DE102010052914B4 - Endoprosthesis and use of the endoprosthesis - Google Patents

Abstract

Endoprosthesis having a base body (12), which consists of a biocompatible material, wherein within the base body (12) at least one channel (16, 18, 20) and at least one cavity (14) are arranged, characterized in that the at least one channel (16, 18, 20) in a region close to the outer surface (12b) of the base body (12) has a different surface finish and / or a different volume structure than the rest of the channel (16, 18, 20).

Description

The present invention relates to an endoprosthesis with a base body, which consists of a biocompatible material, wherein within the body at least one channel and at least one cavity are arranged as well as uses of an endoprosthesis with at least one channel and / or at least one cavity.

An endoprosthesis is an implant made of a foreign material, which is modeled on a damaged part of the body, is introduced into the interior of the body and remains there permanently. Endoprostheses z. B. as hip joints, knee joints, shoulder joints, ankle joints, finger joints, skull plates or dental implants.

The permanent anchoring of the endoprosthesis is carried out by the body of the patient newly formed bone substance, which connects the endoprosthesis with the body's own bone. Endoprostheses can also be connected to the endogenous bone using bone cement.

Conventional endoprostheses are conventionally made by casting, forming or machining processes.

During surgery to insert the endoprosthesis, drains are usually used to drain blood and sacs, ending in various wound layers and leading to a vacuum bottle in which these fluids are collected. These drains must be installed consuming and interfere with the surgical procedure.

After the onset of the endoprosthesis can cause complications, such. B. in the form of bruising, rebleeding, nerve injury, wound infection, penetration of germs into the wound and associated bone conduction and related pain. However, the delivery of drugs with curative or pain relief to these sites is problematic, so that in many cases further operations must be performed.

The US 2010/0 145 469 A1 relates to a bioceramic implant containing at least one bioactive substance. In addition, this document describes an apparatus and a method for producing such a bioceramic implant. Here, a "cold" rapid prototyping method by means of 3D printing is proposed in which the powder layers are selectively bound by applying a liquid, and for complex implant structures and CAD data can be integrated into the manufacturing process.

The US 2010/0 042 214 A1 discloses an orthopedic implant which is implantable at a desired location of a human body part and which is configured to deliver at least one therapeutic agent to the human body part. For this purpose, the implant contains a reservoir and a plurality of channels, The reservoir serves to receive the at least one therapeutic agent, while the channels are designed so that they can forward the therapeutic agent from the reservoir to a treatment site of the human body part.

In the US 5,376,123 An adaptable shaft for an endoprosthesis is described. The shaft is mechanically connected to the bone with a filler material. In addition, this filling material is separated from the bone by the biocompatible wall of a sealed chamber.

From the WO 2008/035 089 A1 Finally, it is known to equip an implant with sensors for receiving various parameters. These sensors may also be coupled to a drug reservoir also located in the implant to control the delivery of a drug to the surrounding tissue.

In view of the aforementioned prior art, the present invention seeks to provide an endoprosthesis, which further reduces the risk of revision surgery and to provide a use of such endoprosthesis.

This object is achieved by the features specified in the patent claims 1, 14 and 15.

Further developments of the invention are specified in the subclaims.

According to the invention, the at least one channel arranged in the endoprosthesis has a different surface quality (eg greater surface roughness) or a different volume structure than the rest of the channel in a region close to the outer surface, so that the anchoring strength of the endoprosthesis in the surrounding bone is further increased and the risk of revision surgery is further reduced.

Due to the arrangement and shape of the at least one cavity and the arrangement and shape of the at least one channel may have different uses or different positions the patient treated with the endoprosthesis.

Due to the formation of channels with different sized cross-section of the different use of the channels, z. As for the drainage of wound water, for drug delivery or endoscopy, be met.

In an advantageous development of the embodiment, the at least one channel is designed to widen at an end section towards the outer surface, whereby the anchoring strength of the endoprosthesis can be increased.

In a further advantageous embodiment, a container with a container contents is accommodated in the cavity or channel, whereby it is possible to supply the container contents to the body in the region of the endoprosthesis in a simple manner. Preferably, the container is a drug reservoir for delivery of a medicament.

In another embodiment, a sensor is arranged in the cavity or channel with which the anchoring strength of the endoprosthesis or the hardening state of bone cement can be determined.

By using a generative manufacturing process (also known as additive manufacturing process, also called rapid prototyping) for the production of the endoprosthesis this can also have a complicated geometric shape, the endoprosthesis can be produced with high dimensional accuracy.

A particular advantage of an endoprosthesis formed with at least one channel and / or at least one cavity is in a use for endoscopy, in that an endoscope for assessing the healing process is introduced via the at least one channel or cavity of the endoprosthesis.

A further advantage of an endoprosthesis formed with at least one channel and / or at least one cavity is the use for drainage of wound water and blood at an implantation site and / or for the delivery of a medium for the dissolution of bone cement or the regression of bone material at the implantation site in preparation for a revision surgery.

The invention will be explained in more detail using an exemplary embodiment with reference to the drawings. Show:

1 a sectional view of an embodiment of an endoprosthesis according to the invention, and

2 a sectional view of the endoprosthesis of 1 with inserted drug reservoir.

As in 1 is shown has an endoprosthesis 10 a basic body 12 on, which consists of a biocompatible material. As a material titanium, a titanium alloy, z. TiAl6V4 or TiAl6Nb7, a cobalt-chromium alloy, e.g. B. CoCrMo, ceramic or plastic, z. As polyethylene used. The main body 12 is simulated to a damaged body part and has a thickened central region in the embodiment shown 12a on.

Within the body 12 in the thickened area 12a is a cavity 14 arranged. The cavity 14 stands with a first main channel 16 in contact, extending to an outer surface 12b of the basic body 12 extends. The first main channel 16 points one from the outside surface 12b extending vertical section 16a and a bent section 16b leading to the cavity 14 leads, on.

The cavity 14 also has a second main channel 18 in conjunction, meandering from the cavity 14 to the outer surface 12b of the basic body 12 extends.

A group of branch channels 20 extends from the second main channel 18 and the cavity 14 to the outer surface 12b of the basic body 12 , The first main channel 16 , the second main channel 18 and the branch channels 20 represent the at least one channel in the following description.

As in 1 shown are the first main channel 16 , the second main channel 18 and the branch channels 20 formed with a preferably circular cross-section and preferably each have different diameter. In a modified embodiment, the cross sections of the channels 16 . 18 . 20 square, rectangular or oval or have another desired cross-sectional shape. The channels can also be the same diameter.

The number, shape and course of the at least one channel 16 . 18 . 20 and / or the at least one cavity 14 is the field of application of the respective endoprosthesis 10 customized.

The endoprosthesis 10 according to the embodiment shown has the following advantages.

Through the channels 16 . 18 . 20 it is possible to drain blood and wound water at the wound layers in the region of the implantation site or to suck it out using a vacuum. There is also the possibility of endoscopy via the channels 16 . 18 . 20 to assess the healing process in the connection of the endoprosthesis with the body's own bone.

Even in case of a required revision surgery can be done by an endoscopy over the channels 16 . 18 . 20 Information about the connection status of the endoprosthesis 10 be obtained with the body's own bone. Besides, the channels can 16 . 18 . 20 be used in preparation for a revision operation for the supply of a medium, the dissolution of bone cement or regression of bone material at the implantation site of the endoprosthesis 10 leads.

Since newly formed bone substance during the connection process of the endoprosthesis with the body's own bone in the channels 16 . 18 . 20 grows, is an increased anchoring strength of the endoprosthesis 10 achieved in the body of the patient. To the anchoring strength of the endoprosthesis 10 is to increase further, is an end portion of the at least one channel 16 . 18 . 20 to the outer surface 12b of the basic body 12 towards conically widening formed.

In one of the outer surface 12b of the basic body 12 nearby area of the at least one channel 16 . 18 . 20 its wall has a larger surface roughness than the rest of the wall of the respective channel 16 . 18 . 20 , In another embodiment, that of the outer surface 12b of the basic body 12 nearby area a different volume structure than the rest of the wall of the respective channel 16 . 18 . 20 , For example, the volume structure may have the structure similar to that of a sponge or coral. The length of the channel 16 . 18 . 20 in the embodiment described with the range of greater surface roughness or other volume structure is z. B. preferably up to 20 mm. Due to the larger surface roughness or other bulk structure of the material in the outer surface 12b nearby area of the wall of the canal 16 . 18 . 20 can the anchoring strength of the compound of the endoprosthesis 10 be further improved with the body's bone, without affecting the flow of fluids in the remaining part of the channel 16 . 18 . 20 is changed.

By the delivery of bone cement or a bioabsorbable filler through the channels 16 . 18 . 20 After implantation in areas which are difficult or impossible to access from the outside after implantation, the fixation of the endoprosthesis can take place 10 be further improved by the contact surface between the endoprosthesis 10 and the body's bone is increased and thus the surface pressure is reduced to the bone of the patient. In addition, fit inaccuracies can be compensated, and a loosened endoprosthesis can be fixed.

2 shows an embodiment of an endoprosthesis 10 in which in the cavity 14 a container 22 with a container contents, which may be solid, liquid or gaseous, is used. In the embodiment shown, the container 22 a drug reservoir containing a drug as a container content through the channels 16 . 18 . 20 the newly forming or newly formed bone substance or the body's own bone of the patient in the implant area supplies.

The drug is a means of infection prevention, pain relief, promoting wound healing and / or the formation of new bone. The drug may also include a combination of said agents. The container 22 and / or the container contents in this embodiment are such that the medicament is delivered evenly over a certain period of time.

In a modified embodiment, the container 22 a drug that counteracts a drop in blood pressure and / or an oxygen saturation drop. These phenomena are known to occur in the use of bone cement in many cases when the bone cement is in the polymerization and in this case is in particular shortly before the end of curing.

The container 22 is in a modified embodiment instead of in the cavity 14 in one of the channels 16 . 18 . 20 arranged.

In another embodiment is in the cavity 14 or in one of the channels 16 . 18 . 20 a sensor for determining the anchoring strength of the endoprosthesis 10 or a sensor for determining the curing state of the bone cement arranged.

The container 22 and the corresponding sensor are in a further embodiment so within the body 12 arranged that they interact. So z. For example, the sensor for determining the curing state of the bone cement for the timely release of drugs against blood pressure drop or oxygen saturation waste from the container 22 be used. In a modified embodiment, when a loosening condition of the end prosthesis is detected by the sensor, a means for disintegrating the bone cement is delivered in preparation for a revision operation.

In one embodiment, the container is or are 22 and / or the container contents such that a time of delivery of the container contents in the at least one cavity 14 and / or the at least one channel 16 . 18 . 20 from a location outside the body of the patient is controllable.

To produce the endoprosthesis, a generative production method, in particular jet melting (energy jet melts such as laser beam melts or electron beam melts) or laser sintering, is preferably used. Here are first CAD data of the endoprosthesis 10 with the at least one channel 16 . 18 . 20 and / or the at least one cavity 14 created. This is followed by a computer-assisted layer-by-layer construction of the endoprosthesis 10 made of a powdery biocompatible material using the CAD data, wherein each powder layer is brought to the melting or sintering by heating before applying the next powder layer for fixing with the underlying layer.

By using such a generative manufacturing method, it is possible to produce endoprostheses with high geometric complexity, with a desired surface quality and high accuracy.

In another embodiment, the endoprosthesis 10 by a casting process, for. As lost wax process produced.

In a further embodiment, in a conventionally produced endoprosthesis by a material-removing manufacturing process, the at least one cavity 14 and / or the at least one channel 16 . 18 . 20 brought in. Such a material-removing manufacturing process is z. B. drilling or spark erosion. A cavity 14 can z. B. be prepared by drilling such that a bore is introduced into the endoprosthesis and the bore then by a part, for. B. a plug, which preferably consists of the same material as the endoprosthesis is closed.

The invention is not limited to the described embodiments.

In another embodiment, the base body 12 only at least one cavity 14 without connection to the outer surface 12b of the basic body 12 on.

In a further embodiment, the base body 12 only at least one channel 16 . 18 . 20 without formation of a cavity 14 on.

The shape, the number and the course of the channels 16 . 18 . 20 as described or illustrated, are not limited to the embodiment described, but may differ from these.

In a further embodiment, channels extend in a star shape from the cavity 14 or from another channel to the outside surface 12b of the basic body 12 ,

In another embodiment, the main body 12 made of a non-bloc compatible material, wherein the outer surface of the body 12 coated with a biocompatible layer, for example of proteins. Further, in this embodiment, walls of the channels and cavity bounding areas are coated with the biocompatible layer.

In a further embodiment, the wall of the at least one channel 16 . 18 . 20 and / or the wall of the at least one cavity 14 a different surface quality, in particular a lower surface roughness than the outer surface 12b of the basic body 12 on.

Claims (15)

Endoprosthesis with a basic body ( 12 ), which consists of a biocompatible material, wherein within the body ( 12 ) at least one channel ( 16 . 18 . 20 ) and at least one cavity ( 14 ), characterized in that the at least one channel ( 16 . 18 . 20 ) in one of the outer surfaces ( 12b ) of the basic body ( 12 ) has a different surface finish and / or volume structure than the rest of the channel ( 16 . 18 . 20 ). Endoprosthesis according to claim 1, characterized in that in one of the outer surface ( 12b ) near the at least one channel ( 16 . 18 . 20 ) the volume structure of the channel ( 16 . 18 . 20 ) is formed as a structure similar to that of a sponge or a coral. Endoprosthesis according to one of claims 1 or 2, characterized in that the basic body ( 12 ) has a first channel extending from the outer surface ( 12b ) of the basic body ( 12 ) to the outer surface ( 12b ) of the basic body ( 12 ) extends at a different location and / or a second channel ( 16 . 18 . 20 ) extending from the cavity ( 14 ) to the outer surface ( 12b ) of the basic body ( 12 ) and / or a third channel ( 20 ) extending from the first channel or from the second channel ( 16 . 18 ) to the outer surface ( 12b ) of the basic body ( 12 ). Endoprosthesis according to one of claims 1 to 3, characterized in that the basic body ( 12 ) has at least two channels, which have a different sized and / or differently shaped cross-section. Endoprosthesis according to one of claims 1 to 4, characterized in that the at least one channel ( 16 . 18 . 20 ) at one end portion to the outer surface ( 12b ) is formed towards widening. Endoprosthesis according to one of claims 1 to 5, characterized in that in the at least one channel ( 16 . 18 . 20 ) and / or the at least one cavity ( 14 ) a container ( 22 ) is arranged with a container contents and / or a sensor or are. Endoprosthesis according to claim 6, characterized in that the container ( 22 ) is a drug reservoir and the sensor is a sensor for determining the anchoring strength of the endoprosthesis or a sensor for determining the hardening state of the bone cement. Endoprosthesis according to claim 7, characterized in that the medicament reservoir contained in the drug is a means for infection prevention, for pain relief, for promoting wound healing and / or for the formation of new bone substance. Endoprosthesis according to claim 7 or 8, characterized in that the medicament reservoir contains a medicament which counteracts a drop in blood pressure and / or an oxygen saturation drop. Endoprosthesis according to one of claims 1 to 9, characterized in that the endoprosthesis ( 10 ) consists of titanium, a titanium alloy, a cobalt-chromium alloy, ceramic or a plastic. Endoprosthesis according to one of claims 1 to 10, characterized in that the endoprosthesis ( 10 ) is produced by a generative manufacturing process, or also called rapid prototyping. Endoprosthesis according to one of claims 1 to 10, characterized in that the endoprosthesis ( 10 ) is produced by a casting process. Endoprosthesis according to claim 12, characterized in that the casting process is a lost wax process. Use of an endoprosthesis with at least one channel ( 16 . 18 . 20 ) and / or at least one cavity ( 14 ) for endoscopy by passing over the at least one channel ( 16 . 18 . 20 ) or cavity ( 14 ) of the endoprosthesis ( 10 ) an endoscope ( 10 ) is introduced for the assessment of the healing process. Use of an endoprosthesis with at least one channel ( 16 . 18 . 20 ) and / or at least one cavity ( 14 ) for the drainage of wound water and blood at an implantation site and / or for the delivery of a medium which serves for the dissolution of bone cement or the regression of bone material at the implantation site in preparation for a revision surgery.

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