DE102011008120B3 - Incus-stapes-rail for use during repairing of defects of elongated extension unit of incus, has ridge provided on convex surface, where form of rail corresponds to semi-tube that is curved, during longitudinal extension of rail - Google Patents

Abstract

The rail has a ridge provided on a convex surface, where form of the rail corresponds to a semi-tube that is curved, during longitudinal extension of the rail. The ridge enables engagement of the rail via forceps, transportation of the rail into a middle ear and positioning of the rail between incus remaining portion and stapes. The rail is made of biocompatible material, which is decomposed in a biological manner. The rail is designed in a transparent manner. The rail is impermeable to light and filled with alloplastic material and/or reinforcement unit.

Description

The invention relates to a to be implanted in the middle ear splint, which is intended to contribute to a hearing improvement in which it serves in a defect of the long process of the incus process of reconstruction of the ossicular chain by autogenous, allogenic, xenogeneic tissue and / or alloplastic material.

State of the art:

The ossicles (hammer, anvil, stirrup) transmit the sound from the eardrum to the inner ear as a so-called ossicular chain. A defect in the auditory ossicles can lead to a possibly pronounced hearing loss. If the long extension of the anvil is destroyed, the anvil remains are often removed and replaced by an alloplastic ossicle prosthesis or the anvil remains is used after its processing to increase the stirrup again. However, these methods do not always achieve sufficiently good hearing. In addition, a dislocation of the Interponats can lead to a renewed increase in conductive hearing loss.

Another reconstruction principle is bridging the defect between anvil rest and stirrup. This preserves the architecture and physiological function of the ossicular chain. For bridging, bone and cartilage can be used for very small defects. Angular dentures and cement have proven to be particularly suitable, with which even larger defects can be bridged and with which often a very good hearing function is achieved. Disadvantage in particular when using an angle prosthesis is that for attachment to the anvil a sufficiently large remainder of the long anvil process must be present. Even if cement is used alone, the defect to be bridged should not be too large, since otherwise the cement that has not yet hardened into the middle ear can run or slip uncontrollably. In order to enable reconstruction with cement even for large defects, the use of a platinum wire as a supporting skeleton for the cement was described. The use of a wire requires that a custom wire be made during the operation. However, this method prolongs the duration of the operation and has weaknesses in the reproducibility of the results. In addition, a new operation on the ossicles increased risk of injury to the stapes and thus for an inner ear damage, as the wrapped around the stirrup platinum wire is covered by the cement and thus manipulation difficult.

As a further way to bridge large defects with cement, the repeated application of cement has been described. This procedure prolongs the duration of the operation, leads to an increased consumption of material and thus to additional costs.

in the US 2009/0198334 A1 a helical titanium prosthesis is described, which represents a modified form of the previously known angular prosthesis, which is to serve to bridge the destroyed long incus process. As a possible option, the additional covering of the prosthesis with cement is described. Basically, it should be noted that other angular prostheses could be used as a supporting skeleton for cement. Since already the actual prosthesis takes over the function of the sound transmission, an advantage is not apparent by an additional cement sheath. On the contrary, as already stated for the use of the platinum wire, the cement sheath in a new operation on the ossicles is a higher risk of damage to the stirrup and thus the inner ear likely. In addition, for the spiral prosthesis there must be a sufficiently large remainder of the long incus process, over which one end of the prosthesis can be pushed.

in the US 7794468 B2 Apparatuses are shown with the help of which the targeted introduction of primarily cement between the ossicles to be connected should be facilitated. The apparatus consists of a tube, which is connected via a connecting tube with a reservoir for the cement to be introduced. It is envisaged that only after the tube has been positioned between the auditory ossicles to be connected will the cement be filled from the reservoir via the connecting tube into the tube for hardening thereafter. However, a manual filling of the tube is also possible.

• 1.) Wird der Apparat während der Aushärtung entfernt, droht eine Zerstörung der Zementbrücke, wenn Zement als Folge von Adhäsionskräften an der Röhre des Apparates haften bleibt. Wird dagegen mit der Entfernung des Apparates bis zur Aushärtung des Zements gewartet, muss während dieser Phase der Apparat vollkommen ruhig gehalten werden, was nicht immer gewährleistet werden kann. Kommt es während der Aushärtungsphase zu einer festen Verbindung des Zements mit dem Apparat, kann es beim Herausnehmen des Apparates nicht nur zu einer Zerstörung der Zementbrücke, sondern durch die entstehenden Zugkräfte an den mit der Zementbrücke fest verbundenen Gehörknöchelchen zu einer Dislokation der Gehörknöchelchen oder zu einer Schädigung des an das Innenohr grenzenden Steigbügels und damit im ungünstigsten Fall sogar zu einer Innenohrschädigung kommen.
• 2.) Der Apparat ist vornehmlich für die Applikation von Zement in noch dünnflüssigem Zustand ausgelegt. Für einen regenerativen Therapieansatz, der zu einer knöchernen Reparatur des Defektes führen soll, ist evtl. die Anwendung von Gewebe notwendig, welches nicht über einen dünnen Verbindungsschlauch zum Zielort gepresst werden kann.

Disadvantages of this technical solution are:

• 1.) If the apparatus is removed during curing, the cement bridge may be destroyed if cement adheres to the apparatus tube as a result of adhesive forces. If, on the other hand, it is waited with the removal of the apparatus until the cement hardens, the apparatus must be kept completely still during this phase, which can not always be guaranteed. If it comes during the curing phase to a firm connection of the cement to the apparatus, it may be when removing the apparatus not only to a destruction of the cement bridge, but by the resulting tensile forces on the firmly attached to the cementum ossicles dislocation of the ossicles or to a Damage to the adjacent to the inner ear stirrup and thus even come to an inner ear damage in the worst case.
• 2.) The apparatus is designed primarily for the application of cement in a still fluid state. For a regenerative therapy approach, which should lead to a bony repair of the defect, the application of tissue may be necessary, which can not be pressed over a thin connecting tube to the target site.

Essence of the invention:

The object of the invention is to develop a rail implantable in the middle ear for the dimensionally stable, secure introduction of alloplastic materials, preferably cement, which serve to bridge defects of the long anvil process. In addition to this application, this splint can also be used for the dimensionally stable, safe introduction of autogenous, allogeneic and xenogeneic tissue which, in addition to the reconstruction, can also serve for the regeneration of defects of the long anvil process.

According to the invention the object is achieved in that an anvil stirrup rail with the shape of a half-tube, which is bent convexly in its longitudinal extent, is used. This anvil stirrup rail bridges the defect existing between the anvil rest and the stirrup, together with the tissue and / or alloplastic material filled in the half-tube.

In the anvil stirrup rail according to the invention, a burr is arranged centrally on the outer, convex surface of the half-tube curved in its longitudinal extension. This ridge is intended to facilitate the positioning of the anvil stirrup rail in the middle ear.

The trough-shaped interior of the anvil stirrup rail is filled prior to introduction into the middle ear with the reconstruction or regeneration serving tissue and / or alloplastic material. The anvil stirrup rail remains in the middle ear after insertion.

Embodiment:

The invention will be explained in more detail below with reference to an embodiment. It represents in a drawing the

1 the anvil stirrup rail having a ridge centrally located along the outer convex surface and

2 the anvil stirrup rail having a ridge centered along the outer convex surface, the ridge extending over only a portion of the surface,
represents.

According to 1 The anvil stirrup rail according to the invention has the shape of a half-tube convexly curved in its longitudinal extent, on the convex surface of which a ridge running along the center line is located.

The burr is used for problem-free gripping of the anvil stirrup rail by means of a suitable aid, preferably a micro Ohrzängchen. This facilitates the transport of the anvil stirrup rail filled with tissue and / or alloplastic material into the middle ear and its positioning between anvil rest and stirrup. Additionally, gripping the anvil stirrup rail on the ridge prevents pressure from being exerted on the side edges of the rail and thereby pushing tissue and / or material out of the groove.

According to 2 the burr extends only over part of the outer convex surface of the anvil stirrup rail. This can be advantageous if pressure damage to the taste nerve passing through the middle ear appears possible through the burr extending over the entire convexity of the anvil stirrup rail. The anvil stirrup rail is made of machinable, biocompatible material which is preferably biodegradable. The material is preferably transparent in its structure.

Sites:

• • US 7794468 B2
• • US 2009/0198334 A1
• • Hüttenbrink KB et al. Titanium Angular Clip: a new prosthesis for the long process of the incus. Otol Neurotol 2009; 30: 1186-1190.
• • Elsheikh MN et al. Physiologic restablishment of ossicular continuity during excision of retraction pockets. Arch Otolaryngol Head Neck Surg 2006; 132: 196-199.
• • Baglam T et al. Incudostapedial rebridging ossiculoplasty with bone cement. Otolaryngol Head Neck Surg 2009; 141: 243-246.

Claims (3)

Anvil stirrup rail, characterized in that it is formed as a convexly curved in its longitudinal extension half tube and on its convex outer surface side longitudinally and centrally a ridge is arranged, which gripping her facilitated for transport into the middle ear and their positioning between anvil rest and stirrups. Anvil stirrup rail according to claim 1, characterized in that it consists of a biocompatible material. Anvil stirrup rail according to claim 2, characterized in that the biocompatible material can be processed in its shape.

Images