DE102004042502A1 - Shoulder joint endoprothesis for human shoulders has an inlet side formed as a base in the structure of a rotation-symmetrical body - Google Patents

Abstract

Shoulder joint endoprothesis has an inlet side formed as a base in the structure of a rotation-symmetrical body. Preferred Features: The rotation-symmetrical axis of the base runs parallel to the inclination axis of the upper arm body.

Description

The The invention relates to a shoulder joint endoprosthesis for the artificial Joint replacement in humans. It is suggested that optional as a monoblock or preferably modular designed prosthesis with their load-bearing entrance side form as a base in the form of a body of revolution and with them its lateral surface in a corresponding congruent Ausschälung or cutout of anchor the upper end of the humerus. Accordingly, FIG the endoprosthesis according to the invention no shaft on. The anchoring of the input side can vary depending on execution each by cementing, screwing, press-fit clamping or Spreading done. For some of the proposed designs is the glenoid articulating outlet side of the endoprosthesis in her outer shape shaped as a so-called mushroom head and corresponds with this detail in principle the known embodiments. At the same time further developments are made available with the invention, which various adjustment or correction options with regard to mutual spatial Arrangement of input to output side, as well as combinability with modular parts. There are also versions in the form of so-called "inverse Shoulders "or so-called "slipper shoulders" proposed.

Of the Replacement of diseased or accidentally damaged joints has been part of it many years to daily Practice in accident surgery and orthopedics. In addition to artificial Hip and knee joints For some years, the replacement of damaged shoulder joints with Success applied.

The Requirements for artificial Joints arise from their load, which occurs as a variable load and over many years, as well as from the milieu influences, where the materials used are permanently exposed. In addition, these must Materials to be biocompatible to rejection reactions after implantation sure to rule out.

Specific Problems that are for the entire joint endoprosthetics result are the respective individual anatomical conditions, to the artificial Joint fits must become, around the existing in the healthy joint biomechanical and kinematic conditions in artificial At least approximate joint restore. At the shoulder joint are the conditions particularly complicated, because the shoulder joint an extraordinarily large range of motion However, the glenoid has only a very small part covered by the Gelenkkalotte.

ever according to the individual circumstances therefore different Types of artificial joints and these are made in different sizes, as possible to meet every application. There are also very different ones Philosophies about the construction of such implants, resulting in a large number different products.

Shoulder endoprosthesis according to the state of Technology is mostly modular and consists in the vast majority Number from an insertable into the humerus shaft whose proximal end with a conical pin for attaching a artificial Condyle is provided in the form of a flat mushroom head.

From the US 4,919,670 is z. B. a two-piece shoulder endoprosthesis according to the prior art. This consists of an insertable into the medullary canal of the humerus shaft, which has a slender cylindrical shape distally and dramatically thickened proximally. At the proximal end, it is bounded by an obliquely running surface from which a conical pin protrudes orthogonally. This conical pin is provided for the attachment of the mushroom-type artificial Gelenkkalotte with its inner conical blind hole. A two-piece shoulder endoprosthesis of this type is no longer adjustable after implantation in position relative to the natural glenoid.

For better adjustability, therefore, multipart systems have prevailed, in which an adjustable intermediate member is inserted between the shaft and the artificial calotte. The US 5,358,526 describes a shoulder endoprosthesis similar shape, in which between the shaft and artificial calotte, a coupling member is inserted. This can be connected either by means of a slide guide or via a conical connection of pin and bore with the shaft. On the artificial dome facing side there is a further conical connection of pin and corresponding bore. The three mentioned modular components are mutually rotated and / or adjustable and are secured against unintentional adjustment by mutually dipping cylinder pins. This and similar concepts therefore allow a fairly good adaptability to the individual anatomical situation.

Another type of shoulder endoprosthesis is described in WO 9410941. This concept could be called a slider shoulder. The special shoulder endoprosthesis consists of a concave humeral socket, which can be attached to the upper arm bone via an intermedullary prosthesis shaft, an artificial glenoid len joint socket, which is associated with the shoulder blade, and a joint ball, which is arranged freely movable between the humeral and glenoid joint socket. As with the endoprosthesis mentioned above, there is no possibility of individual adaptation or adjustment in this concept.

With the FR 2652498 the modular system of a shoulder endoprosthesis is presented, which allows the realization both in classical form as well as in the form of a so-called "inverse shoulder". Unfortunately, no possibilities of individual adjustment are offered in the cited document.

The proposed with the four references cited above and others Shoulder endoprostheses this Like style acceptable for certain medical indications be, z. B. at certain fractures of the upper arm, wherein the shaft take over the function of a bone nail should. On the other hand, this is an unphysiological stiffening of the upper arm, which its natural elasticity and compliance hinders or prevents. From the incongruity of the mechanical Parameters of the materials cooperating here bone / metal could be found in unfavorable make Loosening of the implant arise. Besides, with such chunky shanks a minimally invasive Surgical technique, as it is the goal today, hardly applicable.

The patent literature also discloses shoulder endoprostheses without a shaft. So will in the EP 1263351 a shaftless shoulder endoprosthesis described. This is a one-piece construction, which consists essentially of an artificial dome with firmly attached anchoring elements. As anchoring elements thin pins or narrow sheet metal tabs are to serve, which are intended for a pressfit fixation or a contribution with bone cement. A fundamental disadvantage of this concept is first the lack of any adjustment options. In addition, precise pre-processing of cancellous bone beneath the resection plane may be difficult and would require at least drilling or milling templates. A fixation by pressfit is unlikely to be presentable.

• • modulares System
• • physiologische Krafteinleitung in das obere Ende des Oberarmknochens
• • beliebige Fixierung (z. B. Zement, Pressfit, Spreizung, Einschraubung)
• • herstellbar als konventionelles Konzept, inverse Schulter, Gleitkörper-Schulter
• • weitestgehende Einstellbarkeit
• • minimal-invasive Operationstechnik
• • biokompatible Werkstoffe
• • geeignete Materialpaarungen
• • Langlebigkeit
• • verschiedene Größen

It was therefore the object to provide a shoulder endoprosthesis with the following properties and possibilities:

• • modular system
• • physiological application of force to the upper end of the humerus
• • Any fixing (eg cement, pressfit, spreading, screwing in)
• • can be produced as a conventional concept, inverse shoulder, slipper shoulder
• • as far as possible adjustability
• • minimally invasive surgical technique
• • biocompatible materials
• • suitable material pairings
• • longevity
• • different sizes

rationale the invention

The described object is according to the invention by a preferably modular system of a shoulder endoprosthesis solved, which focuses on a central Element in the form of a body of revolution builds - in the following called pedestal - and on a shaft entirely waived. A shaft is namely in many cases in a shoulder joint endoprosthesis at all not necessary and then brings only disadvantages.

Of the Socket according to the invention is assigned to the load input side of the prosthesis ensemble, ie implantation in the upper end of the humerus. He is at a cheap one Form shape readily accommodate in a gutted cavity there. This cavity can - similar to in acetabular cups - with appropriate Raffelfräsern easily also be created minimally invasive. The actual fixation can be done by means of bone cement, or by using the the hip endoprosthetics known Pressfit technique, also by spreading the base, and preferably via a screwing with a self-tapping thread of the base. According to the particular type of fixation, the respective socket in the following as a cementable base, as a pressfit socket, as a spreading socket or be referred to as a screw-in socket.

The proposed rotationally shaped Design of the base refers in principle to its lateral surface. It is understood that additional Elements such as slots, holes (eg for setting up a tool, to prevent rotation of the components), fins or screw-in sockets existing threads are not necessarily must be rotationally symmetric. The rotational shape of the base and its compact size allows allows a pronounced physiological transmission of power between the participants Partners and enough for the to be transferred personnel Completely out. It restricts also the elasticity of the humerus is not. In addition, it allows the realization both classic and inverse joint systems: it is also completely on a CNC lathe very much economical and save material to produce.

The contour of the rotational shape of the base according to the invention is in principle freely selectable. Theoretically, cylindrical, conical, spherical, parabolic, cylindrical-conical, cylindrical-spherical, conical-spherical or from various straight and / or curved lines existing or composite contours are applicable, provided that they are adapted to the anatomical conditions at the implantation in a favorable manner. According to the current state of research and development work, a conical-spherical contour of the shell of a shell at the pole and a tangent transition to the "equator" seems to fit best.

In In practice, it will be essential to have such sockets in different sizes Diameter jumps from Z. B. 1 or 2 millimeters to keep in stock. Here is the Span of the required area of the corresponding anatomical Sizes determined. The applicant estimates the demand maximum to a diameter of about 40 millimeters.

Of the Base of the shoulder endoprosthesis according to the invention is on his load-bearing exit side, ie towards the glenoid, according to the adjoining module designed. In the classical form, a pin can exist here be on which the artificial Gelenkkalotte is firmly plugged. This pin can be conical and / or - by one firm and torsion-proof fit of the artificial joint calotte too ensure - with one Profiling be formed. An adjustment possibility of the mutual lateral position is given when the corresponding hole the artificial one Joint calotte is arranged eccentrically. The desirable anti-twist device between the components, by the way, with any other suitable and methods known in the art are ensured, for. Via pins, corresponding holes, slots, lugs, screws and the like.

at a more refined shoulder endoprosthesis is between pedestal and artificial Gelenkkalotte a coupling piece inserted, so that Ensemble now over has three components. This coupling piece is firmly connected with the other two components mentioned - about conical and / or profiled cones, or by any other appropriate type of connection. It is proposed in this regard, the surgeon a whole set of different couplings available represent, whereby by varying the Lateralversatzes, the bending angle and / or the neck length the Geometry of the implant can be very finely adjusted to the optimum can. It goes without saying that too for this variant described a Verdrehsurchrung the components - such. B. previously described - required is.

The Invention is also implemented as a so-called bipolar design. This concludes to the base of a ball joint, which as a plain bearing for a special artificial Joint calotte serves. The artificial one Joint calotte accordingly has an inner concave calotte and at the same time an outer convex Dome, being the radius of the outer convex Dome noticeably larger than which is the inner concave calotte. To ensure the required Sliding properties between the components in sliding friction Here is the material pairing special attention to devote. Another aspect of this system concerns the mass of artificial Dome. It should be as small as possible be - about by combining a very thin one metallic wall with a core of lightweight plastic - with it the involved tendons, ligaments and muscles the artificial Hold the calotte in position to prevent unwanted tilting can.

The The bipolar system described above can also be used with the invention a reverse operation can be realized. For this, the joint ball must be rotatably supported in the interior of the base, z. B. by means of a Inlett acting as a plain bearing. She can then either with one fixed or optionally modular pin connected to the artificial dome become. The system allows a congruent positioning of the Rotary centers of joint ball and artificial Dome. However, the problems of the mass come here more strongly Wear as in the previously described concept.

A another mode of practicing the invention is in the form of a so-called slip-shoulder with an artificial one Glenoid replacement. Both glenoid replacement as well as the output side of the base each have concave Domes. In between is a slider in the form of a ball or inserted into a lens.

Finally will with the invention, the design of a so-called inverse shoulder offered. In this case, the base or one in the base used inlett as a concave storage area. The glenoid bearing becomes then converted to a ball joint using suitable components, which with the concave storage area of the pedestal articulated.

From the details of the invention explained above, the extreme bandwidth of the implementation possibilities already becomes clear. This also applies to the mentioned types of base. However, the design as a screw-in socket is likely to be particularly preferred. This is due to the fact that for a permanent fixation both a micro and a macrostructure of the base shell is required. The microstructure can be white without teres z. B. be generated by sandblasting or other techniques. The macrostructure is then present in the form of the thread. The microstructure facilitates the growth or integration of the bone, and the macrostructure prevents the base from wandering. In addition, arise in a proper execution of the thread during screwing no spreading forces, which would lead to an explosion of the bone stock in the humerus.

For an optimal Function of a screw-in socket is a sophisticated design of the Thread required. The screw-in socket should be a very small one Screw-in torque to screw easily to Aufsitzen to be. On the other hand, a high over torque and a possible large overturn angle required to overspecify sure to avoid. In addition, the optimal must Thread concept expressed in a high tactile mold to To reach the touchdown point as a tactile feedback to the surgeon convey. In doing so may in turn, completely different requirements during the intended use not except by the patient be left out. Indeed it depends, for the thread design a cheap Find a compromise that meets all these requirements.

For the practical execution the socket thread becomes a catchy one Pointed thread with slightly capped tip of the thread profile, one Tooth height of no more than 2 millimeters, a slope in the range of 5 millimeters, and proposed a Sockolpol inclined thread profile. Advantageous is also an adapted Gradient variation, a twisted shape of the flutes with positive Cutting edges, as well as restricted Thread teeth.

In the execution the socket as screw-in socket are still connection options for the Instrumentarium - by name for one Key - required. For this purpose, corresponding mating surfaces are suitable, for. B. in shape a crown gearing at the equatorial Edge, or slots, grooves, holes, polygonal pins or holes, or others for suitable solutions for this purpose.

meeting the drawing figures

The Invention and the developments according to the invention should for better understanding will be explained in more detail below with reference to the 16 drawing figures. All Drawing figures were each shown as a sectional image. It demonstrate:

01 : The truncated shoulder joint side of the natural human upper arm.

02 : A two-piece shoulder joint endoprosthesis according to the invention with conical screw base and eccentric offset.

03 : The cut AB off 01 of the natural human humeral head.

04 : The positioning of the two-piece shoulder joint endoprosthesis 02 on average AB in the completely cancellous bone area.

05 : A two-part shoulder joint endoprosthesis according to the invention with enlarged screw-in socket and partial cortical anchoring in section AB.

06 : A shoulder joint endoprosthesis according to 05 with excessive ruffling of the bony bearing.

07 : A two-piece shoulder joint endoprosthesis according to the invention with a conical-spherical screw-in socket.

08 : A shoulder joint endoprosthesis as in 07 , but with cylindrical-spherical screw-in socket.

09 : A shoulder joint endoprosthesis as in 07 , but with spherical screw-in socket.

10 : A shoulder joint endoprosthesis as in 07 , but with parabolic screw-in base.

11 : A shoulder joint endoprosthesis as in 07 , but with a rotational fixing of cylindrical pin and holes.

12 : A shoulder joint endoprosthesis as in 07 , but with a rotational fixation of a male and female conical serration.

13 : A shoulder joint endoprosthesis as in 07 , but with a bilateral conical plug-in coupling with radial offset.

14 : A shoulder joint endoprosthesis as in 07 , but with a bilateral conical plug-in coupling, each with male and female serrations with axial angular misalignment.

15 A shoulder joint endoprosthesis according to the invention with a movable spherical bearing of the mushroom head.

16 : A shoulder joint endoprosthesis according to the invention with a movable spherical La clutch in the screw-in base.

The 01 shows in a somewhat idealized way of representation the sectional view of a cut shoulder joint side of a human upper arm 1 , The medial bone tubular bone has a slightly off-center medullary cavity 4 on, so that the cortical wall 3 thinner in the body direction than the cortical wall facing away from the body 2 , It is a centerline related to the outer contour of the humerus 5 drawn dash-dotted. Towards the shoulder joint, the corresponding wall thicknesses thin out, with a hump-like thickening in the area of the greater tubercle 9 is formed. A second cusp, called Tuberculum minus, can not be seen in the drawing figure because of the chosen presentation. The humeral head (caput humeri) usually has in the upper area 7 a slightly lower cortical wall thickness than in the lower area 6 and is limited by a well-defined edge (Collum anatomicum), in which here a bold dashed line is the resection plane 8th for the following drawing figures 3 . 4 . 5 and 6 should clarify. Another line drawn in bold dash-dotted lines is the drawing sectional plane AB, which was placed in the middle axis of the humeral head. The filling of the humeral head with. cancellous bone 10 was schematically represented by means of a Fleckrasterung.

02 shows in an also cut drawn representation of the upper arm 01 after resection of the humeral head and implantation of an embodiment of a two-piece shoulder joint endoprosthesis according to the invention. The reference numbers 1 to 5 , such as 9 and 10 were therefore retained. The one component of the shoulder joint endoprosthesis consists of a conical screw-in socket 12 with thread, of which a single tooth is representative by the reference numeral 13 is characterized as well as a conical pin 14 , The screw-in socket 12 is in the example shown in cancellous bone 10 screwed. The other component is a Gelenkkalotte 15 , which with its inner cone firmly on the conical pin 14 of the screw-in socket 12 is plugged. The axis of rotation of the Gelenkkalotte coincides with the bold dash-dotted drawn cutting plane AB, which for the still following drawing 3 to 6 was used. It is offset from the axis of rotation of the screw base in the plane of the drawing by the amount X. The center of rotation (center of an imaginary ball matching the ball portion of the joint calotte) is indicated in the drawing by the reference numeral 11 Mistake. In practice, it will be necessary to adjust the exact position of the joint cup according to the anatomical conditions of the patient.

In 03 is a sectional view of the upper arm in the plane AB from the 01 shown in the condition before surgery. The closed cortical mantle has different sized parts 16 . 18 and the natural calotte 17 educated. In the cutting plane, the cortical coat is complete with cancellous bone 10 filled. The point of intersection 19 The thin dash-dotted axis marks the center of rotation of the anatomical system.

In the 2 shown situation after implantation is in 4 shown as a view of the cutting plane AB. The screw-in socket 12 is with the teeth 20 . 21 . 22 . 23 . 24 . 25 and 26 of its thread over its entire surface in the cancellous area 10 anchored to the humerus. The rotation axis 27 the screw-in base is just like the axis of rotation 28 the artificial dome 15 drawn as a thin dash-dotted line. Both components are offset in the drawing plane by the amount Y of about 1 mm from each other. The artificial dome with its inner cone is fixed on the outer cone 14 the screwed body inserted. The center of rotation of the artificial system is indicated by the reference numeral 11 characterized.

One opposite the 4 slightly modified situation is in 5 shown. The cutting plane is the same as before and on the side of the bone with the cortical wall 16 and the cancellous area 10 represents. The screw-in socket 29 now has a slightly larger diameter, reducing its thread teeth 30 . 31 . 32 . 33 . 34 . 35 and 36 partially anchored in the cortical wall. The rotation axis 37 the screw-in base is opposite the axis of rotation 28 the dome 15 and the center of rotation 11 of the artificial system in the plane of the drawing in turn offset by the amount Y of about mm. Both components are above the conical pin 38 the screw-in socket and the inner cone of the artificial dome. The drawing is intended to demonstrate that even a partial or total cortical anchoring of the implant according to the invention is possible.

The range of operational freedoms is based on the 6 be demonstrated. In a largely with the 5 matching representation and correspondingly adopted reference numerals, the application of an exaggerated Vorraffelung is shown here, which z. B. in artificial conical acetabular cups prior art. Between the ground 39 the vorgeraffelten cavity and the front side of the screw base is formed as a gap of about 1 mm depth. This distance is to guarantee even in the case of misalignment between the conical implant and the gerugrelten cavity a full-scale conical area.

7 shows a geometric modification of the screw-in socket. Since the complete installation situation is not absolutely necessary for understanding, the bone embedding has been omitted. The screw-in body 40 is now conical-spherical. The frontal ball section 50 joins with a clean tangential transition to the conical area 49 at. Of the circumferential thread are eight teeth 41 . 42 . 43 . 44 . 45 . 46 . 47 and 48 to be seen in the sectional view. Both the conical pin 52 , as well as the artificial calotte 15 are identical in their dimensions and their positioning with the embodiments shown above. The rotation axis of the screw-in base was identified by the code number 51 marked. A conical-spherical design of the screw-in base according to the one shown here seems to represent a solution for a shoulder implant adapted particularly well to the anatomical conditions.

Another modification of the Einschraubkörpers is in 8th shown. The body of the screw-in socket 53 has now been designed cylindrical-spherical. The enlarged in its diameter frontal spherical area 63 goes towards the "equator" in a relatively short cylindrical area 62 above. The thread is based on the eight teeth 54 . 55 . 56 . 57 . 58 . 59 . 60 and 61 clarified. The conical neck of the screw-in socket was indicated in the drawing by the reference numeral 65 , and its axis of rotation with 64 marked. The execution of the thread shown here and in the other drawing figures in terms of the number of flights, the pitch, the tooth profile, the number of revolutions, etc., however, are only to be understood as exemplary and do not necessarily mean a corresponding determination or recommendation. Rather, the invention can be practiced in this regard in a wide range of practical applications.

As the 9 shows, the shoulder implant according to the invention is also with a purely spherical shell shape 73 the screw-in socket can be shaped. The spherical screw-in socket 66 It is quite flat, so that only a smaller number of thread turns can be realized with an unchanged thread pitch. The corresponding thread is made by means of the teeth 67 . 68 . 69 . 70 . 71 and 72 represents. For the conical neck of the screw-in socket became the code number 75 and for its axis of rotation the code number 74 forgive.

As a final example of the variety of possible shell shapes 10 serve. Here was for the screw-in socket 76 a parabolic shell shape 85 selected. There are eight thread teeth in the sectional view 77 . 78 . 79 . 80 . 81 . 82 . 83 and 84 located. The conical pin received the code number 87 , the rotation axis of the screw-in socket the code number 86 , The artificial dome 15 and its axis of rotation 28 with the distance Y were taken over unchanged from the preceding drawing figures.

11 shows details of a further embodiment of the invention with reference to a screw-in socket 88 , which is equipped with a rotation lock. For the example, a screw-in base with a conical-spherical shell shape was selected, which should best correspond to the anatomical conditions in the humeral head. The sectional view is eight teeth 89 . 90 . 91 . 92 . 93 . 94 . 95 and 96 to see the thread. The screw-in base is provided with a number of blind holes, of which only two 97 . 98 can be seen in the sectional view. The artificial dome 101 is equipped with at least one corresponding blind hole, with an inserted cylinder pin 104 relative rotational movements between screw-in socket and dome around the pin 100 around stops. In the figure are still both the axis of rotation 99 of the screw-in base, as well as the axis of rotation 102 the artificial dome, the axis distance Y and further the center of rotation 103 of the artificial system.

In 12 is shown another type of anti-rotation. The pin 115 of the screw-in socket 105 is designed as a conical multiple toothing, which with a corresponding conical internal toothing of the artificial calotte 116 corresponds. In this case, this type of connection takes over the clamping fixation by means of an adapted conical angle, as well as the desired rotational security between the two components. The finer the toothing, the smaller the adjustable angular steps and thus the resolution of the eccentric positioning. Incidentally, there are still the eccentric offset Y between the axis of rotation 117 the artificial calotte and the axis of rotation 114 of the screw-in socket, the teeth 106 to 113 of the thread, and the center of rotation 118 of the system.

Out 13 It can be seen that the modularity of the shoulder system according to the invention even further expanded and thus the adaptability to the anatomical requirements can be further increased. The drawing shows an embodiment with a turn conical-spherical screw 119 with thread and the teeth visible in section in the drawing 120 to 127 , Between the artificial dome 133 and the screw-in socket is a coupling piece with mutual cone 130 . 131 inserted, which is firmly inserted to one side in a conical bore of the screw-in socket and on the other side firmly into a conical bore of the artificial calotte. The coupling piece has a collar in the example shown 132 , which without stop in a grö Outer cylindrical countersinking 129 of the screw socket dips. This collar can z. B. serve the preparation of a tool for the purpose of extraction. In the drawing figure are still the rotation axis 128 of the screw-in base, the axis of rotation 134 artificial dome, the center of rotation 135 of the system, and the eccentric offset Y is recorded between both axes of rotation.

Based on 14 a further development of the invention will be presented. This concerns an angular adjustability of the components. Externally, the screw-in socket shown differs 136 in his mantle shape and his thread with his teeth 137 to 144 not the embodiment shown above. He is by means of a coupling piece 147 . 148 . 149 with the artificial dome 150 connected. The coupling piece is, starting from a central collar 149 , equipped on both sides with a conical multiple toothing, the lower side 147 is firmly inserted into a corresponding toothing of the screw-in socket, and the upper side 148 firmly in a corresponding toothing of the artificial calotte. In order to avoid the attack of the federal government of the coupling piece is the screw-in base with a cylindrical recess 146 vesehen. The artificial calotte also has a recess 153 on to stop the striking at the "equator" of the screw base. In the drawing is still the axis of rotation 151 the artificial calotte and the axis of rotation 145 of the screw base. Since both ends of the coupling piece are pivoted against each other at an angle α, the artificial dome is adjustable by appropriately repositioning the compound in its orientation. With a number of different coupling pieces with different angles and optionally additional Lateralversprüngen so all conceivable orientations are adjustable.

15 shows a development of the invention in the form of a modular four-part prosthesis. The screw-in socket 154 was in his outer contour and with his teeth 155 to 162 his thread for the sake of simplicity taken from the preceding drawing figure. The recess 164 on its "equatorial" side was enlarged and the conical pin 165 pulled down to the newly formed plane surface. On the conical pin is a ball joint 170 firmly attached with its inner cone. It is in an inner sphere section of an inlay 168 rotatably mounted. The center of the joint ball, which simultaneously forms the pivot point of the inlets, is indicated by the reference numeral 171 specified. The artificial dome housing 166 is quite thin-skinned and takes with its inner contour, which consists of a spherical section and a cylindrical section, the inlett form-fitting manner. In the illustrated embodiment, there is a return between the dome housing and the inlet 169 , which is to allow a greater angle of movement of these two components relative to the screw-in socket before the plane surface of the insert comes to the stop at the edge of the screw-in base. The drawing figure also has the axis of rotation 163 of the screw base, as well as the center 167 of the ball portion formed by the Kalottenmantel. In practice, for. For example, in this embodiment, the screw base may be made of titanium or a titanium alloy, the ball joint of ceramic, the insert of polyethylene, and the dome housing of so-called surgical steel (a chromium-cobalt-molybdenum alloy). In principle, such material pairings from the field of artificial hip joints are known and acceptable for the present application.

Finally, by means of 16 another embodiment of the invention will be presented. Again, for reasons of lower drawing effort, the outer contour of the screw-in socket 172 with his thread teeth 173 to 180 accepted. However, the screw-in base now has a shell-like shape with a thin wall and an inner cylindrical-spherical contour. In this inner cavity is an inlay 181 positively pressed. In the example shown, the inlay is designed with a constant wall thickness. On its inside there is a hemispherical bearing surface, which is a bearing head 183 rotatably receives with its ball portion. The other side of the bearing head is as a conical pin 182 educated. On this conical pin is the artificial joint calotte 185 with its corresponding inner cone 184 firmly attached. In the artificial joint calotte is a circumferential recess 187 incorporated so that a sufficient pivoting angle of the artificial system is ensured. Because of this recess, the artificial joint cap in the region of its "equator" is merely in the form of a shell 186 existent. The drawing also shows the axis of rotation 188 of the bearing head and the common pivot point 189 to remove the moving components.

The Range of embodiments provided with the invention embodiments is enormous and would a big Number of drawing figures require, if every single detail should be shown here. To illustrate the invention Underlying principles are likely the above explained However, figures familiar to the person skilled in the art readily be enough.

Claims (2)

Shoulder joint endoprosthesis with one each on a load to be transmitted input and output side, wherein the input side of the proximal end of the upper arm and the output side facing the scapula, and the input side to the proximal end of the humerus is firmly connected and the output side in the implanted state with the glenoid region of the Shoulder blade is directly or indirectly in a movable connection, characterized in that the input side is formed as a base in the form of a rotationally symmetrical body. Shoulder joint endoprosthesis according to claim 1, characterized in that that the Rotation axis of the base substantially parallel to the inclination axis of the humeral head.