WO2022219659A1

WO2022219659A1 - Sternal locking apparatus, forceps for sternal locking apparatus and sternal locking kit

Info

Publication number: WO2022219659A1
Application number: PCT/IT2022/050093
Authority: WO
Inventors: Romolo GAZZANI
Original assignee: Phoenix S.R.L.
Priority date: 2021-04-13
Filing date: 2022-04-12
Publication date: 2022-10-20
Also published as: EP4322876A1; IT202100009149A1

Abstract

Described are an apparatus, a forceps and a sternal locking kit for securing the first and second lateral halves of a longitudinally cut sternum (100); the apparatus comprises an interconnecting bridge element (3), a first and a second sliding body members (1), (2) provided with at least one extension pro j ecting with respect to the interconnecting bridge element (3), such first and second sliding body members (1), (2) being respectively equipped with an elastically deformable lever (11), (21), and designed to position themselves with respect to the interconnecting bridge element (3) by snapping the elastically deformable lever (11), (21) from an initial toothed seat (31) to a final toothed seat (32), the toothed seats (31), (32) shaped to allow sliding only in one direction of the first and second sliding body members (1), (2) blocked in the other direction.

Description

LOCKING APPARATUS AND STERNAL LOCKING KIT

The present invention relates to a sternal locking apparatus.

Furthermore, the present invention relates to a forceps for a sternal locking apparatus.

The present invention also refers to a kit for sternal locking.

In general, the present invention relates to Internal fixation apparatuses, including fixators and spinal fixators, even if a part of them protrudes from the skin for bone cerclage for the sternum, Shape memory effect material properties, Memory materials, Wires, bands or flexible straps, Apparatuses for manipulating flexible wires or belts, Apparatuses for shaping or cutting osteo- synthetic equipment, Tensioning apparatuses, Instruments for placing said fasteners against or away from the bone, Mechanisms for alignment, compression or distraction. In particular, the present invention relates to Fasteners for internal fastening apparatuses with expandable anchors or anchors having moving parts, Cortical plates, i.e. bone plates, and Instruments for holding or positioning cortical plates or for compressing bones attached to cortical plates specially adapted for particular bones for the ribs or sternum.

The state of the art is represented by IT-B1- 1312196 concerning a clip intended for use in cardiac surgery for the synthesis of sternotomy having a generally C-shaped configuration with a core 11 terminating at opposite ends with opposing hooks 12 in which the core 11 centrally extends vertically on a plane substantially perpendicular to that on which the terminal hooks 12 lie with an elastically yielding loop 13, the clip being made with a so-called shape memory metal alloy, i.e. a low-grade malleable alloy temperature, which regains its initial shape at body temperature, exerting a semi-rigid compression on the bone ends that need to be synthesized. The metal alloy is known as NITINOL®. A forceps for applying the clip comprises two levers, 21, 22, hinged together at an intermediate point 23, the levers being provided with respective opposing jaws 25, 26, between which the clip can be inserted, which jaws are provided with means for spreading the loop 13 of the clip into the closing position of the forceps.

Furthermore, the state of the art is represented by patent EP-B1-3137003 concerning a tensioning tool (22) configured to apply a traction force to a portion of an implant (24), the tool (22) comprising: a support member (84) configured to abut on a support surface of the implant (24); an actuator (82) spaced from the support member (84) in a proximal direction (7), the actuator (82) including a flexible portion (89); and a retainer (86) configured to attach to a part of an implant (24), the retainer (86) extending from a position (85) on the actuator (82) towards the support member (84), the position (85) spaced from the carrier (84) a distance in the proximal direction (7), wherein the carrier (84) defines a receptacle (67) which is sized to receive a portion of the retainer (86), in which applying a force to the actuator (82) deforms the flexible part (89) so as to increase the distance between the position and the support member (84), the flexible part (89) including a first driving member (74) and a second driving member (76) which is opposed to the first driving member (74) in a direction which is perpendicular to the proximal direction (7), and the retaining element (86) is disposed between the first driving member (74) and the second driving member (76).

The state of the art is also represented by patent application EP-A1-3389523 concerning a sternal locking unit for fixing the first and second lateral halves of a sternum, comprising a first sliding body having a female portion and a second sliding body having a male portion, the male portion being telescopically mating with the female portion. The male portion is capable of being completely introduced into the female portion only in the presence of an elastic deformation of at least a part of at least one of the male and female portions.

A sternal locking apparatus is known on the market, for example, as FlexiGrip, Sternal Zip-fix, SternFix, which falls under patent IT-B1-1312196. The requirements of a good sternal locking have been achieved in part due to the excellent tightness guaranteed by the use of nickel titanium. The nickel titanium clip does not osteo-integrate, gives great strength, super elasticity, lack of fatigue to loads, and cyclicality; furthermore the memory of the alloy favors surgical access and does not generate artifacts in radiographic images. This means of locking, by hooking the abutments into the intercostal spaces, protect the mammary artery, promote bone growth thanks to its micro elasticity and are suitable for use in bone of any quality. They also provide the possibility of removing a single locking medium in case of dehiscence and replacing it without reopening the entire sternal locking.

The limit of this system is the need to cool the apparatus before inserting it, martensitic phase, and heat it, after its positioning in situ, to allow the recovery of its original geometry, austenitic phase. Furthermore, the choice of as many as ten sizes involves the use of a measuring instrument, slowing down implantation times; finally, the impossibility of applying the apparatus to the handlebar implies a mixed sternal locking with the use of steel wire. The very high price of € 270.00, with the use of 4 staples, greatly limits its use.

The Sternal ZipFix apparatus falls under patent EP-B1-3137003. The requirements of a good locking have been achieved in part by the use of ties with a needle mounted in Peek, which inserted into the intercostal spaces blocked with a dedicated forceps, wrap the sternum stumps. Peek does not osteo-integrate and is radiolucent. The width of the band reduces the crushing lysis between the intercostal spaces and greatly reduces the risk of cutting the osteoporotic bone.

The limit of this system is the non-rapid application that requires extensive tools. This disadvantage is partially offset by the fact that the application technique is very close to the steel wire technique, a positive factor considering the habit of the surgeons. Other limits are found in not being suitable, embracing the sternum, to protect the mammary artery and not being applicable on the handlebar. Also in this case there is no possibility to remove a single locking medium in case of dehiscence, but on the contrary it is necessary to completely reopen the sternal locking. In addition, the system implies, however, a sternal locking mixed with the use of steel wire. The price of € 140 (total price for 4 cable ties), considering the value for money, is very interesting. The SternFix apparatus falls within patent application EP 3389523 A1.

Documents US-A-6 051 007, US-A1-2005 / 240189 and US-A-2007/043371 describe prior art apparatuses. Object of the present invention is solving the aforementioned prior art problems by providing a system suitable for firmly locking the portions of the two hooks, which slide in the joint, when the two hooks are placed extremely close together in the intercostal spaces.

A further object is providing a system suitable for locking the portions of the two hooks while remaining fixed and maintaining a sufficient force equal to or greater than that exerted between the stumps during breathing, coughing and handling the patient, particularly during work activities.

A further object is providing a dedicated forceps, not subject to certification, configured to bring the apparatus open until it is inserted between the intercostal spaces and to guide the gradual sliding in the closing phase.

A further object is providing a forceps, not subject to certification, dedicated to remove the excess connecting portions, once the locking has been consolidated. The above and other objects and advantages of the invention, as will emerge from the following description, are achieved with a sternal locking apparatus, a forceps for a sternal locking apparatus and a kit for the sternal locking described in their respective independent claims.

Preferred embodiments and non-trivial variants of the present invention are the subject matter of the dependent claims. It is understood that all attached claims form an integral part of the present description.

It will be immediately obvious that innumerable variations and modifications (for example relating to shape, dimensions, arrangements and parts with equivalent functionality) can be made to what is described, without departing from the scope of the invention as appears from the attached claims.

As advantageous effects of the invention, the apparatus object of the invention has the advantage of being easy to apply, not being subject to osteo- integration, capable of removing a single locking medium in case of dehiscence by carrying out the replacement without reopening the entire sternal locking, guaranteeing a protection of the mammary artery and to be radiolucent through the use of material known as Peek Optima.

The present invention will be better described by some preferred embodiments thereof, provided by way of non-limiting example, with reference to the attached drawings, in which:

FIG. 1 shows an axonometric view of an embodiment of the sternal locking apparatus according to the present invention; FIG. 2 shows a side view of the previous figure;

FIGS. 3 and 4 show a sectional view in two configurations along lines III-III, IV-IV of the previous figure; FIG. 5 shows an axonometric view of a relevant part of an embodiment of the sternal locking apparatus according to the present invention;

FIG. 6 shows a side view of the previous figure; FIG. 7 shows a section view along line VII-VII of the previous figure;

FIG. 8 shows an axonometric view of a further relevant part of an embodiment of the sternal locking apparatus according to the present invention; FIG. 9 shows a plan view of the previous figure;

FIG. 10 shows a section view along line X-X of the previous figure; FIG. 11 shows a side view of FIG. 8; and

FIG. 12 and FIG. 13 show two configurations of an implementation of the apparatus made operational by the forceps object of the present invention.

Referring to FIG. 1, it is possible to note that a sternal locking apparatus for fixing the first and second lateral halves of a longitudinally cut sternum 100, comprises a first and a second sliding body members 1, 2 and an interconnecting bridge element 3. The first and second sliding body members 1, 2 are provided with at least one extension projecting with respect to the interconnecting bridge element 3 configured to abut on an outer edge of the first and second lateral halves of the sternum. Advantageously, referring to FIGS. 3, 4, at least one of the first and second sliding body members 1, 2 is positioned with respect to the interconnecting bridge element 3 by triggering an elastically deformable lever 11, 21 from an initial toothed seat 31 to a final toothed seat 32. The toothed seat 31, 32 are shaped to allow sliding only in one direction of the first or second sliding body member 1, 2 locked in the other direction. In particular, the elastically deformable lever 11, 21 is not deformed when it is locked in the toothed seat 31, 32.

With reference to Figures 5 to 7, the elastically deformable lever 11, 21 belongs to the first and second sliding body members 1, 2.

With reference to Figures 8 to 11, the toothed seat 31, 32 is part of a plurality of toothed seats distributed along a portion of the interconnection bridge element 3 to allow an optimal range of extension, the toothed seats arranged orthogonally to the direction of relative linear scrolling.

The first and second sliding body members 1, 2 comprise a guide tunnel 12, 22 configured to be able to receive the interconnecting bridge element 3 allowing relative linear sliding, while the interconnecting bridge element 3 consists of a longitudinal bar.

The guide tunnel 12, 22 consists of a rigid C- shaped cavity bounded on the open side by said elastically deformable lever 11, 21. The elastically deformable lever 11, 21 is shaped to enter the guide tunnel 12, 22 when the lever elastically deformable 11, 21 is not deformed, in order to be able to receive the interconnection bridge element 3 allowing relative linear sliding.

In particular, the interconnection bridge element 3 consists of a longitudinal bar.

The interconnection bridge element 3 is equipped with aid means 33 to facilitate the sternal locking operations.

Preferably, the apparatus is made of a material capable of providing artifact-free images and unobstructed views when using X-ray, CT and MRI imaging techniques. Referring to FIG. 12 and 13, an auxiliary forceps 200 in sternal locking operations by means of a sternal locking apparatus for securing the first and second lateral halves of a longitudinally cut sternum 100 comprises a centering element 201 configured to control the positioning of the apparatus 100 during a sliding and interconnection by means of an operative coupling between the centering element 201 and the auxiliary means 33, the forceps being designed to engage the first and second sliding body members 1, 2 at their ends to push them from the initial toothed seats 31 to the final toothed seats 32 to make the sternal locking.

A kit for practicing sternal locking to secure the first and second lateral halves of a longitudinally cut sternum consists of a sternal locking apparatus and an auxiliary forceps as described above.

In particular, the sternal locking apparatus includes at least one apparatus 100 and an auxiliary forceps 200 as described above.

Claims

1. Sternal locking apparatus for securing the first and second lateral halves of a longitudinally cut sternum (100), comprising an interconnecting bridge member (3), first and second sliding body members (1), (2) designed to operatively couple and slide along said interconnecting bridge element (3), said first and second sliding body members (1), (2) being provided with at least one extension projecting with respect to the interconnecting bridge element (3) configured to abut on an outer edge of the first and second lateral halves of a sternum, characterized in that said first and second sliding body members (1), (2) are respectively equipped with an elastically deformable lever (11), (21), said first and second sliding body members (1), (2) being designed to position themselves with respect to the interconnecting bridge element (3) by snapping said elastically deformable lever (11), (21) from an initial toothed seat (31) to a final toothed seat (32), said toothed seats (31), (32) shaped to allow sliding only in one direction of the first and second sliding body members (1), (2) stuck in the other direction.

2. Apparatus according to the preceding claim, characterized in that the elastically deformable lever (11), (21) when locked in the toothed seat (31), (32), is not deformed.

3. Apparatus according to one of the preceding claims, characterized in that the toothed seats (31), (32) are part of a plurality of toothed seats distributed along a portion of the interconnecting bridge element (3) to allow an extended excursion, the toothed seats (31), (32) arranged orthogonally to the relative linear sliding direction.

4. Apparatus according to one of the preceding claims, characterized in that each of the first and second sliding body members (1), (2) comprises a guide tunnel (12), (22) configured to be able to receive the interconnection bridge element (3) allowing relative linear sliding, while the interconnection bridge element (3) consists of a longitudinal bar.

5. Apparatus according to the preceding claim, characterized in that the guide tunnel (12), (22) consists of a rigid C-shaped cavity delimited on the open side by said elastically deformable lever (11), (21), the elastically deformable lever (11), (21) shaped to enter the guide tunnel (12), (22) when the elastically deformable lever (11), (21) is not deformed, in order to receive the interconnecting bridge element (3) allowing relative linear sliding, the interconnecting bridge element (3) consisting of a longitudinal bar.

6. Apparatus according to one of the preceding claims, characterized in that the interconnecting bridge element (3) is equipped with auxiliary means (33) to facilitate the sternal locking operations.

7. Apparatus according to one of the preceding claims, characterized in that it is made of a material capable of providing artifact-free images and unobstructed views when X-ray, CT and MRI imaging techniques are used.

8. Forceps (200) auxiliary in the operations of sternal locking by means of a sternal locking apparatus for fixing the first and second lateral halves of a longitudinally cut sternum (100) of the type according to one of the preceding claims, characterized in that it comprises a centering element (201) configured to control the positioning of the apparatus

(100) during a sliding and an interconnection by means of an operative coupling between said centering element (201) and said auxiliary means (33), said forceps being designed to engage at its own ends of said first and second elements of a sliding body (1), (2) to push them from said initial toothed seats (31) to said final toothed seats (32) to achieve sternal locking. 9. Kit for practicing sternal locking to fix the first and second lateral halves of a longitudinally cut sternum, consisting of a sternal locking apparatus and an auxiliary forceps, the sternal locking apparatus comprising at least one apparatus (100) according to any one of claims 1 to 7, and the auxiliary forceps (200) according to claim 8.