Orthopaedic device, method of manufacturing

Abstract

The present disclosure relates to an orthopaedic device, comprising a first device body comprising a first engagement surface configured to engage against a first target surface of a joint of a patient. The first device body comprises a flexible material configured to allow the first engagement surface to deform and thereby conform with the first target surface. The first engagement surface comprises a microtexture configured to allow movement of cells across the engagement surface by movement of the cells between protruding portions of the microtexture when the first engagement surface is engaged against the first target surface.

Description

[0001] ORTHOPAEDIC DEVICE, METHOD OF MANUFACTURING

[0002] The present disclosure relates to an orthopaedic device and method for manufacturing the same.

[0003] Orthopaedic devices implanted in a joint can be used to treat joint dysfunction, such as may arise through damage to the cartilage surfaces of a joint, for example due to arthritis. Current orthopaedic devices often require invasive surgery to use, sometimes involving replacement of all or part of a patient’s own joint surface. These devices also may not allow a full range of motion for the treated joint.

[0004] It is an object of the present invention to at least partially address one or more of the issues mentioned above, or other issues.

[0005] According to an aspect of the disclosure, there is provided an orthopaedic device, comprising a first device body comprising a first engagement surface configured to engage against a first target surface of a joint of a patient, wherein the first device body comprises a flexible material configured to allow the first engagement surface to deform and thereby conform with the first target surface; and the first engagement surface comprises a microtexture configured to allow movement of cells across the engagement surface by movement of the cells between protruding portions of the microtexture when the first engagement surface is engaged against the first target surface.

[0006] An orthopaedic device provided with the microtexture facilitates, the migration of cells, which may for example be stem cells and / or cartilage cells, from healthy areas to damaged areas of the joint, promoting healing of the patient’s own joint surface. This may be facilitated by the movement of synovial fluid at the interface between the engagement and target surfaces. The healing may reduce pain and improve joint function, and may allow the joint to heal to a point where the device can be removed and full joint function is restored. The microtexture also increases friction between the engagement surface of the device and the target surface, thereby improving stability and / or reducing the need for, or demands on, other fixture mechanisms.

[0007] Optionally, the microtexture comprises a repeating pattern of the protruding portions and recessed portions between the protruding portions, wherein an average separation between the protruding portions in at least a portion of the microtexture is in the range of about 50 to 500 pm and / or an average protruding height in at least a portion of the microtexture is in the range of about 50 to 2000 pm.

[0008] The dimensions of the protrusions between the recessed portions in the microtextured area allows for the cells to easily pass through the recessed portions to damaged areas of the joint. This improves the movement of the stem cells to these areas and promotes healing of damaged areas in the joint.

[0009] Optionally, the recessed portions define a plurality of grooves, and the plurality of grooves is arranged in a groove pattern, the groove pattern comprising an interconnected network of grooves.

[0010] An interconnected network of grooves further improves migration of the cells by allowing the cells to move in multiple directions across the articular surface of the joint in contact with the device.

[0011] According to an aspect of the disclosure, there is provided an orthopaedic device, comprising a first device body comprising a first engagement surface configured to engage against a first target surface of a joint of a patient, wherein the first device body comprises a closed loop of flexible material configured to allow the first engagement surface to deform and thereby conform with the first target surface; the closed loop defines an axis passing through the closed loop and two axially opposed openings; and the first engagement surface is a radially outward facing portion of the closed loop of flexible material.

[0012] Optionally, opposite radially inward facing portions of the closed loop of flexible material are configured to be slidably engaged with each other when the first device body is implanted in the joint of the patient, the slidable engagement being such that, during flexing of the joint, relative movement between the first engagement surface and the first target surface is substantially zero or at least less than relative movement between the slidably engaged inward facing portions..

[0013] The slidable engagement of the inner surfaces provides low friction in the direction of motion perpendicular to the axis between the axially opposed openings. This enables little to no relative movement between the first target surface and the first engagement surface to be achieved when the joint is flexed or articulated, ensuring the target and engagement surfaces remain engaged in the joint and are not displaced, while achieving low friction in the joint to provide good joint function.

[0014] Optionally, the first device body comprises an inflatable portion. The inclusion of an inflatable portion in the device provides cushioning when the device is implanted in a weight bearing joint or a joint that may be otherwise be subject to significant load in the body, e.g. the ankle, knee or hip.

[0015] This may improve comfort for the patient.

[0016] According to an aspect of the disclosure, there is provided a method of manufacturing an orthopaedic device, comprising forming the closed loop of flexible material by bending a flat sheet of the flexible material and joining ends of the flexible material to form the closed loop of flexible material.

[0017] According to an aspect of the disclosure, there is provided a method of implanting a device into a joint of a patient, such that the first engagement surface engages against the first target surface of the joint..

[0018] Embodiments of the disclosure will be further described by way of example only, with reference to the accompanying drawings.

[0019] Figure l is a schematic plan view of an example of an orthopaedic device with a microtextured surface.

[0020] Figures 2 and 3 schematically depict example patterns of the microtextured surface in the region A’ of Figure 1.

[0021] Figure 4 schematically depicts an example of an orthopaedic device with closed loop geometry.

[0022] Figure 5 is a schematic frontal view of an orthopaedic device in place in a knee joint.

[0023] Figure 6 is a sectional view in the sagittal plane (Y-Z plane as illustrated) illustrating the orthopaedic device of Figure 5 in place in the knee joint.

[0024] Figure 7 is a schematic perspective view of the orthopaedic device of Figure 5.

[0025] Figure 8 is a sectional view in the coronal plane (X-Z plane as illustrated) illustrating the orthopaedic device of Figure 5 in place in the knee joint.

[0026] Figure 9 is a perspective view of an orthopaedic device in place in the patello- fem oral joint.

[0027] Figure 10 is a perspective view of an orthopaedic device in place over the head of a femur.

[0028] Figure 11 is a sectional view of the device of Figure 10 in place in a hip joint.

[0029] Embodiments of the present disclosure relate to an orthopaedic device. Figure 1 illustrates an example of the orthopaedic device 1. The device 1 comprises a first device body 10. The first device body 10 comprises a first engagement surface 20 that is configured to engage against a first target surface of a joint of a patient. The first device body 10 comprises a flexible material configured to allow the first engagement surface 20 to deform and thereby conform with the first target surface. For example, the device body 10 may be made of polycarbonate urethane or bio silicone elastomers. These materials are only examples, and the device may be made of any suitably flexible material appropriate for implantation into a patient.

[0030] Figures 2 and 3 illustrate a portion A’ of the first engagement surface 20. The first engagement surface 20 comprises a microtexture. The microtexture is configured to allow movement of cells across the engagement surface 20. For example, stem cells and / or cartilage cells may move between protruding portions 201 of the microtexture (e.g., through regions such as grooves defined by gaps between the protruding portions 201) when the first engagement surface 20 is engaged against the first target surface in the joint of the patient. Stem cells and / or cartilage cells may, for example, move through the microtexture when the device is in place in a joint. The movement may be facilitated by the presence of synovial fluid from the joint between the protruding portions of the microtexture. One application for an orthopaedic device according to the present disclosure is for the treatment of arthritic joints where the cartilage of the joint is damaged. This movement of the stem cells and / or cartilage cells across an area of cartilaginous engagement surface allows for cells from undamaged areas of cartilage to reach the damaged areas of cartilage, which may promote healing of the damaged areas. The microtexture further provides friction between the device and the engagement surface, which may allow an device with the microtexture to remain in place in the joint with minimal other fixtures. This may facilitate installation of the device with minimally invasive surgery, which may be easier to reverse if the joint heals sufficiently for the device to no longer be required.

[0031] The microtexture may comprise a repeating pattern of protruding portions 201 and recessed portions 211 and 212 between the protruding portions. An average separation between the protruding portions 201, in at least a portion of the microtexture, may be in the range of about 50 to 500 pm. In some implementations, the separation is in the range of about 50 to 200 pm, optionally about 75 to 125 pm. An average protruding height of the protruding portions in at least a portion of the microtexture may be in the range of about 50 to 2000 pm. In some implementations, the protruding height is in the range of about 50 to 1000 pm, optionally about 100 to 500 pm, optionally about 150 to 250 pm, optionally about 175 to 225 pm.

[0032] The recessed portions 211 and 212 in the microtexture may define a plurality of grooves. The plurality of grooves may be arranged in a groove pattern. The groove pattern may comprise an interconnected network of grooves 211 and 212. The network of grooves may alternatively or additionally comprise a lattice geometry. In this case, the lattice geometry may be defined as an intersection between a first set of mutually separated grooves 211 and a second set of mutually separated grooves 212.

[0033] The portions of the first engagement surface 20 illustrated in Figures 2 and 3 are examples of lattice geometries. In Figure 2, the grooves in the first set of grooves 211 and the grooves in the second set of grooves 212 are parallel to each other. In Figure 3, although the grooves are not straight, as illustrated the grooves in the first set of grooves 211 and the grooves in the second set of grooves 212 are substantially parallel to each other.

[0034] In Figure 2, the grooves in the first set 211 are angled perpendicularly relative to the grooves in the second set 212. In Figure 3, the grooves in the first set 211 are angled obliquely relative to the grooves in the second set 212.

[0035] The examples of lattice geometries described in Figures 2 and 3 are not exhaustive. Any arrangement or pattern of grooves comprising the lattice geometry is possible, provided that the geometry is suitable to allow stem cells and / or cartilage cells to move across the engagement surface by moving between protruding portions of the microtexture, e.g. through the grooves.

[0036] The lattice geometry may define interstices 201, the interstices being e.g. the shapes defined between the grooves of the lattice (for example when viewed perpendicularly a local plane of the engagement surface). In some implementations, at least a subset of the interstices have substantially the same shape as each other. The interstices may be substantially square, circular, oval, or parallel ogrammical. For example, in Figure 2 the interstices 201 are substantially square. In Figure 3, the interstices 201 are substantially parallelogrammical.

[0037] The first set of grooves 211 and the second set of grooves 212 intersect at multiple points along each groove, such that the first and second set of grooves are interconnected. The interconnections comprise a grid of nodes 202 representing locations of intersections between respective pairs of the grooves. As illustrated in Figures 2 and 3, an average width of the grooves 211 and 212 may be smaller than an average separation between the nodes.

[0038] An average separation between grooves in the first set 211 may be in the range of about 500 to 3000 pm. In some implementations, the average separation between grooves in the first set 211 may be in the range of about 500 to 2000 pm, optionally about 750 to 1500 pm, optionally about 900 to 1100 pm. Alternatively or additionally, an average separation between grooves in the second set 212 may be in the range of about 500 to 3000 pm. In some implementations, the average separation between grooves in the second set 212 may be in the range of about 500 to 2000 pm, optionally about 750 to 1500 pm, optionally about 900 to 1100 pm. The inventors have found that groove patterns having these dimensions provide increased performance in both the movement of cells, including stem cells and / or cartilage cells, across an engagement surface, and providing friction between the device and an engagement surface. An average width of the grooves 211 and 212 in the groove pattern may be in the range of about 50 to 500 pm. In some implementations, the width is in the range of about 50 to 200 pm, optionally about 75 to 125 pm. Alternatively or additionally, an average depth of the grooves of the groove pattern may be in the range of about 50 to 2000 pm. In some implementations, the depth is in the range of about 50 to 1000 pm, optionally about 100 to 500 pm, optionally about 150 to 250 pm, optionally about 175 to 225 pm. The inventors have found that grooves having dimensions in these ranges have good characteristics for the movement of cells in the grooves, so that the cells, including stem cells and / or cartilage cells, can easily move across the engagement surface from undamaged areas to damaged areas of cartilage and promote healing.

[0039] An orthopaedic device according to the present disclosure may be affixed to the joint in which it is implanted. For example, the device 1 illustrated in Figure 1 includes a plurality of fixing extensions 30 that may be used as locations on the device body 10 to fix the device to a joint. The device may be affixed by usual means, such as adhesives, staples, sutures or screws.

[0040] Figure 4 illustrates an implementation in which the first device body 10 comprises a closed loop of flexible material. The closed loop is configured to allow the first engagement surface to deform and thereby conform with the first target surface. As a closed loop, the device body 10 has a continuous inner and outer surface. The closed loop 10 defines an axis B’ passing through the closed loop and two axially opposed openings. In this implementation, the first engagement surface 20 is a radially outward facing portion of the closed loop of flexible material. The first engagement surface 20 may extend over the entirety of the radially outward facing portion of the loop, or may extend only over a portion of the surface, such as only over a portion in the circumferential direction and / or only a portion in the axial direction. The first engagement surface 20 may comprise the microtexture, as illustrated in Figure 4.

[0041] In this implementation, opposite radially inward facing portions 80 of the closed loop of flexible material are configured to be slidably engaged with each other when the first device body 10 is implanted in the joint of the patient. The slidable engagement is such that, during flexing of the joint, relative movement between the first engagement surface 20 and the first target surface is less than relative movement between the slidably engaged inward facing portions 80, and may be substantially zero. In implementations of a device comprising a closed loop with further engagement and target surfaces, the same may apply with respect to these surfaces. The axial openings of the closed loop 10 allow for the synovial fluid naturally present in the joint space to enter the closed loop 10 and flow between the slidably engaged inner surfaces 80. This facilitates low friction between the inner surfaces of the closed loop 10 and hence low friction in the joint in which the device is implanted.

[0042] The closed loop may be configured such that an axis of rotation corresponding to the flexing of the target joint for implantation is substantially parallel to the axis of the closed loop B’, when the device is in place in the joint. This ensures that the direction of sliding between the inner surfaces of the closed loop 10 when the target joint is flexed is in a direction perpendicular to the axis of the closed loop. This provides the largest allowed amplitude of sliding in the device, and avoids twisting or instability in the device during flexure.

[0043] The device body 10 may include one or more further device body portions in addition to the first device body portion 101, each comprising a respective further engagement surface configured to engage against a respective further target surface of the joint of the patient.

[0044] In the example shown in Figure 4, the first device body comprises a first device body portion 101 and a second device body portion 102. Here, the first device body portion 101 comprises the first engagement surface 20, and the second device body portion 102 comprises a second engagement surface (not illustrated). The second engagement surface is configured to engage against a second target surface of the joint of the patient. The second target surface interfaces with the first target surface in the joint of the patient prior to implantation of the device in the joint. The second engagement surface may comprise a microtexture as previously described. The microtexture may be the same as or different from the microtexture of the first engagement surface 20.

[0045] In some implementations, the microtexture on the first and second engagement surfaces is identical, but this is not necessary. Different configurations of the microtexture may be used on the first and second engagement surfaces to account for different physical requirements, such as different loading or frictional conditions, or to account for the need to allow movement of the cells, including stem cells and / or cartilage cells, across surfaces of different sizes.

[0046] In the example shown, the second device body portion 102 also comprises an inflatable portion 1021. The inflatable portion 1021 provides cushioning when the device 1 is implanted in a weight bearing joint or a joint that may be under a load in the body, e.g. the ankle, knee or hip.

[0047] The orthopaedic device of the present disclosure may be adapted for use in the knee. In such a device, the first target surface may comprise one or both of the medial and lateral condyles of a femur. The first device body 10 of the device 1 may be configured such that the first engagement surface conforms with part or all of the articular cartilage surface or surfaces of the respective condyle or condyles. Alternatively or additionally, the first target surface may comprise one or both of the medial or lateral tibial plateaus.

[0048] Figure 5 illustrates an example of an orthopaedic device 1 in place in a knee joint. The orthopaedic device comprises a first device body 10. The implant body 10 has a closed loop geometry, similar to that of the example illustrated in Figure 4. In the example of Figure 5, the closed loop is deformed to the surface of the knee joint, as described later. However, it is possible to construct a device adapted for use in the knee without the closed loop geometry. The device body 10 has a first device body portion 101 and a second device body portion 102. The second device body portion 102 comprises an inflatable portion 1021. The inflatable portion 1021 may provide a high level of cushioning, which may be desirable in joints where high loading is expected, such as in the knee joint. The first device body portion 101 comprises the first engagement surface. In this example, the first target surface comprises the medial condyle 50 of the femur 5 of the knee joint (e.g. the inner or cruciate- adjacent surface of the condyle). The first device body portion 101 is configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the medial condyle 50.

[0049] Figure 6 is a sectional view in the sagittal plane (Y-Z plane as illustrated) through the first device body 10 of Figure 5. Figure 6 shows the first device body 10 of Figure 5 having a closed loop geometry similar to the device body 10 of Figure 4. The closed loop of the device body 10 conforms to the medial condyle 50. The closed loop 10 is formed by the first device body portion 101 and the second device body portion 102. To conform to the surface of the medial condyle 50, the closed loop 10 of Figure 4 is flattened, such that the inner surfaces 80 are slidably engaged, and part of the radially outward facing portion of the flattened closed loop 10 corresponding to the first engagement surface 20 is placed upon and conforms to the rounded surface of the medial condyle 50.

[0050] The second device body portion 102 comprises a second engagement surface 20 configured to engage against a second target surface of the joint of the patient. The second engagement surface also comprises a microtexture configured to allow movement of cells, including stem cells and / or cartilage cells, across the engagement surface 20 by movement of the cells between protruding portions of the microtexture when the second engagement surface is engaged against the second target surface. The microtexture may take any of the forms described herein. In the example of the device 10 of Figure 5, the second target surface comprises the medial tibial plateau 70 of the knee joint. The medial condyle 50 interfaces with the medial tibial plateau 70 and the medial meniscus (which circumscribes part of the medial tibial plateau) in the knee joint prior to implantation. The second device body portion 102 is configured such that the second engagement surface conforms with part or all of the medial tibial plateau 70. The conforming of the second engagement surface 20 to the medial tibial plateau 70 may involve deformation of the inflatable portion 1021. The inflatable portion 1021 may be configured to interface with the concave region formed by the meniscus on the tibial plateau 70, where it can provide cushioning to improve comfort when weight is placed through the joint. In this case, the inflatable portion 1021 may interface with part or all of the articular surface of the tibial plateau 70 not covered by the meniscus. The device 10 further includes an inflation channel 60 fluidically coupled to the inflatable portion. The inflation channel 60 can be configured to allow the inflatable portion 1021 to be inflated by pumping fluid through the inflation channel to the inflatable portion. The inflation may take place after the device is in place in the joint. In some implementations, the inflation channel 60, a surrounding tab or other mechanical feature associated with the inflation channel 60 may be used as a fixation point to fix the device in place in the joint, in place of additional fixing extensions. In some implementations, at least a part of the surrounding tab may be configured to fit under the medial or lateral meniscus to help hold the inflatable portion 1021 in place.

[0051] As previously described, the opposite radially inward facing portions 80 of the closed loop are slidably engaged as the closed loop conforms to the target surfaces in the knee joint. The relative movement between the first and second engagement surfaces and first and second target surfaces is less than the relative movement between the opposite radially inward facing portions 80, and may be substantially zero. This allows for the first engagement surface 20 to remain in contact with the cartilage surface of the medial condyle 50 and the second the second engagement surface 20 to remain in contact with part or all of the medial tibial plateau 70. This ensures that the first and second engagement surfaces 20 are not displaced from their respective target surfaces, and that the inflatable portion 1021 stays in place to provide cushioning across a large range of motion of the knee joint when weight is placed through the joint.

[0052] An orthopaedic device according to the present disclosure may further comprise one or more further device bodies. Each further device body may comprise one or more respective further engagement surfaces configured to engage against one or more respective further target surfaces of the joint of the patient. The one or more respective further engagement surfaces of the further device bodies may each comprise a microtexture. The microtexture may take any of the forms described herein.

[0053] Such an device may comprise a second device body comprising a third device body portion and a fourth device body portion. In such an device, the third device body portion may comprise a third engagement surface configured to engage against a third target surface of the joint of the patient. The fourth device body portion may comprise a fourth engagement surface configured to engage against a fourth target surface of the joint of the patient. The third target surface may interface with the fourth target surface in the joint prior to implantation of the device in the joint. For example, the orthopaedic device 1 illustrated in Figure 5 also comprises a second device body 11. The second device body 11 comprises a third device body portion 111 and a fourth device body portion 112. The third device body portion I l l is configured similarly to the first device body portion 101 of the first device body as described above. However, the third target surface comprises the lateral condyle 51 (e.g. the inner or cruciate-adjacent surface of the condyle) of the knee joint, the second device body 11 being configured such that the third engagement surface conforms with part or all of the articular cartilage surface of the lateral condyle 51. The fourth device body portion 112 is configured similarly to the second device body portion 102, except that the fourth target surface comprises the lateral tibial plateau 71, the fourth engagement surface being configured to conform with part or all of the lateral tibial plateau 71. The fourth device body portion also comprises an inflatable portion 1121.

[0054] The use of two device bodies when providing an device for a knee joint according to the present disclosure is not necessary. In some implementations, only one of the device bodies 10 or 11 may be in place in the knee joint e.g., if only half of the knee requires treatment. Alternatively, the four device body portions described above may be provided in a single device body. For example, the first device body 10 and second device body 11 may be joined to form a single device body.

[0055] In the above example, the first device body 10 and second device body 11 are configured to engage with different target surfaces in the lateral and medial sides of the knee joint. Accordingly, the first device body 10 and second device body 11 may be adapted to better interface with these surfaces. For example, the shapes of the first and second device bodies may be mirrored relative to one another, or they may be dimensionally adapted for placement in the target side of the knee.

[0056] Figure 8 illustrates a sectional view in the coronal plane (X-Z plane as illustrated) of the first and second device bodies 10 and 11 of Figures 5 and 7. As shown in Figure 8, the device bodies may further comprise a plurality of fixing extensions 30. In Figure 8, the fixing extensions 30 are fixed to the inner side of the femoral condyles. Only one, or more than one fixing extension per device body may be used to fix the device to the joint. In the case where more than one device body is provided, the device bodies are not required to have the same number of affixation points. The device bodies 10 and 11 may be configured to be affixed to the joint only by the fixing of one or more of the fixing extensions to the tibia 7 and the fixing of one or more of the fixing extensions to the inner side of the femoral condyles 50 and 51. In some implementations, no further affixation points are necessary.

[0057] In Figure 5, one or more of the fixing extensions fixed to the tibia comprise the inflation channels 60 of the device bodies. However, the fixing extensions fixed to the tibia may be provided separately to the inflation tubes in some implementations.

[0058] In an implementation illustrated in Figure 9, the device is configured for use in the patella-femoral joint, between the patella and femur. In this implementation, the device body 10 has a closed loop geometry similar to the device body of Figure 4. The first engagement surface 20 may comprise a microtexture. Here, the first target surface is the posterior surface of the patella 60, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the patella. In this implementation, the second target surface may be the anterior surface 52 of the femur. The device body 105 may be affixed to the tibia 7 by means of a fixing extension 30.

[0059] In another implementation illustrated in Figures 10 and 11, an device according to this disclosure is adapted for use in the hip joint. As the hip joint is a ball and socket type joint, movement is required in substantially all directions, and as such the closed loop geometry for the device body is not used. In this implementation, a double bubble (or invaginated partially inflated balloon) structure may be used instead of the closed loop. In this implementation, the first device body portion 106 comprises a first engagement surface (not illustrated) and is configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the femoral head 54, the femoral head 54 being the first target surface. The second device body portion 107 comprises a second engagement surface 20 configured such that the engagement surface conforms with part or all of the articular cartilage surface of the acetabulum 90, the acetabulum 90 being the second target surface. One or both of the first engagement surface and second engagement surface 20 may comprise the microtexture. In this implementation, the second device body portion 107 may comprise an inflatable portion 1071. The edges of the portion 107 may comprise fixing extensions to allow fixation to the edge of the acetabulum. The first device portion 106 may comprise fixing extensions 30 configured to be fixed to the femoral neck 55. The fixing to the femoral neck 55 may be at the point of invagination of the balloon. The fixing extensions 30 may be equally spaced around the circumference of the device, e.g. 3 fixing extensions 30 arranged at 120 degree intervals.

[0060] An orthopaedic device according to the present disclosure may be adapted to further target joints other than those already described. A device having a microtextured engagement surface may be used in any joint of a patient to enable the movement of cells, including stem cells and / or cartilage cells, across the engagement surface and corresponding target surface. Examples of further joints the device may be suitable for use in include the shoulder or the intervertebral joints. Alternatively or additionally, a device having closed loop geometry as illustrated in Figure 4 may be used in any joint with substantially one axis of rotation, such as the finger or ankle.

[0061] Any example of an orthopaedic device described herein may be may be suitable for implantation via arthroscopic surgery. Configuring the device to be suitable to be implanted in this way allows for the implantation to take place with minimally invasive surgery, reducing patient recovery time and enabling joint treatment to be offered to a wider group of patients. For example, it may enable older patients who cannot undergo a traditional full joint replacement to be treated.

[0062] A method for manufacturing an orthopaedic device having the closed loop geometry of Figure 4 comprises forming the closed loop of flexible material by bending a flat sheet of the flexible material and joining the ends of the flexible material to form the closed loop of flexible material. Where the device contains an inflatable portion, the method may further include forming the inflatable portion in a separate inflatable body, and joining the separate inflatable body to the flexible material, before or after it has been formed into the closed loop. In this way, a single device body having a closed loop geometry and an inflatable portion can be formed.

[0063] Additionally, the method may further include forming a receiving portion in the flexible material shaped to receive and conform in shape with at least a portion of the separate inflatable body. Manufacturing the device body in this way may provide improved performance of the device whilst remaining simple and cost-effective to manufacture.

[0064] A method of implanting an device according to the present disclosure into a joint of a patient is now described. The method includes implanting the device such that the first engagement surface engages against the first target surface of the joint. If the first device body comprises a closed loop of flexible material configured to conform with the first target surface, the method may include implanting the first device body such that an axis of rotation corresponding to the flexing of the joint is substantially parallel to the axis of the closed loop. This ensures that the device will provide reduced friction in the direction of significant flexure and hence increased performance once implanted into the joint.

[0065] If the first device body comprises an inflatable portion and an inflation channel fluidically coupled to the inflatable portion as previously described, the method of implantation may further include fixedly connecting the inflation channel to a bone structure of the joint of the patient to fix the device in the joint of the patient. This will involve the device being introduced by a small incision during arthroscopy and inflated inside the joint by structures as highlighted in inflation tubes 60.

[0066] The following numbered clauses define aspects of the invention:

[0067] 1. An orthopaedic device, comprising: a first device body comprising a first engagement surface configured to engage against a first target surface of a joint of a patient, wherein: the first device body comprises a flexible material configured to allow the first engagement surface to deform and thereby conform with the first target surface; and the first engagement surface comprises a microtexture configured to allow movement of cells across the engagement surface by movement of the cells between protruding portions of the microtexture when the first engagement surface is engaged against the first target surface.

[0068] 2. The device of aspect 1, wherein the microtexture comprises a repeating pattern of the protruding portions and recessed portions between the protruding portions, wherein an average separation between the protruding portions in at least a portion of the microtexture is in the range of about 50 to 500 pm and / or an average protruding height in at least a portion of the microtexture is in the range of about 50 to 2000 pm.

[0069] 3. The device of aspect 1 or 2, wherein the recessed portions define a plurality of grooves.

[0070] 4. The device of aspect 3, wherein the plurality of grooves is arranged in a groove pattern, the groove pattern comprising an interconnected network of grooves.

[0071] 5. The device of aspect 4, wherein the network comprises a lattice geometry defined as an intersection between a first set of mutually separated grooves and a second set of mutually separated grooves. 6. The device of aspect 5, wherein: the grooves in the first set are substantially parallel to each other; and / or the grooves in the second set are substantially parallel to each other.

[0072] 7. The device of aspect 6, wherein the grooves in the first set are angled obliquely or perpendicularly relative to the grooves in the second set.

[0073] 8. The device of any of aspects 5 to 7, wherein the lattice geometry defines interstices, at least a subset of the interstices having substantially the same shape as each other.

[0074] 9. The device of any of aspects 5 to 8, wherein lattice geometry defines interstices that are substantially square, rhombic, circular, oval or parallel ogrammical.

[0075] 10. The device of any of aspects 5 to 9, wherein: the lattice geometry comprises a grid of nodes representing locations of intersections between respective pairs of the grooves; and an average width of the grooves is smaller than an average separation between the nodes.

[0076] 11. The device of any of aspects 5 to 10, wherein: an average separation between grooves in the first set is in the range of about 500 to 3000 pm; and / or an average separation between grooves in the second set is in the range of about 500 to 3000 pm.

[0077] 12. The device of any of aspects 4 to 11, wherein an average width of the grooves in the groove pattern is in the range of about 50 to 500 and / or an average depth of the grooves of the groove pattern is in the range of about 50 to 2000 pm.

[0078] 13. The device of any preceding aspect, wherein: the first device body comprises a closed loop of the flexible material configured to conform with the first target surface; the closed loop defines an axis passing through the closed loop and two axially opposed openings; and the first engagement surface is a radially outward facing portion of the closed loop of the flexible material.

[0079] 14. An orthopaedic device, comprising: a first device body comprising a first engagement surface configured to engage against a first target surface of a joint of a patient, wherein: the first device body comprises a closed loop of flexible material configured to allow the first engagement surface to deform and thereby conform with the first target surface; the closed loop defines an axis passing through the closed loop and two axially opposed openings; and the first engagement surface is a radially outward facing portion of the closed loop of flexible material.

[0080] 15. The device of aspect 13 or 14, wherein opposite radially inward facing portions of the closed loop of flexible material are configured to be slidably engaged with each other when the first device body is implanted in the joint of the patient, the slidable engagement being such that, during flexing of the joint, relative movement between the first engagement surface and the first target surface is substantially zero or at least less than relative movement between the slidably engaged inward facing portions.

[0081] 16. The device of aspect 15, configured such that an axis of rotation corresponding to the flexing of the joint is substantially parallel to the axis of the closed loop.

[0082] 17. The device of any preceding aspect, wherein the first target surface comprises: one or both of the medial and lateral condyles of a femur, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface or surfaces of the respective condyle or condyles; and / or the posterior surface of the patella, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the patella; and / or the head of a femur, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the femoral head; and / or acetabulum of the hip joint, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the acetabulum; and / or one or both of the medial or lateral tibial plateaus.

[0083] 18. The device of any preceding aspect, wherein the first device body comprises an inflatable portion.

[0084] 19. The device of any of aspects 1-18, further comprising: one or more further device body portions, each further device body portion comprising a respective further engagement surface configured to engage against a respective further target surface of the joint of the patient; and one or more of the further device body portions comprises an inflatable portion.

[0085] 20. The device of aspect 18 or 19, further comprising an inflation channel fluidically coupled to the inflatable portion and configured to allow the inflatable portion to be inflated by pumping fluid through the inflation channel to the inflatable portion.

[0086] 21. The device of any of aspects 1-20, wherein: the first device body comprises a first device body portion and a second device body portion, wherein: the first device body portion comprises the first engagement surface; the second device body portion comprises a second engagement surface configured to engage against a second target surface of the joint of the patient; the second engagement surface comprises a microtexture configured to allow movement of cells across the engagement surface by movement of the cells between protruding portions of the microtexture when the second engagement surface is engaged against the second target surface; and the second target surface interfaces with the first target surface in the joint of the patient prior to implantation of the device in the joint.

[0087] 22. The device of aspect 21, wherein the first target surface comprises one of the medial or lateral condyles of a femur of a knee joint, the first device body portion being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the respective condyle; and the second target surface comprises the respective medial or lateral tibial plateau of the knee joint, the second device body portion being configured such that the second engagement surface conforms with part or all of the tibial plateau.

[0088] 23. The device of aspect 22, wherein the second device body portion comprises the inflatable portion.

[0089] 24. The device of any preceding aspect, wherein: the device comprises one or more further device bodies, each further device body comprising one or more respective further engagement surfaces configured to engage against one or more respective further target surfaces of the joint of the patient; and the one or more respective further engagement surfaces comprise a microtexture configured to allow movement of cells across the engagement surface by movement of the cells between protruding portions of the microtexture when each further engagement surface is engaged against the each further target surface.

[0090] 25. The device of aspect 24, further comprising: a second device body comprising a third device body portion and a fourth device body portion, wherein: the third device body portion comprises a third engagement surface configured to engage against a third target surface of the joint of the patient; the fourth device body portion comprises a fourth engagement surface configured to engage against a fourth target surface of the joint of the patient; and the third target surface interfaces with the fourth target surface in the joint prior to implantation of the device in the joint.

[0091] 26. The device of aspect 25, wherein: the first target surface comprises the medial condyle of the knee joint, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the medial condyle; the second target surface comprises the medial tibial plateau; the third target surface comprises the lateral condyle of the knee joint, the second device body being configured such that the third engagement surface conforms with part or all of the articular cartilage surface of the lateral condyle; and the fourth target surface comprises the lateral tibial plateau.

[0092] 27. The device of aspect 26, wherein the second and fourth device body portions comprise inflatable portions.

[0093] 28. The device of aspects 21 or 26, wherein the device bodies further comprise a plurality of fixing extensions, and the device is configured to be affixed to the joint only by the fixing of one or more of the fixing extensions to the tibia and the fixing of one or more of the fixing extensions to the inner side of the femoral condyles. 29. The device of aspect 28, wherein one or more of the fixing extensions fixed to the tibia comprise inflation channels of the device bodies.

[0094] 30. The device of aspect 21, wherein: the first target surface comprises posterior surface of a patella, the first device body portion being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the patella; and the second target surface comprises the respective anterior surface of a femur, the second device body portion being configured such that the second engagement surface conforms with part or all of the articular cartilage surface on the anterior surface of the femur.

[0095] 31. The device of aspect 21, wherein: the first target surface comprises the head of a femur in a hip joint, the first device body portion being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the femoral head; and the second target surface comprises the respective acetabulum of the hip joint, the second device body portion being configured such that the second engagement surface conforms with part or all of the articular cartilage surface of the acetabulum.

[0096] 32. The orthopaedic device according to any preceding aspect, wherein the device is suitable for implantation via arthroscopic surgery.

[0097] 33. A method of manufacturing an orthopaedic device, wherein: the device is according to any one of aspects 13-15; and the method comprises forming the closed loop of flexible material by bending a flat sheet of the flexible material and joining ends of the flexible material to form the closed loop of flexible material.

[0098] 34. The method of aspect 33, wherein: the device further comprises an inflatable portion; the method further comprises forming the inflatable portion in a separate inflatable body and joining the separate inflatable body to the flexible material.

[0099] 35. The method of aspect 34, wherein the method further comprises forming a receiving portion in the flexible material shaped to receive and conform in shape with at least a portion of the separate inflatable body.

[0100] 36. A method of implanting an device into a joint of a patient, comprising: implanting the device of any of aspects 1-32 such that the first engagement surface engages against the first target surface of the joint.

[0101] 37. The method of aspect 36, wherein: the device comprises an inflatable portion; and the method further comprises implanting the device with the inflatable portion deflated, and inflating the device once the device is implanted into the joint.

[0102] 38. The method of aspect 36 or 37, wherein: the first device body comprises a closed loop of flexible material configured to conform with the first target surface; the closed loop defines an axis passing through the closed loop and two axially opposed openings; the first engagement surface is a radially outward facing portion of the closed loop of flexible material; and the method comprises implanting the first device body such that an axis of rotation corresponding to the flexing of the joint is substantially parallel to the axis of the closed loop.

[0103] 39. The method of aspect 34 or 35, wherein: the first device body comprises an inflatable portion; the device comprises an inflation channel fluidically coupled to the inflatable portion and configured to allow the inflatable portion to be inflated by pumping fluid through the inflation channel to the inflatable portion; and the method comprises fixedly connecting the inflation channel to a bone structure of the joint of the patient to fix the device in the joint of the patient.

[0104] Cross reference to related applications

[0105] This application claims priority from GB 2411165.0 filed on 30 July 2024, the contents of which are hereby incorporated by reference.

Claims

CLAIMS1. An orthopaedic device, comprising: a first device body comprising a first engagement surface configured to engage against a first target surface of a joint of a patient, wherein: the first device body comprises a flexible material configured to allow the first engagement surface to deform and thereby conform with the first target surface; and the first engagement surface comprises a microtexture configured to allow movement of cells across the engagement surface by movement of the cells between protruding portions of the microtexture when the first engagement surface is engaged against the first target surface.

2. The device of claim 1, wherein the microtexture comprises a repeating pattern of the protruding portions and recessed portions between the protruding portions, wherein an average separation between the protruding portions in at least a portion of the microtexture is in the range of about 50 to 500 pm and / or an average protruding height in at least a portion of the microtexture is in the range of about 50 to 2000 pm.

3. The device of claim 1 or 2, wherein the recessed portions define a plurality of grooves.

4. The device of claim 3, wherein the plurality of grooves is arranged in a groove pattern, the groove pattern comprising an interconnected network of grooves.

5. The device of claim 4, wherein the network comprises a lattice geometry defined as an intersection between a first set of mutually separated grooves and a second set of mutually separated grooves.

6. The device of claim 5, wherein: the grooves in the first set are substantially parallel to each other; and / or the grooves in the second set are substantially parallel to each other.

7. The device of claim 6, wherein the grooves in the first set are angled obliquely or perpendicularly relative to the grooves in the second set.

8. The device of any of claims 5 to 7, wherein the lattice geometry defines interstices, at least a subset of the interstices having substantially the same shape as each other.

9. The device of any of claims 5 to 8, wherein: an average separation between grooves in the first set is in the range of about 500 to 3000 pm; and / or an average separation between grooves in the second set is in the range of about 500 to 3000 pm.

10. The device of any of claims 4 to 9, wherein an average width of the grooves in the groove pattern is in the range of about 50 to 500 and / or an average depth of the grooves of the groove pattern is in the range of about 50 to 2000 pm.

11. The device of any preceding claim, wherein: the first device body comprises a closed loop of the flexible material configured to conform with the first target surface; the closed loop defines an axis passing through the closed loop and two axially opposed openings; and the first engagement surface is a radially outward facing portion of the closed loop of the flexible material.

12. An orthopaedic device, comprising: a first device body comprising a first engagement surface configured to engage against a first target surface of a joint of a patient, wherein: the first device body comprises a closed loop of flexible material configured to allow the first engagement surface to deform and thereby conform with the first target surface; the closed loop defines an axis passing through the closed loop and two axially opposed openings; andthe first engagement surface is a radially outward facing portion of the closed loop of flexible material.

13. The device of claim 11 or 12, wherein opposite radially inward facing portions of the closed loop of flexible material are configured to be slidably engaged with each other when the first device body is implanted in the joint of the patient, the slidable engagement being such that, during flexing of the joint, relative movement between the first engagement surface and the first target surface is substantially zero or at least less than relative movement between the slidably engaged inward facing portions.

14. The device of claim 13, configured such that an axis of rotation corresponding to the flexing of the joint is substantially parallel to the axis of the closed loop.

15. The device of any preceding claim, wherein the first target surface comprises: one or both of the medial and lateral condyles of a femur, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface or surfaces of the respective condyle or condyles; and / or the posterior surface of the patella, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the patella; and / or the head of a femur, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the femoral head; and / or acetabulum of the hip joint, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the acetabulum; and / or one or both of the medial or lateral tibial plateaus.

16. The device of any preceding claim, wherein the first device body comprises an inflatable portion.

17. The device of any of claims 1 tol6, further comprising:one or more further device body portions, each further device body portion comprising a respective further engagement surface configured to engage against a respective further target surface of the joint of the patient; and one or more of the further device body portions comprises an inflatable portion.

18. The device of any of claims 1 to 17, wherein: the first device body comprises a first device body portion and a second device body portion, wherein: the first device body portion comprises the first engagement surface; the second device body portion comprises a second engagement surface configured to engage against a second target surface of the joint of the patient; the second engagement surface comprises a microtexture configured to allow movement of cells across the engagement surface by movement of the cells between protruding portions of the microtexture when the second engagement surface is engaged against the second target surface; and the second target surface interfaces with the first target surface in the joint of the patient prior to implantation of the device in the joint.

19. The device of claim 18, wherein the first target surface comprises one of the medial or lateral condyles of a femur of a knee joint, the first device body portion being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the respective condyle; and the second target surface comprises the respective medial or lateral tibial plateau of the knee joint, the second device body portion being configured such that the second engagement surface conforms with part or all of the tibial plateau.

20. The device of claim 19, wherein the second device body portion comprises the inflatable portion.

21. The device of any preceding claim, wherein:the device comprises one or more further device bodies, each further device body comprising one or more respective further engagement surfaces configured to engage against one or more respective further target surfaces of the joint of the patient; and the one or more respective further engagement surfaces comprise a microtexture configured to allow movement of cells across the engagement surface by movement of the cells between protruding portions of the microtexture when each further engagement surface is engaged against the each further target surface.

22. The device of claim 21, further comprising: a second device body comprising a third device body portion and a fourth device body portion, wherein: the third device body portion comprises a third engagement surface configured to engage against a third target surface of the joint of the patient; the fourth device body portion comprises a fourth engagement surface configured to engage against a fourth target surface of the joint of the patient; and the third target surface interfaces with the fourth target surface in the joint prior to implantation of the device in the joint.

23. The device of claim 22, wherein: the first target surface comprises the medial condyle of the knee joint, the first device body being configured such that the first engagement surface conforms with part or all of the articular cartilage surface of the medial condyle; the second target surface comprises the medial tibial plateau; the third target surface comprises the lateral condyle of the knee joint, the second device body being configured such that the third engagement surface conforms with part or all of the articular cartilage surface of the lateral condyle; and the fourth target surface comprises the lateral tibial plateau.

24. The device of claim 23, wherein the second and fourth device body portions comprise inflatable portions.

25. The device of claims 18 or 23, wherein the device bodies further comprise a plurality of fixing extensions, and the device is configured to be affixed to the joint only by the fixing of one or more of the fixing extensions to the tibia and the fixing of one or more of the fixing extensions to the inner side of the femoral condyles.

Images