FR3042965A1 - ANCHOR FOR MEDICAL USE INTENDED TO BE INSERTED IN A BONE WALL - Google Patents

Abstract

This anchor comprises two parts (2, 3) intended to be assembled to one another, namely: - an outer part (2), intended to be fixed to the bone, which forms a cavity (6) to the interior of it and at least a first wedging surface (14), proximal; and an inner piece (3), intended to be inserted and retained in said outer piece (2), which forms a transverse duct (22) at its proximal end and at least a second wedging surface (20) located proximal side with respect to this conduit (22); the inner part (3) is movable between a partial engagement position in the outer part (2), wherein said transverse duct (22) is outside the cavity (6) formed by the outer part (2), and a fully engaged position in this outer piece (2), wherein the strand of a suture engaged in said duct (22) is crushed between the two wedging surfaces (14, 20).

Description

The present invention relates to an anchor for medical use, intended to be inserted into a bone wall.

This anchor is intended in particular to allow the reinsertion of a tendon or a ligament on a bone; it is particularly intended to re-insert on one humerus one or more tendons of the rotator cuff of the shoulder joint.

It is well known, in various indications, to reinsert a tendon or a ligament on a bone by means of an anchor inserted into the bone, connected to one or more suture threads, this or these son making it possible to suture the tendon or ligament to the bone.

To connect the suture to an anchor, it is known to provide a transverse passage arranged through the anchor, wherein the suture is engaged. This type of assembly has the disadvantage of making a passage of the suture son strands along the anchor, and thus more or less crush these strands between the anchor and the bone wall during the establishment of anchor. This results in a deterioration of the structure of the wire during the screwing or the impaction of the anchor in the bone, which can lead to a breakage of this wire.

It is also known to provide a proximal ring on an anchor, to which the suture is tied. This type of anchor also has a significant risk of breaking the wire at the node.

To remedy this drawback, knotless anchors have been designed in which the yarn is held on the anchor by pinching or jamming. However, these anchors do not exclude any risk of deterioration of the wire during the installation of the anchor, particularly when the latter is screwed, or severing the wire at its connection point to the anchor, which it results in the same risk of breaking the wire.

The present invention aims to remedy this essential disadvantage.

In addition, a number of existing anchors have a relatively uncertain pull-out resistance. This problem arises in particular for anchors intended for the reinsertion of tendons of the rotator cuff of a shoulder joint, taking into account the significant tension exerted on the suture son or sutures, and therefore on the one or more anchors, by these tendons during the movement of the joint.

The present invention also aims to remedy this drawback. The main objective of the invention is therefore to provide an anchor to which one or more suture son can be perfectly fixed and retained, with a reduced risk of shearing or breaking of this or these son.

Another object of the invention is to provide an anchor capable of being perfectly fixed to a bone wall.

To achieve at least the principal objective mentioned above, the anchor concerned comprises two pieces intended to be assembled to one another, namely: an outer part, intended to be fixed to the bone, which forms a cavity inside her; this outer part forms, at the level of the proximal zone of said cavity, at least a first wedging surface; and an inner part, intended to be inserted and retained in said outer part, which forms a transverse duct at its proximal end and at least a second wedging surface located on the proximal side relative to this duct; the inner part is movable between a position of partial engagement in the outer part, in which said transverse duct is outside the cavity formed by the outer part, and a position of complete engagement in this outer part, in which this transverse duct is in said cavity and in which said second wedging surface is opposite said first wedging surface, the distance between this first wedging surface and this second wedging surface being, in this position, such that the strand a suture engaged in said transverse duct is crushed between these two surfaces.

In practice, one or more suture son are engaged through said transverse duct while said inner part is in said partial engagement position, then the inner part is brought into full engagement position in the outer part, realizing the crushing the strand (s) of the suture (s) between said wedging surfaces, and thus making the assembly of this or these son to the anchor.

This crushing allows a perfect connection of the son or sutures to the anchor, without substantial deterioration of the structure of this or these son, and therefore without substantially reducing the resistance thereof.

It will be understood that the terms "proximal" and "distal" used above and throughout the present description are to be considered in relation to the direction of insertion of the anchor into a bone wall, the term "proximal" designating a location closer to an operator with respect to this direction of insertion and "distal" designating a location further from this operator with respect to this same direction of insertion.

Preferably, at least one of the two wedging surfaces is bordered by two ribs having a height such that they laterally close the space delimited by the wedging surfaces between them.

These ribs thus make it possible to contain between them and to guide the strand (s) of the suture (s) situated between the two wedging surfaces.

According to a preferred embodiment of the invention, in this case, - said ribs are parallel to the direction of movement of said inner part relative to said outer part between said positions of partial engagement and full engagement of these parts ; one of the two wedging surfaces is bordered by said ribs, and the other wedging surface is bordered by two corresponding grooves in which these ribs are slidably engaged.

Preferably, said outer part has an oblong shape in cross section, in particular annular. The anchor is thus adapted to be engaged in an oblong hole of shape corresponding to that of the outer part, arranged in the osseous wall, then to be rotated over a quarter turn so as to be perfectly wedged in this hole.

Advantageously, in this case, the outer part has anchoring asperities at its two opposite sides farthest from each other, that is to say those coming into the bone wall to the result of pivoting over a quarter of a turn. These asperities can in particular be in the form of stepped transverse ribs.

A perfectly resistant anchorage can thus be obtained.

Preferably, said outer part and said inner part comprise a first assembly system from one to the other including: a transverse hooking flange arranged on one side of said outer part, this edge being preceded, on the proximal side by an inclined wall forming a ramp; - An opening on the opposite side of said outer part, opening on the outside of this room; - A bent distal portion arranged on the inner part, forming a hook adapted to engage with said transverse hooking flange; - A thinned central part of this inner part, conferring a capacity for elastic deformation, in the transverse direction, the distal portion of the inner part relative to the proximal portion of this inner part.

The ramp laterally deflects said distal portion when the inner part engages the outer part to allow engagement of the bent distal portion about said transverse hooking flange, and said opening forms a recess thereby possible deviation.

Preferably, said outer part and said inner part comprise a second assembly system from one to the other, including: a flexible locking tongue, arranged on the outer part, forming a transverse distal face; - A transverse locking face, arranged on the inner part, turned proximally, and - a distal ramp arranged on the inner part beyond said transverse locking face, for lifting said flexible tongue when moving the workpiece interior to said full engagement position, this flexible tongue snapping behind said transverse locking face when the inner part reaches its full engagement position in the outer part.

This second assembly system, with the first assembly system, allows a perfectly resistant assembly of said inner part to said outer part notwithstanding the reduced dimensions of the anchor. This perfectly resistant assembly makes it possible, particularly when the outer part is intended to be wedged in the receiving hole by pivoting over a quarter of a turn, to give the anchor according to the invention high anchorage reliability, making this anchor well adapted to the re-insertion of a tendon or ligament into a bone, particularly one or more tendons forming part of the rotator cuff of the shoulder joint.

Preferably, the outer part forms an elongate guide window, delimited, on the proximal side, by a transverse flange, and the inner part has a projection engaged and able to slide in this window, this projection being positioned so as to abut against said transverse flange when the inner part is in said partial engagement position. The engagement of this projection in this window ensures an assembly of the inner part to the outer part, and the coming of the projection abutting against said transverse flange defines said partial engagement position.

Preferably, the outer part has an unlocking window arranged below said transverse hooking flange, for acting on the hook formed by said curved distal portion of the inner part, so as to release this hook from its engagement position. vis-à-vis said transverse hooking flange.

The inner part can thus be returned to the partial engagement position, if necessary. The invention, as described above, will be well understood, and other features and advantages thereof will appear, with reference to the attached schematic drawing, which represents, by way of non-limiting example, a form of preferred embodiment of the anchor concerned.

Figure 1 is a perspective view, with an inner part that includes partially engaged in an outer part that it also includes; Figure 2 is a longitudinal sectional view, the inner part being out of the outer part; Figure 3 is a view similar to Figure 2, said inner part being in the same partial engagement position as in Figure 1; Figure 4 is a view similar to Figure 1, after establishment of suture son and in a position of full engagement of the inner part in the outer part; and FIG. 5 is a view similar to FIG. 3, in this same fully engaged position.

The figures represent an anchor 1 for medical use, intended to be inserted into a bone wall. This anchor is particularly intended to re-insert on one humerus one or more of the tendons of the rotator cuff of the shoulder joint. The anchor 1 comprises an outer part 2 and an inner part 3 intended to be assembled to one another.

The outer part 2 is intended to be fixed to the bone. It has an annular cross-sectional shape, having two substantially flat opposed sides and two rounded opposite sides, the two planar sides being closer to one another than the two rounded sides.

These two rounded sides have series of notches side-by-side, staggered along the length of the part 2, which delimit between them ribs 5 forming anchoring asperities to the bone.

The part 2 forms a cavity 6 inside it, which opens into the proximal face 2a of the part 2 and which opens on a plane side of the part 2, at the distal level thereof, through an opening 7 .

Below this opening 7, the part 2 forms a sloping wall 10, slightly curved, which constitutes a sliding ramp, connected on the distal side to a transverse hooking rim 11.

On the opposite side to the opening 7, the part 2 has a window 12 situated below the rim 11.

On the proximal side relative to the opening 7, the part 2 has a U-shaped cut-out individualizing a flexible tongue 13, which is elastically deformable between a state of non-deformation visible in FIGS. 2, 4 and 5 and a state of visible deformation. in Figures 1 and 3.

On the proximal side relative to the tongue 13, and below the opening through which the cavity 6 opens into the proximal face 2a, the part 2 forms on one side a flat surface 14 bordered by two grooves (not referenced; Figure 1). These two grooves are parallel to each other and parallel to the direction of movement of the part 3 relative to the part 2 between said partial engagement and full engagement positions.

On the proximal side and on the opposite side to this surface 14, the part 2 forms an elongate window 15, opening on the outside. The window 15 does not open into the proximal face 2a of the part 2, so that, on the proximal side, this window 15 is delimited by a transverse rim formed by the piece 2. At its distal end portion, the piece 2 form a tip 16 promoting its introduction and its impaction in the hole in a bone to receive it.

The inner part 3 is intended to be inserted and retained in the cavity 6, and is therefore movable relative to the part 2 between a partial engagement position in this part 2, visible in FIGS. 1 and 3, and a position of full engagement in this piece 2, visible in Figures 4 and 5.

From the proximal side to the distal side, the piece 3 has: a flat surface 20 intended to face the surface 14 in said fully engaged position; - Two ribs 21 laterally bordering the surface 20, which are slidably engaged in the aforementioned grooves formed by the part 2; - A transverse duct 22, through which are intended to be engaged one or more, including two s son F suture of one or more tendons or ligaments; - A guide projection 23, intended to be latched in the window 15; - At the median level, the side intended to be under the tongue 13, a recess 24 defining a shoulder 25 facing the proximal side; - below the recess 23, a recess 26 making the piece 3 has a thinned central portion, this thinned central portion imparting an elastic deformation capacity, in the transverse direction, to the distal portion of the piece 3 with respect to the proximal part of this piece; - A curved distal portion 27 forming a hook adapted to engage with said transverse hooking flange; - Two rounded distal surfaces 28, 29, one of which allows the lifting of the tongue 13 during the insertion of the piece 3 into the cavity 6 and the other allows the sliding of the piece 3 on the ramp formed by the wall .

With particular reference to Figures 1 and 4, it appears that the proximal portion of the part 3, namely that which forms the surface 20 and through which is arranged the conduit 22, has a width substantially smaller than that of the cavity 6 below the proximal face 2a, so that there are spaces on either side of this proximal portion, allowing the engagement of junction parts that form an instrument (not shown) for capturing and impinging the anchor 1.

In practice, the parts 2 and 3 being in the partial engagement position shown in FIGS. 1 and 3, two suture threads F are engaged through the transverse duct 22 and then the piece 3 is brought into the fully engaged position in FIG. the piece 2. At the end of the displacement of the part 3, the hook portion 27 comes into engagement around the flange 11 and the distal transverse flange of the tongue 13 simultaneously engages in the recess 24 and against the shoulder 25 This displacement also carries out the crushing of the strands of the suture threads F between the surfaces 14 and 20, and thus makes, by wedging these strands between these surfaces, the assembly of the threads F at the anchor 1.

The ribs 21 can laterally close the space defined by the surfaces 14 and 20 between them and thus allow to contain and guide the strands of son F in this space. The anchor 1, thus connected to the son F, is then engaged in an oblong hole of shape corresponding to that of the piece 2, arranged in the bone wall, then is rotated over a quarter of a turn so as to be perfectly stuck in this hole. During this pivoting, the ribs 5 bite into the bone wall.

The double assembly means that constitutes the portion 27 and the flange 11, on the one hand, and the tongue 13 and the shoulder 25, on the other hand, allow a perfect assembly of the piece 3 to the piece 2. L anchor 1 is thus able to withstand very strong traction, especially those exerted by one or more tendons of the rotator cuff on the son and on the anchor. The crushing of the strands of the son F allows a perfect connection of these son to the anchor 1, without substantial deterioration of the structure of these son, and therefore without substantially lessening the resistance thereof.

It thus appears that the invention provides an anchor 1 for medical use having decisive advantages, supra, compared to homologous anchors of the prior art.

This anchor 1 has been described above with reference to a preferred embodiment; it goes without saying that this description is in no way limiting.

Claims (10)

1. Anchor (1) for medical use, intended to be inserted into a bone wall, characterized in that it comprises two parts (2, 3) intended to be assembled to one another, namely: - a an outer piece (2) for attachment to the bone which forms a cavity (6) therein; this outer piece (2) forms, at the level of the proximal zone of said cavity (6), at least a first wedging surface (14); and an inner piece (3), intended to be inserted and retained in said outer piece (2), which forms a transverse duct (22) at its proximal end and at least a second wedging surface (20) located proximal side with respect to this conduit (22); the inner part (3) is movable between a partial engagement position in the outer part (2), wherein said transverse duct (22) is outside the cavity (6) formed by the outer part (2), and a position of complete engagement in this outer part (2), wherein this transverse duct (22) is in said cavity (6) and wherein said second wedging surface (20) is opposite said first surface wedging device (14), the distance between this first wedging surface (14) and this second wedging surface (20) being, in this position, such that the strand of a suture (F) engaged in said transverse conduit (22) is crushed between these two surfaces. 2. Anchor (1) according to claim 1, characterized in that at least one of the two wedging surfaces (20) is bordered by two ribs (21) having a height such that they laterally close the space delimited by the wedging surfaces (14, 20) therebetween. 3. Anchor (1) according to claim 2, characterized in that: - said ribs (21) are parallel to the direction of movement of said inner part (3) relative to said outer part (2) between said positions of partial commitment and full commitment of these parts; - One of the two wedging surfaces (20) is bordered by said ribs (21), and the other wedging surface (14) is bordered by two corresponding grooves in which these ribs (21) slide. 4. Anchor (1) according to one of claims 1 to 3, characterized in that said outer member (2) has an oblong shape in cross section, in particular annular. 5. Anchor (1) according to claim 4, characterized in that the outer part (2) has anchoring asperities (5) at its two opposite sides farthest from each other. 6. Anchor (1) according to claim 5, characterized in that said asperities are in the form of transverse ribs (5) staggered. 7. Anchor (1) according to one of claims 1 to 6, characterized in that said outer part (2) and said inner part (3) comprise a first assembly system from one to the other, including a transverse hooking lip (11) arranged on one side of said outer part (2), this rim (11) being preceded, on the proximal side, by an inclined wall (10) forming a ramp; - An opening (7) arranged on the opposite side of said outer part (2), opening on the outside of this room; - A curved distal portion (27) arranged on the inner part (3) forming a hook adapted to engage with said transverse hooking flange (11); - A thinned central part of this inner part (3), conferring a resilient deformation capacity, in the transverse direction, to the distal portion of the inner part (3) relative to the proximal portion of this inner part (3). 8. Anchor (1) according to one of claims 1 to 7, characterized in that said outer part (2) and said inner part (3) comprise a second assembly system from one to the other, including a flexible locking tongue (13) arranged on the outer part (2), forming a transverse distal face; - a transverse locking face (25) arranged on the inner part (3), turned on the proximal side, and - a distal wall (28) arranged on the inner part (3) beyond said transverse locking face ( 25) for lifting said flexible tongue (13) as the inner part (3) moves towards said fully engaged position, said flexible tongue (13) snapping behind said transverse locking face (25) when the inner part (3) reaches its fully engaged position in the outer part (2). 9. Anchor (1) according to one of claims 1 to 8, characterized in that the outer part (2) forms an elongated guide window (15) delimited, on the proximal side, by a transverse flange, and the workpiece interior (3) has a projection (23) engaged and slidable in this window (15), this projection (23) being positioned to abut against said transverse flange when the inner part (3) is in said position partial commitment. 10. Anchor (1) according to one of claims 7 to 9, characterized in that the outer part (2) has an unlocking window (12) arranged below said transverse hooking flange (11), to act on the hook formed by said curved distal portion (27) of the inner part (3), so as to release this hook from its engagement position vis-à-vis said transverse hooking flange (11).