Title of Invention

ANGLE STABLE OSTEOSYNTHESIS PLATE WITH SPECIALLY DESIGNED NOTCH

Abstract The present invention relates to an osteosynthesis plate (lb) comprising at least two drilled holes (4, 4') arranged adjacent to one another. According to the invention, a notch (5b) is arranged on the convex side (6) of the osteosynthesis plate, between the at least two drilled holes arranged adjacent to one another.
Full Text FORM 2
THE PATENT ACT 1970 (39 of 1970)
&

The Patents Rules, 2003 COMPLETE SPECIFICATION
(See Section 10, and rule 13)
1. TITLE OF INVENTION : OSTEOSYNTHESIS PLATE

2. APPLICANT(S)
a) Name
b) Nationality
c) Address

SYNTHES GMBH SWISS Company EIMATTSTRASSE 3, CH-4436 OBERDORF, SWITZERLAND

3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed : -

VERIFICATION
I, Donald Joseph Edgar Mullen of 734 London Road, High Wycombe, Bucks HP11 IHQ, UK, herewith confirm that I am conversant with the German and English languages and am a competent translator thereof, and that to the best of my knowledge and belief the attached translation of International PCT Patent Application No. PCT/IB2004/001784 is a true and correct English translation of said Patent Application.
Declared at 734 London Road, High Wycombe, Bucks HPll IHQ UK




High Wycombe,
12 May, 2005 Donald J.E. Mullen

The present invention relates to an osteosynthesis plate according to the precharacterizing clause of Claim 1.
Osteosynthesis plates for implantation, anatomical reduction and internal splint fixation of bone fragments after fractures are known to a large extent in a very wide range of forms and developments. The success of fracture care is substantially determined by the stability of the implants. The stability is critical for ensuring healing of the fracture before failure of the implant. It should be as high as possible without the implant being excessively thick and hence too rigid. Excessive thickness of the implant could lead to a disturbance of the soft tissues. Furthermore, an implant which is comparatively stiff owing to an excessive thickness does not have the elasticity required for healing.
Osteosynthesis plates usually have a number of drilled holes through which bone screws for the fixation of the implants to the bone and hence for fixation of the fracture are passed. Particularly in the case of implants which are used in the articular region, frequently a plurality of drilled holes are arranged comparatively close together. Especially in the case of convex plates, this leads to a reduction of the stability in this region. The bearing cross-section is weakened there owing to the drilled holes. The region still remaining between the two drilled holes is firstly isolated and secondly is comparatively far away from the neutral fibres of the plate owing to the convex shape. Consequently, bending loads on the convex side result in an excessive stress, which could lead to failure of the plate precisely in this region. Thus, a comparatively small region is critical overall for the stability of an osteosynthesis plate. This may decide the success or failure of fracture care.
It is therefore an object of the present invention to improve the stability of osteosynthesis plates. In particular, it is intended to improve the stability of osteosynthesis plates where at least two drilled holes are comparatively close together.
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This and other objects are achieved, according to the invention, by an osteosynthesis plate according to Claim 1. Advantageous developments are to be found in the dependent Claims.
An osteosynthesis plate according to the invention has at least two drilled holes arranged adjacent to one another. According to the invention, at least one notch is arranged between these two drilled holes. As mentioned above, excessive stresses occur under bending loads on the convex side in the case of drilled holes arranged adjacent to one another. At first glance, it therefore does not appear very advantageous to remove even further material from a point of maximum load. Surprisingly, however, the opposite is the case. By means of the at least one notch, it is ensured that stress peaks are eliminated and the maximum bending load is distributed over a broader web. Furthermore, a part of the load is conducted to the outside of the plate. The region on the outside of the drilled holes is usually substantially broader than the web remaining between the drilled holes. Consequently, this can also take up a greater load. Such a relief notch is considered to be advantageous especially in an angle-stable plate osteosynthesis, since the total load is borne by the plate in the case of angle-stable anchoring.
The prior art already discloses plates which have incisions or notches at certain points. Thus, firstly, undercuts are known. In this connection, the osteosynthesis plate is provided with notches on the underside, with the result that the contact area between plate and bone is reduced. This results in less disturbance of the periosteal blood supply, which improves healing. Furthermore, lateral incisions in reconstruction plates are known, where they ensure better flexibility of the plate perpendicular to the longitudinal direction. Without these incisions, there is the risk that the plate would bend only across the material weakened by the drilled hole, resulting in a change in the shape of the drilled hole, which may be disadvantageous in the case of fixation by means of a bone screw. What is important, however, is that all these notches and incisions are in particular not made in the immediate region or the immediate environment of drilled holes. The cross-sections in the region of the
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drilled holes would be weakened by above-mentioned incisions. Moreover, the distortion of the drilled holes by the bending of the plate can be prevented only by a correspondingly greater distance of the incisions from the drilled holes. Consequently, the known osteosynthesis plates, whether with or without known incisions, cannot contribute to the achievement of the object. None of the known incisions and notches leads to a distribution or deflection of the load away from the critical region between the drilled holes.
The list of reference numerals and the drawing, together with the articles described or protected in the claims, are an integral part of the disclosure of this Application.
Description of figures
The invention can be even better understood by reference to the attached exemplary figures. They are described in relation to one another and overall. Identical reference numerals denote identical components, and indices indicate functionally identical components.
Fig. 1 shows a cut-out from a generic plate in side view (A), plan view (B) and perspective view (C); and
Fig. 2 shows an embodiment of an osteosynthesis plate in side view (A), plan view (B) and perspective view (C).
Fig. 1 shows a cut-out from a generic plate la in various views. The generic plate is a model for an osteosynthesis plate, in order to illustrate the basic principle of the invention. The cut-out, shown in Fig. 1, of the generic plate la has two drilled holes 2, 2'. The two drilled holes 2, 2' pass through the plate so that a screw can be introduced. A notch 5a is arranged between the drilled holes 2, 2’. As is evident from the drawing of Fig. IB, this notch 5a is present between the two drilled holes 2, 2’. In other words, the notch 5a links the two drilled holes 2, 2’; it runs from drilled hole 2
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to drilled hole 2’. The generic plate la is an arched plate. It has a convex side 6a and a concave side 7a. As is evident in particular from Fig. IC, the notch 5a is arranged in the convex side 6a. The concave side 7a remains unchanged.
Fig. 2 shows an osteosynthesis plate lb in various views. The osteosynthesis plate lb has different types of drilled holes. The term "drilled hole" is understood herein as meaning any orifice or bore in the plate according to the invention through which means for fixing the plate with and to a bone can be introduced. Thus, for example, both cylindrical and conical drilled holes as well as slots and drilled holes having a thread, and combinations thereof, are included therein. As is evident from Fig. 2, the two drilled holes 4, 4' in the middle region of the osteosynthesis plate lb are arranged comparatively close together. In the region of the two drilled holes 4,4', an excessive stress occurs under bending load on the convex side 6b, as mentioned above. According to the invention, a notch 5b extends between these drilled holes 4, 4'. By making the notch 5b, the load which rests on the web 12 in the region between the two drilled holes 4, 4’ is more uniformly distributed, for example deflected to the lateral webs 10, 10’, as indicated by the arrows 11. Particularly from the diagram of Fig. 2B, it is clear that the lateral webs 10, 10' are broader than the middle web 12. Consequently, the web 10, 10' can also take up a greater load than the web 12. Moreover, the area moment of inertia here is reduced only slightly by making the notch 5b, at the same time the extreme fibre spacing being disproportionately shortened. This makes a substantial contribution towards increasing the stability of the plate.
Fig. 2 shows that the proximal end 8, in contrast to the distal end 9, has a spoon-like shape, i.e. is arched. As a result, the osteosynthesis plate lb can be used both for the left and for the right proximal humerus. Owing to this arched, spoon-like design, however, it is precisely these bending loads as discussed above that occur. The relief notch is therefore extremely useful especially in the case of such osteosynthesis plates.
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The notch 5 is a recess which is introduced into the osteosynthesis plate. It can otherwise be described using the terms "incision" or "groove". The notch 5 is in particular rounded in order to reduce the influence of the notch effect.
The depth of the notch 5 depends on the curvature of the osteosynthesis plate 1. The greater this curvature, the deeper it is possible to form the notch. The side view of a plate may serve as an aid for determining the preferred depth of the notch 5. If, in side view, as shown in Fig. 2 A, the web 12 present between the drilled holes 4,41 no longer projects beyond the edge of the drilled holes, the notch 5 has the preferred depth. The curvature of the plate should conceal the notch in side view.
In other words, the notch 5 has a depth which substantially corresponds to the depth of the edge 15, 15’ and 17,17' of the drilled hole 4, 4' and 2, 2', respectively, which
depth is present in that region 19, 19' or 18, 18' of the drilled hole 4, 4' or 2, 2', respectively, which is transverse to the longitudinal axis of the notch 5 and which is further away from the notch. The notch is consequently preferably approximately as deep as the depth of the opposite edge of the drilled hole, which is clearly evident in particular from Fig. 1A and Fig. 2A. The "depth" of the edge of the drilled hole is understood thereby as meaning the distance between the edge of the drilled hole and the plane which lies on the top of the osteosynthesis plate. This definition also makes it clear that the depth is dependent on the curvature of the plate, the spacing of the drilled holes between which the notch is made and the thickness of the plate. However, the depth may vary. What is important, however, is that the notch is only so deep that no new exposed zone is produced, for example, on the outside of the drilled holes (in Fig. 2, in the region of reference numeral 10, 10’).
As mentioned above, the notch 5 is made between two drilled holes arranged adjacent to one another. In an embodiment, the notch 5 extends coaxially with a straight line 14 which connects the two midpoints 13, 13’ of the drilled holes 2, 2', as shown in Fig. IB. The longitudinal axis of the notch la consequently coincides with the straight line 14. In the case of special plate forms, in particular curved
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osteosynthesis plates, the notch 5 may be displaced from the middle of the web. Thus, it is intended that the relief notch be displaced parallel to this connection of the midpoints, as shown, for example, in Fig. 2B. Here, the notch 5b has been displaced in the direction towards the proximal end 8 of the osteosynthesis plate lb. The notch 5b forms the tangent to the two drilled holes 4, 4’. It is advantageous if the proximal region of the edge 16 of the notch 5 is approximately at the height at which the proximal region of the edge 15, 15’ of the drilled hole 4, 4' is present, or above this height. This ensures the load distribution.
As is evident in particular from Fig. 2, the notch 5 is arranged transversely to the longitudinal axis 3 of the osteosynthesis plate lb.
The drilled holes between which the notch is arranged are arranged adjacent to one another. Here, "adjacent" is understood as meaning that the drilled holes are comparatively close together. The exact magnitude of the distance between the adjacent drilled holes at which the present invention displays its advantageous effects depends in turn on the curvature of the osteosynthesis plate. Moreover, the size of the implant is decisive. Furthermore, it depends to a certain degree also on the total number of drilled holes arranged on the implant. In any case, two drilled holes are arranged adjacent to one another in the context of the invention if only a narrow web which leads to excess stresses at this point remains between them.
The two drilled holes 2, 2' or 4, 4' can also be regarded as being adjacent in the context of the invention if their spacing is not so great that the above-defined depth of the notch 5 exceeds the thickness of the osteosynthesis plate 1. This means that the distance between the drilled holes 2, 2' or 4, 4' arranged adjacent to one another depends on the depth of the notch 5 in that the notch is not deeper than the thickness of the osteosynthesis plate 1. If the depth of the notch 5 is therefore adapted to the depth of the opposite edge 15, 15' or 17, 17’ in the case of a curved osteosynthesis plate 1 at some time a point will be reached at which this edge 15, 15’ or 17, 17’ is present below a plane defined by the bottom of the plate, i.e. is lower than the
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bottom of the plate. If the notch 5 were then still to be as deep as the edge 15,15', 17, 17, this depth would be greater than the thickness of the plate and the latter consequently broken through. It is also clear there from that the spacing of the drilled holes in the case of more greatly curved plates will be smaller than in the case of plates having a smaller curvature. Here, the drilled holes between which the notch according to the invention is made may be further apart, and the notch can nevertheless perform its function according to the invention.
List of reference numerals
1 - Osteosynthesis plate
2 - Drilled hole
3 - Longitudinal axis
4 - Drilled hole
5 - Notch
6 - Convex side
7 - Concave side
8 - Proximal end
9 - Distal end
10- Lateral web
11 - Arrow
12- Web
13 - Midpoint
14 - Straight line 15- Edge
16 - Edge
17- Edge
18- Region
19- Region
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WE CLAIM:
1. Osteosynthesis plate (1) comprising at least two drilled holes (2, 4) arranged adjacent to one another, characterized in that at least one notch (5) is arranged on the convex side (6) of the osteosynthesis plate (1), between the at least two drilled holes arranged adjacent to one another.
2. Osteosynthesis plate according to Claim 1, characterized in that the notch (5) extends substantially coaxially with a straight line (14) which is formed by the midpoints (13) of the at least two drilled holes (2,4).
3. Osteosynthesis plate according to Claim 1, characterized in that the longitudinal axis of the notch (5) makes a tangent to the two drilled holes (2,4).
4. Osteosynthesis plate according to any of the preceding Claims, characterized in that the proximal region of the edge (16) of the notch (5) is present substantially at the height at which the proximal region of the edge (15) of the at least two drilled holes (2, 4) is present, between which the notch (5) is arranged, or above said height.
5. Osteosynthesis plate according to any of the preceding Claims, characterized in that the notch (5) is rounded.
6. Osteosynthesis plate according to any of the preceding Claims, characterized in that the notch (5) has a depth which substantially corresponds to the depth of the edge (15, 17) of the drilled hole which is present in that region (18, 19) of the drilled hole (2, 4) which is transverse to the longitudinal axis of the notch and which is further away from the notch.
7. Osteosynthesis plate according to Claim 6, characterized in that the spacing of the drilled holes (2,4) arranged adjacent to one another depends on the depth of
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the notch (5) in that the notch is not deeper than the thickness of the osteosynthesis plate (1).
8. Osteosynthesis plate according to any of the preceding Claims, characterized in that the notch (5) is arranged transversely to the longitudinal axis (3) of the osteosynthesis plate (1).
9. Osteosynthesis plate according to any of the preceding Claims, characterized in that the proximal part of the osteosynthesis plate is arched in a spoon-like manner so that the osteosynthesis plate can be used both for the left and for the right proximal humerus.
Dated this 15th day of November, 2006



HIRAL CHANDRAKANT JOSHI AGENT FOR
SYNTHES GMBH

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Abstract
The present invention relates to an osteosynthesis plate (lb) comprising at least two drilled holes (4, 4') arranged adjacent to one another. According to the invention, a notch (5b) is arranged on the convex side (6) of the osteosynthesis plate, between the at least two drilled holes arranged adjacent to one another.
(Fig. 2C)
To,
The Controller of Patents
The Patent Office
Mumbai.
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Documents:

1399-mumnp-2006-abstract(10-07-2008).doc

1399-mumnp-2006-abstract(10-07-2008).pdf

1399-mumnp-2006-abstract.doc

1399-mumnp-2006-abstract.pdf

1399-mumnp-2006-cancelled pages(10-07-2008).pdf

1399-MUMNP-2006-CLAIMS(29-8-2008).pdf

1399-mumnp-2006-claims(granted)-(10-07-2008).doc

1399-mumnp-2006-claims(granted)-(10-07-2008).pdf

1399-mumnp-2006-claims.doc

1399-mumnp-2006-claims.pdf

1399-mumnp-2006-correspondance-received.pdf

1399-mumnp-2006-correspondence(29-08-2008).pdf

1399-MUMNP-2006-CORRESPONDENCE(29-8-2008).pdf

1399-mumnp-2006-correspondence(ipo)-(02-12-2008).pdf

1399-mumnp-2006-description (complete).pdf

1399-mumnp-2006-drawing(10-07-2008).pdf

1399-mumnp-2006-form 1(10-07-2008).pdf

1399-mumnp-2006-form 18(10-07-2008).pdf

1399-mumnp-2006-form 18(20-11-2006).pdf

1399-mumnp-2006-form 2(granted)-(10-07-2008).doc

1399-mumnp-2006-form 2(granted)-(10-07-2008).pdf

1399-mumnp-2006-form 3(15-11-2006).pdf

1399-mumnp-2006-form 5(15-11-2006).pdf

1399-mumnp-2006-form-1.pdf

1399-mumnp-2006-form-18.pdf

1399-mumnp-2006-form-2.doc

1399-mumnp-2006-form-2.pdf

1399-mumnp-2006-form-26.pdf

1399-mumnp-2006-form-3.pdf

1399-mumnp-2006-form-5.pdf

1399-mumnp-2006-form-pct-ib-308.pdf

1399-mumnp-2006-form-pct-isa-210.pdf

1399-mumnp-2006-power of attorney(14-07-2006).pdf

abstract1.jpg


Patent Number 226533
Indian Patent Application Number 1399/MUMNP/2006
PG Journal Number 07/2009
Publication Date 13-Feb-2009
Grant Date 18-Dec-2008
Date of Filing 20-Nov-2006
Name of Patentee SYNTHES GMBH
Applicant Address EIMATTSTRASSE 3, CH-4436 OBERDORF,
Inventors:
# Inventor's Name Inventor's Address
1 SCHWER STEFAN TALWERG 44 79540 LORRACH
2 MARIETHOZ ERIC LES CLEVES CH-1997 HAUTE-NENDAZ
3 ANDERMATT DANIEL BAHNHOFSTRASSE 93B CH-4313 MOHLIN
4 MARTINELLI ORLANDO FELSENWEG 11, CH-4536 ATTISWIL,
PCT International Classification Number A61B 17/80
PCT International Application Number PCT/IB04/001784
PCT International Filing date 2004-06-01
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 PCT/IB2004/001784 2004-06-01 Samoa