Fastening system and fastening kit for ligamentoplasty

Abstract

The invention relates to a fastening system for ligamentoplasty, the system comprising: * a cage (100) that comprises: a longitudinal hole (101) comprising a proximal through-end (102) and a distal through-end (103); an outer surface comprising threading (104); a distal portion (105) in which the hole (101) is frustoconical; and a medial portion (106); * an internal part (200) that is intended to be inserted into the hole (101) in the cage (100), which part comprises: a frustoconical distal portion (201); a central portion (202); and a proximal portion (203) comprising threading (204); characterised in that the cage (100) comprises: - a proximal portion (107) having a larger cross-section than the medial portion (106) so as to form a collar, and wherein the cross-section of the hole (101) is larger than that of the medial portion (106), the hole (101) comprising, over an angular sector (109) of less than 360° (a portion of its periphery), threading (111) that is intended to co-operate with the internal part (200).

Description

[0001] “Fixation system and fixation kit for ligament reconstruction”

[0002] TECHNICAL FIELD OF THE INVENTION

[0003] The present invention relates to the field of ligament reconstruction. The invention will find its application in particular for the reconstruction of the cruciate ligament, preferably in animals the cranial cruciate ligament (CCL), but possibly in humans in particular for the cruciate ligaments of the knee.

[0004] STATE OF THE ART

[0005] In cases of cranial cruciate ligament rupture, ligament reconstruction is rarely performed in veterinary medicine today. This is due to the etiopathogenesis of the lesion and the varied morphological specificities of the animal. Added to this are difficulties related to tools and implants that are not suitable.

[0006] In human medicine, it is fairly well known that damaged anterior cruciate ligaments can be repaired by grafting a physiologically bonded tendon graft to bone blocks at each end, between the femur and tibia in the knee joint. The graft is inserted into a prepared hole and initially secured with a screw inserted into the hole. After a certain time, healing or incorporation of the graft is achieved.

[0007] Although this technique generally works well, problems can arise in that the screw head rests against the graft material and, when the knee is bent and the graft rotates, the screw head acts as a fulcrum for the graft and can damage the grafted fibers. Other problems can arise in that the threads of the screws used cut, and therefore damage, the graft. Other technical limitations of this system are also the compression generated by the bone / tendon / screw fixation system contributing to ovalization of the bone tunnel by necrosis of bone cells due to excessive mechanical stimuli and infiltration of synovial fluid into the bone tunnel. Although the consequence is minor for fixation, this poses problems for surgical revision with less bone stock.

[0008] Additionally, screws can, in some procedures, be lost in the knee joint cavity, causing a longer than necessary operation and additional trauma.

[0009] A recognized surgical technique used in ACL reconstruction of a damaged knee joint involves the use of a dedicated interference screw, but this is highly dependent on bone quality and therefore constitutes a barrier to the development of this technique.

[0010] This technique aims to reconstruct the ligament using hamstring tendons taken from the patient and placed in the knee joint through small bone tunnels made in the tibia and femur.

[0011] Suspension strips are frequently used, arranged at each end of the ligament graft and intended to be fixed in previously prepared bone tunnels.

[0012] Fixing the strips and not the graft in the bone tunnels provides high tensile strength and limits the risk of the graft tearing or slipping, which at least partially limits the phenomenon of bone necrosis by eliminating fixation by bone / tendon / screw interference effect.

[0013] The technique for preparing a graft is well known to those skilled in the art.

[0014] It is known to use interference screws which are introduced into the bone tunnels in order to hold the suspension strips in position.

[0015] Many interference screws are already known. However, these screws, which allow the strips or grafts to be blocked against the wall of the bone tunnel, have the disadvantage of increasing the risk of damaging the bone in the bone tunnel, which must withstand the numerous forces of the strips or grafts over time, and do not solve the problem posed by the interference fixation system by modifying a bone / tendon / screw fixation by a bone / strip / screw sandwich fixation.

[0016] There are also known devices for ligament reconstruction which include, in addition to an interference screw, a cage to be anchored in the bone tunnel and into which the strips or grafts are inserted and the interference screw to limit the weaknesses of the bone by controlling the interface between the parts.

[0017] Document FR2924596 describes a fixation device for ligament reconstruction comprising a hollow cage having an internal bore opening at each end of said cage and an external wall on which a thread is arranged, a locking member configured to be inserted into the internal bore of the cage, characterized by the fact that the thread is made of blunt threads, and by the fact that the external wall of the cage ends at the upper end by the thread or by a smooth part having an external diameter less than or equal to the internal diameter of said thread. The cage has a cylindrical external shape allowing its full insertion into the formed bone tunnel. The internal wall of the bore of the cage comprises a thread in the proximal part intended to cooperate with the thread of the locking member. The strips or grafts pass through the cage within the bore.The internal wall comprises two longitudinal grooves serving as housing for the strips. This device, although having improved the results in ligament reconstruction, still has weaknesses with risks of breakage or slippage of the suspension strips over time, particularly at the tightening points between the cage and the locking member, in particular the fixation point is proximal limiting the rigidity of the reconstruction and the two technical functions ensured by the thread of the counterscrew, namely: fixing of the strip by counterscrew and locking of the counterscrew in the cage with cyclic forces leading to a risk of loosening of the counterscrew. The present invention aims to propose a solution which makes it easier to put the system in place and optimize its durability over time.

[0018] Other objects, features, and advantages of the present invention will become apparent from the following description and accompanying drawings. It is understood that other advantages may be incorporated.

[0019] SUMMARY OF THE INVENTION

[0020] To achieve this objective, according to one embodiment, a fixation system for ligament reconstruction is provided comprising:

[0021] A cage comprising a longitudinal bore comprising a proximal end opening and a distal end opening, an outer surface comprising a thread, a distal portion in which the bore is frustoconical, a medial portion, an internal part intended to be inserted into the bore of the cage comprising a frustoconical distal part, a central part, a proximal part comprising a thread, characterized in that the cage comprises: a proximal portion of cross-section greater than that of the medial portion so as to form a collar and in which the bore has a cross-section greater than that of the medial portion, the bore comprising on an angular sector less than 360° a thread intended to cooperate with the internal part.

[0022] This system thus allows for both initial and long-term superior support thanks to satisfactory anchoring of the cage, notably due to the collar ensuring support close to the bone surface and the presence on only part of the thread for cooperation between the cage and the internal part in the proximal portion, reducing the forces on the graft. In addition, this configuration of the thread in the proximal portion frees up space in this area, facilitating the insertion of the internal part into the cage hole, even in the presence of the graft, without effort or risk of damaging it.

[0023] Advantageously, the proximal portion of the cage comprises an enlargement of the drilling at the proximal end in the angular sector complementary to the angular sector comprising the thread so as to form a notch. This arrangement further increases the volume available for the graft in this area to facilitate the introduction of the internal part and tightening without damaging the graft.

[0024] The system according to the invention provides distal fixation which avoids the disadvantages of the prior art. The system increases the stiffness of the reconstruction by fixing the point closest to the joint.

[0025] In addition, the system ensures fixation without impact on the graft.

[0026] Another aspect relates to a cage drive system comprising a distal end complementary to the proximal portion of the cage having a section having a cylindrical zone which corresponds to the angular sector provided with the thread and an oblong zone corresponding to the angular sector without the thread. Another aspect of the invention relates to an ancillary comprising at least one element for connection to the proximal portion of the cage and a distal opening configured to ensure the guidance of a tool for fixing the internal part.

[0027] Another aspect of the invention relates to a kit for ligament reconstruction comprising a system as described above and / or a cage drive system and / or an ancillary and / or a tool for guiding the internal part.

[0028] BRIEF DESCRIPTION OF THE FIGURES

[0029] The aims, objects, as well as the characteristics and advantages of the invention will emerge more clearly from the detailed description of an embodiment thereof which is illustrated by the following accompanying drawings in which:

[0030] Figure 1 represents a longitudinal sectional view of the system according to the invention.

[0031] Figure 2 represents a longitudinal sectional view of the system according to Figure 1 including the graft arranged between the cage and the internal part.

[0032] Figure 3 shows a side view of the cage of the system according to the invention.

[0033] Figure 4 represents a longitudinal sectional view of the cage of the system according to the invention.

[0034] Figure 5 represents a proximal view of the cage of the system according to the invention.

[0035] Figure 6 shows a distal view of the cage of the system according to the invention.

[0036] Figure 7 shows a side view of the internal part of the system according to the invention.

[0037] Figure 8 represents a longitudinal sectional view of the internal part of the system according to the invention.

[0038] Figure 9 represents a proximal view of the internal part of the system according to the invention.

[0039] Figure 10 shows a perspective view of the cage drive system of the system according to the invention.

[0040] Figure 11 shows a longitudinal sectional view of the cage drive system of the system according to the invention.

[0041] Figure 12 shows a side view of the cage drive system of the system according to the invention.

[0042] Figure 13 shows a distal view of the cage drive system of the system according to the invention.

[0043] Figure 14 represents a perspective view of the right side of the ancillary according to the invention.

[0044] Figure 15 represents a perspective view of the left side of the ancillary according to the invention.

[0045] Figure 16 shows a view of the right side of the ancillary according to the invention.

[0046] Figure 17 shows a view of the left side of the ancillary according to the invention.

[0047] Figure 18 represents a view from below of the ancillary according to the invention.

[0048] Figure 19 represents a top view of the ancillary according to the invention.

[0049] Figure 20 represents a perspective view of the right side of the ancillary on which the cage is associated.

[0050] Figure 21 represents a perspective view of the left side of the ancillary on which the cage is associated.

[0051] Figure 22 shows a view of the left side of the ancillary to which the cage is attached.

[0052] The drawings are given by way of example and are not limiting of the invention. They constitute schematic representations of principle intended to facilitate the understanding of the invention and are not necessarily to the scale of practical applications.

[0053] DETAILED DESCRIPTION OF THE INVENTION

[0054] Before commencing a detailed review of embodiments of the invention, optional features which may optionally be used in combination or alternatively are set out below:

[0055] According to one example, the proximal portion 107 of the cage 100 has an outer surface devoid of threads;

[0056] According to one example, the proximal portion 107 of the cage 100 comprises a widening of the drilling 101 at the proximal end 102 in a complementary angular sector 110 of the angular sector 109 comprising the thread 111 so as to form a notch 112;

[0057] According to one example, the angular sector 109 of the drilling 101 comprising the thread 111 is between 90° and 270°, preferably between 100° and 250°, preferably of the order of 240°;

[0058] According to one example, the bore 101 is reamed in the distal portion 105 and in the medial portion 106;

[0059] According to one example, the distal portion 201 of the internal part 200 is smooth;

[0060] According to one example, the central portion 202 of the internal part 200 is at least partially cylindrical and smooth and has a section smaller than that of the distal portion 201;

[0061] According to one example, the proximal part 203 of the internal part 200 has a larger section than that of the central part 202; The notch is free from the internal part when the latter is inserted into the cage;

[0062] According to one example, the cage 100 comprises fenestrations 113 intended for the osteointegration of the system, preferably, the fenestrations are of a dimension of the order of a millimeter;

[0063] According to one example, the ancillary 500 comprises a plurality of connection elements arranged around the periphery of the distal opening and the cage 100 comprises a plurality of complementary connection elements intended to cooperate with the plurality of connection elements;

[0064] According to one example, the ancillary 500 comprises a member for tensioning a graft 400.

[0065] The terms "proximal" and "distal" refer to the surgeon manipulating the fixation system. "Proximal" refers to what is closer to the surgeon than "distal" which is further from the surgeon. Right and left also refer to the surgeon when the system, instrument, or drive system are in use. The right of the instrument corresponds to the part of the instrument that is to the surgeon's right when manipulating the instrument.

[0066] Vertical means that which is parallel to the direction of gravity given in particular by the plumb line and horizontal that which is perpendicular to the vertical. The top and the bottom being vertically opposed.

[0067] By horizontal we mean that which is perpendicular to the vertical.

[0068] Transverse means a direction perpendicular to a longitudinal axis. A transverse section is a section perpendicular to the longitudinal axis.

[0069] A parameter "substantially equal / greater / less than" or "of the order of" a given value means that this parameter is equal / greater / less than the given value, to within plus or minus 10%, or even plus or minus 5%, of this value.

[0070] For the purposes of this disclosure, the expression "A and / or B" means (A), (B) or (A and B). For the purposes of this disclosure, the expression "A, B and / or G" means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C).

[0071] The present invention relates to a fixation system for ligamentoplasty. The system according to the invention is intended in particular for a veterinary application. The system is intended to allow the fixation of a biological implant, also called natural, or synthetic, ensuring the surgical treatment of a chronic or traumatic tendon or ligament condition. In the present application, the term graft 400 is used, which includes synthetic ligament grafts, biological ligament grafts, synthetic tendon grafts and biological tendon grafts. Preferably, the system is intended for the fixation of a single graft 400. The graft 400 is advantageously in the form of a strip. The strip may be in the form of a braid that may be round or flat.

[0072] The system according to the invention comprises two cooperating parts: a cage 100 and an internal part 200. Advantageously, the two parts act as a counterscrew allowing the graft 400 to be locked by a second screw of lesser caliber.

[0073] The cage 100 comprises a distal end 103 and a proximal end 102. The longitudinal axis 114 of the cage 100 passes through both the distal 103 and proximal 102 ends of the cage.

[0074] The cage 100 comprises a bore 101 advantageously passing through the cage in its largest dimension and preferably along its longitudinal axis 114. The bore 101 is advantageously centered in the cage 100. According to a possibility not shown, the bore 101 is off-center in the cage 100. The bore 101 preferably opens at each end of the cage: at the proximal end 102 and at the distal end 103. The bore is a tunnel passing right through the cage 100. The cage 100 is hollow. The cage is a so-called female part.

[0075] Advantageously, the cage 100 is configured to allow the introduction of the internal part 200 into said cage 100 and more precisely into the bore 101. The bore 101 is for example of circular cross-section, in particular with the exception of the proximal portion 107. The bore 101 forms an interior surface 115 of the cage 100.

[0076] The cage 100 comprises an outer surface advantageously intended to be in contact with the animal or human body, more precisely in contact with the bone into which the system is intended to be inserted. The cage 100 is advantageously introduced by a drive system 300 into a drilling previously formed in the bone. The outer surface of the cage advantageously has a rough surface condition optimizing bone anchoring, for example a roughness Ra of between 1.6 and 20.

[0077] The cage 100 has a cross-section configured to allow the cage 100 to be screwed. Preferably, the cage 100 has a circular external cross-section.

[0078] According to one embodiment, the outer surface comprises a thread 104. The outer surface is advantageously only partially covered with the thread 104. The thread 104 is intended to ensure anchoring in the bone. The thread 104 is advantageously aggressive or sharp to ensure this anchoring in particular in cancellous bone.

[0079] According to one embodiment, the cage 100 comprises a distal portion 105 extending from the distal end 103 towards the proximal end 102 and advantageously to a medial portion 106. The distal portion 105 of the cage 100 comprises the piercing 101 which has a frustoconical shape in this distal portion 106. The piercing 101 has a cross-section narrowing towards the distal end 105. According to one embodiment, in the distal portion 105, the inner surface 115 of the cage 100 formed by the piercing 101 has an inclination of between 5° and 80°, preferably between 12 and 20° relative to the longitudinal axis. This inclination is preferably made towards the outside of the cage and in the direction of the proximal end 102. This inclination is advantageously chosen to ensure continuous contact allowing optimal fixation of the graft 400 while limiting friction with the graft 400.

[0080] According to one possibility, the thread 104 of the outer surface of the cage 100 extends at least partially over this distal portion 105. The distal portion 105 has, according to one possibility, a circular outer cross-section.

[0081] According to one embodiment, the cage 100 comprises a medial portion 106 extending from the distal portion 105 towards the proximal end 102 and advantageously to a proximal portion 107. The thread 104 advantageously extends on the outer surface of this medial portion 106 of the cage 100. The medial portion 106 of the cage comprises the bore 101 which has in this medial portion 106 an advantageously constant internal cross-section. According to a preferred possibility, the medial portion 106 comprises an internal cross-section of diameter greater than the diameter of the internal part 200 intended to be inserted into the cage 100. This allows both the internal part 200 to slide in the bore 101 and at the same time to provide a volume in which the graft 400 is positioned. According to another possibility not shown, the medial portion 106 comprises a groove extending longitudinally in the piercing.Preferably, the system comprises a single groove, the groove being intended to receive the graft 400. Advantageously, the internal cross-section of the medial portion 106 is of a dimension greater than or equal to the largest internal cross-section of the distal portion 105.

[0082] According to a preferred embodiment, the inner surface 115 of the cage extends into the distal portion 105 and into the medial portion 106 such that the change in inclination between the distal portion 105 and the medial portion 106 is without a sharp angle. The acute angle formed between the inner surface 115 at the distal portion 105 and the inner surface at the medial portion 106 is greater than 90°, preferably of the order of 140 to 170°.

[0083] According to one embodiment, the cage 100 comprises a proximal portion 107 extending from the proximal end 102 towards the distal end 103, preferably up to the medial portion 106. Preferably, the proximal portion 107 does not comprise a thread 104. Preferably, the thread 104 stops at the junction between the medial portion 106 and the proximal portion 107.

[0084] The proximal portion 107 advantageously has a collar. The collar is formed by a cross-section of the outer surface of the cage 100 greater than that of the medial portion 106. According to one possibility, the cross-section of the outer surface of the cage 100 increases towards the proximal end 102. The collar shape of the proximal portion 107 makes it possible to provide cortical support to the system. The proximal portion 107 preferably widens towards the proximal end 102, this widening forms the collar. According to a preferred embodiment, the collar is intended not to be completely buried in the bone. Preferably at least the proximal end of the proximal portion 107 remains above the surface of the bone.

[0085] The proximal portion 107 of the cage comprises the bore 101 which has in this portion an internal cross-section greater than that of the medial portion 106. The bore 101 comprises in this proximal portion 107, a thread 111 extending over an angular sector 109 of the bore 101 less than 360°. Thus, the drilling 101 comprises a portion of its periphery not comprising a thread 111, it is a complementary angular sector 110 not having a thread 111. The absence of a thread 111 on an angular sector 110 makes it possible to avoid damaging the graft 400 which is advantageously arranged in this angular sector 110 while the angular sector 109 is intended to cooperate with a complementary thread 204 of the internal part 200. Advantageously, the thread 111 extends over a single angular sector of the drilling 101 less than 360°. The drilling 101 comprises only a portion of its periphery not comprising a thread 111.The drilling 101 comprises a single angular sector less than 360° comprising the thread 111 and a single portion not comprising a thread 111. The portion not comprising a thread 111 and the angular sector comprising the thread represents an angular sector of 360°.

[0086] According to a preferred embodiment, the proximal portion 107 comprises a widening of the drilling 101 on the complementary angular sector 110 not having a thread 111. This widening forms a notch 112 contributing to allowing the passage of the graft 400 without damaging it.

[0087] Advantageously, the angular sector 109 comprising the thread 111 extends over an angular sector less than or equal to 300°, preferably less than or equal to 270°, preferably less than or equal to 250°. Advantageously, the angular sector 109 having the thread 111 extends over an angular sector greater than or equal to 90°, preferably greater than or equal to 100°, preferably greater than or equal to 180°. Advantageously, the angular sector 109 comprising the thread 111 extends over an angular sector between 90° and 300°, preferably between 100° and 270°, preferably between 180° and 250°. Preferably, the angular sector 109 is continuous or uninterrupted, that is to say that it is formed in a single part and not from a plurality of sections the sum of which would correspond to a total angular sector less than or equal to 300°.

[0088] The thread 111 is intended to cooperate with the internal part 200.

[0089] According to a preferred embodiment, the cage 100 comprises fenestrations or lumens 113 passing through the wall of the cage 100 so as to put the piercing 101 and the outer surface of the cage 100 into communication. The lumens 113 have a diameter of the order of a millimeter. The lumens 113 allow better circulation of the cells inducing good osteointegration of the cage 100.

[0090] The drilling 101 is advantageously reamed in particular in the distal portion 105 and preferably also in the medial portion. The drilling 101 is therefore smooth at least in this or these portions. This reaming makes it possible to avoid any damage to the graft 400.

[0091] At the distal end 103 of the cage 100, the piercing 101 has an oblong-shaped mouthpiece, that is to say one whose cross-section is preferably elongated in shape, the edges of which are broken or softened so as to facilitate the passage of the implant without damaging it.

[0092] The invention comprises an internal part 200. The internal part 200 is configured to be inserted into the cage 100, more precisely into the drilling 101. The internal part 200 has the main function of ensuring the locking of the graft 400 in the cage 100. Advantageously, the internal part 200 is a solid part.

[0093] The internal part 200 has a distal end 205 and a proximal end 206. The longitudinal axis 208 of the internal part 200 passes through both the distal 205 and proximal 206 ends of the internal part. The longitudinal axis 114 of the cage 100 and the longitudinal axis 208 of the internal part 200 are, according to one embodiment, parallel, or even coincident. According to another embodiment, the longitudinal axis 208 of the internal part 200 is offset relative to the longitudinal axis 114 of the cage when the graft 400 is locked between the cage 100 and the internal part 200. Indeed, this locking compressing the graft 400 between the internal surface 115 of the cage and the internal part 200 slightly offsets the internal part 200 and in particular its distal part 201 which thus also comes into contact or even into compression against the internal surface 115 of the cage opposite the graft 400.

[0094] According to another embodiment, the longitudinal axis 114 of the cage and the longitudinal axis 208 of the internal part 200 are parallel, but not coincident. This arrangement is possible when the bore 101 is not centered in the cage 100, in particular when the cage comprises a single groove formed parallel to the bore 101.

[0095] The internal part 200 comprises a distal portion 201 extending from the distal end 205 towards the proximal end 206 and advantageously to a central portion 202. The distal portion 205 is advantageously frustoconical in shape. The distal portion 201 has a cross-section widening from the distal end 205 towards the proximal end 206. The distal portion 201 is configured to fit into the distal portion 105 of the cage 100.

[0096] The internal part 200 comprises a central portion 202 extending from the distal portion 201 towards the proximal end 206 and advantageously up to the proximal portion 203. The central portion 202 has a preferably constant cross-section. The cross-section of the central portion 202 is less than or equal to the largest cross-section of the distal portion 201. In the case where the cross-section of the central portion 202 is less than the largest cross-section of the distal portion 201, this provides a space between the cage 100 and the internal part 200, more precisely between the medial portion 106 and the central portion 202. This configuration makes it possible to provide more space for the graft in this medial portion 206.

[0097] The internal part 200 comprises a proximal portion 203. The proximal portion 103 extends from the proximal end 205 towards the distal end 205 and advantageously to the central portion 202. The proximal portion 203 advantageously comprises a thread 204. The thread 204 is advantageously formed on at least a portion of the proximal portion 203. The thread 204 is configured to cooperate with the thread 111 of the cage 100. Preferably, the proximal portion 203 has a first sub-portion 203a of frustoconical shape and preferably without a thread. The first sub-portion 203a extends from the central portion 202 towards the second sub-portion 203b. The second sub-portion 203b extends from the first sub-portion 203a towards the proximal end 206 and is advantageously of constant circular cross-section.

[0098] The distal portion 203 comprises an imprint 207 advantageously formed at the proximal end 206. The imprint 207 is intended and configured to cooperate with a tool for placing the internal part 200 in the cage 100.

[0099] According to one aspect, the invention relates to a method for fixing a system according to the invention for ligament reconstruction. The method advantageously comprises drilling into the bone. The method comprises placing the cage 100 in a drilling previously made in the bone. The installation is advantageously carried out by the drive system 300 as described above and shown in Figures 10 to 13. Once the cage 100 is implanted, the graft 400 is passed through the cage 100, more precisely through the perforation 101. The graft 400 is advantageously placed at the proximal end 102 in the notch 112 of the proximal portion 107. The internal part 200 is then placed in the cage 100 preferably using a tool, not shown, intended to cooperate with the impression 207 of the internal part 200.The distal end 205 of the internal part 200 is introduced into the drilling 101, preferably while maintaining the graft in the notch 112. The proximal part 203 and more specifically the thread 204, advantageously of the sub-part 203b, cooperates with the thread 104 of the proximal portion 107. The internal part 200 is screwed into the cage 100. The internal part 200 and more specifically the distal part 201 is applied to the graft 400 which is itself applied to the internal surface 115 of the distal portion 105 of the cage 100, thus ensuring the fixation of the graft 400.

[0100] The system according to the invention thus allows locking of the graft 400 in the system according to the invention by compression between the cage 100 and the internal part 200.

[0101] According to one embodiment, the cage 100 and the internal part 200 are made of metal such as, for example, titanium, stainless steel or Polyether ether ketone (PEEK). The cage 100 and the internal part 200 are, for example, manufactured by machining, molding or additive manufacturing such as 3D printing. This allows the manufacture of internal structures with complex curves, but also the obtaining of a rough surface state suitable for bone anchoring or even trabecular and / or porous structure.

[0102] According to one aspect, the invention relates to a drive system 300 intended to cooperate with the cage 100 to ensure its placement in a bone drilling.

[0103] According to one aspect, the invention relates to a kit comprising the fixation system for ligament reconstruction comprising the cage 100 and the internal part 200 as well as the drive system 300. Advantageously, the drive system 300 for positioning the cage 100 is cannulated to allow the implantation of the system along the axis of the bone drilling carried out beforehand.

[0104] The drive system 300 for positioning the cage 100 is illustrated in Figures 10 to 13.

[0105] The drive system 300 comprises a distal end 301 intended to cooperate with the proximal end 102 of the cage 100 and a proximal end 304 advantageously intended to cooperate with a geared motor for rotational actuation of the tool 300.

[0106] The drive system 300 comprises a complementary zone 305 of the section of the piercing 101 and more particularly of the medial portion 106. The complementary zone 305 advantageously has a circular cross-section of constant diameter. This complementary zone 305 has a maximum length corresponding to the length of the medial portion 106. This zone 305 extends from the distal end 301 preferably to the intermediate zone 306. The intermediate zone 306 is configured to cooperate with the proximal portion 107 of the cage 100. The intermediate zone 306 comprises a first zone called the oblong zone 303 and a second zone called the circular zone 302. The oblong zone 303 extends over an angular sector corresponding to the angular sector 110 complementary to the angular sector 109 of the cage 100. The circular zone 302 extends over an angular sector corresponding to the angular sector 109 of the cage 100.The circular zone 302 has a circular external surface in the extension of the complementary zone 305. The oblong zone 303 has a circular external surface prominent relative to the complementary zone 305. Preferably, the tool 300 comprises a stop surface 307 intended to be applied to the proximal end 102 of the cage 100.

[0107] According to one possibility, the invention comprises a tool for placing the internal part 200. This tool is not shown in the figures. The tool for placing the internal part 200 is configured to cooperate with the imprint 207 of the internal part 200. According to one possibility, the tool for placing the internal part 200 may be part of a ligament reconstruction kit.

[0108] According to one aspect, the invention relates to an ancillary 500 intended to cooperate with the cage 100 for the positioning of the internal part 200 and the tensioning of the graft 400.

[0109] According to one aspect, the invention relates to a kit comprising the fixation system for ligament reconstruction comprising the cage 100 and the internal part 200, as well as the ancillary 500 and advantageously the drive system 300 and possibly the tool for positioning the internal part 200.

[0110] The ancillary 500 comprises a distal portion 501 and a proximal portion 511 forming a handle 505 intended to be grasped by the surgeon. The handle 505 is for example flattened to facilitate its grip.

[0111] The distal portion 501 and the proximal portion 511 join at a clamping assembly. The clamping assembly comprises a transverse opening formed in the ancillary and receiving a clamping shaft 509; the clamping shaft 509 receiving at one end a clamping wheel 508 that can be actuated by hand and at its other opposite end, a counter-holding spring 510. Advantageously, the clamping shaft 509 comprises a slot 507 configured and intended to receive the graft 400 to ensure its tensioning by actuation of the clamping wheel 508.

[0112] The distal portion 501 comprises an opening 502. The opening 502 is advantageously perpendicular to the opening receiving the clamping axis 509. The opening 502 is configured to receive at least the tool for positioning the internal part 200. According to one possibility, the opening 502 is also configured to allow the passage of the internal part 200.

[0113] The distal portion 501 is configured to cooperate with the cage 100 and more specifically with the proximal end 102. The distal portion 501 is advantageously intended to cooperate with the cage 100 to hold it in place in the bone tunnel during the insertion of the internal part 200 and its tightening. The distal portion 501 comprises at least one connection element intended to cooperate with the cage 100. Preferably, the cage 100 comprises a complementary connection element intended to cooperate with the connection element of the ancillary 500. The connection element is configured to prevent rotation of the cage 100 during rotation of the internal part 200.

[0114] According to a preferred embodiment, the ancillary 500 comprises a plurality of connection elements. As a preferred example, the connection element is a protrusion 503 extending from the distal portion in a direction parallel to the axis of the opening 502. The protrusion 503 is preferably arranged on the periphery of the opening 502 so as to leave the entire section of the opening 502 free for the passage of the tool for positioning the internal part 200. According to one possibility, the ancillary 500 comprises four protrusions 503 as illustrated in FIGS. 14 to 22.

[0115] According to this embodiment, the complementary connection elements are recesses 506 of a shape complementary to the protuberances 503. The recesses 506 are advantageously formed in the proximal portion 107 and more particularly at the level of the collar. The recesses are formed for example at least partially in the thickness of the proximal portion 107 as illustrated in FIGS. 20 to 22 where the recesses 506 are made on the outer surface of the proximal portion 107, the recess 506 having a shape at least partially complementary to a protuberance 503.

[0116] According to a preferred possibility, the ancillary comprises a stop 504 formed on the distal portion 501. The stop 504 is of a shape complementary to a portion of the periphery of the proximal portion 107 of the cage 100, that is to say to the circumference of the collar. The stop 504 is preferably formed at the periphery of the opening 502. The stop 504 is for example arranged at the distal end of the distal portion 501. The stop 504 advantageously faces the protuberances 503.

[0117] According to one possibility, the method of fixing a system according to the invention for ligament reconstruction, as described above, is repeated with the use of the ancillary 500. The method advantageously comprises drilling into the bone. The method comprises placing the cage 100 in a drilling previously made in the bone. The placement is advantageously carried out by the drive system 300 as described above and shown in Figures 10 to 13. Once the cage 100 is implanted, the graft 400 is passed through the cage 100, more precisely through the piercing 101. The graft 400 is advantageously placed at the proximal end 102 in the notch 112 of the proximal portion 107. The internal part 200 is then placed in the cage 100. The distal end 205 of the internal part 200 is introduced into the piercing 101, preferably while maintaining the graft in the notch 112.The ancillary 500 is then put in place; the connection element of the ancillary 500 is fixed in the complementary connection element of the cage 100, more specifically the stop 504 and the protuberances 503 are positioned on the proximal portion 107 of the cave 100. The graft 400 is introduced into the slot 507 of the clamping assembly of the ancillary 500. The clamping wheel 508 is actuated to tension the graft 400. Then, preferably using a tool, not shown, intended to cooperate with the imprint 207 of the internal part 200, and passing through the opening 502 of the ancillary, the internal part 200 is tightened. The proximal part 203 and more specifically the thread 204, advantageously of the sub-part 203b, cooperates with the thread 104 of the proximal portion 107. The internal part 200 is screwed into the cage 100.The internal part 200 and more specifically the distal part 201 is applied to the graft 400 which is itself applied to the internal surface 115 of the distal portion 105 of the cage 100 thus ensuring the fixation of the graft 400. The positioning tool and then the ancillary 500 can be removed. The invention is not limited to the embodiments previously described and extends to all the embodiments covered by the invention.

[0118] LIST OF REFERENCES system . Cage . Drilling . Proximal end . Distal end . Thread . Distal portion . Medial portion . Proximal portion . Angular sector with thread . Angular sector without thread Thread . Notch . Lumens . Longitudinal axis of the cage . Inner surface of the cage . Internal part . Distal part . Central part . Proximal part a. First sub-part b. Second sub-part . Thread . Distal end . Proximal end . Impression . Longitudinal axis of the internal part . Drive part . Distal end . Cylindrical zone . Oblong zone . Proximal end . Complementary zone of the drilling 306. Intermediate zone

[0119] 307. Abutment surface

[0120] 400. Graft

[0121] 500. Ancillary 501. Distal part

[0122] 502. Opening

[0123] 503. Protuberances

[0124] 504. Stop

[0125] 505. Handle 506. Recesses

[0126] 507. Slot

[0127] 508. Clamping wheel

[0128] 509. Clamping axis

[0129] 5 0. Clamping spring 511. Proximal part

Claims

CLAIMS 1. Fixation system for ligament reconstruction comprising: • A cage (100) comprising i. a longitudinal bore (101) comprising a proximal end (102) opening out and a distal end (103), ii. an outer surface comprising a thread (104), iii. a distal portion (105) in which the bore (101) is frustoconical, iv. a medial portion (106), • an internal part (200) intended to be inserted into the bore (101) of the cage (100) comprising i. a truncated distal part (201), ii. a central part (202), iii. a proximal part (203) comprising a thread (204), characterized in that the cage (100) comprises a proximal portion (107) of cross section greater than that of the medial portion (106) so as to form a collar and in which the bore (101) has a cross section greater than that of the medial portion (106), the bore (101) comprising on a continuous angular sector (109) less than 360° a thread (111) intended to cooperate with the internal part (200).

2. Fixing system according to the preceding claim in which the proximal portion (107) of the cage (100) has an external surface without thread.

3. Fixing system according to any one of the preceding claims in which the proximal portion (107) of the cage (100) comprises a widening of the drilling (101) at the proximal end (102) in a complementary angular sector (110) of the angular sector (109) comprising the thread (111) so as to form a notch (112).

4. Fastening system according to any one of the preceding claims in which the angular sector (109) of the drilling (101) comprising the thread (111) is between 90° and 270°.

5. Fixation system according to any one of the preceding claims in which the piercing (101) is reamed in the distal portion (105) and in the medial portion (106).

6. Fixing system according to any one of the preceding claims in which the distal portion (201) of the internal part (200) is smooth.

7. Fixing system according to any one of the preceding claims in which the central part (202) of the internal part (200) is at least partially cylindrical and smooth and has a section smaller than that of the distal part (201).

8. Fixing system according to any one of the preceding claims in which the proximal part (203) of the internal part (200) has a larger section than that of the central part (202).

9. Fixation system according to any one of the preceding claims in which the cage (100) comprises fenestrations (113) intended for osseointegration of the system.

10. Ligamentoplasty kit comprising a system (1) according to any one of the preceding claims and a drive system (300) of the cage (100) comprising a distal end (301) complementary to the proximal portion (107) of the cage (100) having a section having a cylindrical zone (302) corresponding to the angular sector (109) provided with the thread (111) and an oblong zone (303) corresponding to the angular sector (110) without the thread (111).

11. Ligamentoplasty kit according to claim 10 comprising an ancillary (500) comprising at least one connection element to the proximal portion (107) of the cage (100) and a distal opening configured to ensure the guidance of a tool for fixing the internal part (200).

12. Ligamentoplasty kit according to the preceding claim, in which the ancillary (500) comprises a plurality of connection elements arranged around the periphery of the distal opening and the cage (100) comprises a plurality of complementary connection elements intended to cooperate with the plurality of connection elements.

13. Ligamentoplasty kit according to any one of the two preceding claims in which the ancillary (500) comprises a member for tensioning a graft (400).

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