DE10134511A1 - Implantable condular big toe endoprosthesis system made up of a proximal implant and a distal implant has an anatomy-compatible geometry capable of being adapted to different particular requirements - Google Patents

Abstract

The implantable condular big toe endoprosthesis system made up of a proximal implant (1) with preferably three joint surfaces (2, 6), and a distal implant (13) with a separate plateau (18) or an integrated joint surface has an anatomy-compatible geometry capable of being adapted, via different variants, to different particular requirements.

Description

The present patent application relates to a big toe joint endoprosthesis system in the non-constrained design for therapy with different indications of the pathological big toe joints and takes into account the special anatomical Geometries of the four joint bones (Os metatarsale I, phalanx proximales hallucis, Ossa sesamoidea), which form the big toe joint, by the corresponding, indication-dependent versions. The modularity of the endoprosthesis system relates focus on the formation of the proximal and distal implants and the different ones Height of the plateau. The endoprosthesis system as a surface replacement with intramedullary Stems preferably assume the comprehensive preservation of the entire joint capsule and thus enables the clinical user via soft tissue management and Selection of different platform heights to adjust the belt tension, one Stabilization of the joint. By designing the endoprosthesis in the postoperative application of the joint to the patient all movements possible because no constrained guides restrict the range of motion.

The known statements on the prior art, mainly by purely technical Joint endoprostheses such as hinge joint prostheses with rigid or variable axes, Coupled or uncoupled ball joint prostheses with or without a simple, cylindrical one Implant stems, with or without sesame joint surfaces as concave, palmar cavities or one-piece silicone spacers are shown in detail different problem areas. The existing designs are relative small or missing stem surfaces marked towards the bone bed, which is therefore only have a low level of anti-rotation applications. Furthermore, the Anatomy-derived demands on the articular surface design of an endoprosthesis sometimes insufficiently considered.

Metal-metal sliding pairings are metal-UHMWPE sliding pairings or plastic-plastic sliding pairings have been realized.

An intraoperative implant adaptation for soft tissue management is largely the case the developments for technical reasons regarding the constructive design not intended.

• 1. Indikationsabhängige Auswahl des proximalen Implantates
• 2. Entwicklung einer anatomisch-technischen Endoprothese durch die Darstellung von anatomischen, konvex-konkaven Sesambeingelenkflächen am Implantat oder einer integrierten Sehnenführung als Sehnentunnel und die Schaffung von großen Implantatfixationsflächen im Knochenschaft.
• 3. Wahlmöglichkeit zwischen zementloser und zementierbarer Version
• 4. Möglichkeit des Rückzuges durch ein Folgeimplantat oder die Operation bzw. Implantation einer Arthrodese

The object of the present invention is to create a large toe joint endoprosthesis system with a versatile, universal concept which is optimized with special regard to the technical realizations, the safety aspects and the clinical application. These innovations relate to the current problems of the systems on the market and take the aforementioned aspects into account as follows:

• 1. Selection of the proximal implant depending on the indication
• 2. Development of an anatomical-technical endoprosthesis through the representation of anatomical, convex-concave sesame joint surfaces on the implant or an integrated tendon guide as a tendon tunnel and the creation of large implant fixation surfaces in the bone shaft.
• 3. Choice between cementless and cementable version
• 4. Possibility of withdrawal by means of a follow-up implant or the operation or implantation of an arthrodesis

The invention of an implantable big toe joint endoprosthesis system ( Fig. 1-- Fig. 48) consists of the different proximal and distal implants with a preferably separate plateau to the distal implant.

The endoprostheses are preferably for endoprosthetic care Designed to retain the joint capsule and the side ligaments.

The big toe joint endoprosthesis system can be non-constrained Design of the joint depending on the version as a ball joint type or as Rotational ellipsoid joint type are described and is basically as "low-friction System ", preferably based on a CoCrMo-PE sliding pair or ceramic Ceramic sliding pairing, with regard to the corresponding joint surfaces designed. Alternatively, the implants can also be manufactured from other approved ones Implant materials possible. The endoprosthesis elements preferably consist of a CoCrMo casting alloy and ultra-high molecular weight, cold-pressed polyethylene or ceramic coated CoCrMo forged alloy or other implantable Materials.

The design of the implant surfaces with respect to the bone tissue contact areas can vary with regard to the type of implantation and as a cementless or cementable variant be carried out. The implant stem surfaces are for cementless implantation including the adherent stabilizing wing with a porous, plasma process applied titanium coating or a HAK coating. alternative to The possible coatings can be the rear implant surfaces, the one Bone tissue contact should also maintain a macroporous, intercontaining space having implant surface, which consists of the metallic endoprosthesis material, exhibit. For implantation using bone cement, the corresponding are Implant stem surfaces including the adhering stabilization wing by a Sandblasting treatment very roughened.

The concave articular surface ( 2 ) of the proximal implant ( 1 ) has an anatomical-technical, mirror-symmetrical spherical articular surface ( 2 ) modeled on the circumference of the original joint head, which for technical reproducibility preferably has constant, identical or different articular surface radii in both planes ( 3 ) has been designed. Furthermore, there are two possible variants with integrated, convex-concave sesame joint surfaces ( 6 ) which can be designed both anatomically and thus asymmetrically or also technically and thus symmetrically. Alternatively, the proximal articular surface ( 2 ) can also have a palmar tendon tunnel ( 7 ), which represents a free space of the flexor tendon and, in the case of sesame bone removal, protects it against excessive pressure. The artificial, technical, spherical articular surface ( 2 ) preferably arises from a sphere that has a spherical segment removed on opposite sides and which has also been opened in the inner area in such a way that the metaphyseal bone bearing the joint cartilage does not have to be resected and the outer artificial joint surface circumference of the original, anatomical joint surface is adapted. Alternatively, as already described, the proximal articular surface ( 2 ) can also be mapped from a correspondingly reduced rotational ellipsoid instead of the ball. From the illustration of a joint surface, which reproduces the original, total joint surface circumference including the sesame joint surfaces ( 6 ) or a tendon tunnel ( 7 ), as shown in FIGS . 6-15, the number of necessary resections of preferably 3 or 4 sections results in the also represent the rear implant surfaces ( 10 ) in order to resect only the articular cartilage. In contrast to the design of the proximal implant with sesame bone gel surfaces ( 6 ) or a tendon tunnel ( 7 ) described above, the articular surface ( 2 ) of the proximal implant ( 1 ) can also only the proximal-distal part of the articular surface, as shown in FIGS. 21-30. map and thus preserve the anatomical sesame joint surfaces. This mapping of the articular surface ( 2 ) results in the reduced number of resections of preferably 2 or 3 sections, which also represent the rear implant surfaces ( 10 ), in order to resect only the proximal-distal articular cartilage.

The original, anatomical center of rotation ( 8 ) preferably corresponds to the geometric center of the proximal and distal articular surfaces ( 2 , 20 ), which is formed by the intersection of the flexion axis with the longitudinal axis of the implant. The implants ( 1 , 13 ) preferably have an axis offset ( 9 , 17 ) between the proximal center of rotation and the axes of the implant stems ( 11 ) for imaging or technical reproduction of the anatomical relationships.

In order to align the proximal joint body, formed from the artificial joint surface ( 2 ), with the anatomy of the original joint surface, the proximal implant ( 1 ) can also be designed in an anatomized design, and thus in a left and right version, as a result of the mirror-symmetrical design, thereby making the dorsal Articular surface termination ( 4 ) points laterally. Furthermore, the sesame bone joint surfaces ( 6 ) or the tendon tunnel ( 7 ) can also be realized in a mirror-symmetrical or anatomical and thus asymmetrical variant, which, like the mirror-symmetrical, dorsal joint surface closure ( 4 ), enables a reduction in the number of parts.

For the bony fixation of the artificial, previously described proximal joint body, formed from the artificial joint surface ( 2 ), it has a short, metaphyseal, anatomical-technical implant stem ( 11 ) in addition to the rear implant surfaces ( 10 ), which also represent the resection planes is preferably cylindrical or conical in shape and can also have an anatomical adaptation with regard to the cross-section of the stem. The final end of the implant stem ( 11 ) is preferably rounded. To enlarge the bony fixation surfaces or the implant surfaces located in the bone and to improve the rotational stability of the proximal implant ( 2 ), preferably tapered stabilizing wings ( 12 ) are attached to the implant stem ( 11 ). The number of stabilizing wings ( 12 ) can vary, but preferably amounts to 4 stabilizing wings ( 12 ), which, with regard to postoperative loads and the manufacturing process using wax injection molding technology and metal casting with their corresponding positioning, also perform the task of stabilizing the joint body against a possible geometric change in shape take.

The distal implants that complement the proximal implant ( 1 ) are a distal implant ( 13 ) with an integrated plateau receptacle ( 15 ) and a plateau ( 18 ), which is preferably designed as a PE plateau. Like the proximal implant ( 1 ), the distal implant ( 13 ) has an implant stem ( 11 ) with a stabilizing wing ( 12 ). The outer geometry of the plateau receptacle ( 15 ) as a metal back on the distal implant ( 13 ) is characterized in its outer contour by a circle with three surfaces, which are created by removing circular sections, around an anatomical-technical outer contour ( 14 ) of the plateau receptacle ( 15 ) with regard to the circumference of the implant in adaptation to the distal joint bone, to ensure maximum support on the resection surface and to prevent the plateau image ( 15 ) from protruding above the distal big toe joint bone, which can lead to irritation of the joint capsule and the ligaments , The rear implant surface ( 10 ) of the plateau receptacle ( 15 ), which also represents the resection plane or a bone contact surface, is preferably of simple design ( FIGS. 31-35), but can also, as shown in FIGS. 36-41, be multiple and thus be angled. The angled rear implant surface ( 10 ) has improved force transmission and additional rotational stability of the distal implant ( 13 ) in the bone shaft. In addition to the rear implant surface ( 10 ), a short, metaphyseal, anatomical-technical implant stem ( 11 ) is used for the osseous fixation of the distal implant ( 13 ), which is preferably cylindrical or conical in shape and can also have an anatomical adaptation with regard to the stem cross section. The end of the implant stem ( 11 ) is preferably rounded. To enlarge the bony fixation surfaces or the implant surfaces located in the bone and to improve the rotational stability of the distal implant ( 13 ), tapered stabilizing wings ( 12 ) are attached to the implant stem ( 11 ). The number of stabilizing wings is preferably 4, but can alternatively also vary.

The plateau receptacle ( 15 ) on the distal implant ( 13 ) is designed in different variants and allows different plateau types to be used. For a PE plateau with resilient locking, the plateau receptacle ( 15 ) is preferably circular and has a circumferential, inner bead as a locking application ( 16 ), behind which a corresponding, circumferential bead engages as a locking application on the PE plateau ( 19 ). As an alternative, the plateau receptacle ( 15 ) can also be designed as a cylindrical pot for accommodating a corresponding cylindrical pronounced plateau back, which is manufactured as a press fit or play fit. The cylindrical plateau holder with a clearance fit is suitable for accommodating a plateau ( 18 ) as a rotating plateau.

The plateau ( 18 ) is designed in different heights in order to adjust the ligament tension of the sidebands, which increases the distance between the proximal and distal metal implants ( 1 , 13 ), so that any resection deviations can also be compensated for intraoperatively.

The distal articular surface radius ( 21 ) in the plateau ( 18 ) is preferably slightly larger than the articular surface radius ( 3 ) on the proximal implant ( 1 ) in order to allow an eccentric position of the proximal and distal articular surfaces to relieve pressure at the implant interface and to reduce friction , Furthermore, the shape of the distal, concave joint surface ( 20 ) as a ball joint or an ellipsoid of rotation joint corresponds to the convex joint surface ( 2 ) on the proximal implant ( 1 ). In the case of ceramic-coated joint surfaces ( 2 , 20 ), the joint surface radii ( 3 , 21 ) are preferably almost identical for tribological reasons.

The details of the present great toe joint endoprosthesis system according to the previous description and the innovations formulated in the claims are shown in the accompanying drawings:

Fig. 1 Endoprosthesis in an overall view with convex joint surface, asymmetrical sesame joint surfaces and triple resection surfaces (bottom view)

Fig. Endoprosthesis 2 in full view with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection surfaces (rear view)

Fig. 3 endoprosthesis in full view with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection surfaces (front view)

Fig. 4 endoprosthesis in full view with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection (side view)

Fig. 5 endoprosthesis in full view with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection surfaces (top view)

Fig. 6 Proximal implant with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection surfaces (bottom view)

Fig. 7 Proximal implant with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection surfaces (rear view)

Fig. 8 Proximal implant with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection surfaces (front view)

Fig. 9 Proximal implant with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection (side view)

Fig. 10 Proximal implant with a convex joint surface, asymmetric sesamoid joint surfaces and 3 times resection surfaces (top view)

Fig. 11 Proximal implant with a convex joint surface, symmetrical sesamoid joint surfaces and 4 times Resektionsilächen (bottom view)

Fig. 12 Proximal implant with convex joint surface, symmetrical sesame joint surfaces and 4-fold resection surfaces (rear view)

Fig. 13 Proximal implant with convex joint surface, symmetrical sesame joint surfaces and 4-fold resection surfaces (front view)

Fig. 14 Proximal implant with a convex joint surface, symmetrical sesamoid joint surfaces and 4 times resection (side view)

Fig. 15 Proximal implant with a convex joint surface, symmetrical sesamoid joint surfaces and 4 times the resection surfaces (top view)

Fig. 16 Proximal implant with a convex joint surface, a convex-concave tendons tunnel and 4 times the resection surfaces (bottom view)

Fig. 17 Proximal implant with a convex joint surface, a convex-concave tendons tunnel and 4 times the resection surfaces (rear view)

Fig. 18 Proximal implant with convex articular surface, convex-concave tendon tunnel and 4-fold resection surfaces (front view)

Fig. 19 Proximal implant with convex articular surface, convex-concave tendon tunnel and 4-fold resection surfaces (side view)

Fig. 20 Proximal implant with convex articular surface, convex-concave tendon tunnel and 4-fold resection surfaces (top view)

Fig. 21 Proximal implant with convex articular surface, 2-fold resection surfaces (bottom view)

Fig. 22 Proximal implant with a convex articular surface, 2-fold resection surfaces (rear view)

Fig. 23 Proximal implant with a convex articular surface, 2-fold resection surfaces (front view)

Fig. 24 Proximal implant with a convex articular surface, 2-fold resection (side view)

Fig. 25 Proximal implant with convex joint surface, 2-fold resection surfaces (top view)

Fig. 26 Proximal implant with convex joint surface, 2-fold resection surfaces (bottom view)

Fig. 27 Proximal implant with convex joint surface, 2-fold resection surfaces (rear view)

Fig. 28 Proximal implant with a convex articular surface, 2-fold resection surfaces (front view)

Fig. 29 Proximal implant with convex joint surface, 2-fold resection surfaces (side view)

Fig. 30 Proximal implant with convex joint surface, 2-fold resection surfaces (top view)

Fig. 31 Distal implant with PE plateau locking application and simple resection surface (bottom view)

Fig. 32 Distal implant with PE plateau locking application and simple resection surface (rear view)

Fig. 33 Distal implant with PE plateau locking application and simple resection area (front view)

Fig. 34 Distal implant with PE plateau locking application and simple resection area (side view)

Fig. 35 Distal implant with PE plateau locking application and simple resection surface (top view)

Fig. 36 Distal implant with double resection surface without PE plateau locking application (bottom view)

Fig. 37 Distal implant with 2-fold resection surface without PE plateau locking application (rear view)

Fig. 38 Distal implant with double resection surface without PE plateau locking application (front view)

Fig. 39 Distal implant with double resection surface without PE plateau locking application (side view)

Fig. 40 Distal implant with double resection surface without PE plateau locking application (top view)

Fig. 41 Plateau with PE plateau locking application (bottom view)

Fig. 42 Plateau with PE plateau locking application (front view)

Fig. 43 Plateau with PE plateau locking application (front view in longitudinal section)

Fig. 44 Plateau with PE plateau locking application (top view)

Fig. 45 Plateau without PE plateau locking application for press fit or play fit adaptation (bottom view)

Fig. 46 Plateau without PE plateau locking application for press fit or play fit adaptation (front view)

Fig. 47 Plateau without PE plateau locking application for press-fit or play-fit adaptation (front view in longitudinal section)

Fig. 48 plateau without PE-plateau locking application for press-fit or clearance-fit adaptation (top view) List of designations for the representations of FIGS. 1 to 48 1 Proximal implant
2 Proximal, convex articular surface
3 Proximal, convex joint surface radius
4 Anatomical-technical lateral-dorsal joint surface termination
5 Anatomical-technical palmar joint surface closure
6 Medial and lateral anatomical-technical, convex-concave sesame joint surface
7 convex-concave tendon tunnel in the articular surface
8 Anatomical center of rotation
9 Proximal axis offset of the implant shaft axis to the center of rotation
10 Back anatomical-technical implant surfaces
11 Anatomical-technical implant handle
12 stabilizing wings
13 Distal implant
14 Anatomical-technical outer contour of the plateau mount
15 plateau view
16 Locking application for PE plateau in the plateau mount
17 Distal axis offset of the implant shaft axis to the articular surface rotation point
18 plateau, PE plateau
19 Locking application for PE plateau on the plateau
20 distal concave articular surface
21 Distal concave joint surface radius

Claims (20)

1. The implantable, condylar big toe joint endoprosthesis system as a joint surface replacement system with intramedullary stems is characterized in that the non-constrained endoprostheses, consisting of a proximal implant ( 1 ) with preferably three joint surfaces ( 2 , 6 ) for correspondence with the joint surface ( 20 ) on the distal implants ( 13 , 18 ) and the sesame legs or an articular surface ( 2 ) for correspondence with the articular surface ( 20 ) on the distal implants ( 13 , 18 ), a distal implant ( 13 ) with a separate plateau ( 18 ) or an integrated articular surface have an anatomical-technical geometry and allow intraoperative, indication-specific system adaptation through different variants of the implants. 2. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the proximal joint surface ( 2 ) is preferably provided with a constant, convex joint surface radius identical in both planes ( 3 ) and thus represents part of a ball or in one of the Another preferred embodiment is provided with two constant, convex joint surface radii ( 3 ) which are different in both planes and thus represents part of an ellipsoid of revolution. 3. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the proximal joint surface ( 2 ) in its palmar region two preferably asymmetrical, anatomically matched, convex-concave joint surfaces as sesame bone joint surfaces ( 6 ) or in a further preferred , technical design has two symmetrical sesame leg joint surfaces ( 6 ) which correspond to the sesame legs. 4. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the proximal joint surface ( 2 ) in its palmar region in a further preferred embodiment have a symmetrical or asymmetrical, anatomically adapted, convex-concave tendon tunnel ( 7 ) can, which serves as the tendon guide of the flexor tendon or tendon clearance in the case of sesame leg removal. 5. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the proximal joint surface ( 2 ) can be present as a sesame joint surfaces ( 6 ) without showing a palmar area with convex-concave joint surfaces. 6. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the dorsal joint surface closure ( 4 ) is preferably asymmetrical, extends laterally and is therefore adapted to the anatomy of the original, anatomical joint surface or in a further preferred embodiment one represents symmetrically designed joint surface termination ( 4 ). 7. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the anatomical center of rotation ( 8 ) is represented by the center of the proximal, convex joint surface ( 2 ). 8. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized in that by a proximal and distal axis offset ( 9 , 17 ) between the anatomical center of rotation ( 8 ) and the axes of the implant stems ( 11 ) an anatomical adaptation and corresponding geometry of the palmar overhanging, anatomical condyle is reproduced. 9. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the rear implant surfaces ( 10 ) on the proximal implant ( 1 ), which also represent the resection planes, depending on the indication, 2- / 3- / 4- or several times can be present. 10. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the proximal and distal implants ( 1 , 13 ) preferably a short, cylindrical implant stem ( 11 ) or an anatomically adapted, cross-sectionally oval or triangular implant stem ( 11 ) , which is preferably rounded at its end. 11. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the implant stems ( 11 ) are preferably provided with a plurality of conically tapering and thus anatomically adapted stabilizing wings ( 12 ), which bring about rotational stability and an increase in the intramedullary fixation surface. 12. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the anatomical-technical outer contour ( 14 ) of the plateau receptacle ( 15 ) on the distal implant ( 13 ) of the circumferential surface contour of the resection surface of the phalanx proximal hallucis by the preferred attachment of three surfaces on the otherwise circular geometry or by an oval design of the circumferential outer contour ( 14 ) is adapted. 13. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the distal, concave joint surface ( 20 ) in the PE plateau or plateau ( 18 ) is preferably provided with a constant, concave joint surface radius ( 21 ) or in one the further preferred embodiment is provided with two constant, concave articular surface radii ( 21 ) which are different in both planes and thus represents part of an ellipsoid of revolution. 14. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the PE plateau or plateau ( 18 ) is preferably rotationally symmetrical. 15. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the PE plateau or the plateau ( 18 ) is designed in different heights to adjust the ligament tension of the side ligaments to perform a joint stabilization. 16. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the distal plateau or PE plateau ( 18 ) with or without locking application ( 16 , 19 ) in the plateau receptacle ( 15 ) of the distal, metallic implant ( 13 ) can be fixed. 17. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the distal plateau ( 18 ) as a PE plateau with a locking application ( 19 ) in the plateau receptacle ( 15 ) with a corresponding locking application in the plateau receptacle ( 16 ) in the distal, implant ( 13 ) can be fixed. 18. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the rear implant surfaces ( 10 ) including the surfaces of the implant stems ( 11 ) with the stabilizing wings ( 12 ), which are to receive bone tissue contact, a cementless implantable, rough titanium coating or alternatively can have a HAK coating. 19. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the rear implant surfaces ( 10 ) including the surfaces of the implant stems ( 11 ) with the stabilizing wings ( 12 ), which are to receive bone tissue contact, one implantable with bone cement, by Sandblasting can have a roughened surface. 20. The implantable big toe joint endoprosthesis as a joint surface replacement is characterized according to claim 1, characterized in that the rear implant surfaces ( 10 ) including the surfaces of the implant stems ( 11 ) which are to contain a bone tissue contact, have a macroporous, intercontaining spaces having an implant surface made of the metallic endoprosthesis material can exist.