Device for the cerclage of fractured bones and system for the cerclage of fractured bones comprising such device

Abstract

A device for the cerclage of fractured bone as well as to a cerclage system using such device are provided. The cerclage device comprises a cerclage wire or thread and at least one spacer arranged on the cerclage wire or thread. The at least one spacer is made as a band having a substantially rectangular plan and a concave profile. Owing to the concave profile, the band can adapt to the surface of the fractured bone; in addition, the force exerted on the bone by the cerclage wire is advantageously distributed over the entire surface of the band. The cerclage device further comprises at least one safety thread which allows preventing the spacer from becoming lost in the patient's body in case the cerclage wire or thread tears off.

Claims

1. A cerclage device for the cerclage of a fractured bone, comprising a cerclage wire or thread, which is arranged for being tightened and fastened around the fractured bone, and at least one spacer, which is arranged on the cerclage wire or thread for maintaining the cerclage wire or thread at a certain distance from the fractured bone, wherein the at least one spacer is made as a band having a substantially rectangular plan and a concave profile, wherein the band has a pair of end walls, which are bent so as to extend in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone, and wherein each of the end walls is provided with a through-hole for the passage of the cerclage wire or thread, whereby the cerclage wire or thread is guided parallel to a longitudinal axis of the band, wherein the cerclage device further comprises at least one safety thread, wherein a single stop element is arranged on the safety thread, wherein each of the end walls of the band is correspondingly provided with at least one additional through-hole, wherein the safety thread passes through the respective additional through-holes of the end walls of the band and is guided parallel to the longitudinal axis of the band, whereby at least one of the end walls of the band is farther from an end of the safety thread than the stop element, and wherein the stop element has a size larger than the size of the additional through-holes of the end walls of the band.

2. The cerclage device according to claim 1, wherein the stop element is arranged at one end of the safety thread.

3. The cerclage device according to claim 1, wherein the stop element is arranged between the end walls of the band.

4. The cerclage device according to claim 1, wherein the face of the band that, in use, is intended to be in contact with the surface of the fractured bone has a smooth surface.

5. The cerclage device according to claim 1, wherein the face of the band that, in use, is intended to be in contact with the surface of the fractured bone is provided with projecting teeth.

6. The cerclage device according to claim 1, wherein the band comprises, in addition to the end walls, one or more intermediate walls, which extend in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone, each of the intermediate walls being provided with a through-hole for the passage of the cerclage wire or thread and with at least one additional through-hole for the passage of the at least one safety thread.

7. The cerclage device according to claim 1, wherein the band comprises a pair of bent tabs, which are arranged on the opposite lateral sides of the body of the band and extend in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone.

8. The cerclage device according to claim 1, wherein the band is preformed so as to have a desired concave profile.

9. The cerclage device according to claim 1, wherein the band is made of a deformable material and is adaptable to the profile of the fractured bone to which the cerclage device is applied.

10. The cerclage device according to claim 1, wherein the through-holes of the end walls of the band for the passage of the cerclage wire or thread are closed through-holes and have a circular profile.

11. The cerclage device according to claim 1, wherein one or more through-holes of the end walls of the band for the passage of the cerclage wire or thread are through-holes that are open toward a direction facing away from the face of the band that, in use, is intended to be in contact with the surface of the fractured bone.

12. The cerclage device according to claim 6, wherein the through-holes of the intermediate walls of the band for the passage of the cerclage wire or thread are closed through-holes and have a circular profile.

13. The cerclage device according to claim 6, wherein one or more of the through-holes of the intermediate walls of the band for the passage of the cerclage wire or thread are through-holes that are open toward a direction facing away from the face of the band that, in use, is intended to be in contact with the surface of the fractured bone.

14. A cerclage system for the cerclage of a fractured bone, which comprises an osteosynthesis plate and one or more cerclage devices according to claim 1.

15. A cerclage device for the cerclage of a fractured bone, comprising a cerclage wire or thread, which is arranged for being tightened and fastened around the fractured bone, and at least one spacer, which is arranged on the cerclage wire or thread for maintaining the cerclage wire or thread at a certain distance from the fractured bone, wherein the at least one spacer is made as a band having a substantially rectangular plan and a concave profile, wherein the band has a pair of end walls, which are bent so as to extend in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone, and wherein each of the end walls is provided with a through-hole for the passage of the cerclage wire or thread, whereby the cerclage wire or thread is guided parallel to a longitudinal axis of the band, wherein the cerclage device further comprises at least one safety thread, wherein a stop element is arranged on the safety thread, wherein each of the end walls of the band is correspondingly provided with at least one additional through-hole, wherein the safety thread passes through the respective additional through-holes of the end walls of the band and is guided parallel to the longitudinal axis of the band, whereby at least one of the end walls of the band is farther from an end of the safety thread than the stop element, wherein the stop element has a size larger than the size of the additional through-holes of the end walls of the band, and wherein the stop element is arranged between the end walls of the band.

16. The cerclage device according to claim 15, wherein the face of the band that, in use, is intended to be in contact with the surface of the fractured bone has a smooth surface or is provided with projecting teeth.

17. The cerclage device according to claim 15, wherein the band comprises, in addition to the end walls, one or more intermediate walls, which extend in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone, each of the intermediate walls being provided with a through-hole for the passage of the cerclage wire or thread and with at least one additional through-hole for the passage of the at least one safety thread.

18. The cerclage device according to claim 15, wherein the band comprises a pair of bent tabs, which are arranged on opposite lateral sides of the body of the band and extend in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone.

19. The cerclage device according to claim 15, wherein the band is preformed so as to have a desired concave profile.

20. The cerclage device according to claim 15, wherein the band is made of a deformable material and is adaptable to the profile of the fractured bone to which the cerclage device is applied.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Additional features and advantages of the invention will be evident to the person skilled in the art starting from the ensuing detailed description of some preferred embodiments of the invention, provided by way of non-limiting example, with reference to the attached drawings, in which:

(2) FIGS. 1A and 1B illustrate cerclage systems of known type for fractured bones;

(3) FIG. 2 shows a cerclage device for fractured bones according to a first embodiment of the invention;

(4) FIG. 3 shows a cerclage device for fractured bones according to a first variant of the first embodiment of the invention;

(5) FIG. 4 schematically shows the cerclage of FIG. 3 applied to a fractured bone;

(6) FIG. 5 shows a cerclage device for fractured bones according to a second variant of the first embodiment of the invention;

(7) FIG. 6 shows a cerclage device for fractured bones according to a second embodiment of the invention;

(8) FIG. 7 shows a cerclage device for fractured hones according to a first variant of the second embodiment of the invention;

(9) FIG. 8 shows a cerclage device for fractured bones according to a second variant of the second embodiment of the invention;

(10) FIG. 9 shows a cerclage device for fractured bones according to a third variant of the second embodiment of the invention;

(11) FIG. 10 shows a cerclage device for fractured bones according to a third embodiment of the invention; and

(12) FIG. 11 shows a cerclage device for fractured bones according to a fourth embodiment of the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

(13) Referring to FIGS. 2-4, there is schematically illustrated a device 1 for the cerclage of a fractured bone 10 according to a first preferred embodiment of the invention.

(14) The cerclage device 1 comprises a cerclage wire 3 and at least one spacer 5 arranged on said cerclage wire 3, said spacer 5 allowing maintaining the cerclage wire 3 at a certain distance from the bone to which the cerclage device 1 is applied, once the cerclage wire is tightened and locked on said bone.

(15) According to the invention, the spacer is made as a band 5 having a substantially rectangular plan and a concave profile.

(16) Thanks to this measure, the force exerted on the fracture bone by the cerclage device 1 is distributed over the entire surface of the band 5.

(17) The band 5 can be made of any material suitable for surgical use, preferably a metal suitable for surgical use or a plastic material suitable for surgical use.

(18) If the band 5 is made of a rigid material, it can be preformed in order to have the desired concave profile.

(19) In the embodiment shown in FIGS. 2-4, the band 5 is made of a material flexible enough to be capable of being deformed for being adapted to the profile of the bone to which the cerclage device 1 is applied (see FIG. 4).

(20) For example, in the embodiment shown in FIGS. 2-4, the band 5 can be made of polyethylene.

(21) Advantageously, owing to the fact that the band 5 has a profile such that it can be adapted to the fractured bone to which the cerclage device 1 is applied, said band will tend to maintain the position assigned thereto and not to move relative to said bone.

(22) As a result, it would be possible to avoid use of dedicated means for locking said band 5 in its desired position (even if said means can however be provided).

(23) In the embodiment illustrated in FIGS. 2-4, the face of the band that, in use, is intended to be in contact with the surface of the fractured bone is smooth.

(24) Thanks to this measure, any risks of rubbing and damaging of the surface of the bone to which the band 5 is applied are avoided.

(25) According to the invention, the band 5 has a pair of end walls 7 that are bent—more particularly, preferably bent at about 90°—and extend in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone, and each of the end walls 7 is provided with a through-hole 11 for the passage of the cerclage wire 3 therethrough.

(26) Still according to the invention, the cerclage device 1, in addition to the cerclage wire 3 on which the band 5 is arranged, comprises a safety thread 13 and, correspondingly, each end wall 7 of the band 5 is provided with an additional through-hole 15 for said safety thread 13.

(27) A stop element 17 is arranged on said safety thread 13, which stop element has a size larger than the size of the additional through-holes 15 of the end walls 17, whereby it cannot pass therethrough and, consequently, the safety thread cannot be removed from the band 5.

(28) The stop element 17 can be provided at an intermediate position of said safety thread 13, between the two end walls 7 of the band 5 (see FIG. 2), or at an end of the safety thread 13 (see the variant of FIG. 3).

(29) Thanks to the safety thread 13, even if the cerclage wire 3 tears off, the band 5 does not risk to become lost in the patient's body.

(30) Advantageously, the additional through-holes 15 have a diameter slightly larger than the diameter of the safety thread 13, such that said safety wire or thread is not subjected to any friction or rubbing and therefore it is not subject to wear. In addition, the safety thread 13 has a length such to be untensioned during normal use of the cerclage device 1, so as not to be subjected to any stresses during said normal use.

(31) In a known and not illustrated manner, one or more cerclage devices 1 of the type described above can be associated with an osteosynthesis plate for forming a cerclage system allowing firm and effective retainment of said plate against the fractured bone, without any risks for the patient.

(32) FIG. 5 illustrates a further variant of the cerclage device of FIGS. 2-4. In this variant, too, the cerclage device 1′ comprises a spacer 5′ in the form of a band, provided with a pair of end walls 7′ bent in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone, said end walls being provided with corresponding through-holes 11′, 12′ for the passage of the cerclage wire (not shown) therethrough.

(33) In this variant, one of the end walls 7′ has a through-hole 11′ which is “closed”, i.e. which is entirely contained within the corresponding end wall; in particular, said through-hole 11′ has a circular profile. The other end wall, instead, has a through-hole 12′ which is open upwards, i.e. which opens on the face of the end wall 7′ opposite to the face of the band 5′ that, in use, is intended to be in contact with the bone.

(34) The through-hole 12′ has substantially the shape of a lying down “C” and has converging upper edges arranged to retain the cerclage wire.

(35) As can be seen in FIG. 5, the additional through-holes 15′ in any case preferably “closed” through-holes, with a substantially circular profile.

(36) Turning now to FIG. 6, there is shown a second preferred embodiment of the invention.

(37) In this embodiment, too, the cerclage device 21 comprises a cerclage wire and at least one spacer 25 arranged on said cerclage wire, said spacer being made as a band 25 having a substantially rectangular plan and a concave profile.

(38) In the embodiment of FIG. 6, said ban 25 is made of a metal suitable for surgical use.

(39) The embodiment of FIG. 6 differs from the first embodiment described above in that the face of the band that, in use, is intended to be in contact with the surface of the fractured bone is provided with teeth 39 projecting from the body of the band 5 in a direction opposite to the end walls 27 of the band, i.e. towards the surface of the fractured bone when the cerclage device 1 is in use.

(40) The teeth 39 might be attached to the surface of the body of the band 25.

(41) However, in the illustrated embodiment, said teeth are obtained directly from the body of said band, by making cuts 41 and bending the portions of the band body thus separated from the rest of said band body.

(42) The teeth 39, in use, contribute to increase the stability of positioning of the band 25 on the fractured bone.

(43) In this embodiment, too, the end walls 27 of the band 25 are provided each with a through-hole 31 for the passage of the cerclage wire therethrough and with one or more additional through-holes 35 for the passage of the safety thread therethrough.

(44) FIGS. 7-9 show respective variants of the second preferred embodiment of the invention of FIG. 5.

(45) In the variant of FIG. 7, the teeth 39 are not obtained by means of cuts in the body of the band 25, but they are arranged along the perimeter of said body.

(46) The teeth 39 can be made integral with the body of the band 25 and then suitably bent.

(47) In the variant of FIG. 8, the band 25 comprises, in addition to the end walls 27, one or more intermediate walls 29 (two in the illustrated example).

(48) Also the intermediate walls 29 extend in a direction opposite to the face of the band that, in use, is intended to be in contact with the surface of the fractured bone, and each of the intermediate walls 29 is provided with a through-hole for the passage of the cerclage wire therethrough, and with one or more additional through-holes for corresponding safety threads.

(49) Said end walls allow guiding the cerclage wire and the safety thread so that they extend substantially parallel to the longitudinal axis of the body of the band 25.

(50) The intermediate walls 29 might be attached to the surface of the body of the band 25.

(51) However, in the illustrated embodiment, they are obtained directly from the body of said band, by making cuts and bending the portions of the band body thus separated from the rest of said band body.

(52) In the variant of FIG. 9, in order to guide the cerclage wire and the safety thread so that they extend substantially parallel to the longitudinal axis of the body of the band 25, there are provided, instead of the intermediate walls of the previous variant, two lateral bent tabs 43, which extend on opposite sides of the body of the band 25 in a direction opposite to the face of said band that, in use, is intended to be in contact with the surface of the fractured bone.

(53) Said lateral tabs 43 arc preferably made integral with the body of the band 25 and then suitably bent.

(54) Turning now to FIG. 10, this illustrates a third preferred embodiment of the invention.

(55) In this embodiment, too, the cerclage device 61 comprises a cerclage wire and at least one spacer 65 made as band having a substantially rectangular plan and a concave profile.

(56) The cerclage device of this embodiment, like the one of the embodiment previously described, further comprises, in addition to the end walls 67 provided with corresponding through-holes 71 for the passage of the cerclage wire of the band therethrough, intermediate walls 69, these, too, being provided with corresponding through-holes 73 for the passage of the cerclage wire of the band therethrough.

(57) In this embodiment, too, the end walls 67 and the intermediate walls 69 are further provided with corresponding additional through-holes 75, 77 for the passage of a safety thread therethrough.

(58) The embodiment of FIG. 10 differs from the previous embodiment in that the face of the band that, in use, is intended to be in contact with the surface of the fractured bone is smooth, like that of the embodiment shown in FIGS. 2-4.

(59) In addition, according to this embodiment, the band 65 is not preformed with a certain concave profile, but it has a substantially flat profile. Said band can subsequently be deformed to obtain, each time, the desired concave profile for the specific application.

(60) Turning now to FIG. 11, there is illustrated a fourth preferred embodiment of the invention.

(61) In this embodiment, too, the cerclage device 81 comprises a cerclage wire and at least one spacer 85 made as a band having a substantially rectangular plan and a concave profile.

(62) The cerclage device of this embodiment, like the one of the previously described embodiment, further comprises, in addition to the end walls 87 provided with the corresponding through-holes 91 for the passage of the cerclage wire of the band therethrough, intermediate walls 89, these, too, being provided with corresponding through-holes 93 for the passage of the cerclage wire of the band therethrough.

(63) In this embodiment, too, the face of the band that, in use, is intended to be in contact with the surface of the fractured bone is smooth and has a flat profile, which can subsequently be deformed to obtain each time a desired concave profile for the specific application.

(64) The embodiment of FIG. 11 differs from the previously described embodiment in that the through-holes 91, 93 provided in the end walls 87 and in the intermediate walls 89, respectively, are not closed, but open upwards, i.e. towards the face of the relevant end wall or intermediate wall opposite to the face of the band that, in use, is intended to be in contact with the surface of the bone.

(65) The through-holes 91, 93 have substantially the shape of a lying down “C” and have converging upper edges arranged to retain the cerclage wire.

(66) In this embodiment, too, the additional through-holes (even if not shown) for the safety wire(s) are, however, preferably “closed” through-holes having a substantially circular profile.

(67) Generally, it is evident that the foregoing detailed description of some preferred embodiments of the invention has been provided by way of non-limiting example and that several variants and modifications are possible without departing from the scope of protection of the present invention as defined in the appended claims.

(68) For example, although the illustrated embodiments refer to a device comprising a cerclage wire, it is evident that said wire might be replaced with a cerclage thread.