Support and holder for navigation systems

Abstract

A holder (1) for at least one marker of a navigation system is disclosed. The holder (1) comprises a body (2) having at least one area for the at least one marker and a hub (4) for attaching the holder (1) to a retainer. The hub (4) comprises at least one reference surface (6) at a first end of the hub (4), at least one deflectable element (7) at a second end of the hub (4), at least one support guide surface (8) extending at least partially between the reference surface (6) and the deflectable element (7), and a snap-fit feature (9) at the deflectable element (7). A retainer (20) for the holder (1) is also disclosed.

Description

[0001] Embodiments of this application generally relate to the field of navigation systems, such as optical surgical navigation systems. More particularly, the present invention relates to a support for at least one mark in a navigation system. The support includes: a body having at least one region for the at least one mark; and a hub for attaching the support to a retainer. The hub includes at least one reference surface, at least one deflectable element, at least one guide surface, and a snap-fit ​​feature. The hub may include a central longitudinal axis defining an axial direction of the hub. The at least one reference surface may be located at a first end of the hub and / or may be radially positioned at a first distance from the central longitudinal axis. The at least one deflectable element may be located at a second end of the hub and / or may be radially positioned at a second distance from the central longitudinal axis. The at least one guide surface may extend at least partially between the reference surface and the deflectable element. The snap-fit ​​feature may be located at the deflectable element.

[0002] Embodiments of this application also relate to a retainer (e.g., for a bracket). The retainer includes: a protrusion extending in a radial or lateral direction of the retainer; at least one arm extending in a radial or lateral direction of the retainer; and a guide surface extending at least partially between the protrusion and the arm. The arm may include a sliding surface that is inclined in a non-perpendicular direction relative to the axial direction of the retainer. The arm may be spaced apart from the protrusion. Background Technology

[0003] Navigation systems (such as optical navigation systems) can be used to indicate location in space or track objects in space. For example, an optical navigation system may include a camera system that projects infrared (IR) light onto a reflective marker. The reflective marker may include a retroreflective material to reflect the projected light. The camera system can capture the reflected light and determine the marker's location. A single marker can be used to indicate location in space. Multiple markers with fixed and predetermined patterns can be used to track various objects in space in six degrees of freedom. Active optical navigation systems use active markers, where the marker projects light (e.g., via LEDs), which the camera system can detect.

[0004] Optical navigation systems can be used in a variety of applications, such as for assembling parts with high precision, for example in automotive, aerospace, and medical applications. In medical applications, for instance, optical navigation systems can be used to track instruments and / or locate medical devices during surgery.

[0005] Passive retroreflective markers are known to be used in a variety of applications. In some applications, the sphere is detachably mounted to a support, which can then be attached to or integrated with an instrument or tool. Detachable supports typically have multiple struts in a predetermined pattern, to which the sphere is attached using threaded or ring-locking connectors. Other systems use disc-shaped markers. A common feature of these systems is that multiple markers (often at least four) must be mounted to the support to track objects with six degrees of freedom. This can be time-consuming. Particularly in medical applications, if used during surgery, the markers need to be sterile. For such applications, the markers are either single-use and disposable or sterilizable. If sterilizable, the markers need to be removed from the support after use to allow for thorough cleaning and sterilization before the next procedure. The markers must be attached to the support before each procedure.

[0006] The accuracy of navigation systems is typically in the sub-millimeter range. Therefore, markers (such as reflective spheres or disks) must be attached to the support very precisely, and the support needs to be attached to another device in a stable manner so as not to degrade the accuracy during use.

[0007] Assembling the markers onto the support adds time to the preparation for using the navigation system, which should be minimized in most applications. In medical applications, time is of the essence, and the time available for assembling the components of the optical navigation system is limited. Furthermore, the support needs to be attached to other devices in a stable manner. Summary of the Invention

[0008] It is desirable to reduce the time required to assemble components of a navigation system. In particular, it is desirable to provide a bracket that can be quickly and stably attached to another component. It is also desirable to provide a retainer to which the bracket can be quickly and stably attached.

[0009] Accordingly, embodiments of the present invention preferably aim to mitigate, alleviate, or eliminate one or more deficiencies, disadvantages, or problems in the art (such as those described above) by providing supports and retainers according to the appended patent claims, either alone or in any combination.

[0010] According to an embodiment, a bracket for at least one mark in a navigation system includes: a body having at least one region for the at least one mark; and a hub for attaching the bracket to a retainer. The hub includes: a central longitudinal axis defining an axial direction of the hub; at least one reference surface located at a first end of the hub and radially positioned at a first distance from the central longitudinal axis; at least one deflectable element located at a second end of the hub and radially positioned at a second distance from the central longitudinal axis; at least one guide surface extending at least partially between the reference surface and the deflectable element; and a snap-fit ​​feature located at the deflectable element.

[0011] The deflectable element may have a base and a free end. The base may be connected to the body, and the deflectable element may extend in the axial direction of the hub.

[0012] The height of the deflectable element can vary in the tangential direction of the hub, which is measured in the axial direction of the hub from the base to the free end.

[0013] The free end of the deflectable element can be positioned at least partially off-center around the central longitudinal axis.

[0014] The top surface of the free end can be tilted toward the reference surface and toward the central longitudinal axis, for example, inward toward the central longitudinal axis and toward the reference surface.

[0015] Snap-fit ​​features may include recesses, such as V-shaped recesses.

[0016] The first distance can be different from the second distance. The first distance can be less than the second distance.

[0017] The guide surface may include a first portion and a second portion. The first portion may have a cylindrical cross-section in the axial direction of the hub. The second portion may have a tapered cross-section in the axial direction of the hub.

[0018] The hub may include at least one groove having an open end toward a central longitudinal axis and a closed end toward the periphery of the hub. The closed end may be positioned closer to the periphery of the hub than at least a portion of the deflectable element.

[0019] The body may include multiple arms positioned around the hub. Each arm may have an area for marking.

[0020] According to an embodiment, a retainer (e.g., a retainer for a support embodiment) includes: a protrusion extending in a lateral direction of the retainer; at least one arm extending in the lateral direction of the retainer; and a guide surface extending at least partially between the protrusion and the arm. The arm is spaced apart from the protrusion, and the arm includes a sliding surface that is inclined in a non-perpendicular direction relative to the axial direction of the retainer.

[0021] The sliding surface can be circular in the tangential direction of the retainer.

[0022] The arm may have a base and a free end, and a sliding surface may extend at least partially between the base and the free end and may have a first region and a second region. The first region may be positioned closer to the base than the second region. A first axial distance may be shorter than a second axial distance, the first axial distance being measured from the distal portion of the first region to the protrusion, and the second axial distance being measured from the distal portion of the second region to the protrusion.

[0023] The sliding surface may have a peak that forms the distal portion of the first region and the distal portion of the second region. The peak may be substantially straight between the first and second regions and may be inclined relative to the lateral direction of the retainer.

[0024] Further embodiments of the invention are defined in the dependent claims.

[0025] Embodiments of the present invention provide a bracket for markers in a navigation system, which can be stably assembled with another device. The markers for the navigation system can be attached to the bracket, allowing multiple markers to be secured to other instruments using a single component, simplifying and speeding up assembly. For example, the bracket can be assembled with a retainer without altering the hand grip. Thus, a single component can be used to attach multiple markers, yet the connection between components remains stable. Further advantages of the embodiments are described below.

[0026] It should be emphasized that, when used in this specification, the term "comprises / comprising" is used to specify the presence of a stated feature, integral, step, or component, but does not exclude the presence or addition of one or more other features, integrals, steps, components, or groups thereof. Attached Figure Description

[0027] Referring to the accompanying drawings, these and other aspects, features, and advantages of the embodiments of the present invention will become apparent and will be elucidated from the following description of the embodiments of the present invention, in which: Figure 1a This is a top view showing an embodiment of the display stand; Figure 1b yes Figure 1a Top-view 3D view of the support structure; Figure 1c yes Figure 1a A bottom view of the support frame; Figure 1d yes Figure 1c A three-dimensional view of the support structure from below; Figure 1e This is a cross-sectional perspective view showing an embodiment of the hub; Figure 2a This is a top perspective view showing an embodiment of the retainer; Figure 2b It is viewed from the first observation direction. Figure 2a Side view of the retainer; and Figure 2c It is viewed from the second direction of observation. Figure 2a A side view of the retainer, the side view relative to Figure 2b The side view has been rotated 90 degrees. Detailed Implementation

[0028] Specific embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The terminology used in the detailed description of the embodiments shown in the drawings is not intended to limit the invention. In the drawings, similar numerals refer to similar elements.

[0029] The following description focuses on embodiments of the invention applicable to surgical navigation systems, in which not only accuracy is important, but also ease of assembly to accommodate the limited time available for surgical preparation is also crucial. However, it will be understood that the invention is not limited to this application, but can be applied to many other procedures, such as component assembly processes, inspection processes, and measurement processes.

[0030] In various embodiments, the present invention may include one or more components and elements having the same structure. Therefore, in the accompanying drawings, components having the same structure are indicated by the same reference numerals. However, it should be understood that not all components shown are included in all embodiments. In the following description, one of the components of an embodiment will be described, and additional effects of embodiments including more than one structure are described to illustrate the effects achieved through combination.

[0031] Figures 1a to 1e A bracket 1 for at least one marker used in a navigation system is shown, and Figure 2aFigure 2e illustrates retainer 20 (e.g., for support 1). Support 1 and retainer 20 can be manufactured and delivered separately. For example, support 1 can be a pre-sterilized single-use component, while retainer 20 can be a reusable, re-sterilized component. Hereinafter, support 1 will be described first, followed by retainer 20, and finally, various aspects of the components and assembly process including support 1 and retainer 20 will be discussed.

[0032] support The support 1 can be used to attach markers to a navigation system in a fixed position. The support 1 can be manufactured separately from the markers, such as by milling or injection molding. The markers can be optical components, such as passive retroreflective materials or active LEDs. The support 1 can include one or more markers depending on the number of degrees of freedom the support should track. After the markers have been attached to the support 1, the assembly can be packaged, sterilized, and delivered for use in a sterile environment. The markers can be permanently attached to the support 1, such as by gluing. Therefore, the user of the support does not need to handle the markers. This is particularly useful when using multiple markers, where multiple markers can be attached to another device by handling only the support 1. For example, in embodiments of the support 1 with three or more markers (e.g., four to six markers), all markers can be assembled in a stable manner in a single assembly step. This significantly reduces the time required to attach markers to other devices (e.g., instruments) using the support 1 of these embodiments, while still completing the process in a stable manner. In surgical situations, a navigation system (e.g., an optical navigation system) can be used to track instruments. This can be useful when time is limited for surgical preparation. Therefore, in such cases, the ability to attach multiple tags to the instrument using a single bracket 1 is particularly useful. Furthermore, ease of handling is important in surgical situations, as surgical personnel wear protective clothing and gloves. Therefore, it is also advantageous to attach multiple tags using a single bracket 1 for this reason. Further advantages of the bracket 1 and retainer 20 according to the invention will be explained below.

[0033] Figures 1a to 1e The embodiment of the support 1 shown includes a body 2 having at least one region 3 for at least one mark. In the shown embodiment, the support 1 includes four regions 3 for marking, but may include fewer or more than four regions 3 for marking. In the shown embodiment, the region 3 for marking is placed in a single plane and has a predetermined fixed pattern, thereby enabling high-precision tracking of the attached mark support 1 for up to six degrees of freedom.

[0034] Figure 1e This demonstrates the method for attaching the bracket 1 to the retainer 20 ( Figures 2a to 2c Various details of the hub 4. The hub 4 includes a central longitudinal axis 5 that defines the axial direction of the hub 4. Figures 1a to 1dThe horizontal axis (not shown in the figure) is perpendicular to the central longitudinal axis 5.

[0035] As in Figures 1c to 1d As can be seen, the hub 4 includes at least one reference surface 6 located at a first end of the hub 4 and radially positioned at a first distance from the central longitudinal axis 5. The first end of the hub 4 may be the bottom or distal end of the support 1. The reference surface 6 may have an extension or width in the lateral direction of the hub 4 and extends at least partially around the central longitudinal axis 5. The reference surface 6 provides a fixed predetermined position for the support 1, relative to which other elements (e.g., region 3) may be positioned.

[0036] As in Figures 1a to 1b as well as Figure 1e As can be seen, the hub 4 includes at least one deflectable element 7 located at a second end of the hub 4 and radially positioned at a second distance from the central longitudinal axis 5. The second end of the hub 4 may be the top or proximal end of the bracket 1. The second end of the hub 4 may, for example, point towards a camera or other type of measuring device of a navigation system used to determine the position of the bracket 1 and any devices connected to the bracket 1.

[0037] As in Figure 1a , Figure 1d and Figure 1e As can be seen, the hub 4 includes at least one guide surface 8 that extends at least partially between the reference surface 6 and the deflectable element 7. For example, the guide surface 8 can extend from the reference surface 6 toward the deflectable element 7. When the deflectable element 7 is deflected, the guide surface 8 can provide stability of the support 1 in the lateral direction.

[0038] As in Figures 1a to 1e As can be seen, the hub includes a snap-fit ​​feature 9 to lock the bracket to another device (e.g., retainer 20). The snap-fit ​​feature 9 may be located at the deflectable element 7.

[0039] In the illustrated embodiment, the deflectable element 7 has a base and a free end. The free end may have a top surface 10. The base is connected to the body 2. In an unloaded or non-deflected state, the deflectable element 7 extends in the axial direction of the hub 4, for example, substantially parallel to the central longitudinal axis 5, from the base toward a second end of the hub 4. The height of the deflectable element 7 can vary in the tangential direction of the hub 4, measured from the base to the free end in the axial direction of the hub 4 (e.g., parallel to the central longitudinal axis 5). The varying height provides the inclined top surface 10 of the deflectable element 7 in the tangential direction of the hub 4 (i.e., around the central longitudinal axis 5 of the hub 4). Figure 1eThis can help apply force to the deflecting element 7 and deflect it, thereby increasing the stability of the bracket 1 in the axial and lateral directions during assembly, as will be discussed below.

[0040] Furthermore, in some embodiments, the free end of the deflectable element 7 can be positioned at least partially eccentrically about the central longitudinal axis 5 (i.e., at a different radial distance from the central longitudinal axis 5 of the hub 4). This also allows for the application of increased force to the deflectable element 7 and increases the stability of the bracket during assembly. The inclined top surface 10 and the eccentric position of the free end can be used in combination or separately, wherein each aspect increases the stability of the bracket 1 during assembly.

[0041] The top surface 10 of the free end of the deflectable element 7 can face away from the reference surface 6 and be inclined inward toward the central longitudinal axis 5. This provides reduced wear on the top surface 10 during assembly. Therefore, if the bracket 1 and retainer 20 are assembled and disassembled multiple times, the risk of material deformation or scratching of the top surface 10 is reduced and the shape of the top surface 10 is maintained, which also contributes to the consistent stability of the bracket during multiple assembly / disassembly. It also makes the assembly process easier and reduces friction between the mating surfaces of the components of the bracket 1 and retainer 20.

[0042] exist Figures 1a to 1e In one embodiment, the snap-fit ​​feature 9 includes a recess (e.g., a V-shaped recess) that extends from the free end 10 of the deflectable element 7 toward the first end of the hub 4. In other embodiments, the snap-fit ​​feature is a U-shaped recess. Other shapes are also foreseeable. For a V-shaped recess, the snap-fit ​​feature 9 includes two sides that can contribute to stability, as will be explained further below.

[0043] As disclosed above, the reference surface 6 is located at a first end of the hub 4 and radially positioned at a first distance from the central longitudinal axis 5, and the deflectable element 7 is located at a second end of the hub 4 and radially positioned at a second distance from the central longitudinal axis 5. In some embodiments, the first distance differs from the second distance. This increases the stability of the support because forces will be directed inward / outward from the deflectable element 7 toward the reference surface 6 relative to the central longitudinal axis 5. Figures 1a to 1e In the embodiment shown, the first distance is smaller than the second distance, which increases stability and allows for a compact design at the far end, wherein the bracket 1 and the retainer 20 are easy to assemble.

[0044] In some embodiments, the guide surface 8 includes a first portion and a second portion. The first portion may have a cylindrical cross-section along the axial direction of the hub 4, and the second portion may have a tapered cross-section along the axial direction of the hub 4, or vice versa. The shapes of the first and second portions may be complementary to the shapes of the mating surfaces of the retainer 20. The tapered cross-section increases stability because the bracket 1 is pushed toward the distal end of the retainer 20 during assembly, as will be discussed below, while the cylindrical cross-section ensures that the bracket 1 does not get stuck on the retainer 20 and thus provides easier disassembly.

[0045] As in Figure 1a As can be seen, the hub 4 may include at least one groove 11 having an open end facing the central longitudinal axis 5 and a closed end facing the periphery of the hub 4. The closed end may be positioned closer to the periphery of the hub 4 than at least a portion of the deflectable element 7. The groove 11 may extend through a guide surface 8, which is divided into multiple segments along the longitudinal axis of the hub 4. The groove 11 provides an inlet for a portion of the retainer 20, as will be described below. Figures 1a to 1e In one embodiment, the groove 11 includes side surfaces that extend from the open end to the closed end in the radial or lateral direction of the hub 4.

[0046] The stop member 12 may be located at the recess. The recess 9 may be located between the stop member 12 and the top surface 10 of the deflectable element 7. The height of the stop member 12 may be greater than the height of the top surface 10. Additionally, the thickness of the stop member may be greater than the thickness of the rest of the deflectable element 7. This provides a reduced deflectability of the deflectable element 7 at the stop member 12 compared to the opposite side of the deflectable element 7, which in turn can increase the force applied to the support 1 and enhance stability. Thus, the stop member 12 can have a dual function. However, in other embodiments, the stop member 12 may have the same thickness as the rest of the deflectable element 7.

[0047] In the illustrated embodiment, the base of the deflectable element 7 is attached to the base of the bracket 1 between the side surfaces adjacent to the slots 11. The slots 11 provide additional flexibility to the deflectable element 7 because, during assembly / disassembly, as the deflectable element 7 is pushed outward / inward, the portion of the base between the slots 11 can tilt / downward in the longitudinal direction of the hub 4. This further contributes to the stability of the bracket 1 and ease of assembly / disassembly.

[0048] The body 2 may have multiple arms positioned around the hub, each arm having a marking region 3. The number of arms and the distance between their lengths and the marking regions 3 can vary depending on the desired accuracy and the number of degrees of freedom to be tracked. In the illustrated embodiment, the number of arms is four, with a single marking region 3 at the tip of each arm. However, the number of arms, the number of marking regions 3 on each arm, and the pattern formed by these regions can be different. Figures 1a to 1e In the embodiments described, the exact shape of the arm and the pattern formed by region 3 are merely examples.

[0049] The material thickness of the base and hub 4 can be determined to provide deflection of the deflection element 7 as described herein, while the area 3 used for marking remains intact and does indeed move relative to the reference surface 6 during deflection. This provides a fixed relationship between each mark and the retainer 20 when the bracket 1 is mounted to the retainer. For example, the deflection of the free end 10 can be in the range of a few millimeters or less.

[0050] Retainer Figures 2a to 2c A retainer 20 is shown, for example, for a bracket 1 according to an embodiment described above. The retainer 20 is designed to have a shape at least partially complementary to the bracket 1, such that the bracket 1 can be stably mounted to the retainer 20. Thus, the retainer 20 can be permanently or removably mounted to other devices (e.g., instruments). Therefore, other devices can be accurately tracked in space by tracking the bracket. Mounting a retainer to other instruments is described, for example, by the applicant of this application in WO 2019 / 164441 (wherein the retainer is referred to as a “head”), which is incorporated herein by reference in its entirety.

[0051] The retainer 20 includes a protrusion 21 extending in the radial or transverse direction. The protrusion 21 may extend partially or completely around the circumference of the retainer 20. The protrusion 21 provides a support portion that, when the bracket 1 and the retainer 20 are assembled, the reference surface 6 may abut against and be positioned in a fixed, predetermined location. The protrusion 21 may be centered around the longitudinal axis 22 of the retainer. The size of the transverse extension of the protrusion 21 may be determined to have a width equal to or greater than the width of the reference surface 6 of the bracket 1.

[0052] The retainer 20 includes at least one arm 23 extending in a radial or transverse direction. A guide surface 24 extends at least partially between the protrusion 21 and the arm 23. The guide surface 24 of the retainer 20 may be centered about the longitudinal axis 22 of the retainer 20. Moreover, the size and shape of the guide surface 24 of the retainer may be determined to have a tight fit (e.g., a sliding fit or a positioning fit) with the guide surface 8 of the support 1. Thus, the guide surface 24 of the retainer 20 may include a first portion having a tapered cross section along the longitudinal axis 22 of the retainer 20, and a second segment having a cylindrical cross section along the longitudinal axis 22, and vice versa.

[0053] Arm 23 may be spaced apart from protrusion 21 along longitudinal axis 22 of retainer 20. Furthermore, arm 23 includes a sliding surface 25 that may be tilted in a non-perpendicular direction relative to the axial direction along longitudinal axis 22 of retainer 20. This provides a stable mounting of bracket 1 to retainer 20, as will be further described below.

[0054] The sliding surface 25 (e.g., its tip) can be rounded in the tangential direction of the retainer 20. Such a shape can be positioned within a U-shaped or V-shaped snap-fit ​​feature. The radius of the sliding surface 25 and the dimensions of the V-shaped recess 9 of the support 1 can be determined such that the sliding surface 25 abuts the side of the recess 9 rather than the tip of the sliding surface 25, which is spaced apart from the tip / deepest part of the recess 9. Therefore, the arm 23 will be supported by two separate surfaces, thereby increasing the stability of the assembly of the support 1 and the retainer 20.

[0055] Arm 23 may have a base and a free end. A sliding surface 25 may extend at least partially between the base and the free end and have a first region and a second region. The first region may be positioned closer to the base than the second region. A first axial distance, measured from the distal portion of the first region to the protrusion 21, may be shorter than a second axial distance, measured from the distal portion of the second region to the protrusion 21. In other words, the sliding surface 25 may be inclined relative to the transverse axis of the retainer (i.e., the axis perpendicular to the longitudinal axis 22 of the retainer 20). This inclination allows the base of arm 23 to be positioned closer to the protrusion 21 than the free end of arm 23. Furthermore, the sizes of the sliding surface 25 and the free end of the deflectable element may be determined such that when the bracket 1 and the retainer 20 are assembled, the sliding arm abuts the free end of the deflectable element. Therefore, when assembled with the retainer 20, the bracket 1 can be held between the sliding surface 25 and the protrusion 21. Furthermore, the distance between the sliding surface 25 and the protrusion 21 can be determined to be at least partially greater than the first distance between the reference surface 6 and the free end of the deflectable element 7 at the groove 11. The distance between the sliding surface 25 and the protrusion 21 can be less than the second distance between the reference surface 6 and the free end of the deflectable element 7 closer to the recess 9, or even the distance measured at the deepest point of the recess 9. This provides easy assembly of the bracket 1 and the retainer 20, while the deflectable element 7 can be deflected outward away from the central longitudinal axis 5 when the bracket 1 and the retainer 20 are assembled. In addition, deflecting the deflectable element 7 during assembly provides a force to the bracket 1, which enhances stability. However, it is not necessary to deflect the deflectable element 7 in all embodiments. Instead, a sliding fit or positioning fit can be provided between the sliding surface 25 and the deflectable element 7.

[0056] The sliding surface 25 may have a peak forming the distal portion of the first region and the distal portion of the second region. The peak may be straight between the first and second regions and may be inclined relative to the radial or lateral direction of the retainer 20. This provides reduced friction between the sliding surface 25 and the free end of the deflectable element 7 and reduces the risk of deformation and damage to the deflectable element 7, as discussed above.

[0057] The base 26 or distal end of the retainer 20 may be inclined relative to the longitudinal axis 22 and / or the protrusion 21, such as Figure 2b and Figure 2c The embodiment shown is as described above. However, in other embodiments, the base 26 or distal end of the retainer 20 may be parallel to the protrusion 21. Therefore, the marking area 3 may be parallel or inclined relative to the base 26 of the retainer 20.

[0058] The retainer 20 can be made of a material that is more rigid than the material of the support 1, such as titanium or stainless steel. Therefore, the arm 23 can be rigid and does not deflect with the deflectable element 7, as described herein.

[0059] Components with brackets and retainers To assemble the bracket 1 and retainer 20, the longitudinal axis of the bracket is aligned with the longitudinal axis 22 of the retainer 20. The retainer 20 is rotated about its longitudinal axis to align the slot 11 with the arm 23 of the retainer. The guide surface 8 of the bracket 1 is guided along the guide surface 24 of the retainer 20. The sizes of the guide surface 8 of the bracket 1 and the guide surface 24 of the retainer 20 are determined such that there is a gap between the arm 23 and the side surface of the slot. The bracket 1 is guided along the guide surface 24 of the retainer until the reference surface 6 abuts the protrusion 21 of the retainer 20. This provides a stable assembly in the axial direction of the bracket 1 and the retainer 20. The bracket 1 is then rotated relative to the retainer 20, wherein the sliding surface 24 abuts the free end of the deflection element 7. This provides a fixed position of the bracket 1 relative to the retainer in the axial direction of the assembly. The abutment / sliding fit or positioning fit between the guide surface 8 of the bracket 1 and the guide surface 24 of the retainer 20 prevents the bracket 1 from tilting relative to the retainer 20, i.e., provides stability in the direction transverse to the longitudinal axis of the assembly. The tighter the fit, the more stable the connection. Furthermore, when the free end of the deflectable element 7 is tilted and the sliding surface is tilted relative to the lateral axis of the retainer 20 (as described above), the deflectable element 7 deflects outward away from the longitudinal axis, thereby providing force from the arm 23 to the bracket 1, which is securely attached between the arm 23 and the protrusion 21, increasing stability in both the axial and lateral directions. The bracket 1 can be rotated until the arm engages with the snap-fit ​​feature 9 in the assembled position. In the assembled position, the distance between the arm 23 and the protrusion 21 can be determined such that the deflectable element 7 deflects outward. Therefore, force can also be provided in the position where the bracket 1 is fully assembled into the retainer 20, which further increases stability and prevents accidental disassembly. To remove the bracket 1 from the retainer 20, the process is reversed.

[0060] In the case where the bracket has multiple slots 11 and the retainer 20 has multiple arms, one or more slots 11 / arms 23 may have a wider width than the other slots 11 / arms 23, wherein the size of the wider arm 23 may be determined to have a gap with the correspondingly sized slot 11, but is too large for passage through at least one of the smaller slots 11. This provides for assembling the bracket 1 only in one rotational direction relative to the retainer 20.

[0061] As mentioned above, the bracket 1 may have one or more stop members 12, such as one stop member for each recess 9. The stop members prevent the arm 23 and sliding surface 24 from rotating too far beyond the recess 9 during assembly. The stop members 12 also prevent improper disassembly of the bracket 1 and retainer 20 by rotating the bracket 1 relative to the retainer 20 in the wrong direction. Furthermore, the stop members may be located on the side surface of the groove 11, for example, as an extension of the side surface. This provides protection against rotating the bracket 1 in the wrong direction during assembly, since the height of the stop members 12 is higher than the top surface 10 of the deflectable element 7.

[0062] exist Figures 1a to 1e as well as Figures 2a to 2c In the illustrated embodiment, the stent has three sets of deflecting elements 7, slots 11, guide surfaces 8, reference surfaces 6, and snap-fit ​​features 9, and the retainer 20 has a corresponding number of mating elements. This provides enhanced stability compared to a case with a single deflecting element 7, slot 11, guide surface 8, reference surface 6, and snap-fit ​​feature 9, and the retainer 20 having only one of each mating element. However, in some embodiments where lower accuracy is desired in navigation systems, embodiments with only one of each of these features provide sufficient accuracy. Embodiments with three sets are particularly useful where high accuracy (e.g., sub-millimeter) is desired. The stent 1 and retainer 20, as described herein, with positioning and / or sliding mating, are designed to provide stability, thereby achieving accuracy in the low sub-millimeter range for navigation systems (e.g., optical navigation systems for surgical navigation). Such systems can be used to navigate instruments and implants with corresponding accuracy relative to the patient's anatomy.

[0063] As will be apparent, the features and attributes of the specific embodiments disclosed above can be combined in different ways to form additional embodiments, all of which fall within the scope of this disclosure.

[0064] Unless expressly stated otherwise, or otherwise understood in the context in which they are used, the conditional language used herein (e.g., in particular “can,” “could,” “might,” “may,” “for example,” etc.) is generally intended to convey that certain embodiments include certain features, elements, and / or states that are not included in other embodiments. Therefore, such conditional language is not generally intended to imply that features, elements, and / or states are required in any way for one or more embodiments, or that one or more embodiments necessarily include logic for determining (with or without author input or prompting) whether such features, elements, and / or states are included or will be performed in any particular embodiment.

[0065] Any process descriptions, elements, or blocks depicted in the flowcharts described herein and / or the accompanying drawings should be understood to potentially represent modules, segments, or code portions that include one or more executable instructions for implementing specific logical functions or steps in the process. Alternative implementations are included within the scope of the embodiments described herein, wherein, as those skilled in the art will understand, depending on the functionality involved, elements or functions may be omitted, or elements or functions may be performed out of order shown or discussed, including substantially simultaneously or in reverse order.

[0066] It should be emphasized that many changes and modifications can be made to the embodiments described herein, and elements of these embodiments will be understood to exist in other acceptable examples. All such modifications and variations are intended to be included within the scope of this disclosure and protected by the following claims.

[0067] The present invention has been described above with reference to specific embodiments. However, other embodiments besides those described above are also possible within the scope of the present invention. Method steps different from those described above can be provided within the scope of the present invention. Different features and steps of the present invention can be combined with combinations different from those described. The scope of the present invention is limited only by the appended claims.

Claims

1. A bracket for at least one marker in a navigation system, the bracket comprising: The body having at least one region for the at least one mark; as well as Hub, used for attaching the bracket to the retainer, the hub comprising: A central longitudinal axis that defines the axial direction of the hub; At least one reference surface, the at least one reference surface being located at a first end of the hub and radially positioned at a first distance from the central longitudinal axis; At least one deflectable element is located at the second end of the hub and radially positioned at a second distance from the central longitudinal axis; At least one guiding surface, the at least one guiding surface extending at least partially between the reference surface and the deflectable element; and A snap-fit ​​feature, located at the deflectable element, and At least one groove having an open end toward the central longitudinal axis and a closed end toward the periphery of the hub, wherein the closed end is positioned closer to the periphery of the hub than at least a portion of the deflectable element, wherein the groove includes a side surface extending from the open end to the closed end in the radial or lateral direction of the hub.

2. The stent according to claim 1, wherein, The deflectable element has a base and a free end, the base being connected to the body, and the deflectable element extending in the axial direction of the hub.

3. The stent according to claim 2, wherein, The height of the deflectable element varies in the tangential direction of the hub, and the height is measured in the axial direction of the hub from the base to the free end.

4. The stent according to any one of the preceding claims, wherein, The free end of the deflectable element is at least partially eccentrically positioned around the central longitudinal axis.

5. The stent according to claim 4, wherein, The top surface of the free end faces the reference surface and is inclined toward the central longitudinal axis.

6. The stent according to claim 1, wherein, The snap-fit ​​feature includes a V-shaped recess.

7. The stent according to claim 1, wherein, The first distance is different from the second distance.

8. The stent according to claim 7, wherein, The first distance is smaller than the second distance.

9. The stent according to claim 1, wherein, The guide surface includes a first portion and a second portion, the first portion having a cylindrical cross-section in the axial direction of the hub, and the second portion having a tapered cross-section in the axial direction of the hub.

10. The stent according to claim 1, wherein, The body includes multiple arms positioned around the hub, each arm having a marking area.

11. A retainer for a support according to any one of claims 1 to 10, the retainer comprising: A protrusion that extends in the lateral direction of the retainer; At least one arm, which extends in the lateral direction of the retainer; as well as A guide surface that extends at least partially between the protrusion and the arm; wherein, The arm is spaced apart from the protrusion; and The arm includes a sliding surface that is inclined in a non-perpendicular direction relative to the axial direction of the retainer.

12. The retainer according to claim 11, wherein, The sliding surface is circular in the tangential direction of the retainer.

13. The retainer according to claim 12, wherein, The arm has a base and a free end, and the sliding surface extends at least partially between the base and the free end and has a first region and a second region, the first region being positioned closer to the base than the second region, and wherein a first axial distance is shorter than a second axial distance, the first axial distance being measured from the distal portion of the first region to the protrusion, and the second axial distance being measured from the distal portion of the second region to the protrusion.

14. The retainer according to claim 13, wherein, The sliding surface has a peak that forms the distal portion of the first region and the distal portion of the second region, and wherein the peak is straight between the first region and the second region and is inclined relative to the lateral direction of the retainer.

Images