Spinal stabilizator

Abstract

Disclosed herein is a fixator (1) for elastically restricting flexion of a spinal segment. The fixator (1) comprises a load-bearing element (4) comprising one or more load-bearing surfaces (5, 6), wherein a first load-bearing surface (5) is configured for contacting in a mounted position a first vertebra (2) and for forming in the mounted position a semi-loop (7) around the first vertebra (2). The load-bearing element (4) merges at the first end (41) into a first tail (8) and at the second end (41) into a second tail (9). The fixator (1) further comprises at least one lock (10) interconnected in the mounted position to the first tail (8) and / or the second tail (9) to maintain the load-bearing element (4) in a pre-tension with respect to a neutral position of the spinal segment, thereby providing an elastic resistance to flexion beyond the neutral position.

Description

[0001] P28894PC00 14.1 1.2025

[0002] 1 / 41

[0003] Spinal Stabilizator

[0004] FIELD OF THE DISCLOSURE

[0005] This disclosure relates to medical devices in general and more particularly to medical devices for elastically restricting spinal flexion in patients having back pain or other spinal conditions.

[0006] BACKGROUND OF THE DISCLOSURE

[0007] Spinal fusion has become a common surgical procedure, among others in the treatment of degenerative disorders of the spine. The indications for this surgical procedure are diverse and include low-back pain due to facet joint osteoarthritis, degenerative spondylolistheses, degenerative scoliosis and segmental instability. The latter can also be a result of iatrogenic destabilization following surgical resection of ligamentous structures as well as the facet joint. However, spinal fusion is associated with serious long-term complications such as adjacent segment degeneration (ASD), screw loosening, pseudarthrosis, implant failure, and, in rare cases, neurovascular injury during implant insertion. The redistribution of loads with subsequently increased biomechanical stress are believed to act as accelerators of ASD and proximal junctional kyphosis. Further, long fusions can lead to a relevant, irreversible loss of motion, which can cause postural changes.

[0008] Despite these problems, posterior spinal fusion (PSF) currently represents the gold standard. Alternative techniques of spinal stabilizations have not yet yielded satisfactory results with broad clinical impact. Previous attempts at spinal stabilization also include spinous process implants. However, studies have shown higher rates of reoperation with low cost-effectiveness, which may explain why they are hardly in use anymore. The P28894PC00 14.1 1.2025

[0009] 2 / 41 same applies to cervical wiring techniques, such as sublaminar wires for atlantoaxial fusion, which are unable to achieve sufficient stabilization.

[0010] A further technique to achieve spinal stabilization involves semi-rigid fixation techniques. These techniques aim to restrict movement of two vertebrae with respect to each other in a semi-rigid fashion. However, the known semi-rigid fixation techniques resulted in a range of new complications, including device breakage, dislocation or screw loosening at the implant-bone interface. For example, in some of the known techniques, the implant is dislocated or displaced over time, especially at the implant-bone interface. For example, certain movements of the patient, such as repeated flexion and extension, can lead to displacement of the implant e.g. in dorsal direction, but potentially also in anterior direction. A particularly challenging area of potential displacement are the spinous processes or laminae of patients which are used in some known techniques as implant- bone-interfaces. Many of the problems of the known semi-rigid fixation implants, including their uncontrolled displacement over time, can be attributed to the fact that they are unable to adjust to the specific anatomical environment and biomechanical circumstances of a specific given patient. For example, the precise contour of the spinous processes and the associated biomechanical environment in the spinal segment may differ between patients, but the known implants are often unable to accommodate for these differences appropriately.

[0011] A further disadvantage of the known semi-rigid fixation techniques is that they restrict certain directions of spinal movement too strongly, while not restricting other direction of spinal movement sufficiently. Specifically, it may be desirable to achieve effective and flexible restriction of flexion without impacting other directions of motion. Thus, there is still a need to strike a beneficial balance of selectively restricting some directions of spinal movement, e.g. flexion, while only minimally restricting other directions of spinal movement, such as torsion or extension. P28894PC00 14.1 1.2025

[0012] 3 / 41

[0013] Yet a further disadvantage of many of the known semi-rigid fixation techniques is that they employ implants that are too rigid, which leads to an unfavorable load distribution across the spine and may lead to deterioration of neighboring spinal segments that were previously healthy. Thus, there is a need to achieve a more balanced spinal fixation, with smooth motion control. There is also a need to accurately mimic the natural biomechanical properties of the diseased spinal segment.

[0014] A further disadvantage of many known semi-rigid fixation techniques is that they experience a significant change in their biomechanical properties over time, in particular a deterioration of flexion restriction over time, e.g. due to creep. There is therefore a need to improve the ability of the known devices to maintain effective spinal fixation over time.

[0015] Further disadvantages of the known techniques and devices include their inability or unsuitability to be used in conjunction with existing anatomical structures of the body. For example, some of the known implants rely on supplementary support structures or additional modifications of the existing bone structure (e.g. abrasing or otherwise processing bone surfaces prior to implantation) in order to allow placement and fixation of the implant. Furthermore, some of the existing implants are difficult to implant and require complex instrumentation e.g. for tensioning of the implant.

[0016] Accordingly, there is a need to improve the known techniques and implants for spinal fusion.

[0017] SUMMARY OF THE DISCLOSURE

[0018] It is a general object of the present disclosure to provide a fixator for elastically restricting flexion of a spinal segment comprising a first vertebra and a second vertebra, which addresses at least some of the disadvantages of the known implants and techniques. It P28894PC00 14.11.2025

[0019] 4 / 41 is a particular object to provide a fixator that effectively and flexibly restricts flexion, while minimizing the impact on other directions of movement, such as extension, rotation or lateral movements. It is a further object in at least some embodiments to achieve effective stabilization while also retaining a certain degree of flexibility, and to mimic the natural biomechanical properties of the spine without causing of unwanted disbalance in the load distribution. It is a further object of at least some variations to provide an implant with improved load distribution, especially on an implant-body-interface. In particular, it is an object of at least some variations to minimize damage to spinal structures such as spinous processes or laminae due to overload. Furthermore, negative displacement of the implant, especially on the implant-bone-interface, shall be minimized. A further object of at least some variations is to minimize tension loss over time and, ideally, to facilitate the operation of applying the tension to the implant. Yet a further object of at least some variations is to provide an implant which can be used on existing anatomical structures of the body and to minimize the need for any additional preparation steps or auxiliary structures. Ideally, the implant would be able to accommodate the specific anatomical environment and biomechanical circumstances of a given patient without the need for complex adjustments of the implant.

[0020] According to the present disclosure, a fixator is provided which is configured for elastically restricting flexion of a spinal segment comprising a first vertebra and a second vertebra. The fixator comprises a load-bearing element extending in a longitudinal direction from a first end to a second end. As will be seen hereinafter the load-bearing element when implanted can be arranged straight or with at least one bend around an existing structure. The load-bearing element comprises one or more load-bearing surfaces arranged in longitudinal direction between the first end and the second end. A first loadbearing surface is configured for contacting in a mounted position the first vertebra and for forming in the mounted position a semi-loop around a structure of the first vertebra. P28894PC00 14.1 1.2025

[0021] 5 / 41

[0022] It is understood that the first load-bearing surface is one of the one or more load-bearing surfaces.

[0023] The load-bearing element usually merges at the first end into a first tail and at the second end into a second tail. The fixator usually comprises at least one lock interconnected in the mounted position to the first tail and / or the second tail to maintain the load-bearing element in a pre-tension with respect to a neutral position of the spinal segment, thereby providing an elastic resistance to flexion beyond the neutral position.

[0024] To illustrate a possible application of the fixator, the fixator may for example be used to form a loop around and / or across an opening of the spinous processes of the first and second vertebrae. Optionally, two or even more loops may be formed. To close the last loop being applied, the first tail and the second tail may both be connected to the lock. Subsequently, the first tail and the second tail may be tensioned using the lock in order to apply a tension to the fixator, which leads to formation of a load on the vertebrae, thereby fixating the vertebrae and providing an elastic resistance to flexion. Other applications are also possible, including applications in which a semi-loop is formed around the first vertebrae and the first tail and the second tail are interconnected to the second vertebra, e.g. through one or more locks.

[0025] By using a lock that is interconnected in the mounted position to the first tail and / or to the second tail, the fixator facilitates application of a tension on the fixator, respectively a respective force onto the thereto interconnected surrounding structures. The use of a lock interconnected to the first and / or second tail also makes it easy to adjust the fixator to the specific biomechanical requirements and anatomical environment of a given patient. For example, when the lock is interconnected to the first tail and to the second tail, the position of the lock between the first end and the second end may be chosen in accordance with the patient-specific anatomical environment. A further advantage is that P28894PC00 14.1 1.2025

[0026] 6 / 41 the material and design of the load-bearing element may be chosen to provide an elasticity that is compatible with the patient-specific requirements.

[0027] The mounted position, as used herein, refers to a position of the fixator in which the fixator has been applied to a spinal segment in order to elastically restrict flexion of the spinal segment, respectively the vertebrae forming part of the spinal segment with respect to each other. In the mounted position, the first load-bearing surface contacts the first vertebra. Furthermore, in the mounted position, the load-bearing element is under a pre-tension when the spinal segment is in a neutral (natural) position. As the spinal segment is subjected to flexion or extension, the tension on the load-bearing element may change.

[0028] The load-bearing element is configured to maintain in the mounted position a pre-tension with respect to a neutral position of the spinal segment. The load-bearing element is further configured to bear a load resulting from a movement of the spinal segment beyond its neutral position, especially flexion of the spinal segment beyond its neutral position.

[0029] The load-bearing element may comprise one or more load-bearing surfaces arranged between the first end and the second end. The first load-bearing surface is configured for contacting in the mounted position the first vertebra. Thus, the first load-bearing surface may receive a load resulting from a movement of the spinal segment beyond its neutral position, especially flexion of the spinal segment beyond its neutral position.

[0030] Depending on the application, different load-bearing elements may be used, which allows fine-tuning of the load-bearing properties of the load-bearing element. For example, a load-bearing element with a deformable cross-section may be used in order to distribute the load across a larger surface and therefore to minimize the risk of tear or other P28894PC00 14.1 1.2025

[0031] 7 / 41 damage on the fixator and to minimize potential damage of the first vertebra. In some variations, the load-bearing element is essentially strap-like, at least in the region of the one or more load-bearing surfaces. Furthermore, the load-bearing element may have a deformable cross-section which in the mounted position flattens in lateral direction when in contact with a vertebra in the region of a load-bearing surface, such that the load is distributed in lateral direction. In some variations, the cross-section of the load-bearing element in the region of the one or more load-bearing surfaces is configured such that the one or more load-bearing surfaces mould on themselves to a topography of an outer surface of the first and / or second vertebra when in contact with the first and / or second vertebra. In the case of the first load-bearing surface, for example, the cross-section of the load-bearing element in the region of the first load-bearing surface may optionally be configured such that the first load-bearing surface moulds on itself to a topography of an outer surface of the first second vertebra when in contact with the first vertebra.

[0032] The variations described in the previous paragraph allow to distribute the load across a larger surface of the vertebrae which is usually not possible by the devices known from the prior art. This may be useful to minimize the risk of tear or other damage to the fixator, and also reduce the risk of potential damage to the first vertebra, particularly to the spinous process of the first vertebra. For example, when the first load-bearing surface contacts a spinous process of the first vertebra, the flattening in lateral direction leads to distribution of the load across a larger surface area of the spinous process, thereby reducing the risk of the implant cutting into the spinous process or leading to other deformations or destructions of the spinous process.

[0033] A further advantage is that the flattening can also be used to increase the grip of the fixator on the first vertebra, thereby minimizing the risk of uncontrolled displacement of the load-bearing element. For example, when the load-bearing element forms a semiloop around a spinous process of the first vertebra, there could be a risk of dorsal or P28894PC00 14.1 1.2025

[0034] 8 / 41 anterior displacement of the load-bearing element. However, upon flexion of the spinal segment, flattening of the deformable cross-section in lateral direction may be used to increase the contact area on which the load-bearing element contacts the first vertebra, thereby reducing the risk of displacement of the load-bearing surface with respect to the first vertebra. Furthermore, at least in some variations, flexion may initially lead primarily to flattening of the cross-section before further increased flexion ultimately primarily transfers into an axial load on the load-bearing element. By initially primarily leading to flattening of the cross-section, the grip is increased before a potential risk of displacement (e.g. in dorsal or anterior direction) arises. Consequently, these embodiments may advantageously be used to ensure that the fixator displays a high locational stability. In particular, uncontrolled displacements (e.g. in dorsal or anterior direction) are minimized. This is advantageous because dorsal or anterior displacements may lead to changes in the lever ratios.

[0035] The term lateral direction, as used herein, usually refers to a direction orthogonal to the longitudinal direction. It does not necessarily indicate an anatomical direction opposite a medial direction.

[0036] In some variations, the cross-section of the load-bearing element is deformable. Depending on the application, the cross-section may be deformable only in the region of the one or more load-bearing surfaces, or also in regions of the load-bearing element that are outside the region of the one or more load-bearing surfaces. In some variations, the loadbearing element has a deformable cross-section across all sections arranged in longitudinal direction between the first end and the second end. In some variations, the deformability of the cross-section of the load-bearing element may be higher in the region of the one or more load-bearing surfaces than it is in regions outside the one or more loadbearing surfaces. In further variations, however, the deformability of the cross-section of P28894PC00 14.1 1.2025

[0037] 9 / 41 the load-bearing element is the same in the region of the one or more load-bearing surfaces as it is in regions outside the one or more load-bearing surfaces.

[0038] In variations in which the cross-section of the load-bearing element is deformable, the shape and geometry of the cross-section may change depending on the spinal position. For example, flexion may lead to widening of the cross-section of the load-bearing element in the region of the one or more load-bearing surfaces. Depending on the application, a change in cross-section may optionally also occur in regions outside the one or more load-bearing surfaces. However, in a typical variation, the cross-section of the loadbearing element in the region of the one or more load-bearing surfaces widens more than the cross-section of the load-bearing element in a region outside the one or more load-bearing surfaces when the spinal segment is flexed in the mounted position.

[0039] In some variations, in the mounted position the cross-section of the load-bearing element in the region of the one or more load-bearing surfaces is wider in lateral direction than the cross-section of the load-bearing element in a region outside the one or more loadbearing surfaces. These variations may in particular refer to the neutral position of the spinal segment and may preferably also apply to positions in which the spinal segment is flexed beyond the neutral position.

[0040] Depending on the application, the load-bearing element may have different cross-sections. In some variations, the cross-section of the load-bearing element is essentially oval, such as essentially round, in the region of the one or more load-bearing surfaces. Optionally, the cross-section of the load-bearing element may also be essentially oval, such as essentially round, in a region outside the one or more load-bearing surfaces.

[0041] In some variations, the cross-section of the load-bearing element varies along the longitudinal direction. For example, in some variations, the load-bearing element comprises P28894PC00 14.1 1.2025

[0042] 10 / 41 or even consists of a graft with a cross-section that varies along the longitudinal direction of the graft.

[0043] Depending on the application, the elastic properties of the load-bearing element may differ in different directions. For example, in some variations, the load-bearing element has a lower elasticity in longitudinal direction than in lateral direction. As an example, in some variations, the load-bearing element may have a higher modulus of elasticity in longitudinal direction than in lateral direction.

[0044] The fixator usually comprises a first tail and a second tail. The first tail and / or the second tail are configured to interconnect the load-bearing element to the lock and / or an adjacent structure. Furthermore, the first tail and / or the second tail may be configured to withstand a tensile stress in the mounted position.

[0045] Depending on the application, different first and second tails may be used. In some variations, the first tail is integrally formed with the load-bearing element. Alternatively or in combination, in some variations, the second tail is integrally formed with the load-bearing element. However, in further variations, the first tail is not integrally formed with the loadbearing element and the second tail is not integrally formed with the load-bearing element. For example, the first tail and the load-bearing element may in some variations be distinct pieces which in the mounted position are interconnected to each other. Similarly, the second tail and the load-bearing element may in some variations be distinct pieces which in the mounted position are interconnected to each other.

[0046] In some embodiments, the first tail comprises a locking section and a traction section. The locking section of the first tail may for example be arranged in longitudinal direction of the first tail between the load-bearing element and the traction section of the first tail. P28894PC00 14.1 1.2025

[0047] 1 1 / 41

[0048] Advantageously, the locking section of the first tail may be integrally formed with the load-bearing element.

[0049] Alternatively or in combination, these embodiments may also apply to the second tail. Thus, in some embodiments, the second tail comprises a locking section and a traction section. The locking section of the second tail may for example be arranged in longitudinal direction of the second tail between the load-bearing element and the traction section of the second tail. Advantageously, the locking section of the second tail may be integrally formed with the load-bearing element.

[0050] Preferably, the locking section of the first tail and the locking section of the second tail each comprise a core at least partially enveloped by a sheath. In at least some embodiments, the locking section of the first tail, the locking section of the second tail and the load-bearing element together form a sheath which at least partially envelopes a core. The sheath may for example comprise a textile, such as a woven textile.

[0051] In some variations, the first tail is interconnected with (e.g. attached to) a first interface of the load-bearing element arranged at the first end. Additionally or alternatiely, the second tail may be interconnected with (e.g. attached to) a second interface of the loadbearing element arranged at the second end. The first interface of the load-bearing element may e.g. be a first end section arranged at the first end, and the second interface of the load-bearing element may optionally e.g. be a second end section arranged at the second end.

[0052] Depending on the application, different interconnections may be chosen to interconnect the first tail with the first interface respectively the second tail with the second interface. For example, in some variations, the first tail may be interconnected with the first interface by a suture. Alternatively or in combination, the second tail may be interconnected P28894PC00 14.1 1.2025

[0053] 12 / 41 with the second interface by a suture. Optionally, the same suture may be used or two different sutures may be used. In some variations, the first tail itself may comprise a suture through which the first tail is interconnected with the first interface. Alternatively or in combination, in some variations, the second tail itself may comprise a suture through which the second tail is interconnected with the second interface.

[0054] In some variations, the first tail is a first filament, particularly a first suture. Alternatively or in combination, in some variations, the second tail is a second filament, particularly a second suture.

[0055] In some variations, the first tail is crimped to the first interface. Alternatively in in combination, the second tail may be crimped to the second interface.

[0056] Depending on the application, the first and second tail may optionally be integrally formed, or they may be two separate pieces. In some variations, the first tail and the second tail are sections of a single integrally formed tail, particularly a single integrally formed suture. Optionally, the single integrally formed tail may form a loop interconnecting the lock, the first interface and the second interface.

[0057] In some variations, the load-bearing element merges at the first end into the first tail by one or more of the following:

[0058] - an eyelet; and / or

[0059] - a suture; and / or a tape; and / or a Speedtrap Graft Preparation System by DePuy Synthes; and / or P28894PC00 14.1 1.2025

[0060] 13 / 41

[0061] - a Chinese finger-trap; and / or

[0062] - SpeedWhip technique by Arthrex; and / or

[0063] - FiberTag by Arthrex; and / or

[0064] - FiberTape by Arthrex; and / or - Tight Rope by Arthrex.

[0065] Alternatively or in combination, the variations listed in the previous sentence may also apply to the second tail. Thus, in some variations, the load-bearing element merges at the second end into the second tail by one or more of the following:

[0066] - an eyelet; and / or - a suture; and / or

[0067] - a tape; and / or

[0068] - a Speedtrap Graft Preparation System by DePuy Synthes; and / or

[0069] - a Chinese finger-trap; and / or

[0070] - SpeedWhip technique by Arthrex; and / or - FiberTag by Arthrex; and / or

[0071] FiberTape by Arthrex; and / or P28894PC00 14.1 1.2025

[0072] 14 / 41

[0073] - Tight Rope by Arthrex.

[0074] Preferably, in some variations, the first load-bearing element merges at the first end into the first tail by a tape, preferably by a FiberTape by Arthrex. Furthermore, in some variations, the second load-bearing element merges at the second end into the first tail by a tape, preferably by a FiberTape by Arthrex.

[0075] Depending on the application, different materials and shapes may be chosen for the first tail and for the second tail. It is understood that the materials and shapes may be chosen independently for the first tail and for the second tail. However, in some variations, the first tail and the second tail are made of the same material and may optionally have essentially the same shape.

[0076] In some variations, the first tail is essentially strap-like and may e.g. have a flat crosssection. Optionally, a circumference of the cross-section of the first tail may be rounded. Alternatively or in combination, in some variations, the second tail is essentially straplike and may e.g. have a flat cross-section. Optionally, a circumference of the crosssection of the second tail may be rounded.

[0077] In some variations, the first tail comprises or even consists of a suture, such as a first suture. Alternatively or in combination, the second tail may comprise or even consist of a suture. The suture of the first tail and the suture of the second tail may be identical or they may be distinct sutures. Using a single suture forming the first tail and the second tail can e.g. be advantageous to facilitate or enhance load transfer.

[0078] Depending on the application, the first tail and the second tail may have different tensile strengths. In some variations, the first tail has a higher tensile strength in longitudinal P28894PC00 14.1 1.2025

[0079] 15 / 41 direction than the load-bearing element. Alternatively or in combination, in some variations, the second tail has a higher tensile strength in longitudinal direction than the loadbearing element.

[0080] In some variations, the load-bearing element has a higher elasticity in longitudinal direction than the first tail and than the second tail. For example, in some variations, the loadbearing element has a lower modulus of elasticity in longitudinal direction than the first tail and than the second tail. In some variations the load-bearing element has an elasticity in longitudinal direction that is at least 30%, preferably at least 50%, more preferably at least 100%, in some cases even at least 200%, higher than the elasticity in longitudinal direction of the first tail and of the second tail. These variations can be advantageous to promote flattening of the cross-section of the load-bearing element in the region of the one or more load-bearing surfaces, which in turn promotes the other advantages discussed above, including enhanced load distribution and reduced risk of uncontrolled displacement of the fixator, e.g. in dorsal or anterior direction. As an example, when the load-bearing element has a higher elasticity than the first tail and the second tail, flexion of the spinal segment may lead to more flattening of the load-bearing element in the region of the one or more load-bearing surfaces than it would otherwise. For example, if the first tail and the second tail had a higher elasticity in longitudinal direction than the load-bearing element, the load associated with flexion of the spinal segment would primarily be absorbed by the first tail and the second tail, with less widening of the crosssection of the load-bearing element in the region of the one or more load-bearing surfaces.

[0081] The fixator usually comprises a lock. The lock is configured to maintain the load-bearing element in a pre-tension with respect to the neutral position of the spinal segment. P28894PC00 14.1 1.2025

[0082] 16 / 41

[0083] Depending on the application, different locks can be used. For example, the lock may in some variations be able to block the first tail and / or the second tail in order to maintain the pre-tension, but may also be used to apply a tension to the load-bearing element. In some variations, the lock is in an unlocked state displaceable along a length of the first tail and / or along a length of the second tail. In a locked state, displacement of the lock along the length of the first tail and / or along the length of the second tail may be blocked in at least one direction. It is understood that the term “and / or” in the previous two sentences means that the described functions may apply only to the first tail, or only to the second tail, or to the first tail and to the second tail. For example, in some variations, the lock is in an unlocked state displaceable along a length of the first tail and along a length of the second tail; and wherein in the locked state displacement of the lock along the length of the first tail is blocked in at least one direction; and wherein in the locked state displacement of the lock along the length of the second is blocked in at least one direction.

[0084] In further variations, the fixator comprises two or even more locks. For example, in some variations it is possible that a first lock is in an unlocked state of the first lock displaceable along a length of the first tail; and wherein in a locked state of the first lock displacement of the first lock along the length of the first tail is blocked in at least one direction. Optionally, a second lock may in an unlocked state of the second lock be displaceable along a length of the second tail; and wherein in a locked state of the second lock displacement of the second lock along the length of the second tail may be blocked in at least one direction.

[0085] By using a lock that is displaceable in an unlocked state and whose displacement is blocked in at least one direction in a locked state, the lock allows to easily apply a tension to the load-bearing element, e.g. by displacing the lock in a tensioning direction, where P28894PC00 14.1 1.2025

[0086] 17 / 41 displacement in an opposite loosening direction is blocked, thereby essentially preventing loosening of the tension after its application.

[0087] Depending on the application, the lock may be switchable between the unlocked state and the locked state. In some variations, however, the lock may be configured to be simultaneously in an unlocked state and in a locked state. For example, in some variations, the lock is displaceable along a length of the first tail (and / or along a length of the second tail) in a first longitudinal direction corresponding to a tensioning direction, and displacement of the lock along the length of the first tail (and / or along the length of the second tail) is blocked in an opposite second longitudinal direction corresponding to a loosening direction.

[0088] Depending on the application, different locks may be used. In some variations, the lock comprises a button, such as a self-locking button. For example, the button may be interconnected with the first tail and / or with the second tail such that a free end of the first tail and / or a free end of the second tail may be pulled to apply a tension to the load-bearing element, but where the first tail and / or the second tail blocks itself when the pull-force is removed, thereby preventing loss of the applied tension. In some variations, the button is an Arthrex TightRope button or an Arthrex TightRope II button.

[0089] In some variations, an operation length of the first tail is adjustable by pulling a free end of the first tail, thereby displacing the first tail with respect to the lock. Alternatively or in combination, in some variations, an operation length of the second tail is adjustable by pulling a free end of the second tail, thereby displacing the second tail with respect to the lock.

[0090] In some variations, the lock comprises a ratchet element. For example, the lock may comprise a ratchet element configured to block in the locked state displacement of the P28894PC00 14.1 1.2025

[0091] 18 / 41 lock along the length of the first tail and / or along the length of the second tail in the at least one direction.

[0092] In some variations, the lock comprises a clamp. For example, the clamp may comprise a first clamp portion and a second clamp portion movable with respect to the first clamp portion, wherein the first clamp portion and the second clamp portion are configured to clamp between them in the mounted position the first tail and the second tail. As an example, a locking section of the first tail may be configured to be clamped in the mounted position between the first clamp portion and the second clamp portion, and a locking section of the second tail may also be configured to be clamped in the mounted position between the first clamp portion and the second clamp portion.

[0093] The fixator usually comprises one or more load-bearing surfaces which are established by contact with another structure. Depending on the application, the fixator may comprise only a first load-bearing surface, or the fixator may additionally comprise a second loadbearing surface and possibly even more load-bearing surfaces. The load-bearing surfaces (i.e. the one or more load-bearing surfaces) are arranged in longitudinal direction between the first end and the second end of the load-bearing element. In some variations, the fixator comprises a second load-bearing surface configured for contacting in a mounted position the second vertebra and for forming in the mounted position a semiloop around the second vertebra. Typically, the one or more load-bearing surfaces are arranged are interspaced from each other in longitudinal direction, e.g. interspaced by one or more regions that are free of load-bearing surfaces.

[0094] Depending on the application, the number of load-bearing surfaces may be chosen in accordance with the intended use of the fixator. For example, in some variations, the fixator comprises two load-bearing surfaces configured for contacting the spinous processes of the first and second vertebra. In some variations, the first load-bearing surface P28894PC00 14.1 1.2025

[0095] 19 / 41 and the second load-bearing surface are configured to be arranged in the mounted position on opposite sides of the spinous processes of the first and second vertebra. For example, in some variations, the first load-bearing surface is configured to be arranged in the mounted position on a cranial surface of the spinous process of a cranial vertebra. Alternatively or in combination, in some variations, the second load-bearing surface is configured to be arranged in the mounted position on a caudal surface of the spinous process of a caudal vertebra.

[0096] In some variations, the fixator comprises a second load-bearing surface configured for contacting in the mounted position the second vertebra, wherein the fixator forms in the mounted position a closed loop encircling the first vertebra and the second vertebra, particularly a spinous process of the first vertebra and a spinous process of the second vertebra. One advantage of these variations is that they allow for effective and elastic restriction of flexion while only exerting a minimal to negligible influence on other directions of motion. In particular, while flexion is restricted, extension and other directions of motion may be essentially undisturbed.

[0097] In some variations, for example in some of the variations described in the previous paragraph, the lock is configured for holding in the mounted position the first tail and the second tail under tension.

[0098] Depending on the application, the fixator may form a single closed loop encircling the first vertebra and the second vertebra, or the fixator may form a closed structure formed by two loops each encircling the first vertebra and the second vertebra. The closed structure formed by two loops may in particular be formed by encircling the first and second vertebra twice with the fixator, thereby forming two loops, each of which encircle the first and second vertebra. Some variations for forming such a closed structure are described P28894PC00 14.11.2025

[0099] 20 / 41 in patent application US 18 / 777 / 791 , which is incorporated herein by reference in its entirety. Should there be any contradiction between the present disclosure and the terminology used in US 18 / 777 / 791 or the variations described in US 18 / 777 / 791 or any other piece of the disclose of US 18 / 777 / 791 , the terminology, variations and specifications of the present application shall prevail over US 18 / 777 / 791.

[0100] Depending on the application, different materials may be chosen for the load-bearing element. In some variations, the load-bearing element consists of a material having a non-linear stress-strain curve. For example, the stress-strain curve may comprise a first shallow region and, subsequently, a second steeper region. It is understood that the first shallow region relates to lower strain levels than the second steeper region.

[0101] In some variations, the load-bearing element comprises or is made of a fibrous material. For example, the fibrous material may comprise a plurality of fibers extending in longitudinal direction. Depending on the application, the fibers of the plurality of fibers may or may not be aligned. In some variations, the alignment may also change upon application of a tensile force. In some variations, in an untensioned state of the load-bearing element a plurality of fibers forming the fibrous material are unaligned in the longitudinal direction, wherein the plurality of fibers increasingly align themselves in the longitudinal direction with an increase in a tensile force applied to the load-bearing element in the longitudinal direction. These variations may for example be advantageous to minimize the risk of displacement of the fixator, especially displacement in dorsal or anterior direction. For example, in these variations, flexion beyond the neutral position may initially lead primarily to alignment of the fibers. If the first load-bearing surface of the load-bearing element rests on the first vertebra, e.g. on the spinous process of the first vertebra, then increasing alignment of the fibers may enhance the grip between the first load-bearing surface P28894PC00 14.11.2025

[0102] 21 / 41 and the spinous process of the first vertebra, thereby minimizing the risk of dorsal displacement. This may apply in particular to the displacement on the spinous process of a dorsal vertebra.

[0103] In some variations, the load-bearing element comprises a tendon, a ligament, an allograft, an autograft or a xenograft. Preferably, the load-bearing element comprises an allograft. In some variations, the load-bearing element may additionally comprise one or more other materials or components, e.g. to form a hybrid material. However, in some variations, the load-bearing element essentially consists of a tendon, a ligament, an allograft, an autograft or a xenograft.

[0104] In some variations, the load-bearing element comprises a synthetic material, such as a braid and / or weave and / or stitched material and / or felt. The synthetic material may e.g. be or comprise a tape. In some variations, the synthetic material is a non-metallic cerclage. Depending on the application, the non-metallic cerclage may be braided or woven from a polyblend of ultra-high molecular weight polyethylene and polyester materials. In some variations, the non-metallic cerclage is made from pure polyethylene terephthalate (PET). Additionally or alternatively, the non-metallic cerclage may be a flat braided suture or a woven suture. In some variations, the load-bearing element is made of a woven structure or a tape or a synthetic ligament.

[0105] In some variations, the load-bearing element comprises or is made of a hybrid material comprising a synthetic component and a natural component. For example, the natural component can be a tendon, a ligament, an allograft, an autograft or a xenograft, preferably an allograft. Alternatively or in combination, the synthetic material can for example be a braid and / or weave and / or stitched material and / or felt. P28894PC00 14.11.2025

[0106] 22 / 41

[0107] Depending on the application, the components of the hybrid material may have different arrangements with respect to each other. For example, the synthetic component and the ligament (or tendon) component may extend essentially parallel and adjacent to each other. In some variations, one of the materials forms a sheath and circumferentially encompasses at least a longitudinal section of the other component. As an example, the synthetic component may form a sheath circumferentially encompassing at least a longitudinal section of the natural component. These variations may e.g. be labelled as an “around / inside arrangement”.

[0108] In some variations, the load-bearing element comprises a core at least partially enveloped by a sheath. For example, the core may consist of the natural component (e.g. a graft such as an allograft) and the sheath may consist of the synthetic component. Depending on the application, the sheath may envelope the core along at least a longitudinal section of the load-bearing element. In some variations, the sheath extends beyond the entire length in longitudinal direction of the core. In other words, in some variations, the core may be fully encompassed by the sheath in longitudinal direction. Depending on the application, the core may have different lengths in longitudinal direction. For example, in some variations, the core may be arranged in longitudinal direction in the region of the one or more load-bearing surfaces. In some embodiments, the core comprises a first core section arranged in the region of the first load-bearing surface and optionally a second core section arranged in the region of the second load-bearing surface. In some variations, the core only extends along the length of the one or more load-bearing surfaces. For example, the core could be used for selective reinforcement or dampening in these regions. In further variations, the core extends in longitudinal direction beyond the one or more load-bearing surfaces. For example, in some variations, the core extends along at least 50%, such as at least 75%, e.g. at least 85%, of the length in longitudinal direction of sheath. In some variations, the ends of the core in longitudinal direction may be arranged within the sheath. However, in some variations, the core may comprise at P28894PC00 14.11.2025

[0109] 23 / 41 least one end in longitudinal direction that extends in longitudinal direction beyond the sheath.

[0110] In some variations, the components of the hybrid material are arranged in a “side-by- side” configuration. For example, in some variations, the synthetic component and the natural component (which may e.g. be made of a fibrous material) component extend parallel and next to each other in longitudinal direction. In some variations, the synthetic component and the natural component contact each other in longitudinal direction, such that a longitudinal section of an outer surface of the synthetic component and a longitudinal section of an outer surface of the natural component form together an outer surface of the hybrid material. In some variations, the synthetic component and the natural component are attached to each other, preferably at different longitudinal positions. Preferably, the synthetic component and the natural component are not displaceable with respect to each other in longitudinal direction.

[0111] Depending on the application, if hybrid materials are used for the load-bearing element, the load may be distributed differently between the components of the hybrid material. For example, in some variations, the load is distributed essentially evenly between the natural component and the synthetic component of the load-bearing element. This may in particular be the case if the natural and the synthetic components are attached to each other and / or if the natural and synthetic components both extend across the entire length in longitudinal direction of the load-bearing element. However, it is also possible to provide a load-bearing element in which the load is essentially borne by either the natural component or the synthetic component. For example, in some variations, the natural component may form a core at least partially enveloped by a sheath formed by the synthetic component, wherein optionally the core may even be displaceable within the sheath. In these variations, the load may essentially be borne exclusively by the synthetic component forming the sheath. P28894PC00 14.11.2025

[0112] 24 / 41

[0113] For optimal results, there should be during loading and unloading as little displacement of the fixator with respect to the spinous processes in the area of the first load bearing surface, respectively second load bearing surface, as possible. This can be achieved in that the first section and the second section the fixator comprise in the mounted position and after a certain operation time a similar elasticity, respectively spring rate (force per displacement [N / mm]) although they consist of different elements when compared to each other. It may be that this does not occur at the very beginning after implementation as some setting process may occur, especially with respect to the first and the second interface. Therefore some initial displacements in connection may occur. For better understanding, in Figure 11 as described hereinafter, aspects with respect of the mechanical behavior are explained in accordance with mechanical substitute model. In particular, the fixator when forming a semi-loop around the first vertebrae a first section of the fixator laterally arranged opposite to a second section of the fixator with respect to the semi-loop have with respect to their overall length an equivalent spring rate such applied load is balanced and no unwanted relative displacement occurs with respect to the first vertebrae over time.

[0114] BRIEF DESCRIPTION OF THE DRAWINGS

[0115] The disclosure described herein will be more fully understood from the detailed description given herein below and the accompanying drawings, which should not be considered limiting to the disclosure described in the appended claims. The drawings show:

[0116] Fig. 1 shows a first variation of a fixator 1 in a perspective view arranged in a mounted position;

[0117] Fig. 2 shows a interfaces 43; P28894PC00 14.11.2025

[0118] 25 / 41

[0119] Fig. 3 shows a second interface 44;

[0120] Fig. 4 shows a first possible arrangement of a fixator 1 at a spine 15;

[0121] Fig. 5 shows a second possible arrangement of a fixator 1 at a spine 15;

[0122] Fig. 6 shows a fixator 1 interconnecting a first and a second spinous process 11 .

[0123] Fig. 7 shows an embodiment of a fixator 1 comprising a load-bearing element 4 made of a hybrid material;

[0124] Fig. 8 shows a further embodiment of a fixator 1 comprising a load-bearing element 4 made of a hybrid material;

[0125] Fig. 9 shows a further embodiment of a fixator 1 comprising a load-bearing element 4 made of a hybrid material;

[0126] Fig. 10 shows an embodiment of a load-bearing element 4 formed by a graft in which the two ends of the graft are folded to form semi-loops defining the first and second end of the load-bearing element;

[0127] Fig. 11 shows a fixator in different conditions;

[0128] Fig. 12 shows a first diagram with analogues spring behavior;

[0129] Fig. 13 shows a further embodiment of a fixator 1 of the present disclosure. P28894PC00 14.11.2025

[0130] 26 / 41

[0131] DESCRIPTION OF THE VARIATIONS

[0132] Reference will now be made in detail to certain variations, examples of which are illustrated in the accompanying drawings, in which some, but not all features are shown. Indeed, variations disclosed herein may be embodied in many different forms and should not be construed as limited to the variations set forth herein; rather, these variations are provided so that this disclosure will satisfy applicable legal requirements. Whenever possible, like reference numbers will be used to refer to like components or parts. Should a reference sign be missing in one drawing reference is made to the other drawings.

[0133] Figure 1 shows a first variation of a fixator 1 in a perspective view looped in a single loop around the spinous processes of a first vertebra 2 and a second vertebra 3 interconnecting the two vertebra 2, 3 in a flexible manner. Figure 2 and Figure 3 show possible interfaces 43, 44 arranged at a first end respectively a second end 41 , 42 of a loadbearing element 4. Figure 4 and Figure 5 show a first and a second possible arrangement of a load-bearing element 4 at a spine 15. Figure 6 shows in a schematical manner a fixator 1 according to the present disclosure interconnecting a first and a second spinous process 1 1 . Figure 7 through Figure 9 show embodiments of a fixator 1 comprising a load-bearing element 4 made of a hybrid material. Figure 10 show an embodiment of a load-bearing element 4 formed by a graft in which the two ends of the graft are folded to form semi-loops defining the first and second end of the load-bearing element. Figure 11 shows a fixator 1 in different conditions. Figure 12 shows a diagram with analogues spring behavior.

[0134] Figure 1 through Figure 6 and Figure 11 show different variations and arrangements of a fixator 1 according to the present disclosure for elastically restricting flexion of a spinal segment comprising a first vertebra 2 and a second vertebra 3. The fixator 1 usually comprises a load-bearing element 4 extending in a longitudinal direction from a first end 41 to a second end 42. The load-bearing element 4 may comprise one or more load- P28894PC00 14.11.2025

[0135] 27 / 41 bearing surfaces 5, 6 arranged in longitudinal direction between the first end 41 and the second end 42.

[0136] As visible in the variations according to Figure 1 , Figure 6 and Figure 11 , a first loadbearing surface 5, respectively a second load bearing surface 6, is configured for contacting in a mounted position the first vertebra 2, respectively the second vertebra 3, for forming a semi-loop 7 as described hereinabove in the general specification around the first vertebra 2, respectively the second vertebra 3. The load-bearing element 4 merges at the first end 41 into a first tail 8 and at the second end 41 into a second tail 9. Depending on the field of application, different ways of merging are possible. The fixator 1 may further comprises at least one lock 10 interconnected in the mounted position to the first tail 8 and / or the second tail 9 to maintain the load-bearing element 4 in a pre-tension with respect to a neutral position of the spinal segments involved, thereby providing an elastic resistance to flexion beyond the neutral position. Usually the lock 10 is in an unlocked (open) state displaceable along a length of the first tail 8 and / or along a length of the second tail 9. In a locked (closed) state a displacement of the lock 10 along the length of the first tail 8 and / or along the length of the second tail 9 is blocked in at least one direction.

[0137] In difference to the prior art, the load-bearing element 4 preferably is in the region of the first load-bearing surface 5 essentially strap-like and preferably has a deformable crosssection which in the mounted position under the forces applied may flatten extending in lateral direction when in contact with the a surface of the first and / or the second vertebra 2, 3 in the region of the first load-bearing surface 5, respectively the second load bearing surface 6, such that the load is well distributed in lateral direction to the contour of the interacting surface of the vertebrae 2, 3. As a result, the cross-section of the load-bearing element 4 in the region of the one or more load-bearing surfaces 5, 6 may be in lateral direction wider than the cross-section of the load-bearing element 4 in a region outside P28894PC00 14.11.2025

[0138] 28 / 41 the one or more load-bearing surfaces. Good results are achieved when the first tail 8 is interconnected with a first interface 43 of the load-bearing element 4 arranged at the first end 41 and wherein the second tail 9 is interconnected with a second interface 44 of the load-bearing element 4 arranged at the second end 41 .

[0139] As visible in the shown variations, good results can be achieved when the first loadbearing element 4 merges at the first end 41 and / or the second end 41 into the first tail 8 respectively the second tail 9 by an eyelet 17. Depending on the field of application other transitions are possible which may include but are not limited to an eyelet and / or a suture and / or a tape and / or a Speedtrap Graft Preparation System by DePuy Synthes and / or a self-tightening Chinese finger-trap and / or SpeedWhip technique by Arthrex and / or FiberTag by Arthrex; and / or FiberTape by Arthrex; and / or Tight Rope by Arthrex. The lock 10 may be incorporated as a button, particularly a self-locking button, more particularly Arthrex TightRope or Arthrex TightRope II. If appropriate, the lock 10 may comprise a ratchet element configured to block in the locked state displacement of the lock 10 along the length of the first tail 8 and / or along the length of the second tail 9 in at least one direction. As shown in certain drawings, the fixator 1 may further comprise a second load-bearing surface 6 configured for contacting in the mounted position the second vertebra 3, wherein the fixator 1 forms in the mounted position at least one closed loop encircling the first vertebra 2 and the second vertebra 3, particularly a spinous process 1 1 of the first vertebra 2 and a spinous process of the second vertebra 3.

[0140] For optimal load distribution, the shape and properties of the cross-section of the loadbearing element 4 may vary along the longitudinal direction. Depending on the field of application, the load-bearing element 4 may comprise but is not limited to at least one of the following selection: a tendon, a ligament, an allograft, an autograft, a xenograft or a combination thereof. As schematically indicated in Figure 1 the load-bearing element 4 may at least partially comprise a fibrous material 12. As schematically indicated in Figure P28894PC00 14.11.2025

[0141] 29 / 41

[0142] 3, the load-bearing element 4 may comprise a core which is at least partially enveloped by a sheath 14. The sheath 14 may for example be made of a synthetic material, and the core may for example be made of a natural component, e.g. a graft such as an allograft. In a preferred variation, the first tail 8 is a first filament, particularly a first suture, and / or wherein the second tail 9 is a second filament, particularly a second suture. The first and the second suture may be interconnected to each other or merge into each other.

[0143] Figures 7 through 9 show three different embodiments of a fixator 1 having a loadbearing element 4 that is formed of a hybrid material comprising a natural component (e.g. a tendon or a graft) and a synthetic component. In the embodiments shown in Figures 7 and 8, the two components are arranged coaxially with respect to each other, with one of the two components forming a core 13 arranged inside a surrounding sheath 14 formed by the other component. In the illustrated embodiments, the core 13 is formed by the natural component and the sheath 14 is formed by the synthetic component. In the embodiment shown in Figure 7, the core 13 is arranged primarily in the region of the first load-bearing surface 5 and of the second load-bearing surface 6 of the fixator 3. In the embodiment shown in Figure 8, the core 13 extends along a larger segment of the sheath 14 in longitudinal direction.

[0144] In the embodiment shown in Figure 9, the load-bearing element 4 is also formed by a hybrid material comprising a natural component and a synthetic component. However, unlike in Figures 7 and 8, the two components are not arranged in a core-sheath arrangement in Figure 9 but rather in a side-by-side configuration. For example, the embodiment shown in Figure 9 could be realized by bonding a synthetic tape with an allograft over essentially the entire length of the allograft. P28894PC00 14.11.2025

[0145] 30 / 41

[0146] The different relative lengths and arrangements of the natural and synthetic component in a hybrid material can be chosen to influence the mechanical properties, especially the tensile properties, of the fixator 1 . For example, it may be preferable to arrange a tendon or graft with a deformable cross-section in the region of the load-bearing surfaces 5, 6 in order to distribute the load across a larger surface. Depending on the application, it can be desirable to extend the graft or tendon, as well as the synthetic component across essentially the entire length of the load-bearing element in order to distribute the load to both the natural and the synthetic component, as is the case e.g. in the embodiment shown in Figure 9. By contrast, in other applications, it may be desirable to bear the load essentially entirely by the synthetic component, as is the case e.g. in the embodiment shown in Figure 7, and to employ the natural component specifically for the purpose of load-distribution in the region of the load-bearing surfaces.

[0147] Figure 10 shows an embodiment of a load-bearing element 4 formed by a graft. In some embodiments, a single graft may be used to form the load-bearing element 4 and the two ends of the graft may correspond to the ends of the load-bearing element. However, in the embodiment illustrated in Figure 10, the two ends of the graft are each folded back onto the graft, thereby forming two semi-loops corresponding to the first end 41 of the graft and the second end 42 of the graft in longitudinal direction. In other words, in the illustrated embodiment, although the load-bearing element 4 is formed by a graft, the two ends in longitudinal direction of the graft do not correspond to the two ends 41 , 42 of the load-bearing element in longitudinal direction. One advantage of the embodiment illustrated in Figure 10 is that the tensile strength of the load-bearing element 4 can be increased by reducing the risk of tear or other damage to the graft under tension. More complicated graft preparation systems can optionally be used to further increase the tensile strength, potentially involving multiple folds being formed from the graft. A further advantage of the illustrated embodiment is that the first tail 8 and the second tail 9 can each be displaced with respect to the load-bearing element 4. This can be beneficial P28894PC00 14.11.2025

[0148] 31 / 41 especially during tensioning because it allows e.g. the first tail 8 to gradually slide or slip with respect to end 41 , thereby avoiding any slack.

[0149] Figure 11 shows several aspects of a fixator 1 according to the present disclosure and as described hereinabove in a schematic and simplified manner. Figure 11 contains three drawing sections: Drawing section a), drawing section b) and drawing section c). The fixator 1 is shown in drawing section a) in an installed position at a first load level in a pretensioned state and in a balanced manner. In drawing section b) the fixator 1 is - compared to drawing section a) - shown in a state under higher tension load (force F) than in drawing section a). This case may occur when the first and the spinous process 1 1 of the second vertebrae 2, 3 around which the fixator is wrapped, are moved apart from each other.

[0150] The deformation resulting from the force F is schematically indicated by arrow AL between drawing section a) and drawing section b). The fixator 1 is shown in an implanted state interconnecting the first vertebrae 2 and the second vertebrae 3 as described herein above. As it can be seen in Figure 11a and Figure 11 b, the fixator 1 comprises a first section 18 (left hand side) and a second section 19 (right hand side) which consist of different elements which have a different setup with respect to each other. While the first section 18 consists of a single element in form of a uniform strap forming the main part of the load bearing element 4 (e.g. a tendon), the second section 19 (right hand side) equivalent to the first section 18 (left hand side) essentially consists of the first interface 43 and the second interface 44 merging into the respective tails 8, 9 which are then in the shown variation directly interconnected to each other by the lock 10 as schematically indicated (different variations are possible). For optimal results, there should be during loading and unloading as little displacement of the fixator 1 with respect to the spinous processes 11 in the area of the first load bearing surface 5, respectively second load bearing surface 6, as possible. This can be achieved in that the first section 18 and P28894PC00 14.11.2025

[0151] 32 / 41 the second section 19 of the fixator 1 comprise in the mounted position and after a certain operation time a similar elasticity (force per displacement [N / mm]) although they consist of different elements left and right. It may be that this does not occur at the very beginning as some setting process may occur, especially with respect to the first and the second interface 43, 44. Therefore some initial displacements in connection may occur. When now turning to a non-limiting example: E.g. at a load of F=1000 N there should preferably be less than 0.5 mm relative displacement (indicated by arrows 8 / 2 in drawing section b)) per spinous process 11 . To achieve this, the stiffness, i.e. overall spring rate, of the first section 18 and the second section 19 of the fixator 1 shown in the drawing Figure 11 should not differ significantly, in other words they should act similar with respect to each other within certain boundaries (see Figure 12). Drawing section c) of Figure 11 schematically shows a simplified mechanical model which shall indicate the left and the right side of the fixator 1 as shown in drawing section b) above of drawing section c). When e.g. forming a semi-loop 7 around the first vertebrae 2, a first section 18 of the fixator 1 arranged opposite to a second section 19 of the fixator 1 have with respect to their overall length an equivalent stiffness such that applied load F is balanced and no unwanted relative displacement occurs. 6 = Displacement, k = Spring Rate, E = Young Modulus, A = Area, L = Length.)

[0152] When seen from behind in a plane view as shown in Figure 11 , the left, as well as the right side should have a combination of spring constants which is comparable to each other within a certain window. In particular, the lower the spring constant kA of the left side (A) is, the less ks may deviate (example (low): kA= 200 N / mm, kB max= 250 N / mm, P28894PC00 14.11.2025

[0153] 33 / 41 kB min= 167 N / mm). The greater the spring constant kA of the left side (A), the more kB is allowed to deviate. In particular, with high stiffnesses it becomes irrelevant (example (high): kA= 1000 N / mm, kBmax= >10,000 N / mm, kB min= 500 N / mm) The spring constant depends on the modulus of elasticity, the cross sectional area and the length. The spring constant depends on the anatomy. (Average is L=~50mm). The spring constant kBis a combination of the load bearing material and the lock (irreversible elongation excluded). Figure 12 schematically indicates in a diagram according to an example how much the spring constants may deviate from each other to prevent negative wandering or displacement of the load bearing element 4 relative to the spinous processes 1 1 .

[0154] Figures 13A and 13B illustrate a further embodiment of the fixator of the present disclosure. Fig. 13A illustrates the fixator in a cross-sectional view and before mounting, whereas Fig. 13B illustrates the fixator in a mounted position in an application in which the fixator fixates the spinous processes of two adjacent vertebrae 2, 3 with respect to each other.

[0155] As shown in Fig. 13A, the fixator 1 comprises a load-bearing element 4 which at a first end merges into a first tail 8, and which at a second end merges into a second tail 9. In the illustrated embodiment, the first tail 8 and the second tail 9 are each composed of two different sections, namely a locking section 81 , 91 and a traction section 82, 92. The locking section 81 , 91 of each tail is configured to be interconnected in the mounted position to a lock 10, as illustrated in Fig. 13B. The traction section 82, 92 of each tail acts as a handle for tensioning the load-bearing element during mounting.

[0156] As shown in Fig. 13A, the locking section 81 of the first tail 8 is arranged in longitudinal direction of the first tail 8 between the load-bearing element 4 and the traction section 82 P28894PC00 14.11.2025

[0157] 34 / 41 of the first tail 8. Similarly, the locking section 91 of the second tail 9 is arranged in longitudinal direction of the second tail 9 between the load-bearing element 4 and the traction section 92 of the second tail 9.

[0158] Furthermore, in the illustrated embodiment, the first tail 8, the load-bearing element 4 and the second tail 9 are integrally formed. More specifically, the load-bearing element 4 has essentially the same construction and is made of essentially the same material as the locking sections 81 , 91 of the first and second tail 8, 9. The traction sections 82, 92 of the first and second tail 8, 9, by contrast, have a slightly different construction, as illustrated in Fig. 13A.

[0159] In the illustrated embodiment, the implant is formed of a woven textile which has two outer, more narrow sections, and a central, widened section. In the central, widened section, the woven textile is filled with a core made of a soft material. The soft core filling leads to a deformable cross-section.

[0160] As illustrated in Fig. 13A, the central section with the soft core forms the locking section 81 of the first tail 8, the load-bearing element 4, as well as the locking section 91 of the second tail 9. The deformable cross-section imparted by the soft core is advantageous for the load-bearing element 4 because it leads to widening and therefore increased load distribution in the regions of the first load-bearing surface 5 and the second load-bearing surface 6 where the load-bearing element 4 contacts the first and second vertebra 3, 4.

[0161] Additionally, depending on the application, the deformable cross-section can also be advantageous for the locking sections 81 , 91 of the first and second tails 8, 9. For example, when a clamp is used as lock 10 (i.e. where the locking section 81 of the first lock 8 and the locking section 91 of the second lock 9 are clamped inside the clamp), then the de- P28894PC00 14.11.2025

[0162] 35 / 41 formable cross-section can lead to increased deformation upon clamping, which ultimately leads to friction-fit that additionally secures the locking sections 81 , 91 inside the clamp.

[0163] Fig. 13A also illustrates that in this embodiment, the central section with the soft core is surrounded on either side by a transitional section with a tapering cross section, which ultimately merges into a narrower section. The narrower section may for example be devoid of a core. On either side, the respective transitional section and the subsequent narrower section together form the traction section 82 of the first tail 8, respectively the traction section 92 of the second tail 9. The traction sections 82, 92 may for example be connected to a tensioning instrument during mounting, which allows the load-bearing element 4 to be tensioned. After mounting, the traction sections 82, 92 may optionally be removed (e.g. by cutting them off) or they may be left inside the body of the patient.

[0164] P28894PC00 14.11.2025

[0165] 36 / 41

[0166] LIST OF DESIGNATIONS

[0167] 1 Fixator (implant) 9 Second tail

[0168] 2 First vertebra 91 Locking section of second tail

[0169] 3 Second vertebra 92 Traction section of second tail

[0170] 4 Load-bearing element 10 Lock

[0171] 41 First end 11 Spinous process

[0172] 42 Second end 12 Fibrous material

[0173] 43 First interface 13 Core (load bearing element)

[0174] 44 Second interface 14 Sheath (load bearing element)

[0175] 5 First load-bearing surface (fix15 Spine ator) 16 Bore (spinous process)

[0176] 6 Second load-bearing surface 17 Eyelet (fixator) 18 First section (fixator)

[0177] 7 Semi-loop 19 Second section (fixator)

[0178] 8 First tail

[0179] 81 Locking section of first tail

[0180] 82 T raction section of first tail

Claims

1. P28894PC00 14.11.202537 / 41PATENT CLAIMS1. Fixator (1 ) for elastically restricting flexion of a spinal segment comprising a first vertebra (2) and a second vertebra (3), the fixator (1 ) comprising: a. a load-bearing element (4) extending in a longitudinal direction from a first end (41 ) to a second end (42), the load-bearing element (4) comprising one or more load-bearing surfaces (5, 6) arranged in longitudinal direction between the first end (41 ) and the second end (42), wherein a first loadbearing surface (5) is configured for contacting in a mounted position the first vertebra (2) and for forming in the mounted position a semi-loop (7) around the first vertebra (2); b. wherein the load-bearing element (4) merges at the first end (41 ) into a first tail (8) and at the second end (41 ) into a second tail (9); c. wherein the fixator (1 ) further comprises at least one lock (10) interconnected in the mounted position to the first tail (8) and / or the second tail (9) to maintain the load-bearing element (4) in a pre-tension with respect to a neutral position of the spinal segment, thereby providing an elastic resistance to flexion beyond the neutral position.

2. Fixator (1 ) according to claim 1 , wherein the lock (10) is in an unlocked state displaceable along a length of the first tail (8) and / or along a length of the second tail (9); and wherein in a locked state displacement of the lock (10) along the length of the first tail (8) and / or along the length of the second tail (9) is blocked in at least one direction.P28894PC00 14.11.202538 / 413. Fixator (1 ) according to any one of the previous claims, wherein the load-bearing element (4) in the region of the first load-bearing surface (5) is essentially straplike and has a deformable cross-section which in the mounted position flattens in lateral direction when in contact with the first vertebra (2) in the region of the first load-bearing surface (5), such that the load is distributed in lateral direction.

4. Fixator (1 ) according to any one of the previous claims, wherein in the mounted position the cross-section of the load-bearing element (4) in the region of the one or more load-bearing surfaces (5, 6) is wider in lateral direction than the crosssection of the load-bearing element (4) in a region outside the one or more loadbearing surfaces.

5. Fixator (1 ) according to any one of the previous claims, wherein the first tail (8) is interconnected with a first interface (43) of the load-bearing element (4) arranged at the first end (41 ); and wherein the second tail (9) is interconnected with a second interface (44) of the load-bearing element (4) arranged at the second end (41 ).

6. Fixator (1 ) according to any one of the previous claims, wherein the load-bearing element (4) merges at the first end (41 ) and / or the second end (41 ) into the first tail (8) respectively the second tail (9) by: a. an eyelet; and / or b. a suture; and / or c. a tape; and / or d. a Speedtrap Graft Preparation System by DePuy Synthes; and / orP28894PC00 14.11.202539 / 41 e. a Chinese finger-trap; and / or f. SpeedWhip technique by Arthrex; and / or g. FiberTag by Arthrex; and / or h. FiberTape by Arthrex; and / or i. Tight Rope by Arthrex.

7. Fixator (1 ) according to any one of the previous claims, wherein the lock (10) comprises a button, particularly a self-locking button, more particularly Arthrex Tight- Rope or Arthrex TightRope II.

8. Fixator (1 ) according to any one of the previous claims, wherein the lock (10) comprises a ratchet element configured to block in the locked state displacement of the lock (10) along the length of the first tail (8) and / or along the length of the second tail (9) in at least one direction.

9. Fixator (1 ) according to any one of the previous claims, wherein the fixator (1 ) comprises a second load-bearing surface (6) configured for contacting in the mounted position the second vertebra (3), wherein the fixator (1 ) forms in the mounted position a closed loop encircling the first vertebra (2) and the second vertebra (3), particularly a spinous process of the first vertebra (2) and a spinous process of the second vertebra (3).

10. Fixator (1 ) according to any one of the previous claims, wherein when forming a semi-loop (7) around the first vertebrae (2), a first section (18) of the fixator (1 ) laterally arranged opposite to a second section (19) of the fixator (1 ) with respectP28894PC00 14.1 1.202540 / 41 to the semi-loop (7) have with respect to their overall length an equivalent spring rate such applied load (F) is balanced and no unwanted relative displacement occurs with respect to the first vertebrae (2).1 1 . Fixator (1 ) according to any one of the previous claims, wherein the load-bearing element (4) has a lower elasticity in longitudinal direction than in lateral direction.

12. Fixator (1 ) according to any one of the previous claims, wherein the shape of the cross-section of the load-bearing element (4) varies along the longitudinal direction.

13. Fixator (1 ) according to any one of the previous claims, wherein the first tail (8) is integrally formed with the load-bearing element (4); and / or wherein the second tail (9) is integrally formed with the load-bearing element (4).

14. Fixator (1 ) according to any one of the previous claims, wherein the load-bearing element (4) comprises a tendon, a ligament, an allograft, an autograft or a xenograft.

15. Fixator (1 ) according to any one of the previous claims, wherein the load-bearing element (4) comprises a fibrous material.

16. Fixator (1 ) according to any one of the previous claims, wherein the load-bearing element (4) comprises a core at least partially enveloped by a sheath.

17. Fixator (1 ) according to any one of the previous claims, wherein the first tail (8) is a first filament, particularly a first suture, and / or wherein the second tail (9) is a second filament, particularly a second suture.

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