Abstract:
In the case of a U-shaped surgical clip having two arms that are connected to one another via a deformable web, in order to stabilise the inherently deformable web in the non-deformed state it is proposed that the web bears, at least in some sections, a parallel web which is fixed on either side of the web and which restricts the deformability of the web in the reinforcing section of the web in which the parallel web and web are disposed next to one another.

Description:
The present invention relates to the subject matter disclosed in German patent application 198 58 581.0 of Dec. 18, 1998, the entire specification of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     The invention relates to a U-shaped surgical clip having two arms that are connected to one another via a deformable web. 
     With such surgical clips the application is performed by compressing the two arms, whereby the vessel to be clamped is disposed between the arms. The web connecting the two arms has to be deformed at the same time, i.e. it is distorted, and in so doing it is desirable to require the smallest possible deformation forces for the distortion of the web during the application operation. On the other hand, the web however has to have a certain stability in the non-deformed state of the clip, since it has to be ensured that the clip remains in the open state, for example upon insertion into an application magazine. In such magazines the clips are guided by laying the outer side of the arms against guide faces, and it is therefore important that the spacing of the arms is maintained; the web is responsible for ensuring this spacing and it therefore has to apply a certain strength. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to construct a generic surgical clip so that it firstly has sufficient stability in the web region at least in the non-deformed state, but upon deformation offers slight resistance in this region. 
     This object is achieved in accordance with the invention with a surgical clip of the type described at the beginning in that the web at least in some sections bears a parallel web that is fixed to either side of the web, and which restricts the deformability of the web in the reinforcing section of the web in which the parallel web and web are disposed next to one another. 
     Such a reinforcement of the web, which occurs at least in some sections, results in that the non-deformed web can keep the arms spaced from one another in the desired manner, secondly upon the deformation of the web, possibly with the simultaneous deformation of the parallel web, it is possible to reduce this strength, since curved webs can offer slight resistance to such a deformation by virtue of the geometric changes. 
     It is particularly advantageous if the strength of the parallel web is less than that of the web, so that the parallel web breaks upon the deformation of the web and consequently the reinforcement in the reinforcement section is removed. 
     It may be particularly specified that the reinforcing section is the central section of the web. 
     In a preferred embodiment it is specified that the web is bulged in a curve in the reinforcing section and the parallel web is disposed on the inner side of the bulge. 
     In particular with such an arrangement it is favorable if the parallel web bears projections which upon the bending aside of the web in the reinforcing section lie against the web and as a result maintain the bulge. As a result the bulged web is prevented from being deformed upon the distortion of the web with the formation of impermissibly small curvatures, which could result in damage. 
     In particular, the projections may be thickened portions in the parallel web, between which a weakened predetermined breaking point of the parallel web is situated. Thus it is possible that, even after the breaking of the parallel web, the thickened portions still guarantee the bulging of the web in the reinforcing section. 
     The parallel web can join the web with both ends, in a modified embodiment it may also be specified that the parallel web extends between two projections of the web, for example when the web bears catch projections which, when the clip is applied, engage in catch recesses of the arms. In another embodiment it is specified that the parallel web extends between a projection of the web on the one hand and the web itself on the other hand. 
     It is advantageous if the web is constructed as a flexible strip, at least in the reinforcing section, so that an integral hinge connection is constructed. 
     In a preferred embodiment it is also specified that, via the junction point of the arms with the web, the arms comprise rearwardly projecting extensions which bear catch means, which upon the compression of the arms fix the extensions to one another. As a result it is ensured that the deformed clip remains in the compressed position even when the web itself has not got a sufficiently stable construction to absorb the entire clamping forces of the clip. 
     At the same time it is advantageous if the catch means fixing the extensions to one another are disposed at the rear end of the extensions. 
     Furthermore, it may be specified that at the front end of the clip the arms bear catch means, which fix the arms to one another upon the compression of the arms. These catch means also hold the two arms together in the applied state, these catch means can be provided either alone or in combination with the catch means on the rear end of the arms. 
     The clip is preferably made from plastics material, in particular from a reabsorbable plastics material. 
     It is favorable if both arms are outwardly curved and the convex sides are faced towards one another, and as a result the central regions of the applied clip exert uniform compressive forces on the clamped container. 
     This effect is further enhanced if the arms have a smaller cross section in the central region than in the front region and than in the rear region. 
     The following description of preferred embodiments of the invention serves for further explanation in conjunction with the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a perspective view of a surgical clip in the non-deformed state; 
     FIG. 2 shows a top view of the surgical clip of FIG. 1 in the non-deformed state (unbroken lines) and in the deformed state (dash-dot lines); 
     FIG. 3 shows a view similar to FIG. 2 of another preferred exemplified embodiment of a surgical clip; 
     FIG. 4 shows a view similar to FIG. 2 of another preferred exemplified embodiment of a surgical clip and 
     FIG. 5 shows a view similar to FIG. 1 of a clip represented in a simplified manner with catch means for connecting the two arms at the rear end. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The clip  1  represented in FIGS. 1 and 2 comprises two arms  2 ,  3  that extend substantially parallel to one another and have a substantially rectilinear construction with a slight outward curvature, so that the convex inner sides of these arms  2  and  3  are faced towards one another. 
     In the central region both arms  2 ,  3  comprise a cross section which is reduced in relation to the front and the rear end, and in this central region both arms  2 ,  3  are connected to one another via a strip-shaped flexible web  4 . 
     The inner sides of the two arms  2 ,  3  form clamping jaws  5 ,  6  between the front end and the junction of the web  4 , which may be contoured in a suitable manner known per se, and the portion of the arms  2 ,  3  between the rear end and the junction of the webs  4  forms an extension  7 ,  8  in each case. 
     The web  4  bears on its outer side, spaced from one another and symmetrically to its centre, two ledge-shaped projections  9 ,  10 , which strengthen the web  4  over its length and in this manner define three hinge-joint regions, namely a hinge-joint region  11  at the junction of the web  4  into the arm  2 , a hinge-joint region  12  at the junction of the web  4  into the arm  3  and a central hinge-joint region  13  between the two projections  9  and  10 . 
     The two projections  9  and  10  are connected to one another via a parallel web  14 , which extends parallel to the central hinge joint region  13  spaced from the web  4  and which stabilises the web  4  in the central hinge-joint region  13 , so that the two projections  9  and  10  and the portions of the web  4  associated therewith enclose a fixed angle with one another, for example an angle of roughly 90°, when the clip is not deformed. The strength of the parallel web  14  is chosen so that upon the bending together of the web by the deformation of the central hinge-joint region  13 , the parallel web  14  breaks open and thus easily permits a deformation of the central hinge-joint region  13 . 
     Situated in the two extensions  7  and  8  are longitudinal grooves  15 ,  16  that are open to the inside and which are disposed and dimensioned so that, upon the compression of the two arms  2  and  3  and the resultant folding together of the sections of the web  4 , the projections  9  and  10  dip into the longitudinal grooves  15  and  16 . In this inserted position the projections  9  and  10  are retained in the longitudinal grooves  15  and  16  are either frictionally by clamping or by positive locking, in the represented exemplified embodiment the projections  9  and  10  comprise lateral catch projections  17 , which engage behind corresponding catch projections  18  in the longitudinal groves  15 ,  16 . The catch projections  17  and  18  are elastically deformable, so that upon the entry of the projections  9  and  10  into the longitudinal grooves  15  and  16  they yield and enable the entry, but the projections  9  and  10  are prevented from moving out of the longitudinal grooves  15  and  16  by the catch projections  17  and  18 . 
     The clip represented in FIGS. 1 and 2 is made from plastics material, in particular from a reabsorbable plastics material, and is preferably constructed as a single-part component. 
     To apply this clip, said clip is for example displaced in a magazine by the arms  2  and  3  abutting guides with their outer sides. This position is stabilised by the central hinge-joint region  13  of the web  4  being firstly strengthened by the parallel web  14 , so that a reinforcing section  29  is produced, as a result of which a perfect guidance in the magazine is guaranteed without the danger of jamming. 
     For the application itself, the arms  2  and  3  of the opened clip  1  are moved up to a vessel (e.g., blood vessel) to be clamped, and then the two arms  2  and  3  are guided towards one another by a suitable tool, so that the clamping jaws  5  and  6  clamp the vessel enclosed between them in the desired manner. 
     In so doing the parallel web  14  breaks open, the web  4  is deformed until the web sections lie against the inner side of the extensions  7  and  8 , and in this position the web is stabilised by the dipping of the projections  9  and  10  into the longitudinal grooves  15  and  16 , i.e. in the rear part of the clip it is no longer possible to distance the arms  2  and  3  from one another. 
     Projections  19 ,  20  that are directed towards one another and that are constructed as catch projections are represented in the front region in the exemplified embodiment of FIGS. 1 and 2, so that when the arms  2  and  3  are brought closer to one another they are also locked with one another in the front region, with the result that there too it is no longer possible to distance the arms  2  and  3  from one another. 
     Represented in FIG. 3 is a clip which corresponds to that of FIGS. 1 and 2 to a large extent, and parts that correspond with one another therefore bear the same reference numbers. 
     In contrast to the clip in FIGS. 1 and 2, here the parallel web  14  is not disposed between projections  9  and  10 , but the web  4  itself forms in the central hinge-joint region  13  between adjacent projections  9  and  10  a portion  30  that is outwardly bulged in a curve, while on the inner side of this outwardly bulged portion  30  the parallel web  14  merges into the web  4 . The parallel web  14  comprises two thickened portions  31 ,  32  over its longitudinal extension, which project towards the bulged portion  30  of the web  4  and which between them enclose a weakened predetermined breaking point  33 . 
     In the case of the non-deformed clip (FIG. 3 in unbroken lines) the portion  30  of the web  4  is strengthened by the parallel web  14  with the formation of a reinforcing section  29 , however upon the compression of the arms  2  and  3  the parallel web  14  breaks open in the region of the predetermined breaking point  33  and with the thickened portions  31  and  32  is applied from the inside against the portion  30  that bulges in a curve. As a result the web is slightly deformable in the central hinge-joint region  13 , the thickened portions  31  and  32  guarantee that the portion that bulges in a curve  30  retains its bulge and is not extended with the formation of regions of very small curvature and thus is not possibly damaged. 
     Represented in FIG. 4 is a modified exemplified embodiment of a clip, which has a very similar design to the clip in FIG. 1, and identical parts therefore bear the same reference numbers. 
     In contrast to the clip in FIGS. 1 and 2, projections  9  and  10  in this exemplified embodiment are not placed directly on the outside of the web  4 , but these projections  9  and  10  are integrally formed on a lateral lug  21 , which in the centre of the web  4  protrudes from said web. All remaining regions of the web  4  are constructed as flexible strip material, however these regions are stabilised with the formation of a reinforcing section  29  by parallel webs  22  and  23 , which connect the projections  9  and  10  each with a part of the web  4  that is remotely situated. Here too the parallel webs  22  and  23  have a weaker construction than the web  4  itself, so that upon the compression of the clip the parallel webs  22  and  23  break open and enable a free deformation of the web  4 . 
     As in the exemplified embodiment of FIGS. 1 and 2, the projections  9  and  10  dip into the longitudinal grooves  15  and  16  when the clip is compressed. 
     Finally, the clip represented in FIG. 5 is restricted in its representation to the two arms  2  and  3  and the web  4 , however it is obvious that with this clip too the remaining configurations of the exemplified embodiments described can be used. 
     In addition to the catch means already described, in this exemplified embodiment interacting catch projections  24  and catch recesses  25  are also provided at the rear end of the arms  2  and  3 , i.e. at the rear end of the extensions  7  and  8 , and when the clip is compressed said projections and recesses directly fix the arms  2  and  3  to one another also at the rear end. Such a locking combined with the locking of the web  4  with the extensions  7  and  8  and combined with the locking of the projections  19  and  20  produces a clip which in the applied state clamps an enclosed container in a permanent and strong manner without there being the danger of this clip unintentionally opening. 
     In this case the retaining forces are not produced by bending resistance of the web  4 , so that the web  4  itself can have a flexible and easily deformable construction, with the result that the application of the clip  1  is facilitated.