory ossicular prostheses 1 have in common that they have supports 7 projecting laterally from their coupling elements 2, and that the inner surfaces 9 of the supports 7, i.e. the inner sides of the supports 7, are located on the same partial cylindrical surface as the inner circumferential surface 6 of the coupling element 2 or of the strip 4 of the coupling element 2. This means that the inner surfaces 9 of the supports 7 are aligned or are flush with the inner peripheral surface 6 of the coupling element 2 or the strip 4 of the coupling element 2.

[0046] In the embodiment of the invention shown in Figure 5, the supports 7 are triangular when viewed radially onto the coupling element 2, have a hole 11 and are connected in one piece to the coupling element 2 or to the strip 4 of the coupling element 2 via a short web 8.

[0047] Figure 6 shows a variant of an ossicular prosthesis 1 according to the invention, whose supports 7 do not have holes 11. Otherwise, the ossicular prostheses 1 from Figures 5 and 6 are identical.

[0048] The auditory ossicular prosthesis 1 according to the invention shown in Figure 7 has two pairs of supports 7, two supports 7 of a pair being arranged opposite one another on the coupling element 2 and projecting laterally in opposite directions from the coupling element 2 or from the strip 4 of the coupling element 2. The two pairs of supports 7 are arranged offset on the coupling element 2 in the circumferential direction of the coupling element 2. Unlike the auditory ossicular prostheses 1 of Figures 1 to 6, the supports 7 of the auditory ossicular prosthesis 1 from Figure 7 are located outside the axial plane of the coupling element 2, in which the prosthesis body 3 is located. This means that in Figure 7, the supports 7 are not arranged opposite the prosthesis body 3 on the coupling element 2, nor are they arranged at the end 12 of the coupling element 2, from which the prosthesis body 3 projects.The supports 7 can, for example, be offset from one another by 180° in the circumferential direction of the coupling element 2; in Figure 7, the supports 7 have a smaller offset from one another than 180° in the circumferential direction of the coupling element 2.

[0049] In the auditory ossicular prosthesis 1 according to the invention shown in Figure 8, the supports 7 are almost oval and are arranged parallel to the circumferential direction of the coupling element 2 next to the strip 4 of the coupling element 2. In the exemplary embodiment, the supports 7 are almost oval rings, i.e., they have holes 11, and the supports 7 are integrally connected to the coupling element 2 by short webs 8. or connected to the strip 4 of the coupling element 2. Supports 7 without the holes 11 (not shown) are also possible.

[0050] In the embodiment of the invention shown in Figure 9, the supports 7 protrude laterally from the coupling element 2 or from the strip 4 of the coupling element 2 as triangular projections without webs. Furthermore, the coupling element 2 in Figure 9 does not have any slots 10, which is also possible with the other embodiments of the auditory ossicular prostheses 1 according to the invention.

[0051] In the auditory ossicular prosthesis 2 according to the invention shown in Figure 10, the end edges of the coupling element 2 are wave-shaped, i.e., the strip 4 of the coupling element 2 alternately widens and narrows. The laterally outward-facing waves of the end edges of the coupling element 2 form a plurality of supports 7 projecting laterally from the coupling element 2 on both sides. Instead of wave-shaped, the supports 7 or the end edges of the coupling element 2 can also be, for example, triangular, sawtooth-shaped, rectangular, trapezoidal, and so on (not shown).

Claims

Patent claims 1. An auditory ossicle prosthesis, comprising a partially ring-shaped coupling element (2) with two lateral end faces (13) for attachment to an auditory ossicle, wherein the coupling element (2) and the end faces (13) extend over more than 180° and less than 360° in a circumferential direction and have an opening (5) for placing the coupling element (2) on the auditory ossicle, characterized in that the coupling element (2) has at least one support (7) projecting laterally from one of the two end faces (13) in the circumferential direction, which support supports the coupling element (2) on the auditory ossicle against tipping when the coupling element (2) is placed on the auditory ossicle so as to enclose the auditory ossicle.

2. Auditory ossicle prosthesis according to claim 1, characterized in that the coupling element (2) has a cylinder jacket-shaped or cone-shaped inner circumferential surface (6) of an imaginary cylinder or cone, which the coupling element (2) encloses, and an inner surface (9) of the support (7) projects on a circumferential surface laterally to the circumferential direction in extension of the imaginary cylinder or cone.

3. Auditory ossicle prosthesis according to claim 1 or 2, characterized in that the coupling element (2) has supports (7) on both end faces (13).

4. Auditory ossicle prosthesis according to one or more of claims 1 to 3, characterized in that the coupling element (2) has a plurality of supports (7) which are offset from one another in the circumferential direction of the coupling element (2).

5. Auditory ossicle prosthesis according to claim 4, characterized in that the coupling element (2) has no more than five, four, three or two supports (7) on one end face.

6. An auditory ossicular prosthesis according to one or more of claims 1 to 4, characterized in that the coupling element (2) has a wave-shaped or toothed front edge, wherein waves or teeth of the front edge form the supports (7).

7. Auditory ossicle prosthesis according to one or more of the preceding claims, characterized in that the support (7) is shorter in the circumferential direction than 10 percent of a length of the end face (13).

8. Auditory ossicle prosthesis according to one or more of the preceding claims, characterized in that the coupling element (2) has a partially annular strip (4) which has a constant width (B) in the circumferential direction outside the support(s) (7).

9. Auditory ossicle prosthesis according to one or more of the preceding claims, characterized in that the coupling element (2) is helical.

10. Auditory ossicle prosthesis according to one or more of the preceding claims, characterized in that the support (7) has a hole (11) in the radial direction or a perforated disc or is polygonal, in particular triangular.

11. An auditory ossicular prosthesis according to one or more of the preceding claims, characterized in that the auditory ossicular prosthesis (1) has a prosthesis body (3) projecting outwards from the coupling element (2), and in that the support (7) is arranged laterally on the coupling element (2) in extension of the prosthesis body (3).

12. An auditory ossicle prosthesis according to one or more of the preceding claims, characterized in that the coupling element (2) has elongated holes or slots (10) which are arranged in particular obliquely to the circumferential direction.

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