Device for correcting rotational malalignment syndrome

Abstract

The invention relates to a device for correction in the rotational plane of the axis of long bones during growth spurts, wherein the device comprises a fixing plate and a guide-stop to generate the relative rotation of bone zones where the plate and the guide-stop are respectively fixed. The invention also relates to a minimally invasive technique and positioning guide for the placement of said device.

Description

[0001] DEVICE FOR THE CORRECTION OF MALALIGNMENT SYNDROME

[0002] ROTATIONAL

[0003] STATE OF THE ART OF THE INVENTION

[0004] Field of Invention

[0005] The present invention relates to the field of medical devices and in particular refers to a fixation plate and guide stop device for generating relative rotation of bone areas where the plate and the guide stop are fixed respectively, preferably for correction in the rotational plane of the axis of long bones during the growth thrust thereof, as well as the invention relates to a minimally invasive technique for placing said device.

[0006] Description of prior art

[0007] In the field of orthopedics, particularly pediatric orthopedics, there is what is known as rotational malalignment syndrome of the lower limbs. This syndrome presents as a marked abnormality with exaggerated medial torsion at the level of the femur and excessive lateral rotation of the tibia. When the affected individual stands, their knees are turned inward and their feet are in maximum external rotation.

[0008] Alignment disorders can be constitutional, also called physiological, or pathological. In general, constitutional disorders occur in normal individuals, that is, with normal development, without signs of dysplasia, normal height, etc., and the deformity tends to be moderate, often bilateral and symmetrical. Imaging tests such as plain radiography (X-ray) or computed axial tomography (CT) do not detect any alterations other than the deformity itself. They have no known cause. They do not usually cause functional problems, but when severe, they produce aesthetic problems, gait disturbances, and mechanical imbalances that promote premature joint degeneration. Examples of these would be femoral antetorsion or genu valgum during development. Secondly, there are other alignment disorders caused by pathological causes, whether congenital or acquired.Any pathological osteoarticular process of traumatic, neoplastic, inflammatory, infectious, or degenerative origin can cause a lower limb deformity. Treatment for these deformities is twofold: specific to the underlying cause and the deformity itself.

[0009] Most children and adults walk with their feet rotated externally by an average of 10°. A gait with internal rotation greater than 10° or external rotation greater than 30° is considered pathological. These deformities usually originate in the femur or tibia and are diagnosed by the physician, thanks to their knowledge of the development of children's limbs, along with a thorough clinical evaluation, thus differentiating between what is common and what is pathological.

[0010] Rotational malalignment is a common problem in children. It often presents physiologically at an early age and often corrects as the child grows. In cases where the deformity is very marked or does not correct with age, the only clear immediate solution is osteotomy of the involved bone and derotation with internal fixation.

[0011] Derotation osteotomy surgery is a invasive procedure, with associated risks such as bleeding, nonunion, displacement, incomplete correction, or overcorrection, and risks associated with the implant used, such as implant breakage or failure, and associated infection. It also involves hospitalization, delayed weight-bearing, and costs to the healthcare system.

[0012] For deformities in other planes, particularly coronal but also sagittal, the use of guided growth devices has long been proven and well accepted. These devices utilize the child's remaining growth and modulate it to correct any existing abnormalities. The guided growth method proposed by Professor Dr. Peter Stevens (Plate 8) for the correction of angular defects in the frontal and sagittal planes has provided a minimally invasive solution without the need for bone cutting, with faster rehabilitation and the possibility of establishing a temporary procedure, allowing for the reversal of physeal braking, i.e., of the physis, once the desired correction is achieved.

[0013] The so-called long bones have at their end a zone called the epiphysis, which continues toward the center into another zone called the metaphysis, after which, continuing toward the center of the bone's length, is the body or diaphysis. Between the epiphysis E and the metaphysis M is the physis F, which is the growth cartilage. The growth cartilage is important for bone development.

[0014] Recent studies have suggested the possibility of using this concept to correct rotational deformities, i.e., axial plane deformities. If achieved, this could lead to a less invasive technique that avoids osteotomies and their associated complications.

[0015] In the last 10 years, the idea of ​​using guided growth in the axial plane for rotational correction of the immature skeleton has emerged.

[0016] The first author to begin investigating the potential use of a rotational growth-guided system was Arami, who in 2013 hypothesized that placing plates in an oblique position, with both epiphyseal and metaphyseal anchoring, would cause subsequent rotation. He developed a mathematical model and then tested it in rabbits using a rigid plate, achieving the desired angular correction and theorizing that this concept could be used in the future. It is worth noting that, associated with rotational correction, shortening occurs, which could be considered a complication.

[0017] Since that publication, two others have been published that study different aspects of this rotational guided growth generated with oblique rigid plates in rabbits. In 2016, Cobanoglu studied 45 rabbits, evaluating whether this method was able to generate rotation associated with the animals' growth. Meanwhile, in 2017, Lazarus et al. delved further into the study of this construct and evaluated the angle of plate placement and its relationship to the generated rotation.

[0018] Seeking to advance knowledge generation in this area, in 2018 Martel expanded to studies in large animals, particularly calves, and proposed a different method for generating rotation: a construct with two cannulated screws, one metaphyseal and one epiphyseal, and a circular wire passing through both and placed at opposite angles in the lateral and medial sectors of the distal femur. He thus presents results that clearly demonstrate the generation of rotation associated with the growth of the animals, with consistent alignment of the placed screws.

[0019] More recently, and based on the previously mentioned studies, two human studies have been conducted.

[0020] In 2019, Metaizeau published a series of cases using a construct similar to Martel's in the distal femur of 20 knees, showing very good correction and proposing it as a possible valid alternative to derotation osteotomies. In the most recent study, from 2023, Paley published a series of cases using an implant with a principle similar to oblique plates but with less rigidity due to having an intermediate sector with very high-resistance tapes that use a long-chain polyethylene structure, known by the trademark Fibertape. He performs surgeries to correct both intrarotation and extrarotation, and in both the tibia and femur, also publishing encouraging results.

[0021] The system proposed by Paley in this analyzed study uses the two male hemiplates of the hinge plate system developed by the Pegamedical firm, fixed with a screw, one to the metaphyseal sector and the other to the epiphyseal sector, joined with “Fibertape” suture from the Artrhex firm at 45° angulation in the internal sector and another in the external sector of the bone. See EFORT Open Reviews (2024) 9 119-128 https: / / doi.orq / 10.1530 / EQR-23-0149, GENERAL ORTHOPAEDICS, “Correction of rotational deformities in long bones using guided growth: a scoping review” Ahmed Halloum 1 , Soren Koldl , Jan Duedal Rolfing 2, Ahmed A Aboodl ,2 and Ole Rahbekl .

[0022] All the systems analyzed so far to generate rotational correction during bone growth, i.e., rotational guided growth, propose a construct with an epiphyseal and metaphyseal anchorage, so that after achieving the desired correction, it must be removed to avoid generating physeal braking.

[0023] More specifically, to induce corrective rotation, i.e., rotation between the bone and the epiphyseal plate, plates, bars, or wires are attached, with one end attached to the plate and the other end attached to the metaphysis. These bars are extended diagonally, so that as the bone grows, the diagonal plate or wire causes the bone to rotate relative to the epiphysis. However, once rotational correction has been achieved, the anchor, whether a plate, wire, etc., must be removed to prevent it from slowing axial growth of the bone, i.e., from impeding growth of the metaphysis.

[0024] The surgical techniques used in these studies are not analyzed in detail or present difficult steps for the correct positioning of the proposed constructs, although these placement techniques are essential for the correct functioning of these studied systems.

[0025] Although these new techniques are promising, their effectiveness still needs to be improved to avoid requiring further surgery to untie and remove the element causing the rotation, in the best of cases, just before it begins to act as a growth restraint.

[0026] BRIEF DESCRIPTION OF THE INVENTION

[0027] It is therefore an object of the present invention to provide a new anchor plate system for rotational correction between bone and epiphysis that functions freely without the risk of causing growth retardation once the syndrome to be treated has been corrected, or partially corrected.

[0028] Another object of the present invention is to provide a rotational correction plate system that does not generate physeal braking during guided growth nor necessarily requires a second surgery to release the system, or if it is necessary to continue correcting in the rotational plane it can continue acting with small surgical gestures.

[0029] Another object of the present invention is to provide a plate with epiphyseal anchorage and metaphyseal extension that has at least one hole at the epiphyseal level to generate a bone anchorage which can be with a cannulated or non-cannulated locked screw.

[0030] Another object of the present invention is to provide a plate with epiphyseal anchorage and metaphyseal extension that has at least one hole at the epiphyseal level to generate a bone anchorage which can be with a cannulated or non-cannulated non-locking screw.

[0031] Another object of the present invention is to provide a plate with epiphyseal anchorage and metaphyseal extension that has at least one hole at the epiphyseal level to generate a bone anchorage which can be with a double locking head for Kirschner that allows joining with the contralateral symmetrical plate hole.

[0032] Another object of the present invention is to provide a plate with epiphyseal fastening and metaphyseal extension where the metaphyseal extension generates a fixed angle with the physis, which can be variable at the time of manufacture, preferably being 60°.

[0033] Another object of the present invention is to provide a plate with an epiphyseal fastening and a metaphyseal extension where the metaphyseal extension generates a fixed angle with the physis, which can be variable at the time of manufacture and allows sliding relative to a metaphyseal stop that is placed.

[0034] Another object of the present invention is to provide a plate with an epiphyseal anchor and a metaphyseal extension where the metaphyseal extension generates a fixed angle with the physis, which can be variable at the time of its manufacture where said metaphyseal extension can be solid manufactured or can have a complete or incomplete central groove to accommodate a metaphyseal stop that is placed allowing its sliding.

[0035] Another object of the present invention is to provide a plate with epiphyseal anchorage and metaphyseal extension where the metaphyseal extension generates a fixed angle with the physis, which can be variable at the time of its manufacture. Said plate can be made of titanium, surgical steel or any other biocompatible material which can also be resorbable.

[0036] Another object of the present invention is to provide a bicortical metaphyseal element, which may be a screw or a bar that allows generating a stop on the plate or plates that are placed, for which it must protrude from one or both cortices respectively.

[0037] Another object of the present invention is to provide a bicortical metaphyseal element, which can be a screw or a bar that allows generating a stop in the plate or plates that are placed, it can be developed in titanium, surgical steel or any other biocompatible material, even in bioabsorbable material.

[0038] Another object of the present invention is to provide a bicortical metaphyseal element, which may be a cannulated or non-cannulated screw, with a full or partial thread, with a self-tapping, self-drilling or blunt tip, which allows generating a stop on the plate or plates that are placed, for which it must protrude from one or both cortices respectively. This element may be associated with a threaded or non-threaded washer on each side of the screw to allow a lateral stop and prevent the system from coming loose as well as cover the tip of the screw, avoiding injury to the soft tissues or discomfort to the patient.

[0039] Another object of the present invention is to provide a bicortical metaphyseal element, a cannulated or non-cannulated bar, with partial or complete thread, with blunt tips and at the tips it can be shaped like an alien key and can be placed or removed from either side, which allows generating a stop on the plate or plates that are placed, for which it must protrude from one or both cortices respectively. Another object of the present invention is to provide a mono or bicortical metaphyseal element, which can be a screw or similar that allows generating a stop on the ipsilateral plate, for which it must protrude from said cortex and two of these components must necessarily be placed if a double plate is used.

[0040] Another object of the present invention is to provide a mono or bicortical metaphyseal element, which may be a screw or similar that allows generating a stop on the ipsilateral plate, for which it must protrude from said cortex and two of these components must necessarily be placed if a double plate is used, made of titanium, surgical steel or any biocompatible element, whether resorbable or not.

[0041] Another object of the present invention is to provide a metaphyseal anchoring element that allows generating a stop in the metaphyseal extension of the ipsilateral plate. To do this, it must protrude from said cortex, and two of these components must necessarily be placed if a double plate is used. These can be tubular systems of different morphologies that allow the metaphyseal extension of the plates and are fixed to the bone in different ways.

[0042] Another object of the present invention is to provide a metaphyseal anchoring element that allows for the generation of a stop in the metaphyseal extension of the ipsilateral plate. To do this, it must protrude from said cortex, and two of these components must necessarily be placed if a double plate is used. These can be staples of different morphologies that allow for the metaphyseal extension of the plates and are fixed to the bone in different ways.

[0043] Another object of the present invention is to provide a metaphyseal anchoring element that allows generating a stop in the metaphyseal extension of the ipsilateral plate, for which it must protrude from said cortex and necessarily two of these components must be placed if a double plate is used. They can be tubular systems of different morphologies that admit the metaphyseal extension of the plates and are fixed to the bone in different ways or staple-type systems, they can be made of titanium, surgical steel or any biocompatible material, resorbable or not.

[0044] Another object of the present invention is to provide a metaphyseal anchoring element, which allows generating a stop in the metaphyseal extension of the plates, consisting of a cannulated screw that protrudes from both cortices which is then threaded by a cerclage wire or cable that embraces the metaphyseal extension of the plate that is in contact with the tip of the screw and this cerclage is fixed to the head of the screw.

[0045] Another object of the present invention is to provide a metaphyseal anchoring element, which allows generating a stop in the metaphyseal extension of the plates, consisting of a cannulated screw that protrudes from both cortices which is then threaded by a cerclage wire or cable that embraces the metaphyseal extensions of the plates and this cerclage is fixed to the head of the screw.

[0046] It is an object of the present invention to provide a device for correcting rotational malalignment syndrome in an individual suffering from the syndrome, wherein the device comprises at least one fixation plate having a first clamping end portion having fixation means for being fixed to a first area of ​​a bone, and a second free end portion designed to extend over a second area of ​​the bone without fixation thereto, at least one guide stop designed to be fixed to said second area of ​​the bone, and at least one guide edge on said second free end portion for bearing in a guided manner against said guide stop.

[0047] It is yet another object of the present invention to provide a positioning guide for the installation of the device of the invention, comprising an internal part and an external part, movable relative to each other in approaching and moving away, wherein each of the internal and external parts has a sector designed to accommodate the shape of the fixing plate of the invention, said sector presenting two cylinders for threading installation wires, said sectors being fixed to respective arms which in turn are joined to telescopic coupling arms between them.

[0048] It is another object of the present invention to provide a method of placing the aforementioned positioning guide, comprising the steps of:

[0049] Step 1: Thread, through one of the cylinders on the inner and outer parts of the guide respectively, a metaphyseal Kirschner wire previously positioned in the bone;

[0050] Step 2: Assemble the telescopically coupled arms;

[0051] Step 3: Position the placement guide on the profile, using the image intensifier to place one of the cylinders, which is a radiopaque hollow epiphyseal cylinder, in the center of the epiphysis, allowing the epiphyseal Kirschner wire to be placed in its correct position, and then remove the guide.

[0052] It is another object of the present invention to provide a method of installing the device of the invention, comprising the following steps:

[0053] Step 1: Place a metaphyseal Kirschner wire parallel to the E physis at the front of the bone, for example 1 cm at the metaphyseal level and in the center of the bone in the profile, looking for the correct positioning with the image intensifier;

[0054] Step 2: Assemble the placement guide on the Kirschner wire, through the cylinder, which allows locating the correct positioning of the epiphyseal Kirschner wire;

[0055] Step 3: Place an epiphyseal Kirschner wire through the guide and remove it;

[0056] Step 4: Ream with a cannulated drill through the metaphyseal wire and place a bicortical cannulated screw, from the side that is in front of the plate, so that at the time of rotation it is positioned anterior and its removal is facilitated, positioning the bicortical screw so that it protrudes half a centimeter on each side of the bone, to generate the metaphyseal guide stop; Step 5: perform a 3 cm epiphyseal approach, internal and external, centered on the Kirschner wire for the correct sliding of the epiphyseal plate, sliding the plate achieving contact with the second extreme portion or metaphyseal extension, with the guide stop already installed, being able to facilitate the sliding of the plate by placing a threaded guide sleeve in the central locking hole and in this way use it as a handle;

[0057] Step 6: Remove the epiphyseal Kirschner wire, position the plate with the centralizing hole where the Kirschner wire was and drill through the locking sleeve, placing the locked centralizing screw through the plate, then placing the second locked screw on each side, closing in layers by performing a correct washing and hemostasis and controlling the final positioning of the device with an image intensifier.

[0058] BRIEF DESCRIPTION OF THE DRAWINGS

[0059] For greater clarity and understanding of the object of the present invention, it has been illustrated in several figures, in which the invention has been represented in one of the preferred embodiments, all by way of example, where:

[0060] Figure 1 is a sagittal view of a left distal femur in which a plate has been implanted according to an embodiment of the present invention;

[0061] Figure 2 is a sagittal view of a left distal femur in which two plates, one internal and one external, have been implanted in accordance with another embodiment of the present invention;

[0062] Figure 3 is an axial view of a left distal femur in which two plates, one internal and one external, have been implanted in accordance with the invention;

[0063] Figure 4 is a sagittal view of a distal left femur, with internal and external mirror plates to generate external rotation of the distal femur; Figure 5 shows a sagittal view of a left proximal tibia with a plate according to another embodiment of the invention;

[0064] Figure 6 shows a sagittal view of a left proximal tibia with a double plate according to another embodiment of the invention;

[0065] Figure 7 is a sagittal view of a distal left femur, with a plate according to another embodiment of the invention;

[0066] Figure 8 is a sagittal view of a distal left femur, with a plate according to another embodiment of the invention;

[0067] Figure 9 shows a view of two plates in combination with a cannulated screw, according to another embodiment of the invention;

[0068] Figure 10 shows a view of two plates in combination with a bicortical bar, according to another embodiment of the invention;

[0069] Figure 11 shows a view of two plates in combination with two screws as a metaphyseal stop, according to another embodiment of the invention;

[0070] Figure 12 shows a view of two plates in combination with two staples as a metaphyseal stop, according to another embodiment of the invention;

[0071] Figure 13 shows a view of two plates in combination with two sleeves as metaphyseal stops, according to another embodiment of the invention;

[0072] Figure 14 shows a perspective view of a positioning guide used in the implant technique according to another embodiment of the invention, and

[0073] Figure 15 shows a sagittal view of a section of the epiphyseal anchor plate for distal femur according to another embodiment of the invention.

[0074] DETAILED DESCRIPTION OF THE INVENTION

[0075] Referring now to the figures, it can be seen that the invention consists of a new device for the rotational correction of bone malformations. As can be seen in Figure 1 , according to a sagittal view of a left distal femur, generally indicated with the reference F and presenting an area E which is the epiphysis, and an area M which is the metaphysis, both areas already explained above. It is important to clarify that even when a femur is illustrated, the invention is applicable to the correction of any human or animal bone with a rotational disorder.

[0076] The device, indicated by the general reference 1, according to an embodiment of the invention, comprises a plate 1.a of generally angled, preferably curved shape, having a first end portion 1.e for anchoring intended to be fixed in at least one of the bone zones E or M, and a second free end portion 1.f, or metaphyseal portion, intended to be free, that is to say not fixed to the other zone E or M of the bone F. According to the terminology used in this description, if the first end portion 1.e is intended to be anchored or fixed in the epiphysis, it can be called an epiphyseal anchoring portion, and if the second end portion 1.f is intended to remain free on the metaphysis, it can also be called a metaphyseal extension.

[0077] The device 1 further comprises a guide stop 1.d which is fixed to the bone zone E or M where the end 1.e of the plate 1.a is not fixed. That is to say, if the plate is fixed in zone E or epiphysis, defining the aforementioned epiphyseal anchor, the guide stop 1.d is fixed in zone M or metaphysis and its purpose is to define a guide support for the plate 1.a along an edge 1.g of the plate.

[0078] The plate 1.a has at least one hole 1.b in its first end portion 1.e intended to receive a fixing screw, not illustrated because any such screw is well known in the art. If a single screw is used in the hole 1.b, the type of screw and fixing must ensure that the plate 1.a is fixed against rotation.

[0079] Alternatively, plate 1.a may include a second hole 1.c, to receive a second fixation screw, which is also not illustrated because it is of any type known in the art. Hole 1.c may be completely closed or open, as illustrated, because the object is that the screw placed in hole 1.c is not to fix plate 1.a against the bone, which is already done by the screw applied in hole 1.b, but its function is to prevent rotation, to the left, as seen in the figure, of plate 1.a, as will be explained below. For this same reason, hole 1.c may simply be a slot or recess in the plate or even none of these forms are necessary in the profile of the plate.

[0080] As is well known, bone growth originates in the physis, so over time, the metaphysis extends axially away from the epiphysis. According to the invention, this extension of the bone is used to generate a guided relative rotation between the epiphysis, the physis, and the metaphysis in the desired direction, intended to correct misalignment of, for example, the lower limbs of an individual, generally a child or adolescent in their growth stage.

[0081] That is, the device of the invention generates said rotation by taking advantage of the extension, growth, of the bone. With the first end portion 1.e fixed to the epiphysis E and with the guide stop 1.d fixed to the metaphysis M, as bone is generated away from the epiphysis, the guide stop 1.d moves axially away from the first end portion 1.e of the plate 1.a, which is fixed to the epiphysis E and prevented from rotating. Faced with this impediment to rotation, the guide stop 1.d rests against the edge 1.g of the plate and as it moves axially away from the hole 1.b it moves rotationally to the right in the direction of Figure 1. The edge 1.g, by forming an angle with the first extreme portion 1.e, forces the rotational movement of the guide stop to the right of the figure and thus forces the metaphysis to rotate with respect to the epiphysis.

[0082] There is thus a torsional effect between the epiphysis and the metaphysis, which generates relative rotation between the two. The support between the guide stop and the fixation plate does not maintain any fixation between them, which represents an impediment, block, or brake on the axial distraction of the parts. In the worst-case scenario, foreseeable and calculable, of course, the guide stop will have shifted axially so much that it will have exceeded the length of the extreme portion 1.f, leaving it out of contact with the guiding edge 1.g of plate 1.a. In this way, the individual's congenital misalignment is corrected. Through periodic imaging controls, the correction is monitored, for example, to determine when it should be stopped.

[0083] Unlike known techniques that fix plates or wires diagonally in the epiphysis and metaphysis, the present device is fixed in only one of them, and the enormous advantage is the following. When a growth point is reached, that is, a point of separation between E and M, a traditional plate or wire that had been fixed diagonally in the two zones E and F, due to the aforementioned separation, is arranged, due to the rotation generated between E and M, in an axially aligned form. It is at this point where it begins to function as a retainer or impediment to further extension or growth of the bone, and surgery must be performed to remove the plates or wire.

[0084] Unlike the previous one, plate 1.a forces the relative rotation between E and M but, since it is not fixed on the other side, in this case M, it allows growth without any limitation. This concept explained in relation to the embodiment of the device in Figure 1 is extensive to all the remaining embodiments illustrated in Figures 2 to 13. In the different embodiments, the shapes of the plates and their fastening or fixation vary, as well as the shapes of the guide stops and their fixation. The epiphyseal sector or first fastening portion 1.e of the plate can preferably use screws of the type known as locked screws. The epiphyseal anchorage in 1.b of these plates can be with one or more screws, preferably two screws, preferably locked or non-locking screws, cannulated or not.

[0085] In summary, the device 1 of the invention generates an internal rotational effect of the distal femur during physeal growth and the guide stop with the metaphyseal screw or bar (1.d) does not prevent axial extension of the bone. The advantage of this system is that, since it does not have a metaphyseal anchor but rather a guide stop that slides against the plate when moved axially, it can generate a rotational correction of the bone without causing physeal braking.

[0086] The fixation of the epiphyseal anchor, that is to say the first extreme portion 1.e of the plate, can be determined by locked or non-locked screws, not illustrated because they are conventional, as well as by any other form of anchorage that determines an epiphyseal fixation and leaves the metaphyseal prolongation or second extreme portion 1.f of the plate free.

[0087] In a preferred form of use of the plate of the invention, the corrective device, to work more effectively, comprises a double plate combination, that is, an internal and an external plate, of the femur, as will be seen in the following Figures in dashed lines.

[0088] As seen in Figure 2, the plate shown in solid lines is located on this side of the bone while the plate shown in dashed lines is located on the opposite side. This convention in the illustration of the plates is repeated in the rest of the figures that illustrate the use of two plates. When two plates are used, one on each side of the femur, the metaphyseal extension or second end portion 1.f of the plates is arranged in opposite directions, see Figure 2 as an example, and have the same angle of inclination with respect to the epiphysis E and physis Fi, which can be variable, for example 60° inclined with respect to physis Fi. This metaphyseal extension or second end portion 1.f can be solid or have a central slit open towards the free end or closed which can house the guide stop, as will be seen in embodiments described later.

[0089] Figure 2 shows a sagittal view of a left distal femur, to which the device of the present invention is fixed, which, according to this embodiment, comprises a double plate, that is, an internal plate 2.a and an external plate 2.e, which are symmetrical and can share the most central anchoring hole 2.b or not if it is desired to be fixed with a passing Kirschner locked on both sides in the plate with a double locking screw, all these components, wires, screws, used in the art. The guide stop of the invention can be a bicortical screw or bar 2.d that must protrude on both sides of the bone to generate the desired stop on the plates and the rotary sliding effect. Although in this Figure the reference numbers begin with 2, the parts of the plates are the same and equivalent to those of Figure 1. The reference numbers in the following figures will begin with the number of the corresponding figure.

[0090] Both the medial and lateral plates can be joined with a symmetrical epiphyseal anchor using a locked KW with a double-locking head. Depending on the direction of the metaphyseal extension or end portion 2.f of the medial and lateral plates, the effect of the metaphyseal stop will generate internal or external rotation of the bone.

[0091] Figure 3 shows an axial view of a left femur with the internal plate 3.a and the external plate 3.a', similar or equal to those in Figures 1 and 2, where the guide stop comprises a metaphyseal bar or screw 3.d that protrudes on each side of the cortex to define at its ends the guide stops on which they allow the sliding of the plates and generate the rotary effect on the plates.

[0092] Figure 4 also shows a sagittal view of a distal left femur, with plates 4.a internal and 4.a' external, arranged in mirror to generate with physeal growth and the metaphyseal guide stop 4.d an external rotation of the distal femur.

[0093] The guide stop, preferably fixed to the metaphysis, may comprise a bicortical screw or bar, parallel to the physis, which protrudes from the medial and lateral part of the cortex in order to stop the extreme portions or metaphyseal extensions of both plates and which, with physeal growth, moves away from the physis.

[0094] The design of the plates can vary, as can their mirror arrangement for the distal femur, depending on whether the arrangement is to be on the right or left femur and also whether the desired effect will be an external rotation of the bone or internal rotation during physeal growth.

[0095] According to another embodiment of the invention, Figure 5 illustrates a sagittal view of a left proximal tibia T with a plate 5.a having a “7” shaped design and wherein its epiphyseal anchoring portion includes two holes 5.c and 5.d intended to receive screws and be fixed taking into account the same considerations with respect to the previous embodiments of Figures 1 to 4, when the device of the invention for femoral use was described.

[0096] Figure 6 illustrates two plates like those in Figure 5, internal plates

[0097] 6.ay external 6.a' also fixed in a left proximal tibia to generate an internal rotation with the guide stop 6.d fixed in the metaphysis, with the same considerations as the previous embodiments developed for the distal femur.

[0098] For the proximal tibia, the figure-7 plate design is mirror-mounted depending on whether the tibia is right or left and whether the desired effect is external or internal rotation of the bone during physeal growth.

[0099] In accordance with yet another embodiment of the invention, Figure 7 illustrates a plate

[0100] 7.a with its epiphyseal anchoring portion and its metaphyseal extension, installed in a femur, where the metaphyseal extension has a central groove or slit 7.g open in its distal sector to accommodate and guide the guide stop 7.d.

[0101] In accordance with yet another embodiment of the invention, Figure 8 illustrates a plate

[0102] 8.a with its epiphyseal anchoring portion and its metaphyseal extension, installed in a femur, where the metaphyseal extension has a central groove or slit 8.g closed in its distal sector to accommodate and guide the guide stop 8.d.

[0103] These central grooves 7.g and 8.g form, with at least one of their inner edges, the equivalent of the guiding edge 1.g and 13.g and 15.g of the embodiments of Figures 1 to 13 and 15.

[0104] A preferred form of the guide stop is illustrated in Figure 9, which in this case comprises a simple cannulated screw 9.d which, by protruding from both sides of the cortex, defines, on each side, the guide stop itself on which the edges of the plates will rest to be guided axially and rotationally. This screw can admit two threaded washers 9.h to generate a lateral stop of the plate and prevent the system from coming loose and also to not leave the end of the screw free, which may cause soft tissue injury or discomfort. According to another embodiment, Figure 10 shows that the guide stop is formed by a bicortical bar 10.d that at both ends has a faceted shape 10.i, for example of the "Alien" key type, so that it can be removed from either end when it is required to loosen or remove the device of the invention.

[0105] According to another embodiment, Figure 11 shows that the guide stop is formed by two screws 11.d, independent of each other on each side of the bone.

[0106] According to another embodiment, Figure 12 shows that the guide stop is formed by a clip 12.d inside which the second end portion 12.f extends and slides to allow free axial extension and cause the desired rotation.

[0107] According to yet another embodiment, Figure 13 shows that the guide stop is formed by a sleeve or pocket 13.d inside which the second end portion 13.f extends and slides to allow free axial extension and cause the desired rotation.

[0108] Another embodiment of the invention is illustrated in Figure 15 and shows a sagittal view of the end of a long bone to which the device of the invention is fixed. In this alternative, the fixation plate comprises the two portions seen in the rest of the figures, a first anchoring end portion 15.e and a second free end portion 15.f. The improvement provided in this embodiment is that the end portions 14.e and 15.f are joined together through a hinge having hinge end portions 15.j and a central hinge portion 15.m. Preferably, parts 15.j are integral with the first tie end portion 15.e and the central hinge portion 15.m is integral with the second free end portion 15.f, however these parts could be reversed so that parts 15.j are integral with the second end portion 15.f and the central hinge portion 15.m is integral with the first tie end portion 15.e. This construction allows mobility in the frontal plane of said second extreme portion or free extension 15.f, which determines that it adapts to the metaphyseal diameter that accompanies it during the rotary growth effect, preventing it from being a blocking element thereof. When installed, once portions 15.e and 15.f are arranged in their desired position, parts 15.j and 15.m of the hinge are locked or fixed in position either by pressure, or by friction, or internal teeth of parts 15.j and 15.m which can be tightened by an internal screw 15. k.

[0109] It is important to highlight that even though the plates have been illustrated with their epiphyseal anchor or first end portion 1.e fixed to the epiphysis and the metaphyseal extension or second end portion 1.f of the plate fixed to the metaphysis, this assembly could be inverted, that is to say the first end portion 1.e could be fixed to the metaphysis and the second end portion 1.f could be fixed to the epiphysis if the anatomy of the bone allows it. Even though some discomfort may occur at the time of removing the device, this inverted placement is possible and is contemplated within the scope of the invention.

[0110] Also in accordance with the invention there is provided a positioning / placement guide which is illustrated in Figure 14 and which comprises an internal part 14.a and an external part 14.b. The internal part consists of a sector 14.a.1 designed to accommodate the plate shape, which has two cylinders for threading the Kirschner wires, one radiopaque represented in the centralizing hole of the first end portion, for example portion 1.e of Figure 1, or epiphyseal hole, of plate 14.a.2 and the other cylinder 14.a.3 where the second end portion 1.fo metaphyseal extension of the plate begins. This section of the inner part of the guide 14.a.1 which has the morphology of a plate, is continued by a suitably shaped arm, preferably rectangular 14. a.4, which is continued by an arm also rectangular 14. a.5 which will be coupled telescopically, or in another way, to the hollow horizontal arm 14.b.5 of the outer part 14.b of the guide.The external part of the guide also consists of a sector 14. b.1 designed to accommodate the plate shape, which has two cylinders for threading the Kirschner wires, one radiopaque represented in the centralizing hole of the first extreme portion 1.e, or epiphyseal hole, of the plate 14. b.2 and the other cylinder 14. b.3 where the second extreme portion begins, for example portion 1.f of Figure 1 , or metaphyseal extension of the plate. This sector of the internal part of the guide 14. b.1 that presents the morphology of the plate, is continued with an arm of convenient shape, preferably rectangular, 14. b.4, which is continued with arm 14. b.5 of the internal part of the guide after the metaphyseal Kirschner is threaded through the two cylinders of the guide, internal cylinder and external cylinder.

[0111] The placement guide in Figure 14 has been developed to carry out a surgical implant technique, also in accordance with the invention, for the correct position of both plates of the device, for example the plates in Figures 1 to 13, and their correct operation with the metaphyseal guide stop.

[0112] Preferred surgical implant method

[0113] The preferred method or technique, according to the invention, for implanting the device of the invention, consists of the following steps:

[0114] Step 1: A metaphyseal Kirschner wire is placed parallel to the E physis in front of the bone, for example 1 cm at the M metaphyseal level and in the center of the bone in the profile, looking for the correct positioning with the image intensifier.

[0115] Step 2: The placement guide is assembled on the Kirschner wire, through cylinder 14. a.2, which allows the correct positioning of the epiphyseal Kirschner wire to be located.

[0116] Step 3: An epiphyseal Kirschner wire is placed through the guide and the guide is removed.

[0117] Step 4: A cannulated drill is used to drill through the metaphyseal wire, and a bicortical cannulated screw is placed. This screw is inserted from the side anterior to the plate so that it faces anteriorly upon rotation and is easy to remove. This bicortical screw is positioned so that it protrudes half a centimeter on each side of the bone, creating the metaphyseal guide stop, for example, 1.d in Figure 1, or the stop in the other embodiments.

[0118] Step 5: A 3 cm internal and external epiphyseal approach is performed, centered on the Kirschner wire for the correct sliding of the epiphyseal plate, for example plate 1.a, the plate is slid until it comes into contact with the second extreme portion 1.f, or metaphyseal extension, with the guide stop already installed.

[0119] To facilitate the sliding of the plate, a threaded guide sleeve can be placed in the central locking hole and thus used as a handle.

[0120] Step 6: The epiphyseal Kirschner wire is removed, the plate is positioned with the centering hole 1.b where the Kirschner wire was and reamed through the locking sleeve, placing the locked centering screw through plate 1.a, then the second locked screw is placed on each side. The procedure is closed in layers, thoroughly washing and hemostasising the device, and the final positioning of the device is monitored with an image intensifier.

[0121] Guide placement method

[0122] Also according to the invention, the method or technique of using the positioning or placement guide comprises the following steps:

[0123] Step 1: Thread the hollow metaphyseal cylinder 14. a.3 and 14. b.3 from the inner and outer part of the guide 14 to the metaphyseal Kirschner wire that is positioned in the bone.

[0124] Step 2: Assemble the internal horizontal extensions 14. a.5, solid rectangular, and external 14. b.5 hollow rectangular, of the guide.

[0125] Step 3: Position the placement guide on the profile, using the image intensifier to place the radiopaque epiphyseal hollow cylinder 14. a.2 and 14. b.2 in the center of the epiphysis, this allows the epiphyseal Kirschner wire to be placed in its correct position, then remove the guide.

[0126] The placement guide allows determining the distance and orientation of the epiphyseal Kirschner wire placement.

Claims

CLAIMS 1. Device for correcting rotational malalignment syndrome in an individual suffering from the syndrome, wherein the device comprises: at least one fixation plate (1.a) having a first end portion (1.e) for fastening having fixation means (1.b-1.c) for being fixed to a first zone (E, M) of a bone, and a second free end portion (1.f) designed to extend over a second zone (E, M) of the bone, at least one guide stop (1.d) designed to be fixed in said second zone (EM) of the bone, and at least one guide edge (1.g) in said second free end portion (1.f) for bearing in a guided manner against said guide stop (1.g).

2. A device according to claim 1, wherein said fixing plate fixing means comprise at least one hole designed to receive a screw.

3. A device according to claim 2, wherein said fixing means comprise two holes.

4. A device according to claim 2, wherein said fixing means comprise at least said one hole and a cavity in an edge of said plate opposite said at least one guiding edge.

5. A device according to any of the preceding claims, wherein said plate is curved.

6. A device according to any one of claims 1 to 4, wherein said first and second end portions of the plate form an angle between each other of between 30 and 70 degrees.

7. A device according to any of the preceding claims, wherein said plate and said guide stop are made of a material selected from the group comprising stainless steel, titanium, plastic, polymer, surgical steel, metal, biocompatible material and resorbable material.

8. A device according to any of the preceding claims, wherein said at least one fixation plate comprises two plates designed to be implanted opposite each other, one on each side of the bone.

9. A device according to any of the preceding claims, wherein said at least one guiding edge is an outer edge of the fixing plate, in said second free end portion.

10. A device according to any one of claims 1 to 8, wherein said at least one guiding edge is an inner edge in an open central groove extending along the second free end portion of the fixing plate.

11. A device according to any one of claims 1 to 8, wherein said at least one guiding edge is an inner edge in a closed central groove extending along the second free end portion of the fixing plate.

12. A device according to any of the preceding claims, wherein said guide stop comprises a means selected from the group consisting of a bar, at least one screw, at least one staple, a pocket, a cannulated bicortical screw, a non-cannulated bicortical screw, a fully threaded screw, a partially threaded screw, a screw with a self-tapping tip, a self-drilling screw, a blunt-tip screw, a bar with faceted ends.

13. A device according to any of claims 1 to 11, wherein the guide stop is a bicortical bar configured to protrude from at least one of the two cortices.

14. A device according to any of claims 1 to 11, wherein the guide stop is a mono or bicortical screw configured to generate a stop on the fixation plate, for which the screw protrudes from said cortex.

15. A device according to any of claims 1 to 11, wherein the guide stop is a cannulated screw, configured to protrude from both cortices and then be threaded by a cerclage wire or cable that embraces the metaphyseal extension of the plate that is in contact with the tip of the screw and this cerclage is fixed to the head of the screw.

16. A device according to any of the preceding claims, wherein said first anchoring end portion and said second free end portion are connected to each other through a hinge.

17. A device according to any of the preceding claims, wherein said first zone (E, M) of the bone is the epiphyseal zone of the bone and said second zone (E, M) of the bone is the metaphyseal zone of the bone.

18. A positioning guide for installing the device according to claim 1, comprising an inner part 14.a and an outer part 14.b which are movable relative to each other, wherein each of the inner and outer parts has a sector 14.a.1, 14b.1 designed to accommodate the shape of the fixing plate, said sector having two cylinders for threading installation wires, said sectors being fixed to respective arms 14.a.4 and 14.b.4 which in turn are joined to arms 14.a.5 and 14.b.5 which are telescopically coupled to each other.

19. A method of positioning the positioning guide of claim 18, comprising the steps of: Step 1: Thread, through one of the cylinders on the inner and outer parts respectively of the guide, a metaphyseal Kirschner wire previously positioned in the bone; Step 2: Assemble the telescopically coupled arms; Step 3: Position the placement guide on the profile, using the image intensifier to place one of the cylinders, which is a radiopaque hollow epiphyseal cylinder, in the center of the epiphysis, allowing the epiphyseal Kirschner wire to be placed in its correct position, and then remove the guide.

20. A method of installing the device according to claim 1, comprising the following steps: Step 1: Place a metaphyseal Kirschner wire parallel to the E physis at the front of the bone, for example 1 cm at the metaphyseal level and in the center of the bone in the profile, looking for the correct positioning with the image intensifier; Step 2: Assemble the placement guide on the Kirschner wire, through the cylinder, which allows locating the correct positioning of the epiphyseal Kirschner wire; Step 3: Place an epiphyseal Kirschner wire through the guide and remove it; Step 4: Drill with a cannulated drill bit through the metaphyseal wire and place a bicortical cannulated screw, from the side that is in front of the plate, so that when turning it is positioned anteriorly and its removal is facilitated, positioning the bicortical screw so that it protrudes half a centimeter on each side of the bone, to generate the metaphyseal guide stop; Step 5: Perform a 3 cm internal and external epiphyseal approach, centered on the Kirschner wire for correct sliding of the epiphyseal plate, sliding the plate until it comes into contact with the second extreme portion or metaphyseal extension, with the guide stop already installed. The sliding of the plate can be facilitated by placing a threaded guide sleeve in the central locking hole and thus using it as a handle; Step 6: Remove the epiphyseal Kirschner wire, position the plate with the centralizing hole where the Kirschner wire was and drill through the locking sleeve, placing the locked centralizing screw through the plate, then placing the second locked screw on each side, closing in layers by performing a correct washing and hemostasis and controlling the final positioning of the device with an image intensifier.