The invention concerns a device which is used in culturing at least a component of a biological joint replacement, and specifically, activates its differentiation into a joint replacement which is capable of bearing weight; in that a fulling point, that is, a maximum pressure range—or in the case of hinge joints, a fulling line—repeatedly progresses largely over the entire joint replacement surface by a moving fulling bowl, whereby the fulling bowl at least possesses a shape which comes close to that of the joint replacement surface, and flushes joint replacement production substances into the fulling gap which is produced in this manner.
The worldwide number of arthroses (“joint wear”) is increasing. Sooner or later, they can only be corrected with a joint replacement. Current metal endoprostheses with gliding surfaces made from metal, ceramics or plastics only have a limited service life and weight bearing capability, aside from other problems.
At the present time, however, only minor cartilage defects can be replaced by inserting cartilage components which were taken from other locations or cultured. Arthroplastic abrasion is limited to arthroses which are not very advanced, and can only delay the problem to some degree. Culturing (tissue engineering) of tissues has made major advances. However, it was not possible thus far to produce a perfectly hyaline joint replacement which is capable of bearing weight, and therefore implantable.
The present invention concerns the problem of solving issues of common mechanical endoprostheses and limitations of current cartilage replacement methods by manufacturing an implantable biological joint replacement.
This problem is solved by the devices with the attributes of claim 1. The sub-claims list various technical embodiments and joint replacement production substances 6a of the fulling device.
In order to produce a joint replacement with hyaline cartilage which can bear full weight, the process according to the invention is that in addition to the devices known in tissue engineering processes, it possesses a fulling device which provides the prerequisites for the growth and generation(=differentiation) of a joint replacement, particularly a cartilage layer which is capable of bearing weight, but also the carrying layer (preferably consisting of bone) and possibly also a connective layer. Herein a fulling process (fulling motion) is performed by the fulling device, at least mainly across the entire surface of the joint replacement being formed, by a fulling point or fulling line which moves over this surface. Also an additional gliding motion of the fulling bowl (or the joint replacement surface which is positioned on a fulling bowl) may be provided against the other joint replacement surface. Together with flushing at least one joint replacement production substance into the fulling gap by means of a flushing device—and the diffusion of these substances into the tissues, which is activated by the fulling process—this activates a specific tissue differentiation of the joint replacement or its parts, i.e. the formation of a biological joint replacement with the required weight bearing capacity.
The fulling device for producing a weight bearing biological joint replacement by means of a specific fulling point/fulling line motion which is performed by fulling bowls whose shape and curvature at least nearly corresponds to the joint replacement surfaces as described in the patent claims is not known, and research showed no indicators of similar patent applications.
Regarding cultivation procedures of tissues for materials which are suitable for joints, there are e.g. the following applications:
The following applications
also show compression of the tissues being cultured, usually also with varying pressure loads, and US 2002/106625 A1 also with only partial pressure loads on the surfaces. WO 2010/005917 A2 also specifies rollers which roll over the tissue being produced in a flat plane, i.e. they are not usable for a shaped joint replacement.
These rollers fundamentally differ from the fulling bowls of the invention and do not have the specific effects of the fulling device according to the invention, since the curvature of the roller deviates far from that of the tissue surface, and thereby the pressure acts on a relatively small surface and results in strong lateral compression shifting of the adjacent tissues with its cells, which—without destroying them—only allows a pressure load which is not sufficient to activate the tissues into a weight bearing differentiation, also partly because the joint replacement production substances between the roller and the joint surface are mainly shifted by the roller, and not strongly activated to diffuse into the tissues; which, however, does occur in the fulling process according to the invention. None of these patent applications features a fulling device which corresponds to that of the invention.
Further benefits result from the sub-claims and the following description.
The invention is described in further detail in the following, using exemplary embodiments which are shown in the included figures.
The Principle of the Fulling Device is Shown in Combination with
In some of the known processes, for instance, pressure is applied on cartilage with alternating pressure forces to produce the cartilage; however, this is done either by exposing its surface to consistent pressure, or by a pressure stamp exercising the same pressure on the surface, or by rolling a roller over the cartilage.
This, however, does not have the fulling effect according to the invention, since e.g. the roller applies pressure force on the cartilage which, due to the strongly differing curvature of the roller—e.g. as compared to the cartilage surface—squeezes the tissues which are being produced apart(=pressure force is crosswise to the pressure direction, meaning the tissues are squeezed to the sides), since this lateral pressure force is not met by nearly equally high pressure from the surrounding tissues and would therefore tear them if the pressure which were applied to them were sufficiently high to activate differentiation; that is, the cell walls and the tissue framework are exposed to excessive traction force if pressure which, in principle, is activated to differentiation by a roller crosswise in relation to its pressure force.
Due to these differences as compared to the device according to the invention, these pressure application processes in the thus far known devices for producing joint replacements or cartilage replacements are the reason why the differentiation of the cartilage tissues into a weight bearing joint replacement does not occur; that is, the processes which are thus far available could not be used to produce a biological joint replacement.
During the development of a joint, it is exposed to a pressure motion which is similar to that of the fulling device according to the invention.
In the invention, only a small fulling gap 4i is provided for differentiation fulling, with the specification, however, that there is not only joint lubricant in this narrow fulling gap 4i to produce the joint replacement 3a (as in the joint itself), but also at least one joint replacement production substance 6a, e.g. cells and/or tissue framework particles can also be flushed in. This is performed by a flushing device 6 (which is therefore provided in the inventive fulling device) through which the joint replacement production substance 6a is flushed into the fulling gap 4i from its edge or through inflow openings 10a, channels, holes, pass-through openings or porosity in at least one of the fulling bowls 4. For sealing to the outside, the fulling gap 4i can be provided with a fulling gap foil 4k, a fulling gap sealing bar 4l, a fulling gap foil pouch 4m, or a fulling gap sealing tube 4r.
The process of the fulling device in the production of the joint replacement 3e has a starting and end point, whereby the fulling device is used at least in the end area.
End area signifies that e.g. a cartilage layer 1 was cultured with one of the thus far available procedures, and the fulling device is then used to activate the differentiation into weight bearing cartilage 1(=differentiation fulling). Starting area means that even the beginning of the cartilage cultivation takes place under the influence of the fulling device, i.e. in the fulling device. In the course of this, fulling initially takes place without fulling pressure 4e(=pressure application), but only with a fulling depth 4f, i.e. a reduction of the gap between the fulling bowls 4, whereby the joint replacement tissues are cultured in this gap(=tissue culturing chamber 5=fulling gap 4i) by introducing cells 6c, tissue particles/framework particles/framework substance 6d. This can also be implemented by first producing a thin tissue layer whose thickness/strength then constantly increases, whereby the fulling depth 4f is adjusted to this increase by being reduced, and the fulling pressure 4e rises from practically zero at the outset to the end value.
This simultaneously shapes and differentiates the joint replacement 3e by the accordingly shaped fulling bowls 4, which may also be replaced by increasingly larger fulling bowls. In the course of this, e.g. cartilage or cartilage particles are placed in a shaping fulling device (see
In order to continue building the joint replacement 3e in the fulling device after commencing cultivation, the fulling gap 4i can reach a low width/gap at a certain distance from the fulling point 4c or the fulling line 4d, into which tissue particles (framework particles) 6d and cells 6e are flushed, or while the fulling bowl 4 is repeatedly lifted slightly away from the joint replacement surface during the fulling process (particularly if the fulling point 4c is located in the marginal areas of the joint which is being produced), and the fulling gap 4i thereby reaches a width/distance which is provided for the required process of flushing in the tissue particles (framework particles) 6d and cells 6e.
Overall, the joint replacement 3a can therefore be produced in one work step with the fulling device according to the invention, or it can take place in several processes as follows:
Furthermore, a gliding motion drive 4g is provided as needed; this causes a gliding motion of the joint bowls 4b or of a joint replacement 3e which is positioned on a fulling bowl 4 against the surface of the other joint replacement 3e.
In addition to the substances thus far used for cell cultivation, it is also possible to use e.g. joint lubricants 6e (or also substances which contribute to its development, such as synovial fluids, glucosamine, chondroitin, hyaluronic acid or collagen). These were not used in tissue engineering of joint replacements thus far. Even in the event that the fulling device according to the invention does not provide an additional gliding motion, a fulling process can result in a gliding motion—however minimal—particularly at the maximum distance to the fulling point 4c/the fulling line 4d. The use of joint lubricants (also with substances which are dissolved or dispersed in them) can also have favorable effects due to the compression at the fulling point 4c, particularly into the cartilage layer, and furthermore activate the differentiation, particularly of the cartilage layer, into hyaline, weight bearing cartilage. Aside from known differentiation and tissue engineering substances 6b, specific substances 6g can also be considered in this regard (e.g. methylsulfonylmethanes(=MSM), anti-interleukin-1 (IL 1-Ra)), which can have this effect when pressed into cartilage, bone and/or connective layers.
Differentiation substances 6f which activate tissue differentiation particularly in combination with fulling are also provided. Furthermore, connection substances 6h, which encourage the activation of a connection between two layers of the joint replacement 3e under the influence of the fulling motion and/or generate a connective layer on the side of the bearing layer 2, which is later applied to the bony joint head/joint pan, are also provided.
The following provides an overview and definition of the control devices 8 and motion devices 11, which generate the fulling motion with the fulling perform device 7 (that is, a fulling motion device 7a and a fulling intensity device 7b), and which are shown as examples in the following diagrams:
The control device 8 is combined with the fulling perform device 7 and controls at least the fulling intensity device 7b and/or the fulling motion device 7a and/or the flushing device 6, namely e.g. by means of electronic control devices, e.g. programmable and/or processor guided control devices, approximately corresponding to those in CNC devices, and it possesses at least one of the following setting devices for this purpose: mechanical, hydraulic, hydropneumatic, pneumatic or electrical setting devices.
The motion devices 11 are based on at least one of the following systems/devices:
In order to achieve an additional gliding motion either between one fulling bowl 4 and the joint replacement 3e or between the joint replacement parts 3e which are mounted on the fulling bowls, a rotation can additionally take place by means of a gliding motion drive 4g of the fulling bowl carrier 4h of the base bowl 4a as shown, for example, in these diagrams, while this possesses e.g. the function of a pivoting motion device 11b and/or a rotation motion device 11c. This gliding motion could also be obtained by mounting the motion devices 11, 11a-11o on a housing which is then rotated.
From the flushing device 6, the joint replacement production substances 6a flow through infeed lines 10 and via inflow openings 10a—directly or indirectly into the fulling gap 4i—and flow back into the flushing device 6 via return flow openings 10c and return flow lines 10b. The fulling bowls 4 and joint replacements 3e correspond to those in the preceding diagrams. In
The fulling gap 4i may also be at least partly sealed to improve the flushing process, as well as a part of the housing and the fulling process against its other part. The seals, which at least partly seal the fulling gap 4i and/or do so in at least one flow direction, consist of at least one of the following devices: a foil/membrane 4s, a flexible fulling gap sealing bar 4l, a fulling gap sealing tube 4r, an elastic connection/fulling gap edge foil 4k, a fulling gap foil pouch 4m, which fills out the fulling gap 4i, whereby parts of the fulling device, including the fulling gap edge seals 4j, consists of at least one of the following materials:
metal, foamed metal, hard and/or soft and/or elastic and/or compressible plastic, including polyactide, foam, foam rubber, ceramics, including tricalcium phosphate or tricalcium phosphate crystals, whereby at least one of the materials possesses at least one of the following attributes: permeable or impermeable to at least one of the joint replacement production substances 6a, firm, flexible, elastic, compressible, fluid absorbing, i.e. porous or spongious or perforated, and filled at least with one of the joint replacement production substances 6a-6h, with a gas and/or liquid.
For this process, it can also be provided that the fulling bowl 4 (here joint bowl 4b) is repeatedly completely lifted off the joint replacement 3e at time intervals by the fulling perform device 7, so that the thus expanded fulling gap 4i fills with joint replacement production substances 6a. In all of these processes, the joint replacement production substances 6a are distributed throughout the fulling gap 4i by the fulling motion, and compressed against the joint replacement 3e, i.e. they are massively activated to diffuse into the joint replacement 3e. The pressure difference between the infeed 10 and the return flow line 10b causes the joint replacement 3e to be supplied. If the fulling bowl 4 is permeable, a foil/membrane 4s may also be mounted as shown on the right-hand edge of the joint bowl 4b, separating one part of the housing and the fulling device from the other part.
Both fulling bowls 4 are base bowls 4a, i.e. fulling bowls on which the carrying layer 2 or the part of the joint replacement 3e opposing the joint gliding surface is mounted, i.e. one of the base bowls 4a bears a joint pan surface replacement 3a, and the other bears the opposing joint replacement 3d, in this case the joint head surface replacement. In this example, both joint replacements consist of three layers, i.e. the cartilage layer 1, carrying layer 2 and connective layer 3. The joint gap 4i is minimized in the entire area here, i.e. the fulling gap width consists only of a thin layer of a substance which also possesses joint lubricant attributes.
The joint pan surface replacement 3a, via the fulling bowl 4 of which the fulling pressure of the pressure transmission gliding surface 11t is applied, possesses a smaller spherical bowl section than the opposing joint head surface replacement 3d.
For this reason, the fulling bowl 4, 4a in the sectional plane of the diagram is connected with a traction connector 25 by two, although actually three or four pivoting levers 24; the traction connector is also moved by motion devices 11 and controlled by a control device 8—namely in such a manner that the joint pan surface replacement 3a moves across the entire opposing joint head surface replacement 3d, whereby this motion is coordinated with the motions of the fulling motion devices 7a by the control device 8.
As in the previous diagrams, rotation of the joint head basebowl 4a and its fulling bowl carrier 4h by a gliding motion drive 4g with motion devices 11b, c is also possible here. If this embodiment is used as a fulling device for a hinge joint, i.e. it is a sectional depiction crosswise to the axis line of the hinge joint, one of the semicircular tracks 18b is omitted, as well as the pivoting motion/rotation by the gliding motion drive 4g.
Here, the base bowl 4a may be additionally (see below) pivoted or rotated by means of gliding motions (via a gliding motion drive 4g) in order to encourage the even distribution of the tissue particles 6d or cells 6c. In this manner, it is possible to introduce tissue particles 6d and cells 6c continuously or in stages, which are gently pressed against the already existing tissue layer by the fulling motion, and are activated to connect with the tissue layer.
The firmer the cartilage tissue becomes, the more the fulling pressure 4e is increased by the control device 8, whereby the fulling depth 4f is pulled back insofar as necessary.
In this example, a second infeed line 10 is provided from the flushing device 6 with joint replacement production substances 6b, 6f-6g (but without tissue particles 6d and cells 6c), which are introduced into the hollow space 4q of the base bowl 4a. The base bowl 4a is permeable to these substances 6b, 6f-6g, whereby e.g. the nutrient supply to the joint replacements is improved. Likewise, the joint bowl 4b is permeable here to these joint replacement production substances 6b, 6f-6g (but not for tissue particles 6d and cells 6c). (Alternatively, the joint bowl 4b could be impermeable, then the infeed line 10 into the hollow space 4q of the base bowl 4a would perform the function of a return flow line 10b).
In this example, the fulling bowl holder with channel 12 contains a closing rod 12b. This can also be used to control the inflow of the joint replacement production substances 6a-6h. In particular, however, when no further supply of cells 6c and tissue particles 6d is required, it can be advanced so far that the previous opening in the fulling bowls 4, 4b is closed, and the spherical surface shape of the fulling bowl 4, 4b also exists in this area.
The device complexes 30, 31 and 32 can contain the fulling perform device 7 with its components 7a, 7b, a control device 8, and—as needed—a pressure system 9 for pressure motion devices 11 or pressure-independent motion devices 11, and e.g. into the vertical direction, a force transmission device 11n with a force transmission rod 11o. This force transmission rod 11o, which proceeds in a vertical direction, moves a bearing fork 19, in which the device complex 31 with the motion devices 11, 11a, 11o, 11f-11m, 7b (e.g. also with a fulling intensity device function) is embedded, and which moves the fulling bowl motion device with channel 12a around its pivot axis as well as into its axial direction in a gliding bearing 18g. In the horizontal direction, and via a bearing fork 19, a device complex 32 with motion devices 11, 11a, 11o, 11f-11m is pivoted; it moves the device complex 33 with the motion devices 11, 11a-11c, 11f-11m, 7b via a force transmission rod 11o and a bearing fork 19. As a fulling intensity device 7b, this moves the fulling bowl holder with channel 12 via an axial motion, and can also perform its fulling motion by means of pivoting and/or rotation.
Overall, this results in the fulling process as described above.
In this example, the fulling gap is sealed by a fulling gap sealing tube 4r. If this embodiment is used as a fulling device for a hinge joint, i.e. it is a sectional depiction crosswise to the axis line of the hinge joint, at least one of the bearing forks, e.g. bearing fork 19, is omitted, as well as the gliding motion drive 4g.
These devices are mounted on the pivoting arm 26 of a pivoting shaft 27, whose axis line 11r progresses through the sphere center of the base bowl 4a, i.e. the joint center point 18 of the joint replacement 3e. The axis lines of the fulling intensity device 7b, 11a-11c and the axis of the gliding motion drive 4g, 11b-11c also progress through the axis intersection point 11s. The axis 11r of the pivoting shaft 27 and the fulling intensity device 7b are perpendicular to each other. The pivoting drive of the pivoting shaft 27 and the axis 11q of the fulling bowl carrier 4h are moved by the fulling perform device 7 with the fulling motion devices 7a, here the pivoting motion devices 11b, whereby these motions are coordinated by the control device 8. These fulling devices are also suitable for a hinge joint, i.e. they can be seen as a sectional depiction crosswise to the axis line of the hinge joint. A pivoting motion/rotation by the gliding motion drive 4g, 11b-11c and the pivoting/rotation motion devices in 7b, 11a-11c is then excluded.
In
The forward drive rod 11p is positioned on bearings on the carrier rail 28 for this purpose. The motion of the forward drive rod 11p is controlled by the fulling perform device 7—in this case, a fulling motion device 7a—which moves the forward drive rod 11p by means of a linear motion device 11a. In this manner, the fulling point moves nearly across the entire surface of the fulling bowl 4, 4b.
The control of the motion device 11a, 11n, which applies the fulling pressure 4e to the force transmission rod 11o, and the linear motion device 11a on the carrier rail 28 is performed by the control device 8 via the control lines 8a. In this example, an opening is provided on the peak of the joint bowl 4b with an infeed 10 for joint replacement production substances 6a, which are flushed into the fulling gap 4i and the fulling gap mat 4n which is located there. The fulling gap 4i is sealed by a fulling gap sealing tube 4r.
In another embodiment, the bowl, which was thus far a fulling bowl 4, 4b, can also consist of a linear guided pressure body 23, which applies its pressure via a pressure transmission gliding surface 11t on the fulling bowl 4a (which is the joint replacement 3e in the above description) as a fulling motion.
The pressure foils 9e which lie on the fulling bowl 4, 4b or the joint replacement 3e which is being formed are porous in this example, so that the pressure system 9 also has the function of the flushing device 6 with the joint replacement production substances 6a.
Number | Date | Country | Kind |
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10 2011 100 073.2 | Apr 2011 | DE | national |
10 2011 103 457.2 | Jun 2011 | DE | national |
Number | Date | Country | |
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Parent | PCT/DE2012/000415 | Apr 2012 | US |
Child | 14066051 | US |