DE102022119451B3 - Improved length-adjustable auditory ossicle prosthesis with in-situ elongation from the head plate - Google Patents

Abstract

An auditory ossicle prosthesis (10) with first and second fastening elements (11, 12), a connecting element (13) and web elements (14), is characterized in that the web elements open directly into and with coupling areas (15) of the first fastening element within the head plate plane are movably but non-detachably connected, that all web elements are movably but releasably connected to a shaft-shaped coupling element (16) and are firmly but releasably connected during operation, the coupling element in turn being rigidly connected at the other end to either the first or the second fastening element, that the web elements form the connecting element with the coupling element, that the web elements enclose the coupling element in a clamp-like manner, or the coupling element engages in a force-fitting manner in the web elements, that the web elements are in-situ in the middle ear when a force is introduced parallel to the longitudinal axis (z) in sections radially spread apart from the longitudinal axis and thus shorten the axial functional length of the prosthesis, but increase it when a force is applied antiparallel to it, and that the bar elements maintain their set radial position in situ without the action of a force. This means that length adjustment can be carried out in situ with the prosthesis already placed, even from above, ensuring a uniform and symmetrical elongation of the prosthesis and also making it possible to use it with partial prostheses with a low axial height and/or a short functional length.

Description

The invention relates to an auditory ossicle prosthesis which replaces or bridges at least one link or parts of a link of the auditory ossicle chain, the auditory ossicle prosthesis having a first fastening element designed as a head plate for mechanical contact with the eardrum and/or the hammer handle at one end and a second fastening element at its other end Fastening element for mechanical connection with a link or parts of a link of the auditory ossicle chain or with the inner ear as well as a connecting element which connects the two fastening elements to one another in a sound-conducting manner along a longitudinal axis, and wherein the connecting element has web elements which - at least in sections - radially from the longitudinal axis can be more or less spread outwards and thereby shorten the axial length of the auditory ossicle prosthesis more or less.

Such a device is known from US 10,687,937 B2 (=Reference [1]).

Background of the invention

Ossicle prostheses are used to transmit sound from the eardrum to the inner ear when the ossicles of the human middle ear are completely or partially missing or damaged. The auditory ossicle prosthesis has two ends, whereby, depending on the specific circumstances, one end of the auditory ossicle prosthesis rests on the eardrum or the hammer handle, for example by means of a head plate, and the other end of the auditory ossicle prosthesis is attached, for example, to the stirrup of the human auditory ossicular chain or is dipped directly into the inner ear. In many cases, sound conduction between the eardrum and the inner ear is only possible to a limited extent with the known ossicular prostheses because they can only replace the natural anatomical formations of the ossicular chain to a very limited extent. (See for example DE 42 10 235 C1 ; EP 0 809 982 B1 ; US 6,387,128 B1 (=Reference [2])).

After the prosthesis has been surgically placed in the middle ear and the eardrum is closed again, the so-called healing phase begins. During this time, scars form and these cause unpredictable forces that can cause the prosthesis to move out of its local position. If there is a stiff connection between the headplate and the shaft, increased pressure peaks can occur between the edge of the headplate and the eardrum or the transplant between the eardrum and the headplate. These can be so high that penetration or extrusion through the eardrum would result. For this reason, it is very helpful if the prosthesis has a certain degree of post-operative mobility so that the head plate can automatically adjust to the position of the eardrum post-operatively.

Since the anatomical conditions of the ear, such as the position, shape and size of the stirrup, the anvil, the malleus and the eardrum, vary, it is very advantageous if auditory ossicle prostheses are not rigid, but have a certain flexibility or variability .

In order to achieve such flexibility/variability, various fastening and coupling devices for auditory ossicles, which have elastic parts and/or joints, are known. Such an articulated connection between a fastening element that can be mounted on the stirrup foot plate and the elongated shaft is, for example, in EP 1 181 907 B1 (=Reference [3]) and is offered by the applicant under the brand name “Ball-Joint”.

Another complication that occurs in various ways arises from under-ventilation of the middle ear space and the associated inflammation, tumor formation, adhesions in the eardrum area and stiffening of the eardrum. For example, in the case of a dysfunction of the Eustachian tube, negative pressure can occur in the middle ear, which can cause the eardrum to bulge or protrude (so-called retraction) and, as a result, to grow together with the stapes, for example. In order to counteract this and to be able to follow postoperative movements of the eardrum, the head plates in known auditory ossicle prostheses are designed to be tiltable relative to the connecting element that connects the head plate to the second fastening element and is usually designed as an elongated shaft. Such a head plate, which is rigid in itself but can be tilted relative to the connecting element, is described, among other things, in US 2004 /0 162 614 A1 (=Reference [4]).

While reference [3] discloses an ossicular prosthesis in which the head plate has a built-in ball joint connected to the connecting shaft of the two fastening elements EP 1 833 424 B1 (=Reference [5]) even has a connecting shaft designed as a ball chain. This allows the final axial length of the prosthesis to be determined at least in stages by selecting a certain number of balls in the chain and cutting off the excess balls.

However, the disadvantage of these known ossicle prostheses is that due to the rigid tilting of the head plate during local medial movements of the eardrum, the opposite side of the head plate is simultaneously moved laterally outwards, which creates pressure peaks on the eardrum.

The EP 1 972 307 B1 (=Reference [6]) discloses an auditory ossicle prosthesis with a highly flexible head plate, in which, on the one hand, the advantages of the prosthesis according to the above-mentioned reference [5], but on the other hand also the advantages of the prostheses described in reference [4] are retained, although the common ones Disadvantages of a rigid tilting of the head plate can be avoided. However, the problem with the auditory ossicle prosthesis according to reference [6] is its insertion into the patient's middle ear, because the head plate protrudes considerably to the side, particularly in the radial direction with respect to its longitudinal axis, and can only be surgically inserted through the eardrum area into the middle ear using a large artificial opening. This large opening is of course more difficult to grow back together post-operatively and also leaves correspondingly large scars.

The head plate in reference [6] includes flexible web elements which run within the head plate plane and connect a radially outer ring area of the head plate with a central coupling area arranged radially in the middle of the head plate. These web elements - together with the radially outer ring area and the central coupling area - are an integral part of the head plate disclosed in reference [6]. They are geometrically designed in such a way that when there are local medial movements of the eardrum, they follow such a medial movement - also locally - but do not pass on the movement to distant areas of the head plate.

However, the web elements are not designed for any radial compression of the head plate within the head plate plane and thus a radial reduction in the head plate diameter, possibly for the purpose of making it easier to pass through the eardrum, but would be unsuitable for such an application. This is particularly the case because the radially outer ring region is designed to be rigid and would therefore not follow the attempt at such radial compression or would at most bend uncontrollably.

The ossicle prosthesis described in reference [6] is also absolutely unsuitable for a change in length in the direction of the z-axis, since the connecting element, which runs along the z-axis and rigidly connects the head plate with the second fastening element, is sound-transmitting, but as such is designed to be rigid. Flexibility of the length of the connecting element in the z-direction is excluded and not desired in the auditory ossicle prosthesis according to reference [6].

The EP 3 311 773 B1 (=Reference [7]), in contrast, describes an auditory ossicle prosthesis with a head plate that can be folded like an umbrella, by means of which the prosthesis can be surgically inserted into the middle ear in an almost minimally invasive manner through a small opening in the eardrum.

Another important issue when implanting auditory ossicle prostheses is the setting of the correct axial length of the prosthesis, which is optimally adapted to the individual conditions and geometric conditions in the patient's middle ear.

The reference [5] discussed above already suggests a ball chain with detachable end balls. Unfortunately, this does not allow continuous length adjustment, but only gradual length adjustment.

A variable-length auditory ossicle prosthesis with a displacement mechanism for continuous length adjustment built into the connecting element between the first and second fastening elements is in the DE 10 2007 041 539 B4 (=Reference [8]).

Instead of such a displacement mechanism - which is relatively complex to produce - the EP 2 238 946 B1 (=Reference [9]) presents a length-variable auditory ossicle prosthesis in which an accordion-like structure is built into the connecting element. The axial length of the auditory ossicle prosthesis can then be shortened by axially compressing this structure and increased by pulling it apart.

In the EP 2 601 909 B1 (=Reference [10]) In turn, for the axial length adjustment of the auditory ossicle prosthesis, a displacement mechanism is provided in the connecting element, which comprises a receiving part and an insertion part which encompasses the receiving part with two legs in a clamp-like manner, the receiving part and the insertion part being movable relative to one another in the axial direction of the connecting element .

Finally, a laser-activated, variable-length auditory ossicle prosthesis is available EP 3 130 315 B1 (=Reference [11]). It is proposed that the connecting element with stretchable and/or compressible, loop-like folded partial strands made of a material with a shape to build memory. Activation surfaces are connected to the loops of these partial strands in a heat-conducting manner, which can cause thermal activation and thus deformation of the loops through the action of heat. In this way, the axial length of the ossicle prosthesis can be changed and adjusted as desired.

Finally, the reference [1] cited above discloses a generic auditory ossicle prosthesis with all of the feature complexes defined at the beginning. In particular, it is proposed to provide strip-like web elements in the connecting element, which can be spread radially outwards away from the longitudinal axis and thereby shorten the axial length of the connecting element and thus the axial length of the auditory ossicle prosthesis. The web elements are spread from the side, i.e. in the radial direction with respect to the connecting element. However, an increase in the axial length is not intended for this mechanism of action. Without additional measures, this length adjustment is only possible before the prosthesis is inserted into the patient's middle ear, but not in situ in the implanted state.

Task of the invention

The object of the present invention is, in contrast, to improve a generic length-adjustable auditory ossicle prosthesis of the type defined at the outset using technical means that are as simple as possible in such a way that length adjustment can be carried out in situ in an uncomplicated and cost-effective manner when the prosthesis has already been placed, and the length adjustment of the prosthesis is also possible from above is that a uniform and symmetrical elongation of the prosthesis is ensured, and that an application of the invention is also made possible, for example, in partial prostheses with a low axial height and/or a short functional length.

Brief description of the invention

According to the invention, this object is achieved in a surprisingly simple and effective manner in that the web elements open at one end directly into coupling areas of the first fastening element within the head plate level and are connected to these in a movable but inseparable manner, in that all web elements with a coupling element are also movable and in Operation are firmly but releasably connected, the coupling element in turn being rigidly connected at the other end either to the first fastening element or to the second fastening element and the coupling element being designed to be shaft-shaped in the direction of the longitudinal axis, so that the web elements together with the coupling element are the two Fastening elements form a connecting element that connects one another in a sound-conducting manner, so that the web elements are designed so that they can enclose the coupling element in a clamp-like manner, or that the coupling element is designed so that it can engage in a force-fitting manner in the web elements, so that the web elements are designed in such a way are that in an in-situ state of the auditory ossicle prosthesis inserted in the human middle ear, when a force is applied to the web elements with a force component parallel to the longitudinal axis in the direction from the first fastening element to the second fastening element in situ, they each assume a position lying radially further from the longitudinal axis in sections and thus shorten the axial functional length between the first fastening element and the second fastening element in situ, the web elements each assuming a position in sections that is radially closer to the longitudinal axis when a force with a force component is introduced antiparallel to the longitudinal axis in the direction from the second fastening element to the first fastening element in situ and thus increase the axial functional length between the first fastening element and the second fastening element in situ, and that the web elements maintain their respective set radial position to the longitudinal axis in situ without the action of a force.

This allows the advantages of the above-described generic ossicle prosthesis, as described in reference [1], to be used in a relatively simple manner, although the change in length can take place with the prosthesis already placed in the middle ear, which is not the case with the prosthesis in reference [1]. or would only be possible with very significant changes.

Due to the shaft-shaped design, the coupling element is particularly easy to produce and mechanically relatively stable.

Due to the possibility of converting a mechanical movement within the surface of the head plate into an axial length adjustment, whereby the axial movement will ultimately always lead out of the head plate plane, a finely adjustable length adjustment can only be carried out in the auditory ossicle prosthesis according to the invention after insertion into the middle ear, i.e. in situ become. The change in length, i.e. the change in the distance between the head plate and the second fastening element at the other end of the prosthesis, occurs through an expansion out of the head plate plane into the depth (or vice versa).

The mechanism according to the invention is automatically guided within the head plate and therefore ensures uniform and, above all, symmetrical elongation even without additional measures. In contrast, the approaches of the solutions described in the prior art, in particular in reference [1], require that the user has to manipulate the prosthesis on both sides in order to bring about a symmetrical change in length.

Since the mechanism for adjusting the length is integrated into the head plate and installed with it, the auditory ossicle prosthesis according to the invention can also be manufactured with a very low overall height.

In addition, the mechanism according to the invention can be operated from above in the head plate. This is also a significant difference from the state of the art. For example, the prostheses according to reference [1] only allow complicated manipulation from the side, which requires a relatively large amount of space. The approach according to the invention, on the other hand, includes an extremely space-saving structure and is also suitable for endoscopic access.

Preferred embodiments of the invention

Particularly preferred embodiments of the auditory ossicle prosthesis according to the invention are characterized in that the web elements are designed in such a way that their respective set radial position relative to the longitudinal axis can be reversibly changed in situ by introducing a corresponding force.
In particular, the movement of the prosthesis parts during the adjustment process can be made reversible and the length of the prosthesis can not only be increased, but also shortened again.
The low force input ensures that surrounding middle ear structures are not damaged.
The sophisticated design of the head plate according to the invention enables optimal visibility during the procedure. The lightweight construction enables optimal sound transmission, especially in the high-frequency range.
The head plate design according to the invention made an optional coupling to the hammer handle (malleus) possible.
The design according to the invention was developed in such a way that there are no dead spaces. Therefore, no bio-films can form on the implant and implant-associated infections can develop.

Also preferred are embodiments of the auditory ossicle prosthesis according to the invention in which the coupling element is designed to be shaft-shaped in the direction of the longitudinal axis.
Shaft components of this type are particularly easy to produce and are mechanically relatively stable.

Further advantageous embodiments of the invention are characterized in that locking devices are present, which each cause mechanical resistance at one or more axial lengths of the connecting element when an axial force is introduced in the direction of the longitudinal axis onto the web elements and/or onto the coupling element.

The adjustment mechanism is therefore provided with locking points in order to achieve a defined axial length of the prosthesis and to fix this length.
The low force input ensures that surrounding middle ear structures are not damaged.
The locking devices enable optimal visibility during the procedure.
Resumption of the implant is possible during the procedure to ensure readjustment.

Advantageous developments of these embodiments are characterized in that the coupling element has, at least in an area facing the web elements during operation, ring-shaped grooves running around the circumference of the shaft and arranged at an axial distance from one another, into which radial projections of the web elements engage in the implanted state of the auditory ossicle prosthesis can, or that the web elements have grooves arranged at an axial distance from one another at least in an area facing the coupling element during operation, into which a radial projection of the coupling element) can engage in the implanted state of the auditory ossicle prosthesis.

In this groove solution, the web elements are preferably conically dimensioned so that there can be no play between the elements.

In preferred variants of these developments, the grooves can have defined, in particular identical, axial distances from one another.
This makes the coupling elements and web elements particularly easy to produce. In addition, the final length of the auditory ossicle prosthesis can be adjusted more precisely.

Also preferred are embodiments in which the coupling areas arranged within the head plate plane of the first fastening element are geometrically designed in such a way that over a force can be introduced onto the web elements with a force component parallel or anti-parallel to the longitudinal axis using an adjusting tool.

The in-situ length adjustment of the ossicle prosthesis can be achieved by manipulating the structure within the head plate. If you compress the structure with an instrument, the prosthesis lengthens. If you spread the structure, the length shortens. The adjustment tool serves as an implantation aid and in particular to operate the length adjustment mechanism. It can be designed as a minimally invasive, in particular endoscopic, instrument, preferably in the form of tweezers or forceps.

A change in length of the auditory ossicle prosthesis can in principle be achieved by plastic deformation of the connecting struts and/or by integrated joints.

A first class of embodiments of the auditory ossicle prosthesis according to the invention is characterized in that the web elements are designed to be mechanically rigid at least in sections, preferably completely.

This allows a certain flexibility or variability of the prosthesis to be achieved, as described in reference [3]. Advantageous with regard to a particularly high postoperative mobility of the prosthesis are further developments in which a large number of additional rotating elements adjacent to one another, preferably a ball joint chain, are used.

In a second class of alternative embodiments of the invention, the web elements are formed at least in sections from a plastic, flexible material, the plastic, flexible material of the web elements in particular having an elasticity ≥ 1%, preferably an elasticity ≥ 2%.

If the web elements are made of flexible material, the space and technical effort for the mechanical swivel joints can be saved. If the material of the bar elements has a flexibility of >1%, the prosthesis can be built particularly “tightly”, which also ensures that the prosthesis can follow the smallest “topographical” changes in the eardrum.

A first group of developments of this second class of embodiments, in which the plastic, flexible material of the web elements is a highly elastic material, preferably amorphous metal, in particular based on nickel, iron, cobalt or zirconium, and/or a nickel-titanium alloy and/or Memory metal, contains. The above-mentioned properties of flexibility combined with good rigidity for sound conduction can be optimally achieved with the materials mentioned.

In addition to its strength and excellent sound conduction properties, the material titanium in particular is also known to have excellent biocompatibility with the human middle ear. Embodiments of the invention in which the prosthesis or parts thereof, in particular one of the fastening elements, are made from a material with shape memory (=memory effect) or superelastic properties, preferably from Nitinol, which per se, for example, are advantageous with regard to a postoperative position adjustment the EP 1 961 400 B1 (=Reference [12]) is known.

In a second group of developments, the plastic, flexible material of the web elements can also contain highly elastic plastic, in particular high-strength elastic polymer, and/or elastic ceramic.

These materials provide ideal conditions for good sound transmission with high flexibility and good rigidity, but with a lower density.

Particularly advantageous are embodiments in which the coupling areas and the web elements are arranged flat within the head plate plane of the first fastening element before the initial introduction of a force onto the web elements with a force component parallel or anti-parallel to the longitudinal axis.

This enables a particularly compact structure of the auditory ossicle prosthesis according to the invention.

Preferred embodiments of the invention are characterized in that the web elements run curved and/or meandering and/or in zigzags between their respective coupling area and the coupling element.

A curved rather than a straight line increases the desired effect of local flexibility of the head plate and only locally limited deflection during smaller medial movements of the eardrum. This also makes it easier for the head plate to follow any post-operative changes to the eardrum.

In embodiments of the invention, radially outer, free end sections of the web elements can have atraumatic, non-pointed, free end edges that are radially outer with respect to the longitudinal axis and extend transversely to the direction of the longitudinal axis, or as atraumatic surfaces, preferably as closed surfaces or annular surfaces, in particular annular or elliptical , be trained. In this way, if a tilting moment occurs in the healing phase, which results in an increased force effect on the outer end sections, the surface pressure and the risk of extrusion can be reduced.

In further embodiments of the invention, the second fastening element is in the form of a plate, in particular as a curved plate, as a sleeve, as a loop, as a closed bell, in particular in the form of a hollow cylinder, as a single or multi-slotted bell or as a clip for mechanical connection to another member ossicular chain formed. Alternative embodiments can provide that the auditory ossicle prosthesis is coupled directly to the inner ear at its end carrying the second fastening element by means of perforation of the stapes footplate (=stapedectomy or stapedotomy) and/or by opening the human cochlea (=cochleotomy), in particular via a piston.

In addition to the postoperative position shift, another problem arises after the implantation of auditory ossicle prostheses: the middle ear of the human body represents a “half-open warehouse”. Any implant material that is introduced into the body as part of a reconstruction of the middle ear and its structures , experiences particular stress due to the fact that there is a contaminated and infected environment, which usually attacks the material. Since the aim of implanting an auditory ossicle prosthesis must always be to ensure that the implant remains in the patient's middle ear for as long as possible without complications, a prolonged attack on the material can lead to damage to the prosthesis and/or a local infection. Both consequences are intolerable. In order to permanently prevent damage to both the implantation material and the surrounding tissue, in a further particularly preferred embodiment of the invention, the surface of the auditory ossicle prosthesis is completely or at least partially covered with a biologically active coating, in particular a growth-inhibiting and/or a growth-promoting and/or one covered with an antibacterial coating. The head plate of the auditory ossicle prosthesis according to the invention should basically have a growth-promoting coating, while a second fastening element that leads directly into the inner ear and is designed in the form of a piston should rather have a growth-inhibiting coating.

Alternatively or additionally, in further embodiments, parts of the auditory ossicle prosthesis according to the invention can be made from a ceramic material. However, embodiments of the invention are also possible in which the prosthesis or parts thereof are made from biocompatible plastics, in particular silicone, polytetrafluoroethylene (PTFE) or fiber composite materials. With these materials, postoperative rejection reactions can also be prevented in most cases.

The scope of the present invention also includes a system comprising an auditory ossicle prosthesis constructed according to the invention of the type described above and an adjustment tool for manipulating the auditory ossicle prosthesis inserted in the middle ear of a patient in situ, wherein the adjustment tool can also serve as an implantation aid, and which is a minimally invasive, in particular endoscopic , instrument, preferably tweezers-like or pliers-like, is designed.

The advantage here is less trauma during the surgical implantation of the auditory ossicle prosthesis, as only a smaller opening of the eardrum, etc. is necessary.

Finally, the scope of the present invention also includes a method for implanting an auditory ossicle prosthesis according to the invention of the type described above, which is characterized in that the first fastening element, in particular the coupling areas within the head plate level, have structures made of memory metal, and that a force is applied the web elements are brought about by means of, preferably contactless, heating of the structures made of memory metal, in particular caused by light irradiation, for example laser radiation, and their resulting deformation.

This enables, in particular, a contactless application of force into the auditory ossicle prosthesis according to the invention, for example by means of heat radiation.

Detailed description of the invention based on the drawing

The schematic drawing shows exemplary embodiments of the invention, which are explained in more detail in the following description.

• 1 drei Abbildungen einer schematischen räumlichen Darstellung einer ersten Ausführungsform der erfindungsgemäßen Gehörknöchelchenprothese, davon zwei Abbildungen in einer Sicht schräg von oben mit Blickrichtung vom zweiten zum ersten Befestigungselement, wobei im Einzelnen dargestellt ist:
  1. a) die komplette Gehörknöchelchenprothese mit einem als einseitig offene, in radialer Richtung geschlossene Glocke gestalteten zweiten Befestigungselement,
  2. b) das als Kopfplatte gestaltete erste Befestigungselement der Gehörknöchelchenprothese von 1a) mit aus der Kopfplatten-Ebene heraus aufgerichteten Stegen
  3. c) eine Draufsicht in z-Richtung auf die Kopfplatten-Ebene des ersten Befestigungselements von 1b), wobei jedoch die Stegelemente vor dem Einleiten einer axialen Kraft noch vollständig in der Kopfplatten-Ebene angeordnet sind;
• 2 eine weitere Ausführungsform einer erfindungsgemäß gestalteten Gehörknöchelchenprothese, nämlich
  1. a) die komplette Gehörknöchelchenprothese in Blickrichtung schräg von oben vom zweiten zum ersten Befestigungselement,
  2. b) das als Kopfplatte gestaltete erste Befestigungselement der Gehörknöchelchenprothese von 2a) mit aus der Kopfplatten-Ebene heraus aufgerichteten Stegen schräg von unten in Blickrichtung vom ersten Befestigungselement in Richtung der aufgerichteten Stege,
  3. c) die Kopfplatte mit aufgerichteten Stegen von 2b) mit Blick darauf von der Seite senkrecht zur z-Richtung,
  4. d) ein Einstellwerkzeug zur Manipulation, insbesondere zur Längenverstellung der im Mittelohr eines Patienten eingesetzten Gehörknöchelchenprothese in situ;
• 3 eine Ausführungsform einer erfindungsgemäß gestalteten Gehörknöchelchenprothese, bei der das Verbindungselement zwischen dem ersten und zweiten Befestigungselement ein Schaft-förmiges Ankoppelelement ohne Rillen umfasst, wobei das zweite Befestigungselement als geschlitzte Glocke ausgeführt ist, nämlich
  1. a) die Gehörknöchelchenprothese mit seitlich am Ankoppelelement angepressten Stegen in Blickrichtung von der Seite senkrecht zur z-Richtung,
  2. b) die Gehörknöchelchenprothese von 3a) mit radial vom Ankoppelelement abgehobenen Stegen,
  3. c) die Gehörknöchelchenprothese von 3b) schräg von unten in Blickrichtung vom ersten Befestigungselement in Richtung zum zweiten Befestigungselement;
• 4 die Ausführungsform von 2a) in sukzessiven Stadien des Einsatzes des Einstellwerkzeugs von 2d), nämlich
  1. a) mit dem Einsatzwerkzeug in axialem Abstand in z-Richtung von der Gehörknöchelchenprothese,
  2. b) mit auf dem Einsatzwerkzeug aufgesetzter Kopfplatte der Gehörknöchelchenprothese, wobei die Greifarme des Einsatzwerkzeugs noch radial von der Außenkontur der Kopfplatte sowie vom Ankoppelelement beabstandet sind,
  3. c) wie 4b), jedoch mit radial an der Außenkontur der Kopfplatte sowie am Ankoppelelement angepressten Greifarmen des Einsatzwerkzeugs,
  4. d) wie 4c), jedoch mit axial vom zweiten Befestigungselement längs der z-Achse in Richtung auf das erste Befestigungselement tiefer am Ankoppelelement angreifenden Stegen,
  5. e) wie 4d), jedoch mit radial wieder von der Außenkontur der Kopfplatte sowie vom Ankoppelelement gelösten Greifarmen des Einsatzwerkzeugs; und
• 5 vier Abbildungen einer weiteren Ausführungsform mit Blickrichtung von der Seite senkrecht zur z-Achse auf die erfindungsgemäße Gehörknöchelchenprothese, deren Stegelement und Ankoppelelement hier parallel zur z-Richtung angeordnet sind und beide in das erste Befestigungselement münden, wobei das Ankoppelelement radial kraftschlüssig in Rillen des Stegelements eingreift, und zwar in vier unterschiedlichen Relativstellungen von Ankoppelelement und Steg, nämlich
  1. a) mit radialem Eingriff des Ankoppelelements in die dem ersten Befestigungselement nächstliegende Rille des Stegelements,
  2. b) wie 5a), jedoch mit radialem Eingriff des Ankoppelelements in die dem ersten Befestigungselement zweitnächste Rille des Stegelements,
  3. c) wie 5b), jedoch mit radialem Eingriff des Ankoppelelements in die dem zweiten Befestigungselement zweitnächste Rille des Stegelements,
  4. d) wie 5c), jedoch mit radialem Eingriff des Ankoppelelements in die dem zweiten Befestigungselement nächstliegende Rille des Stegelements.

Show it:

• 1 three images of a schematic spatial representation of a first embodiment of the auditory ossicle prosthesis according to the invention, two of which are images in a view obliquely from above with a viewing direction from the second to the first fastening element, with the following being shown in detail:
  1. a) the complete auditory ossicle prosthesis with a second fastening element designed as a bell that is open on one side and closed in the radial direction,
  2. b) the first fastening element of the auditory ossicle prosthesis designed as a head plate 1a) with webs erected from the head plate level
  3. c) a top view in the z direction of the head plate level of the first fastening element 1b) , however, the web elements are still completely arranged in the head plate plane before an axial force is introduced;
• 2 a further embodiment of an auditory ossicle prosthesis designed according to the invention, namely
  1. a) the complete auditory ossicle prosthesis viewed diagonally from above from the second to the first fastening element,
  2. b) the first fastening element of the auditory ossicle prosthesis designed as a head plate 2a) with webs erected from the head plate level diagonally from below in the direction of view from the first fastening element in the direction of the erected webs,
  3. c) the head plate with raised webs 2 B) looking at it from the side perpendicular to the z-direction,
  4. d) an adjustment tool for manipulation, in particular for adjusting the length of the auditory ossicle prosthesis inserted in the middle ear of a patient in situ;
• 3 an embodiment of an auditory ossicle prosthesis designed according to the invention, in which the connecting element between the first and second fastening elements comprises a shaft-shaped coupling element without grooves, the second fastening element being designed as a slotted bell, namely
  1. a) the auditory ossicle prosthesis with webs pressed onto the side of the coupling element when viewed from the side perpendicular to the z-direction,
  2. b) the auditory ossicle prosthesis from 3a) with webs raised radially from the coupling element,
  3. c) the auditory ossicle prosthesis from 3b) obliquely from below in the direction of view from the first fastening element towards the second fastening element;
• 4 the embodiment of 2a) in successive stages of using the adjustment tool 2d ), namely
  1. a) with the insert tool at an axial distance in the z direction from the auditory ossicle prosthesis,
  2. b) with the head plate of the auditory ossicle prosthesis placed on the insert tool, the gripping arms of the insert tool still being spaced radially from the outer contour of the head plate and from the coupling element,
  3. c) how 4b) , but with the gripping arms of the insert tool pressed radially onto the outer contour of the head plate and onto the coupling element,
  4. d) how 4c ), but with webs that engage deeper on the coupling element axially from the second fastening element along the z-axis in the direction of the first fastening element,
  5. e) how 4d ), but with the gripping arms of the insert tool detached radially from the outer contour of the head plate and from the coupling element; and
• 5 four illustrations of a further embodiment with a view from the side perpendicular to the z-axis onto the auditory ossicle prosthesis according to the invention, the web element and coupling element of which are arranged here parallel to the z-direction and both open into the first fastening element, the coupling element engaging radially in a force-fitting manner in grooves of the web element , namely in four different relative positions of the coupling element and web, namely
  1. a) with radial engagement of the coupling element in the groove of the web element closest to the first fastening element,
  2. b) how 5a) , but with radial engagement of the coupling element in the groove of the web element second closest to the first fastening element,
  3. c) how 5b) , but with radial engagement of the coupling element in the groove of the web element that is closest to the second fastening element,
  4. d) how 5c ), but with radial engagement of the coupling element in the second fastener The groove of the web element closest to the supply element.

The embodiments of the auditory ossicle prosthesis 10 according to the invention shown schematically in the figures of the drawing; 20; 30; 40 (or parts thereof) each have a first fastening element 11 at one end; 21; 31; 41, which is designed in the form of a flat head plate for mechanical contact with the eardrum and/or the hammer handle. At the other end of the auditory ossicle prosthesis 10; 20; 30; 40 sits a second fastening element 12; 22; 32; 42 for mechanically connecting the prosthesis to a link or parts of a link of the ossicular chain or to the inner ear. In between there is a connecting element 13 which connects the two fastening elements 11, 12 or 21, 22 or 31, 32 or 41, 42 to one another in a sound-conducting manner along a longitudinal axis z; 23; 33; 43 arranged.

The connecting element 13; 23; 33; 43 each includes web elements 14; 24; 34; 44, which - at least in sections - can be spread outwards more or less radially away from the longitudinal axis z and thereby the axial length of the auditory ossicle prosthesis 10; 20; 30; 40 more or less shorten.

The invention is distinguished from known generic auditory ossicle prostheses in that the web elements 14; 24; 34; 44 at one end directly into coupling areas 15; 25; 35; 45 of the first fastening element 11; 21; 31; 41 open within the head plate level and are movably but inextricably connected to it,
that all web elements 14; 24; 34; 44 with a coupling element 16; 26; 36; 46 are also movable and firmly but permanently connected during operation, the coupling element 16; 26; 36; 46 on the other hand either with the first
Fastening element 41 or with the second fastening element 12; 22; 32 is rigidly connected,
that the web elements 14; 24; 34; 44 together with the coupling element 16; 26; 36; 46 that the two fastening elements 11,12; 21.22; 31.32; 41.42 connecting element 13 that connects each other in a sound-conducting manner; 23; 33; 43 form,
that the web elements 14; 24; 34; 44 are designed such that they are in an in-situ state of the auditory ossicle prosthesis 10; 20; 30; 40 when a force is applied to the web elements 14; 24; 34; 44 with force component parallel to the longitudinal axis z in the direction of the first fastening element 11; 21; 31; 41 to the second fastening element 12; 22; 32; 42 in situ each assume a position that is radially further from the longitudinal axis z in sections and thus the axial functional length between the first fastening element 11; 21; 31; 41 and the second fastening element 12; 22; 32; 42 shorten in situ, with the web elements 14; 24; 34; 44 when a force is introduced with a force component anti-parallel to the longitudinal axis z in the direction of the second fastening element 12; 22; 32; 42 to the first fastening element 11; 21; 31; 41 in situ each assume a position in sections that is radially closer to the longitudinal axis z and thus the axial functional length between the first fastening element 11; 21; 31; 41 and the second fastening element 12; 22; 32; 42 enlarge in situ,
and that the web elements 14; 24; 34; 44 maintain their set radial position to the longitudinal axis z in situ without the action of a force.

The three views a) to c) of 1 represent various details of the auditory ossicle prosthesis 10:

1a) shows the complete auditory ossicle prosthesis 10 with a second fastening element 12 designed as a bell that is axially open on one side and closed in the radial direction, as well as a first fastening element 11 designed as a head plate, from which a web element 14 protrudes in the z direction onto the second fastening element 12 via a coupling area 15 and is in mechanical contact in the radial direction with the shaft-shaped coupling element 16 which opens into the second fastening element 12.

In this embodiment, the web elements 14 are designed so that they can enclose the coupling element 16 in a clamp-like manner. In its area facing the web elements 14, the coupling element 16 has grooves 16' which run in a ring shape around the circumference of the shaft and are arranged at an axial distance from one another, into which radial projections 14' of the web elements 14 engage. The projections 14', together with the grooves 16', form a locking device which, when an axial force is introduced in the direction of the longitudinal axis z onto the web elements 14 and/or onto the coupling element 16, each causes mechanical resistance at one or more axial lengths of the connecting element 13 .

1b) only shows the first fastening element 11 of the auditory ossicle prosthesis 10, designed as a head plate, with web elements 14 erected out of the head plate plane via the coupling areas 15.

1c ) shows a top view in the z direction of the head plate level of the first fastening element 11. Here the web elements 14 are still completely and flatly arranged within the head plate level. The head plate with the coupling Areas 15 and the web elements 14 can be designed as a one-piece bent sheet metal part.

In 2 a further embodiment of an auditory ossicle prosthesis 20 designed according to the invention is shown.

2a) again shows the complete auditory ossicle prosthesis 20 with a second fastening element 22, which is also designed as a closed bell, and a first fastening element 21 designed as a head plate, from which a web element 24 projects in the z direction onto the second fastening element 22 via a coupling area 25 and in the radial direction mechanical contact with the shaft-shaped coupling element 26 opening into the second fastening element 22. Here too, the web elements 24 are designed so that they can enclose the coupling element 26 in a clamp-like manner. The coupling element 26 in turn has grooves 26' which run around the circumference of the shaft and are arranged at an axial distance from one another, into which radial projections 24' of the web elements 24 engage and, together with the grooves 26', form a locking device.

2 B) shows - this time in a spatial view obliquely from below in the viewing direction from the first fastening element 21 in the direction of the erected webs 24 - again only the first fastening element 21 of the auditory ossicle prosthesis 20, designed as a head plate, with web elements 24 erected from the head plate plane over the coupling areas 25.

2c ) shows the first fastening element 21 from 2 B) looking at it from the side perpendicular to the z direction. The radial projections 24 'can be seen at the ends of the web elements 24 facing away from the head plate.

In 2d ) an adjustment tool 27 for in-situ length adjustment of the auditory ossicle prosthesis 20 can be seen in a spatial-schematic representation, the functionality of which can be seen in detail from the illustrations 4 is clarified.

The length adjustment of the auditory ossicle prosthesis 20 using this instrument occurs in that the web elements 24 move radially away from the z-axis when the shaft 26 is displaced in the axial direction. During assembly, the shaft can be pushed in laterally. The head plate 21 and the web elements 24 are welded together in this embodiment. The shaft with the grooves 26' ensures a defined length adjustment and a firm hold.

3 represents a further variant of an auditory ossicle prosthesis 30 according to the invention. Here, the connecting element 33 between the first fastening element 31 and the second fastening element 32, which is designed as a slotted bell, comprises a shaft-shaped coupling element 36 without grooves.

3a) shows, when viewed from the side perpendicular to the z-direction, the auditory ossicle prosthesis 30 with web elements 34 pressed laterally on the coupling element 36 via radial projections 34 ', while 3b) the auditory ossicle prosthesis 30 from 3a) in an operating position with web elements 34 lifted radially from the coupling element 36 in the direction of the arrow.

3c ) shows the auditory ossicle prosthesis 30 from 3b) obliquely from below in the viewing direction from the first fastening element 31 towards the second fastening element 32. Here you can clearly see how the control elements 34 protrude via the coupling areas 35 from the head plate level of the first fastening element 31 to the second fastening element 32.

The three web elements 34 arranged around the circumference hold the coupling element 36 by means of a clamping connection. If the head plate 31 is arched over by pressure from below, the web elements 34 tilt outwards and the clamping connection is released (temporarily). The position of the shaft can then be changed.

The five images a) to e) from 4 show the length adjustment of the embodiment of an auditory ossicle prosthesis 20 according to the invention 2a) in successive stages of use of the adjusting tool 27 from 2d ), namely 4a) the auditory ossicle prosthesis 20 with initially maximum axial length at a vertical distance in the z direction above the adjustment tool 27,
4b) the auditory ossicle prosthesis 20 with a head plate placed on the insert tool 27, the gripping arms of the insert tool 27 still being spaced radially from the outer contour of the head plate and from the coupling element,
4c ) the auditory ossicle prosthesis 20 as in 4b) , but with the gripping arms of the insert tool 27 pressed radially against the outer contour of the head plate and on the coupling element,
4d ) the auditory ossicle prosthesis 20 as in 4c ), but with webs that engage deeper on the coupling element axially from the second fastening element along the z-axis in the direction of the first fastening element, i.e. now with a smaller axial length and
4e) the shortened ossicle prosthesis 20 as in 4d ), but with radial again from the Outer contour of the head plate and the gripping arms of the insert tool 27 that are detached from the coupling element.

The two sets of radially inner and outer gripping arms of the instrument can be moved towards one another. This means that the implant is gripped by the head plate and the shaft at the same time. Each arm is constructed in two parts, with one part attached to the shaft and one part attached to the headstock. The two elements can be moved relative to each other. This allows the length of the implant to be adjusted. Ideally, the elements gripping the shaft remain in position relative to the elements in the middle ear. Only the head plate with arms changes its position when the instrument is operated. This means that the length of the implant changes without exerting pressure on the touching body parts in the middle ear (stapes, etc.).

The four views a) to d) of 5 Finally, in four different length settings, we present a further embodiment of the auditory ossicle prosthesis 40 according to the invention, in which the first fastening element 41 is connected to the second fastening element 42 via a bendable web element 44. The latter is firmly connected in a coupling area 45 - not explicitly shown in the drawing - to the first fastening element 41, which is designed as a flat head plate.

The web element 44 has, at its end facing the second fastening element 42, annular grooves 46' running around its circumference, into which a radial projection 44' of the coupling element 46, which runs essentially parallel to the web element 44 and is firmly anchored in the first fastening element 41, engages in a radially force-fitting manner. Together, the web element 44 and the coupling element 46 form a connecting element 43.

A ring element 47 is rigidly attached to the coupling element 46, but allows the web element 44 to pass through a ring-shaped opening, not specifically shown in the drawing, in the direction of the z-axis. During operation, the ring element 47 therefore exerts a radial force on the web element 44, so that the latter cannot radially avoid the coupling element 46 when it slides axially past it, but always remains nestled against the coupling element 46 during operation.

By introducing a force onto the web element 44 in the direction from the first fastening element 41 to the second fastening element 42, the web element 44 can be bent laterally, i.e. essentially in the radial direction, away from the z-axis, thereby increasing the distance between the first fastening element 41 and the second fastening element 42 and thus the axial length of the auditory ossicle prosthesis 40 shortened. If force is applied anti-parallel to this, the axial length can be increased.

So the axial length of the auditory ossicle prosthesis 40 can be varied within certain limits by bending the web element 44 laterally to different degrees. The stability of the construction is achieved by a holder via the coupling element 46, which is firmly anchored in the first fastening element 41, by means of a snap connection.

The four illustrations of the 4 show four different locking positions of the coupling element 46 and web element 44, namely
5a) with radial engagement of the coupling element 46 in the groove 46 'of the web element 44 closest to the first fastening element 41,
5b) How 5a) , but with radial engagement of the coupling element 46 in the second closest groove 46 'of the web element 44 to the first fastening element 41,
5c ) How 5b) , but with radial engagement of the coupling element 46 in the second closest groove 46 'of the web element 44 to the second fastening element 42, and
5d ) How 5c ), but with radial engagement of the coupling element 46 in the groove 46 'of the web element 44 closest to the second fastening element 42.

List of reference symbols:

10; 20; 30; 40

Auditory ossicle prosthesis

11; 21; 31; 41

first fastener

12; 22; 32; 42

second fastener

13; 23; 33; 43

connecting element

14; 24; 34; 44

Bridge elements

14'; 24'; 34'; 44'

Projections

15; 25; 35; 45

Coupling areas

16; 26; 36; 46

Coupling element

16'; 26'; 46'

grooves

27

Adjustment tool

47

Ring element

e.g

Longitudinal axis

Reference list

• [1] US 10 687 937 B2
• [2] DE 42 10 235 C1 ; EP 0 809 982 B1 ; US 6 387 128 B1
• [3] EP 1 181 907 B1
• [4] US 2004 / 0 162 614 A1
• [5] EP 1 833 424 B1
• [6] EP 1 972 307 B1
• [7] EP 3 311 773 B1
• [8] DE 10 2007 041 539 B4
• [9] EP 2 238 946 B1
• [10] EP 2 601 909 B1
• [11] EP 3 130 315 B1
• [12] EP 1 961 400 B1

Publications considered for the assessment of patentability:

• [1] US 10,687,937 B2
• [2] DE 42 10 235 C1 ; EP 0 809 982 B1 ; US 6,387,128 B1
• [3] EP 1 181 907 B1
• [4] US 2004 / 0 162 614 A1
• [5] EP 1 833 424 B1
• [6] EP 1 972 307 B1
• [7] EP 3 311 773 B1
• [8th] DE 10 2007 041 539 B4
• [9] EP 2 238 946 B1
• [10] EP 2 601 909 B1
• [11] EP 3 130 315 B1
• [12] EP 1 961 400 B1

Claims (13)

Auditory ossicle prosthesis (10; 20; 30; 40), which replaces or bridges at least one link or parts of a link of the auditory ossicle chain, the auditory ossicle prosthesis (10; 20; 30; 40) having at one end a flat head plate for mechanical contact with the eardrum and/or a first fastening element (11; 21; 31; 41) formed on the hammer handle and at its other end a second fastening element (12; 22; 32; 42) for mechanical connection to a link or parts of a link of the ossicular chain or with the inner ear and a connecting element (13; 23; 33; 43) which connects the two fastening elements (11,12; 21,22; 31,32; 41,42) to one another in a sound-conducting manner along a longitudinal axis (z), and wherein the connecting element (13; 23; 33; 43) has web elements (14; 24; 34; 44) which - at least in sections - can be spread outwards more or less radially away from the longitudinal axis (z) and thereby the axial length of the auditory ossicle prosthesis ( 10; 20; 30; 40) shorten more or less, characterized in that the web elements (14; 24; 34; 44) at one end directly into coupling areas (15; 25; 35; 45) of the first fastening element (11; 21; 31; 41) within the head plate level open and are movably but inseparably connected to these, that all web elements (14; 24; 34; 44) are also movably and firmly but releasably connected to a coupling element (16; 26; 36; 46) during operation, the coupling element (16; 26; 36; 46) in turn is rigidly connected at the other end either to the first fastening element (41) or to the second fastening element (12; 22; 32) and the coupling element (16; 26; 36; 46) is shaft-shaped in the direction of the longitudinal axis (z) is designed so that the web elements (14; 24; 34; 44) together with the coupling element (16; 26; 36; 46) which the two fastening elements (11,12; 21,22; 31, 32; 41, 42) sound-conducting connecting elements (13; 23; 33; 43) form that the web elements (14; 24; 34; 44) are designed so that they can grip the coupling element (16; 26; 36) in a clamp-like manner in a force-fitting manner, or that the coupling element (46) is designed in such a way that it can engage in a force-fitting manner in the web elements (44) so that the web elements (14; 24; 34; 44) are designed in such a way that they are in an in-situ state of the auditory ossicle prosthesis (10; 20; 30; 40) inserted in the human middle ear when a force is applied to the bar elements (14; 24; 34 ; 44) with a force component parallel to the longitudinal axis (z) in the direction from the first fastening element (11; 21; 31; 41) to the second fastening element (12; 22; 32; 42) in situ, in sections one radially further from the longitudinal axis (z) assume a lying position and thus shorten the axial functional length between the first fastening element (11; 21; 31; 41) and the second fastening element (12; 22; 32; 42) in situ, the web elements (14; 24; 34; 44) when a force is introduced with a force component anti-parallel to the longitudinal axis (z) in the direction of the second fastening element (12; 22; 32; 42) to the first fastening element (11; 21; 31; 41) in situ in sections assume a position that is radially closer to the longitudinal axis (z) and thus the axial functional length between the first fastening element (11; 21; 31; 41) and the second fastening element (12; 22; 32; 42) in situ, and that the web elements (14; 24; 34; 44) maintain their set radial position to the longitudinal axis (z) in situ without the action of a force. Auditory ossicle prosthesis Claim 1 , characterized in that the web elements (14; 24; 34; 44) are designed such that their respective set radial position relative to the longitudinal axis (z) can be reversibly changed in situ by introducing a corresponding force. Auditory ossicle prosthesis according to one of the preceding claims, characterized in that locking devices are present which, when an axial force is introduced in the direction of the longitudinal axis (z), onto the web elements (14; 24; 34; 44) and/or onto the coupling element (16; 26 ; 36; 46) each cause mechanical resistance at one or more axial lengths of the connecting element (13; 23; 33; 43). Auditory ossicle prosthesis Claim 3 , characterized in that the coupling element ment (16; 26; 36) has, at least in an area facing the web elements (14; 24; 34) during operation, ring-shaped grooves (16';26') running around the circumference of the shaft and arranged at an axial distance from one another, in which radial projections (14';24';34') of the web elements (14; 24; 34) can engage in the implanted state of the auditory ossicle prosthesis (10; 20; 30), or that the web elements (44) at least in one of the coupling elements during operation (46) have grooves (46') arranged at an axial distance from one another, into which a radial projection (44') of the coupling element (46) can engage in the implanted state of the auditory ossicle prosthesis (40). Auditory ossicle prosthesis Claim 4 , characterized in that the grooves (16';26';46') have defined, preferably identical, axial distances from one another. Auditory ossicle prosthesis according to one of the preceding claims, characterized in that the coupling areas (15; 25; 35; 45) arranged within the head plate plane of the first fastening element (11; 21; 31; 41) are geometrically designed in such a way that a force can be introduced via them on the web elements (14; 24; 34; 44) with force components parallel or anti-parallel to the longitudinal axis (z) can be done in situ by means of an adjusting tool (27). Auditory ossicle prosthesis according to one of the Claims 1 until 6 , characterized in that the web elements (14; 24; 34; 44) are designed to be mechanically rigid at least in sections, preferably completely. Auditory ossicle prosthesis according to one of the Claims 1 until 6 , characterized in that the web elements (14; 24; 34; 44) are formed at least in sections from a plastic, flexible material, and that the plastic, flexible material of the web elements (14; 24; 34; 44) in particular has an elasticity ≥ 1 %, preferably an elasticity ≥ 2%. Auditory ossicle prosthesis Claim 8 , characterized in that the plastic, flexible material of the web elements (14; 24; 34; 44) is highly elastic material, preferably amorphous metal, in particular based on nickel, iron, cobalt or zirconium, and / or a nickel-titanium alloy and / or memory metal. Auditory ossicle prosthesis Claim 8 , characterized in that the plastic, flexible material of the web elements (14; 24; 34; 44) contains highly elastic plastic, in particular high-strength elastic polymer, and / or elastic ceramic. Auditory ossicle prosthesis according to one of the preceding claims, characterized in that the coupling areas (15; 25; 35; 45) and the web elements (14; 24; 34; 44) are before the initial introduction of a force onto the web elements (14; 24; 34; 44) with a force component parallel or anti-parallel to the longitudinal axis (z) are arranged flat within the head plate plane of the first fastening element (11; 21; 31; 41). Auditory ossicle prosthesis according to one of the preceding claims, characterized in that the web elements (14; 24; 34; 44) between their respective coupling area (15; 25; 35; 45) and the coupling element (16; 26; 36; 46) are curved and / or meandering and/or zigzag. System comprising an auditory ossicle prosthesis (10; 20; 30; 40) according to one of Claims 6 until 12 and an adjusting tool (27) for manipulating the ossicle prosthesis (10; 20; 30; 40) inserted in the middle ear of a patient in situ, characterized in that the adjusting tool (27) is a minimally invasive, in particular endoscopic, instrument, preferably tweezers-like or pliers -like, trained.

Images