LENGTH-ADJUSTABLE OSSICLE PROSTHESIS

Abstract

A length-adjustable ossicular prosthesis, includes a cylindrical pin serving as a connecting element, which connects a foot element to a head element. The head element is intended to be disposed on an inside of an eardrum, and the foot element is intended to be attached to an anvil in a human ear. The head element is designed as an elliptical ring having an opening, which can be closed by closing a locking mechanism comprising a hook. Two guiding and clamping elements project inwardly from the ring, between which, in an open position, the connecting element is displaceably guided, and which secure the head element non-displaceably and non-rotatably on the connecting element when the ring is closed, and as a result the guiding and clamping elements are tensioned against the connecting element.

Claims

1. A length-adjustable ossicular prosthesis, comprising a head element, which is intended to be disposed at an eardrum, a foot element, which is intended to be disposed at an ossicle or oval window of the human middle ear, and a connecting element, which connects the head element and the foot element, characterized: in that the head element comprises a clip including guiding and clamping elements, which, when the clip is open, displaceably guide the head element at the connecting element and, when the clip is tensioned, securely clamp the head element to the connecting element; in that the clip comprises tensioning elements, by way of which the guiding and clamping elements can be tensioned against the connecting element so as to be securely clamped to the connecting element; and in that the clip comprises a locking mechanism that, when closed, holds the tensioning elements in the tensioned position in which the tensioning elements tension the guiding and clamping elements against the connecting element.

2. The length-adjustable ossicular prosthesis according to claim 1, wherein the guiding and clamping elements comprise mutually facing depressions serving as guides and clamping sections in which the connecting element is accommodated.

3. The length-adjustable ossicular prosthesis according to claim 1, wherein the head element comprises a ring that is open at a point of the circumference, from which the guiding and clamping elements project inwardly so that these are tensioned against the connecting element when the ring is pressed together, and that the ring can be closed by way of the locking mechanism in the tensioned position in which the ring tensions the guiding and clamping elements against the connecting element.

4. The length-adjustable ossicular prosthesis according to claim 3, wherein the locking mechanism comprises a hook on one side of an opening of the ring, which can engage with a mating piece on another side of the opening of the ring.

5. The length-adjustable ossicular prosthesis according to claim 4, wherein the locking mechanism comprises two or more hooks behind one another along the ring on one side of an opening, each of the individual hooks being engageable with the mating piece on the other side of the opening of the ring so that a circumference of the ring and/or a distance of the guiding and clamping elements with respect to one another can be adjusted for adaptation to connecting elements having differing diameters.

6. The length-adjustable ossicular prosthesis according to claim 3, wherein the ring has a reduced cross-sectional area at a point of the circumference allowing for more easy pressing together for tensioning the guiding and the clamping elements against the connecting element.

7. The length-adjustable ossicular prosthesis according to claim 3, wherein the ring, on both sides of the opening, comprises application surfaces on the outer side thereof for applying a closing tool for closing the ring, which are shaped so that the applied closing tool does not slip in the circumferential direction of the ring when exerting a closing force on the ring.

8. The length-adjustable ossicular prosthesis according to claim 3, wherein the guiding and clamping elements are disposed at a greater distance with respect to the opening of the ring than with respect to a point of the circumference which is located opposite the opening.

9. The length-adjustable ossicular prosthesis according to claim 1, wherein the foot element is designed to be provided at the stirrup or the oval window of the middle ear of a person.

Description

[0020] The invention will be described hereafter in greater detail based on one exemplary embodiment shown in the drawings. In the drawings:

[0021] FIG. 1 shows an ossicular prosthesis according to the invention in a perspective illustration; and

[0022] FIG. 2 shows a head element of the ossicular prosthesis in a plan view.

[0023] The ossicular prosthesis 1 according to the invention shown in the drawings comprises a head element 2, a foot element 3, and a connecting element 4 connecting the head element 2 and the foot element 4. The ossicular prosthesis 1 is intended to replace one or more ossicles in a human ear. The head element 2 is intended to be disposed on an inside of an eardrum of the ear, and the foot element 3 is intended to be provided at an ossicle, and in particular at a stirrup or an oval window in the middle ear of a person. The ossicular prosthesis 1 transmits vibrations of the eardrum, generated by sound waves, to the stirrup or the element of the ear to which the foot element 3 is attached. Eardrum in the present context shall be understood to mean a present, partially present and artificial complete or partially reconstructed eardrum, as well as a partially present eardrum, the remaining part being reconstructed. The reconstruction encompasses any form of producing a vibratable membrane, for example using body tissue or a synthetic vibrating membrane for mechanical sound transmission.

[0024] According to the invention, the head element 2 of the ossicular prosthesis 1 is designed as a clip 15. In the exemplary embodiment, this comprises an approximately elliptic ring 5, which is open at a point of the circumference and, at an opposing point of the circumference or an opposing section of the circumference, is thinner than elsewhere, which is to say has a reduced cross-sectional area 6. In the exemplary embodiment, the open point of the circumference, which is referred to as opening 7 of the ring 5 here, and the reduced cross-sectional area 6 are located opposite one another at the vertices of the ellipse.

[0025] Two guiding and clamping elements 8 project inwardly from the ring 5 at points of the circumference that are located opposite one another with respect to a main axis of the ellipsis, which at the mutually facing edges include circular arc-shaped depressions, which are situated on an imaginary circle. The depressions form guides and clamping sections 9 for the connecting element 4. The depressions can also have a different shape, for example a V shape. It is essential that the guides and clamping sections 9 displaceably guide the head element 2, when open, at the connecting element 4 in a longitudinal direction of the connecting element 4, and, when closed or tensioned, secure the head element 2 at the connecting element 4 by clamping to prevent displacement and rotation. Securing to prevent rotation is also conceivable by way of form fit with a connecting element 4 having a non-circular cross-section, on which the head element cannot be rotated (not shown). A clamping force of the closed or tensioned head element 2 is so great that the head element 2 does not move with respect to the connecting element 4 when stresses occur in the human ear. However, the clamping force is not so great that the head element 2 deforms transversely to the axial plane of the ring 5 of the head element 2 over the long implanted time period. A displacement or rotation of the head element 2 by way of a greater force is not precluded.

[0026] On one side of the opening 7, the ring 5 comprises a hook 10 on the outer side thereof, and on another side of the opening 7, this comprises a hook on the inner side thereof. The hook on the inner side of the ring 5 forms a mating piece 11 for the hook 10. The hook 10 and the mating piece 11 thereof form a locking mechanism 12 and can engage with one another for closing the ring 5 or the head element 2, designed as a clip 15, of the ossicular prosthesis 1 according to the invention, as is shown in FIG. 1. FIG. 2 shows the head element 2 with an open locking mechanism 12, and an open ring 2 or an open clip 15, the hook 10 not engaging with the mating piece 11.

[0027] At a slight distance in the circumferential direction with respect to the hook 10 and the mating piece 11, the ring 10 of the head element 2 has recesses on the outer side thereof, whereby application surfaces 13 for applying a closing tool, which is not shown, are formed. The application surfaces 13 extend parallel to one another and parallel to the main axis of the elliptical ring 5, or the application surfaces 13 extend in a slightly diverging manner in the direction of the opening 7 so that a closing tool applied to the application surfaces 13 does not slip in the circumferential direction of the ring 5.

[0028] For closing the ring 5, and thus the clip 15 of the head element 2, the application surfaces 13 are made to approach one another using, for example, pliers (not shown) as a closing tool, which are applied to the application surfaces 13, and as a result, the hook 10 is made to approach the mating piece 11 of the locking mechanism 12 until the hook 10 engages with the mating piece 11, whereby the ring 5 is closed. Closing of the ring 5 in another manner is not precluded.

[0029] When the ring 5 is being closed, the reduced cross-sectional area 6 forms a kind of hinge by way of which the arc-shaped sections of the ring 5 between the reduced cross-sectional area 6 and the opening 7 are pivotably connected to one another. The arc-shaped sections of the ring 5 between the reduced cross-sectional area 6 and the opening 7 can also be interpreted as arms, tensioning arms or, generally speaking, as tensioning elements 14 of the clip 15. These are elastic in the exemplary embodiment.

[0030] When the ring 5 is being closed, the two guiding and clamping elements 8 and the guides and clamping sections 9 move toward one another and/or are pressed against the connecting element 4, which can also be interpreted as tensioning of the ring 5, of the head element 2 or of the clip 15. The guiding and clamping elements 8 and the guides and clamping sections 9 are located between the reduced cross-sectional area 6, which forms the hinge, and the application surfaces 13 for the closing tool and, as is the case in the exemplary embodiment, are preferably located closer to the reduced cross-sectional surface 6, resulting in a force multiplication: the closing force for pressing the application surfaces 13 together is smaller than a clamping force with which the guides and clamping sections 9 are pressed, which is to say tensioned, against the connecting element 4.

[0031] In the exemplary embodiment, the head element 2 is produced in one piece from sheet metal by way of laser cutting. Other production options are not precluded, for example a production from multiple, for example welded pieces and/or a production from wire.

[0032] In the shown and described exemplary embodiment of the invention, the connecting element 4 is a cylindrical pin, which passes between the guides and clamping sections 9 of the guiding and clamping elements 8 of the head element 2 and to the one end of which the foot element 3 is fastened, which in the exemplary embodiment has a bell shape, other shapes being possible. The connecting element 4 does not necessarily have to be a cylindrical pin.

[0033] When the ring 5 or the head element 2 designed as a clip 15 is open, which is to say the hook 10 is not engaged with the mating piece 11, the head element 2 can be displaced on the connecting element 4 in the longitudinal direction thereof without friction or with friction, and as a result, a distance between the head element 2 and the foot element 3 can be adjusted. Adjusting the distance between the head element 2 and the foot element 3 can also be interpreted as a length adjustment of the ossicular prosthesis 1. By closing the locking mechanism 12, the ring 5, or the head element 2 designed as a clip 15, the guides and clamping sections 9 of the guiding and clamping elements 8 are pressed or tensioned against the connecting element 4 and hold the head element 2 non-displaceably and non-rotatably on the connecting element 4. The closing can also be interpreted as tensioning, and the closed position of the ring 5 or of the clip 15 can be interpreted as a tensioned position.

[0034] Finally, the connecting element 4 is cut off on a side of the head element 2 which faces away from the foot element 3 so that the connecting element 4 does not protrude beyond the head element 2 on the side facing away from the foot element 3. Cutting off the connecting element 4 can also be interpreted as cutting the connecting element 4 and the ossicular prosthesis 1 to length.

[0035] The elliptical shape of the ring 5 is not mandatory for the invention, and the ring 5 can also have another, preferably rounded, but potentially angular, shape. The ring 5 is also not mandatory for the invention in every case; what is necessary is that the head element 2 is designed as a clip 15, comprising tensioning arms or similar tensioning elements 14, from which the guiding and clamping elements 8 project in the direction of the connecting element 4 so that the guides and clamping sections 9 thereof can be tensioned against the connecting element 4 so as to securely clamp the head element 2 to the connecting element 4, and the tensioning arms, or generally speaking the tensioning elements 14, can secure the head element 2 in this tensioned position, for example by way of a locking mechanism 12.