FR3118405A1 - Ancillary for bone surgery, suitable for the compression of a hinge between two bone fragments during an osteotomy technique - Google Patents

Abstract

The present invention relates to an ancillary device for bone surgery, intended to be attached to an osteosynthesis plate (P) positioned on the bone (S) of a patient, for the compression of a bone hinge (C). The ancillary comprises: (i) a base (2) comprising means for assembly with said osteosynthesis plate (P), (ii) a lever (3), attached through a first through hole (26) of said base (2) and comprising a rear section intended to be inserted into one of the two bone fragments (F1, F2), which lever (3) and which first through hole (26) cooperate via means of assembly (5) allowing at least one degree of freedom in rotation of said lever (3) about an axis of rotation (R), and (iii) maneuvering means (4), for the rotational maneuver of said lever (3 ) around said axis of rotation (R). Figure for abstract: 14

Description

Ancillary for bone surgery, suitable for the compression of a hinge between two bone fragments during an osteotomy technique

Technical field of the invention

The present invention relates to the general field of orthopedic surgery.

It relates in particular to ancillaries for bone surgery, intended to be attached to an osteosynthesis plate positioned on the bone of a patient, suitable for the compression of a hinge between two bone fragments during an osteosynthesis technique. osteotomy, in particular an opening osteotomy technique.

State of the art

Osteotomy refers to the surgical section of a long bone, to modify its axis, size or shape, for therapeutic or plastic purposes.

Among the osteotomy techniques, the so-called "opening osteotomy" techniques are known in particular, which consist in cutting the bone to be treated with a cutting line, then in separating the edges of the line by introducing a bone wedge. or artificial (metal, cement, bone substitute).

Once the correction has been obtained, the two bone fragments are firmly held by osteosynthesis material, in particular an osteosynthesis plate secured to the bone by means of screws.

Such a surgical intervention is for example useful to treat certain osteoarthritis localized at the knee, in order to correct a deformity of the lower limb and to obtain a straightening of the tibia or the femur. In particular, tibial valgus osteotomy remains the intervention of choice for the treatment of internal femoro-tibial osteoarthritis on the genu varum.

In practice, the cut line is made in the bone while preserving an intact part connecting the two fragments: the bone hinge. Predicting and preserving this bony hinge makes it possible to preserve the correction and facilitate consolidation.

But, a risk of rupture or weakening of this hinge is likely to occur at this hinge during the intervention, the opening being controlled manually by the practitioner.

However, such a lesion generally leads to correction and/or consolidation problems for the patient.

There is therefore a need for a technical solution that would allow the operator to mitigate / remedy, at least partially, the consequences of this breakage / weakening of the hinge.

Presentation of the invention

In order to remedy the aforementioned drawback of the state of the art, the present invention proposes an ancillary device for bone surgery, intended to be attached to an osteosynthesis plate positioned on the bone of a patient, for setting compression of a hinge (weakened or broken) between two bone fragments during an osteotomy technique, in particular an opening osteotomy technique.

More particularly, according to the invention, an ancillary is proposed which comprises:

(i) a base comprising:

- a rear face adapted to be positioned facing a surface of said bone and/or said osteosynthesis plate,

- assembly means with said osteosynthesis plate, and

- at least a first through hole, intended to come opposite one of said two bone fragments,

(ii) a lever, inserted through said at least one first through hole of said base,

which lever comprises a rear section intended to extend from the side of said rear face and to be inserted into one of the two bone fragments,

which lever and which first through hole cooperate by means of assembly means allowing at least one degree of freedom in rotation of said lever around an axis of rotation located at said base, advantageously extending parallel with respect to the general axis of the bony hinge, and

(iii) operating means, for the rotational operation of said lever around said axis of rotation.

The ancillary device according to the invention constitutes a technical solution which allows the practitioner to alleviate/remedy, at least partially, the consequences of a rupture/weakening of the bone hinge.

Indeed, in the presence of such a break / weakening during the intervention, the practitioner can implement the ancillary according to the invention so as to compress the bone hinge.

For this, the operator fixes the base of the ancillary in a first bone fragment and implants the rear section of the lever in a second bone fragment, then applies a rotational maneuver to this lever around its axis of rotation. An osteosynthesis plate is then attached to the two bone fragments so as to maintain the compression of the hinge.

This compression of the bone hinge makes it possible to maintain the correction while compressing the hinge in order to facilitate consolidation.

According to a preferred embodiment, the lever comprises:

- a lever rod, attached through the first through hole of the base and forming the rear section of the lever, and

- a lever guide, tubular, which is intended to receive the rod and which forms part of the assembly means and/or part of the operating means.

Still according to a preferred embodiment, the lever comprises a front section, intended to extend from the side of a front face of said base, which cooperates with the maneuvering means for the rotational maneuver of said lever.

The operating means advantageously include:

- a slider carried by the front section of the lever, advantageously carried by the lever guide,

- A slide carried by the base, cooperating with said slider for guiding it in translation.

The slider defines a slider travel which has the shape of an arc of a circle whose center is crossed by the axis of rotation.

Other non-limiting and advantageous characteristics of this embodiment in accordance with the invention, taken individually or according to all the technically possible combinations, are the following:

- The maneuvering means comprise a system for maneuvering the slide along the length of the slide, advantageously a system of the pinion/rack type; in the presence of the pinion/rack type system, the slide advantageously comprises a transverse slot in an arc of a circle whose center is crossed by the axis of rotation and which is provided with said rack, and the slider carries said pinion, movable in rotation to ensure the path of said slide along said slide;

- the slide has a front light, intended to be crossed by the front section of the lever, advantageously by the rod, and oriented perpendicularly with respect to the axis of rotation;

- the slide is carried by the base, opposite and at a distance from a front face of said base; the slide and the base are advantageously assembled by means of interlocking means;

- the slide and the base cooperate through assembly means allowing at least two positions of said slide relative to said base.

Other non-limiting and advantageous characteristics of the product in accordance with the invention, taken individually or in all technically possible combinations, are as follows;

- the assembly means between the lever (advantageously the lever guide) and the first through hole consist of an assembly forming a ball joint; where applicable, the lever guide advantageously comprises a first end carrying the slider and a second end having the shape of a spherical cap cooperating with a bearing surface of the first through orifice of the base;

- the ancillary comprises means for locking the lever in rotation around its axis of rotation, advantageously a screw carried by the slide and adapted to cooperate with the slide;

- the rear face of the base comprises a support portion adapted to be positioned against said osteosynthesis plate, and the ancillary comprises at least one through hole provided opposite said support portion, intended to receive means of temporarily implantable fixation in a through hole of said osteosynthesis plate, for the temporary fixation of said ancillary on said osteosynthesis plate and even in said bone; said ancillary advantageously comprises said first through orifice, receiving said lever, and two through orifices formed facing said bearing portion, each intended to come facing one of said two bone fragments.

The present invention also relates to equipment for bone surgery, suitable for the implementation of an osteotomy technique, in particular an opening osteotomy technique.

The material includes:

- an ancillary according to the invention,

- an osteosynthesis plate provided with two groups of through holes, one proximal and the other distal, each of said groups being intended to accommodate fixing screws intended to be implanted in one of the two bone fragments,

- means for temporarily attaching said ancillary to said osteosynthesis plate,

- a set of said fixing screws, intended to be inserted through the through holes of said osteosynthesis plate and to be implanted in the bone fragments, and

- preferably an olive pin, intended to be positioned in one of the through holes of the osteosynthesis plate and to be temporarily inserted into the opposite bone fragment.

The present invention also relates to a method for an osteotomy technique, in particular an opening osteotomy technique, which method comprises:

- a step of cutting the bone (osteotomy), to form a hinge connecting two bone fragments,

- a bone opening step, during which the state of the hinge is assessed,

- a first stage of partial fixing of the osteosynthesis plate, by inserting the fixing screws through a first group of through holes and so that they penetrate into a first bone fragment,

- a temporary fixing step of the base of the ancillary on the osteosynthesis plate positioned on the bone, with placement of the rear section of the lever in one of the two bone fragments,

- a step of compressing the hinge by rotating the lever around its axis of rotation,

- a second step of fixing the osteosynthesis plate by inserting the fixing screws through a second group of through holes and so that they penetrate into the second bone fragment,

- an ancillary removal step.

Of course, the different characteristics, variants and embodiments of the invention can be associated with each other in various combinations insofar as they are not incompatible or exclusive of each other.

Detailed description of the invention

In addition, various other characteristics of the invention emerge from the appended description made with reference to the drawings which illustrate non-limiting forms of embodiment of the invention and where:

is a schematic view in perspective of surgical equipment in accordance with the invention, the ancillary device according to the invention of which is juxtaposed with an osteosynthesis plate positioned on an “open” bone comprising a bone hinge;

is an exploded view in perspective of the ancillary according to the ;

is an assembled and perspective view of the ancillary according to the ;

is still an assembled view, from another perspective, of the ancillary according to the ;

is an isolated and enlarged view of the constituent base of the ancillary according to the ;

is an isolated and enlarged view of a slide making up the ancillary according to the ;

is an isolated and enlarged view of a lever guide constituting the lever of the ancillary according to the ;

is an isolated and enlarged view of a constituent rod of the ancillary lever according to the ;

is a view of a step in a method for an osteotomy technique, with partial fixation of the osteosynthesis plate on a first bone fragment;

is a view of a step in a process for an osteotomy technique, with temporary fixation of the ancillary on the osteosynthesis plate positioned on the bone;

is a view of a step in a method for an osteotomy technique, with adjustment of the inclination of the lever guide before the compression of the hinge;

is a view of a process step for an osteotomy technique, with placement of the lever rod in a second bone fragment;

is another view of the process step according to ;

is a view of a step in a method for an osteotomy technique, with compression of the hinge by a rotational maneuver of the lever around its axis of rotation;

is a view of a step in a process for an osteotomy technique, with fixation of the osteosynthesis plate in the second bone fragment and removal of the ancillary;

is an isolated and enlarged view of a variant of the constituent base of the ancillary;

shows an alternative embodiment for the slide/lever guide couple, constituting the ancillary;

is an isolated view of an olive pin for the surgical material according to the invention;

is a view of a step of a method for an osteotomy technique, with compression of the hinge with surgical material according to Figures 16 to 18.

It should be noted that, in these figures, the structural and/or functional elements common to the different variants may have the same references.

The ancillary 1 according to the invention, one embodiment of which is illustrated in the figures, is useful in bone surgery techniques in order to ensure the compression of a bone hinge C connecting the two bone fragments F1, F2 making up the S bone of a patient.

Such ancillary 1 is advantageously intended to be attached to an osteosynthesis plate P positioned on the bone S of a patient in order to assist the surgeon in an osteotomy technique (in particular an opening osteotomy technique ) in the event of weakening or rupture of the bone hinge C.

By "opening osteotomy", we mean a surgical procedure consisting of cutting a patient's bone with a cutting line, then spreading the edges of the line by introducing a bone or artificial wedge (metal, cement, bone substitute).

This surgical technique can be used to treat different bones in the human body.

Such a surgical intervention is for example useful to treat certain osteoarthritis localized at the knee, in order to correct a deformity of the lower limb and to obtain a straightening of the tibia or the femur. In particular, tibial valgus osteotomy remains the intervention of choice for the treatment of internal femoro-tibial osteoarthritis on the genu varum.

Osteosynthesis plate

At the outset and in general, the osteosynthesis plate P is intended to be fixed with the two bone fragments F1, F2, following the osteotomy technique, so as to freeze the correction made by the surgeon.

Such an osteosynthesis plate P is for example described in detail in the document FR2980967.

This osteosynthesis plate P consists of two elongated parts P1, P2, which are each intended to be joined with one of the two bone fragments F1, F2.

The osteosynthesis plate P, here presenting a general L-shape, thus comprises:

- a first part P1 (here proximal) intended to be positioned against a first fragment F1 (here proximal) of bone S, and

- a second part P2 (here distal) intended to be positioned against a second fragment F2 (here distal) of this same bone S.

Each of these two parts P1, P2 (first/second) is provided with a group of through holes P11, P21 for receiving fixing screws V in one of the bone fragments F1, F2.

Ancillary

The ancillary 1 according to the invention, generally illustrated in Figures 2 to 4, generally comprises:

- a base 2, also called "compression guide", intended to be assembled with the osteosynthesis plate P partially fixed on the bone S, with one of the two fragments, here in the first fragment F1,

- a lever 3, intended to be inserted in another of the two bone fragments, here in the second fragment F2, and cooperating with the base 2 to confer an axis of rotation R to said lever 3, and

- Maneuvering means 4, to assist/guide the rotational maneuver of the lever 3 around its axis of rotation R, said lever 3 advantageously remaining in the same previously chosen plane.

Base

The base 2, illustrated in particular in FIGS. 1 to 5 or in the , here consists of a single piece.

The shape of this base 2 is in particular adapted according to the osteosynthesis plate P associated with it.

In general, the base 2 (advantageously in the form of a plate or plate) advantageously comprises two opposite faces:

- a rear face 21 adapted to be positioned against a surface of the bone S and/or against the osteosynthesis plate P, and

- A front face 22, opposite.

In this case, the rear face 21 advantageously comprises two portions ( ):

- a first support portion 211, intended to be positioned against the osteosynthesis plate P, and

- a second support portion 212, intended to be positioned against the surface of the bone S.

The base 2 further comprises assembly means 24, removable, with the osteosynthesis plate P, for the temporary fixation of the ancillary 1 on the osteosynthesis plate P (or even in one of the two bone fragments F1 or F2).

The assembly means 24 here comprise at least one through hole 241, 242 which is provided facing (otherwise said "which opens into the breast") of the first bearing portion 211.

A through hole 241, 242 is made to receive fastening means 243 (for example a screw - ) which can be temporarily implanted in a through hole P11, P21 of the osteosynthesis plate P.

A through hole 241, 242 of the base 2 is thus intended to come opposite a through hole P11, P21 of the osteosynthesis plate P, so as to be temporarily assembled by the fixing means 243.

In this case, the first support portion 211 covers each of the two parts P1, P2 (first and second) of the osteosynthesis plate P.

And the assembly means 24 comprise two through holes 241, 242:

- a first through hole 241 intended to come opposite a through hole P11 of the first part P1 of the osteosynthesis plate P, and

- a second through hole 242 intended to come opposite a through hole P21 of the second part P2 of the osteosynthesis plate P.

The through holes 241, 242 of the assembly means 24 open into the first support portion 211 of the base 2, each intended to come opposite one of the two bone fragments F1, F2.

The fixing means 243 can be removable with respect to the base 2 (see in particular the ).

Alternatively, as shown in the , the fixing means 243 are integrated / irremovable with respect to the through holes 241, 242 of the base 2.

In this case, the fixing screws 243 (for fixing the base 2 on the osteosynthesis plate P) are advantageously integrated into the base 2 in the form of trapped screws.

Alternatively, not shown, the fixing means 24 could consist of any other assembly means, for example elastic interlocking means (or clipping) for the removable connection between the base 2 and the osteosynthesis plate P.

The base 2 also comprises at least a first through hole 26, also called "lever through hole", which is intended to come opposite one of the two bone fragments F1, F2, here opposite the second bone fragment F2 (distal ).

The first through hole 26 is advantageously provided at the level of the second bearing portion 212 of the base 2.

This first through hole 26 is intended to be crossed by the lever 3.

This first through hole 26 advantageously comprises a bearing surface 261 cooperating with the lever 3, to participate in defining its axis of rotation R.

This support surface 261 here has the shape of a spherical, concave or female cap, the center of which is oriented towards the side of the front face 22 of the base 2.

The center of rotation R is advantageously as close as possible to the bone, in order to preserve bone correction.

Lever

The lever 3 is attached through this first through hole 26 of the base 2.

In general, the lever 3 comprises two sections ( ):

- a rear section 31 intended to extend from the side of the rear face 21 of the base 2 and to be inserted into one of the two bone fragments F1, F2, here the second bone fragment F2, and advantageously

- a front section 32 intended to extend from the side of the front face 22 of the base 2 and to cooperate with the maneuvering means 4 (for the rotational maneuver of the lever 3).

The lever 3 thus advantageously extends through the first through hole 26, on either side of the base 2.

The lever 3 and the first through hole 26 cooperate through assembly means 5 allowing at least one degree of freedom in rotation of this lever 3 around an axis of rotation R located at the level of the base 2.

By “at the level of the base 2”, is meant an axis of rotation R which is located within the thickness of the base 2 or opposite and close to its front face 22 (preferably less than 10 mm).

In general, the axis of rotation R is closest to the bone surface, a function in particular of the thickness of the plate P and of the base 2.

These assembly means 5 also form a fulcrum for the lever 3 (also called "inter-support lever").

In other words, this fulcrum is located between the two sections 31, 32 of the lever 3.

The fulcrum, formed by the assembly means 5, is located between:

- the front section 32 on which the force is intended to be applied, and

- the rear section 31 transmitting the force within the associated bone fragment F2.

Preferably, this axis of rotation R extends parallel to the general axis C' of the bone hinge C (see in particular ).

Preferably again, the assembly means 5 between the lever 3 and the first through hole 26 consist of an assembly forming a ball joint.

These assembly means 5 are presented for this here in the form of spherical bearing surfaces, complementary, which will be described in more detail later.

Such a technical characteristic thus confers a second degree of freedom in rotation for the lever 3 at the level of the assembly means 5, authorizing an angular adjustment of the axis of rotation R and of the lever 3 according to the general axis C ' of the bony hinge C (for example anterior, medial, or posterior).

In this case, lever 3 comprises an assembly of two parts:

- a lever rod 35 (visible isolated on the ), inserted through the first through hole 26 of the base 2 to form in particular the rear section 31 of the lever 3, and

- a lever guide 36, tubular, which is intended to receive this lever rod 35 and which here forms part of the assembly means 5 and/or part of the operating means 4.

The lever rod 35 here has a length greater than the length of the lever guide 36 to extend on either side of this lever guide 36 and of the base 2.

This lever rod 35 is thus intended to present:

- a free part 351, on the side of the rear face 21 of the base 2, forming the rear section 31 of the lever 3, and

- a guided part 352, on the side of the front face 22 of the base 2, housed within the lever guide 36 to together form the front section 32 of the lever 3.

The lever rod 35 has a mechanical resistance which allows it resistance to bending (in particular at the level of its free part 351) during the maneuver of the lever 3 allowing the compression of the bone hinge C.

The lever guide 36 advantageously takes the general form of a sleeve, a barrel or a cylinder.

As can be observed in particular in FIGS. 2 or 7, the lever guide 36 here has two longitudinal ends:

- a first end 36a, front, carrying a slider 361 forming part of the operating means 4 described in more detail later, and

- a second end 36b, rear, here presenting a support surface 362 having the shape of a spherical cap (convex or male) cooperating with the support surface 261 complementary to the first through hole 26 of the base 2.

These two ends 36a, 36b define the longitudinal axis 36' of the lever guide 36 ( ).

The lever guide 36 is here inserted between the slide 6 and the base 2, with said at least one degree of freedom in rotation R.

The slider 361 consists here of a sleeve comprising a through housing 3611 through which a slider 6 is here intended to be introduced and to slide.

This through housing 3611 extends perpendicular to the longitudinal axis 36' of the lever guide 36.

The bearing surface 362 of the lever guide 36 is intended to cooperate with the bearing surface 261 complementary to the first through hole 26 of the base 2, to together form the assembly means 5.

This lever guide 36 further includes a longitudinal through-hole 365 (also called a "duct"), opening out at the two ends 36a, 36b and advantageously coaxial with the aforementioned longitudinal axis 36' ( notably).

This longitudinal through hole 365 is designed to receive the lever rod 35, in particular its guided part 352.

The cross section of this longitudinal through hole 365 thus corresponds, except for play, to the cross section of the lever rod 35.

This dimensional characteristic ensures optimal guidance of the lever rod 35 during its introduction and its maneuver in rotation around the axis of rotation R.

Maneuvering means

The maneuvering means 4 intervene in the rotational maneuver of the lever 3 around its axis of rotation R (illustrated in particular in FIGS. 3 and 17).

These maneuvering means 4 here make it possible to apply a force to the front section 32 of the lever 3 (perpendicular and at a distance from the axis of rotation R) so as to apply a rotational movement to it around its axis of rotation R, advantageously in a given and fixed plane.

In general, the operating means 4 advantageously comprise:

- the slider 361 carried by the front section 32 of the lever 3, advantageously at a distance from the assembly means 5 and advantageously carried by the lever guide 36, and

- A slide 6 carried by the base 2, cooperating with the slider 361 for guiding it in translation.

Slide 6 defines a stroke 6' of slide 361 which has the shape of an arc of a circle whose center 6'' is crossed by the axis of rotation R of lever 3 ( ).

The slide 6 and the stroke 6' of the slide 361 are part of a general plane P which is oriented perpendicular to the axis of rotation R of the lever 3 ( ).

In other words, the lever 3 here pivots around the axis of rotation R which is perpendicular to the general plane passing through the slide 6 and through the assembly means 5 of the lever 3 / base 2 couple.

In other words, lever 3 is intended to pivot while remaining in this general plane P.

This slide 6 extends here opposite, and at a distance, from the front face 22 of the base 2.

This slide 6 here has an arcuate shape, the underside of which is oriented opposite the base 2.

As developed later, this slide 6 has two lights here:

- a transverse light 61 in an arc of a circle ( ), whose center 61' is crossed by the axis of rotation R of the lever 3, participating in the operating means 4 described later, and

- a front light 62 ( ), oriented perpendicular to the axis of rotation R of the lever, intended to be traversed by the front section 32 of the lever 3 (in particular by its lever rod 35).

The front slot 62 is intended to extend opposite the longitudinal through hole 365 of the lever guide 36 and in the aforementioned general plane P.

This front light 62 is thus useful for the introduction/extraction of the lever rod 35 with respect to the lever guide 36.

The slide 6 here has a rectangular section delimited by two pairs of opposite faces:

- two transverse faces 64, oriented here perpendicular to the axis of rotation R, and

- two end faces 65, oriented parallel to the axis of rotation R.

The transverse faces 64 are here traversed by the transverse slot 61; the front faces 65 are traversed by the front light 62.

The outer section (here rectangular) of the slide 6 corresponds, except for clearance, to the inner section (rectangular) of the through housing 3611 of the slider 361.

According to a particular embodiment which is illustrated , slider 361 cannot be removed from slider 6.

For this, the slide 6 here has two end stops:

- a first stop formed by an interlocking rod 67, and

- A second stop formed by a lug 68, here consisting of an irremovable screw.

The lug 68 is here carried by the end of an arm 69, connected to the slide 6 and extending opposite the fitting rod, the section of which allows an angular play to the lever guide 36 in order to facilitate its mounting on the base 2.

To control the operation of the slider 361 over the length of the slide 6, the maneuvering means 4 further comprise a system for maneuvering 41 of the slide 361 over the length of the slide 6.

This operating system 41 advantageously consists of a system of the pinion/rack type.

In this case, the slide 6 comprises a transverse slot 61 in an arc of a circle, the center 61' of which is crossed by the axis of rotation R ( ).

This transverse light 61 is in particular defined by a directrix, in an arc of a circle, which is centered on the axis of rotation R.

This transverse light 61 is delimited by two surfaces in an arc of a circle, at a distance and opposite, namely:

- a rear surface 611, convex, and

- a front surface 612, concave.

The transverse light 61, and in particular its front surface 612, is here provided with a rack 615.

The rack 615 is thus bent around the center 61' of the transverse slot 61.

This rack 615 advantageously comprises straight teeth, distributed over the length of the front surface 612.

For its part, the slider 361 carries a pinion 367, rotatable to ensure the path of the slider 361 along the slide 6 ( ).

This pinion 367 is thus intended to follow a trajectory corresponding to the stroke of the slider 6'.

The toothing of this pinion 367 is adapted to mesh with the toothing of the rack 615.

The axis of rotation of this pinion 367 is advantageously parallel to the axis of rotation R.

In this case, this pinion 367 is carried by a part called "compression actuator 368", mobile in rotation and carried here by the slider 361.

This compression actuator 368 (carrying the pinion 367 which cooperates with the rack 615 of the slide 6) is advantageously removable with respect to the slide 361.

Such a compression actuator 368 is interesting for improving the precision and the force in the operation of the slider 361 during the compression of the hinge.

The pinion 367 is intended to be housed in the through housing 3611 of the slider 6 so as to cooperate with the rack 615.

For this, the slider 361 here comprises a lateral notch 3612, emerging within the through-housing 3611 and extending parallel to the longitudinal axis 36' of the lever guide 36.

The compression actuator 368 comprises a cylindrical section 3681, forming a journal.

The lateral notch 3612 forms a smooth bearing, cooperating with the cylindrical section 3681, for the rotational guidance of the compression actuator 368.

The 368 compression actuator still has a 3682 head for its rotational operation.

This head 3682 here consists of a plate through which a hole passes for the introduction of a lever.

The compression actuator 368 thus comprises the pinion 367 and the head 3682, connected by the cylindrical section 3681.

In general, the slide 6 and the base 2 are still advantageously assembled by means of interlocking means 7.

The interlocking means 7 in question here comprise two elements:

- an interlocking rod 67, made in one piece with the slide 6, and

- at least one interlocking hole 27, blind, opening at the level of the front face 22 of the base 2.

A nesting orifice 27 here forms a sheath which is adapted to receive the nesting rod 67 by insertion in translation.

The interlocking rod 67 (male) and said at least one interlocking orifice 27 (female) are complementary to each other to allow assembly by interlocking.

In this case, the base 2 comprises several interlocking holes 27 juxtaposed, for example at least two and here three in number ( ).

Each interlocking orifice 27 thus allows a position of the slide 6 with respect to the base 2, in a different general plane P.

These interlocking holes 27 are advantageously distributed according to the different possible locations of the desired hinge (purely lateral positioning, more posterior or more anterior).

These interlocking holes 27 juxtaposed allow the surgeon to adapt the position of the slide 6 to the bone hinge C (for example anterior, medial, or posterior).

In combination with the assembly means 5 of the ball joint type, the different positions allow an angulation of the axis of rotation R around an adjustment axis of rotation A (advantageously perpendicular to the axis of rotation R) as illustrated on the .

Lever rotation locking means

In general, the ancillary 1 also advantageously comprises rotation locking means 8 of the lever 3 around the axis of rotation R.

Such rotation locking means 8 are here formed by a clamping screw 38 carried by the slider 361 and adapted to cooperate with the slider 6.

This clamping screw 38 comprises two parts:

- a threaded rod 381, cooperating with a threaded through hole 3618 provided in the slider 361 and intended to cooperate by friction with the slider 6, and

- A rotating operating head 382, formed here by two parallel fingers.

The clamping screw 38 further comprises a through hole 383, longitudinal.

This through hole 383 has a section identical to the section of the longitudinal through hole 365 of the lever guide 36.

The threaded through hole 3618 of the slider 361 is arranged coaxially with the longitudinal through hole 365 of the lever guide 36, so that the through hole 383 of the clamping screw 38 extends the longitudinal through hole 365 of the lever guide 36.

The threaded through hole 3618 of the slider 361 and the longitudinal through hole 365 of the lever guide 36 extend here on either side of the through housing 3611 of the slider 361.

The operation of the tightening screw 38 ensures the translation of its threaded rod 381 through the threaded through hole 3618 of the slider 361 between two positions:

- a retracted position relative to the through housing 3611 of the slider 361, freeing the translation of the slider 361 along the slider 6, and

- a deployed position within the through housing 3611 of the slider 361, so that the threaded rod 381 cooperates with the slider 6 (here by friction) and blocks the translation of the slider 361 along the slider 6.

The threaded rod 381, in the deployed position, here comes into contact with one of the two end faces 65 of the slide 6 (namely the end face 65 located opposite the base 2).

Equipment for bone surgery

In general, the ancillary 1 is advantageously part of a piece of equipment (or kit or assembly) for bone surgery, suitable for the implementation of an osteotomy technique.

Such equipment advantageously comprises:

- the ancillary 1 according to the invention,

- the osteosynthesis plate P, mentioned above,

- means 243 for the temporary fixation of the ancillary 1 on the osteosynthesis plate P, advantageously separate from the ancillary 1 or carried by the ancillary 1,

- a set of fixing screws V, intended to be inserted through the through holes P11, P21 of the osteosynthesis plate P and to be implanted in the bone fragments F1, F2,

- preferably an olive pin 50, intended to be positioned through one of the "free" through holes P21 of the distal part P2 of the osteosynthesis plate P and to be temporarily inserted into the opposite bone fragment ( ).

The olive pin 50 consists of a pin provided with an integrated ball 51, inserted along the length of the olive pin 50 (sections of pins extend on either side of the integrated ball 51).

The integrated ball 5 is intended to be positioned in one of the "free" through holes P21 of the distal part P2 of the osteosynthesis plate P; a rear section 52 of the olive pin 50 is intended to be inserted into the bone material.

This olive pin 50 prevents rotation of the second bone fragment F2 (distal) during compression (see ).

P process for an osteotomy technique

The implementation of the ancillary 1 according to the invention is described below in the context of a method for an osteotomy technique, in particular an osteotomy technique for opening the proximal tibia.

The process in question, described below in relation to FIGS. 9 to 15, comprises a succession of steps.

The method includes a step of cutting the bone, to form a bone hinge C connecting two bone fragments F1, F2.

Once the cut line is finished, the process continues with an osteotomy step, in this case in the form of a bone opening ( ).

The bone opening movement is performed by the operator. This opening movement is for example carried out by means of a wedge inserted between the two bone fragments F1 and F2 (or any other suitable instrument, such as a Mehari forceps).

In the event of breakage or weakening of the bone hinge C, the ancillary 1 according to the invention is implemented in combination with the osteosynthesis plate P.

For this, the method comprises a first step of partial fixation of the osteosynthesis plate P on a first bone fragment F1, for example the proximal fragment F1.

For this, the osteosynthesis plate P is suitably positioned against the bone S, taking into account in particular the expected correction.

The first partial fixation step then consists in inserting the fixation screws V through a first group of through holes P11 of the osteosynthesis plate P and so that they penetrate the first bone fragment F1.

In this case, the fixing screws V are here reported through the through holes P11 of the proximal part P1 of the osteosynthesis plate P and so that they penetrate into the proximal fragment F1.

The proximal part P1 of the osteosynthesis plate P is thus secured to the proximal fragment F1.

At least one of the through-holes P11 of the first group of through-holes P11 is here left free to attach the base 2 of the ancillary 1.

To be complete, the other part of the osteosynthesis plate P (here the distal part P2) is here free in relation to the second fragment F2 (here the distal fragment F2).

The method then comprises a step of temporarily attaching the base 2 of the ancillary 1 to the osteosynthesis plate P positioned on the bone S ( ).

The assembly means 24 are implemented for this: the fixing means 243 (for example screws, possibly trapped according to the ) are here implanted in the "free" through holes P11, P21 of the osteosynthesis plate P ( ).

The operator also reports, on base 2, the slide 6 / lever guide 36 pair (without the lever rod 35).

In this case, the slide 6 and the base 2 are still assembled by means of the interlocking means 7.

The interlocking means 7 in question here comprise the interlocking rod 67 of the slide 6 which is introduced into one of the interlocking orifices 27 complementary to the base 2.

At the same time, the lever guide 36 is assembled with two elements:

- its slider 361 is assembled with the slider 6, and

- Its support surface 362 is assembled with the support surface 261 complementary to the first through hole 26 of the base 2 to form the corresponding assembly means 5.

At the slider 361, the additional parts can be pre-mounted on the lever guide 36:

- the compression actuator 368 carrying the pinion 367 which cooperates with the rack 615 of the slide 6, and

- The tightening screw 38 of the rotation locking means 8 in the retracted position.

Alternatively, the compression actuator 368 (carrying the pinion 367 which cooperates with the rack 615 of the slide 6) is added at the moment of compression, after the positioning of the lever 3.

Before insertion of a rear section 31 of the lever 3 in one of the bone fragments F2, the olive pin 50 is advantageously positioned through one of the "free" through holes P21 of the distal part P2 of the plate of osteosynthesis P with its rear section 52 pressed into the second bone fragment F2 opposite, to prevent rotation of the second bone fragment F2 (distal) during compression (see the ).

Again before insertion of a rear section 31 of the lever 3 in one of the bone fragments F2, the lever guide 36 is advantageously pivoted so as to extend parallel, or at least approximately parallel, with respect to the free face of the second F2 bone fragment generated by the osteotomy cut line ( ).

If necessary, this movement of the lever guide 36 is ensured by an operation of the compression actuator 368 in a suitable direction of rotation. The movement of the lever guide 36 can also be implemented manually, before the positioning of the compression actuator 368.

The position of the lever guide 36 is then locked here using the tightening screw 38 of the rotation locking means 8, operated in the deployed position.

The second bone fragment F2 is then drilled with a drill which is guided by the guide lever 36 (locked in position).

After removal of the drill, the rear section 31 of the lever 3 is placed in the second bone fragment F2 (free in relation to the osteosynthesis plate P).

In this case, the lever rod 35 is inserted through the lever guide 36 (along the longitudinal through hole 365 of the lever guide 36) and through the second bone fragment F2 (figures 12 and 13).

The clamping screw 38 is loosened (in the retracted position) then the lever 3 is operated in rotation around its axis of rotation R so as to obtain a compression stage of the bone hinge C ( ).

The compression is in particular obtained by a maneuver of the rear section 31 of the lever 3 in a direction corresponding to the bringing together of its free end towards the bone hinge C.

In other words, the compression of the bone hinge C is obtained by the pushing force which is applied to the second bone fragment F2 (by the lever 3) in a direction oriented towards the first bone fragment F1 which is fixed by the osteosynthesis plate P.

This rotational maneuver is obtained here by the intervention on the compression actuator 368, added before or after the positioning of the lever rod 35.

For this, the compression actuator 368 is rotated in an appropriate direction, so as to cause the slider 361 to move along the slide 6 and in a direction suitable for putting the bone hinge C under compression.

When the desired compression has been obtained, the tightening screw 38 is tightened here to maintain the compression of the bone hinge C.

A second step of fixing the osteosynthesis plate P is implemented by inserting the fixing screws V through the second group of through holes P21 and so that they penetrate into the second bone fragment F2.

Lever rod 35 can then be extracted from bone S and ancillary 1.

The ancillary 1 is then removed from the osteosynthesis plate P which remains attached to the two bone fragments F1, F2 whose bone hinge C remains in compression ( ).

Implantation of the P osteosynthesis plate is finalized by following the associated surgical technique (conventional in itself), in particular by inserting the fixation screws V into the last free through holes of the P osteosynthesis plate.

At the end of this process, the osteosynthesis plate P is attached to the two bone fragments F1, F2 so as to maintain these two bone fragments and the compression of the bone hinge C.

This compression of the bone hinge C makes it possible to preserve the correction and facilitate consolidation.

Of course, various other modifications may be made to the invention within the scope of the appended claims.

Claims (15)

Instrument for bone surgery, intended to be attached to an osteosynthesis plate (P) positioned on the bone (S) of a patient, for the compression of a bone hinge (C) between two bone fragments (F1 , F2) during an osteotomy technique, in particular an opening osteotomy technique,
which ancillary includes:
(i) a base (2) comprising:
- a rear face (21) adapted to be positioned opposite a surface of said bone (S) and/or of said osteosynthesis plate (P),
- assembly means (24) with said osteosynthesis plate (P), and
- at least one first through hole (26), intended to come opposite one of said two bone fragments (F1, F2),
(ii) a lever (3), attached through said first through hole (26) of said base (2),
which lever (3) comprises a rear section (31) intended to extend from the side of said rear face (21) of the base (2) and to be inserted into one of the two bone fragments (F1, F2),
which lever (3) and which first through hole (26) cooperate via assembly means (5) allowing at least one degree of freedom in rotation of said lever (3) about an axis of rotation (R) located at the level of said base (2), advantageously extending parallel to the general axis (C') of the bone hinge (C), and
(iii) maneuvering means (4), for the rotational maneuvering of said lever (3) around said axis of rotation (R). Instrument for bone surgery, according to claim 1, characterized in that the lever (3) comprises:
- a lever rod (35), attached through said first through hole (26) of said base (2) and forming the rear section (31) of the lever (3), and
- a tubular lever guide (3), which is intended to receive said lever rod (35) and which forms part of the assembly means (5) and/or part of the operating means (4). Instrument for bone surgery, according to any one of claims 1 or 2, characterized in that the lever (3) comprises a front section (32), intended to extend from the side of a front face (22) of the said base (2), which cooperate with the operating means (4) for the rotational operation of said lever (3). Instrument for bone surgery, according to claim 3, characterized in that the operating means (4) comprise:
- a slider (361) carried by the front section (32) of the lever (3),
- a slide (6) carried by the base (2), cooperating with said slide (361) for guiding it in translation,
which slider (6) defines a stroke (6') of slider (361) which has the shape of an arc of a circle whose center (6'') is crossed by said axis of rotation (R). Instrument for bone surgery, according to claim 4, characterized in that the maneuvering means (4) comprise a system (41) for maneuvering the slide (361) along the length of the slide (6), advantageously a system of the pinion type / rack. Instrument for bone surgery, according to claim 5, characterized in that, in the presence of the rack and pinion type system, the slide (6) comprises a transverse slot (61) in an arc of a circle whose center (61') is crossed by the axis of rotation (R) and which is provided with the said rack (615), and in that the slider (361) carries the said pinion (367), movable in rotation to ensure the routing of the said slider (361) along of said slide (6). Instrument for bone surgery, according to any one of Claims 4 to 6, characterized in that the slide (6) includes a front slot (62), intended to be traversed by the front section (32) of the lever (3), and oriented perpendicular to the axis of rotation (R). Instrument for bone surgery, according to any one of claims 4 to 7, characterized in that the slide (6) is carried by the base (2), opposite and at a distance from a front face (22) of the said base (2). Instrument for bone surgery, according to claim 8, characterized in that the slide (6) and the base (2) are assembled by means of interlocking means (7). Instrument for bone surgery, according to any one of Claims 4 to 9, characterized in that the slide (6) and the base (2) cooperate by means of assembly means (7) allowing at least two positions of the said slide (6) relative to said base (2). Instrument for bone surgery, according to any one of Claims 1 to 10, characterized in that the assembly means (5) between the lever (3) and the first through-hole (26) consist of an assembly forming a ball joint. Ancillary for bone surgery, according to claim 11 in combination with claim 2, characterized in that the lever guide (3) comprises a first end (36a) carrying the slider (361) and a second end (36b) presenting a surface of support (362) in the form of a spherical cap cooperating with a bearing surface (261) of the first through hole (26) of the base (2). Ancillary for bone surgery, according to any one of claims 1 to 12, characterized in that it comprises means for locking in rotation (8) of said lever (3) around said axis of rotation (R). Instrument for bone surgery, according to any one of Claims 1 to 13, characterized in that the rear face (21) of the base (2) comprises a bearing portion (211) able to be positioned against the said base plate. osteosynthesis (P),
and in that said ancillary (1) comprises at least one through hole (241, 242) made facing said support portion (211), intended to receive fastening means (243) which can be temporarily implanted in a through hole ( P11, P21) of said osteosynthesis plate (P), for the temporary fixing of said ancillary (1) on said osteosynthesis plate (P) and even in said bone (S). Equipment for bone surgery, suitable for the implementation of an osteotomy technique, in particular an opening osteotomy technique, characterized in that said equipment comprises:
- an ancillary (1) according to any one of claims 1 to 14,
- an osteosynthesis plate (P) provided with two groups of through holes (P11, P12), one proximal and the other distal, each of said groups being intended to accommodate fixing screws (V) intended to be implanted in one of the two bone fragments (F1, F2),
- means (243) for the temporary fixing of said ancillary (1) on said osteosynthesis plate (P),
- a set of said fixing screws (V), intended to be inserted through the through holes (P11, P21) of said osteosynthesis plate (P) and to be implanted in the bone fragments (F1, F2), and
- preferably an olive pin (50), intended to be positioned in one of the through holes (P21) of the osteosynthesis plate (P) and to be temporarily inserted into the bone fragment (F2) opposite.