Registration device and registration method

Abstract

The present invention relates to a registration device (2) for registering at least two bones (K1, K2, K3), the registration device comprising: at least two bone anchors (4), wherein each of the bone anchors (4) has a fastening portion (6), which is designed to be rigidly attached to one of the bones (K1, K2, K3) in each case, and a bone tracker (8), which has an individual optical pattern (10) designed for tracking; a temporary fastening device (12), wherein the fastening device (12) is designed to rigidly interconnect the bone anchors (4); and a registration element (18), wherein the registration element (18) is designed to be rigidly connected to one of the bone anchors and comprises a plurality of radiopaque markers (20) and an optical pattern (22) that is designed for tracking. The present invention also relates to a method for registration using the registration device (2).

Description

[0001] Registration device and registration procedure

[0002] Description

[0003] Technical field

[0004] The present disclosure relates to a registration device and a (computer-implemented) registration method for registering at least two bones.

[0005] It is known from the state of the art to use advanced imaging techniques, such as CT scans (or MRI scans or other radiological image data), for bone registration, for example in the field of spinal surgery. Image data is processed using image processing algorithms, either by performing an intraoperative 3D CT scan or by linking or combining an intraoperative 2D scan with anterior-posterior and lateral orientation with a preoperative 3D scan. Depending on the technology used and the design of the navigation and imaging system, a registration device (or tracker) must be attached to the vertebra or the corresponding bone for the intraoperative scan. The registration device must contain radiopaque markers so that it can be detected in the CT scan.This procedure must be performed according to current technological standards for the registration of each individual bone.

[0006] From WO 2016 / 044 934 A1, such a method for the intraoperative registration of surface data with volumetric image data is known, wherein the method comprises: acquiring signals with a tracking system, wherein the signals are associated with reference markers located on a tracking marker carrier structure, the tracking marker carrier structure being detachably attached to a skeletal feature of a subject in a preselected orientation relative to the skeletal feature; processing the signals and using the preselected orientation to determine an intraoperative reference direction associated with an intraoperative position and orientation of the subject; intraoperatively acquiring the surface data from a surgical region of interest; and using the intraoperative reference direction when registering the surface data onto the volumetric image data.

[0007] In many applications, registration is not performed for each individual bone because it is both time-consuming and physically demanding, and each registration involves a 3D CT scan and thus radiation exposure. For this reason, in spinal surgery, for example, registration is not performed individually for each bone. Instead, adjacent vertebrae are instrumented / operated on using an imaging technique without moving a tracker or performing a new registration. However, this can lead to inaccuracies in vertebral instrumentation and complications because the spine is not a rigid bone but is flexible due to the intervertebral discs.

[0008] Furthermore, it is known from EP 3494 903 B1 to connect several bones together and to register and track these connected bones together. However, a disadvantage of this method is that the rigid connection between the bones must be maintained and the bones cannot be tracked individually. Therefore, in particular, tracking of the individual bones for relative positioning to each other is not possible.

[0009] The object of this disclosure is therefore to avoid or at least reduce the disadvantages of the prior art. In particular, a registration device and a method for registering at least two bones, especially those movable relative to each other, are to be provided, in which individual (i.e., independent) registration of several bones is possible simply and quickly to enable precise tracking of the multiple bones. The object of this disclosure is achieved by a registration device with the features of claim 1 and by a method with the features of the dependent claim.

[0010] Accordingly, the present disclosure relates to a registration device for registering at least two bones. The disclosure is not limited to a registration device for registering (only) two bones or bone sections or bone fragments, but can serve to register three, four, five, six, or more bones or bone sections or bone fragments. The registration device is particularly suitable for the simultaneous registration of the bones. The bones can, in particular, be movable relative to one another, i.e., not be sections of a rigid bone. The registration device is particularly suitable for use in surgery, preferably spinal surgery. The registration device can alternatively or additionally be used in oral and maxillofacial surgery or in orthopedics or orthopedic surgery.In particular, the registration device can be used when several bones or bone fragments are movable relative to each other and positioning or instrumentation of the individual bones or bone fragments is required.

[0011] The registration device has at least two bone anchors. In particular, the registration device has a number of bone anchors corresponding to the number of bones. Each of the (at least two) bone anchors has a (distal) attachment section. The attachment section is designed to be rigidly attached to each of the (to be registered) bones. This means that, in particular, at least one bone anchor (for example, exactly one bone anchor or two or more bone anchors) can be attached to or is attached to each bone. Each of the (at least two) bone anchors has a (proximal) bone tracker. The bone tracker has an individual optical pattern that is designed for (optical) tracking (or, in particular, for being tracked). "Individual" means that the respective optical patterns of the different bone trackers or bone anchors are different from each other.The optical patterns must be distinguishable or uniquely identifiable. It is sufficient if the optical patterns differ with respect to at least one so-called feature (preferably a few, for example, fewer than five features) from a total number of features (for example, 20 to 200) per optical pattern.

[0012] The registration device includes a temporary fastening device. This fastening device is designed to rigidly connect the bone anchors. It can be configured to connect (only / exactly) two bone anchors at a time, or it can be configured to connect more than two bone anchors using multiple fastening devices. The fastening device can also be configured to connect more than two bone anchors (for example, three, four, or five). In particular, the fastening device is designed to allow the bone anchors to be reconnected, preferably easily and quickly, and in a releasable manner. The fastening device is specifically designed to firmly connect the essentially parallel or skew-aligned rods / pins of the bone anchors.For example, the fastening device can have two clamping and / or gripping sections, preferably diametrically opposed and each movable, for rigid attachment to one of the bone anchors, as well as a locking section, preferably manually operated, for locking the position of the clamping and / or gripping sections. Since the fastening device serves only for the temporary fixation of the bones during registration, it only needs to exert minimal holding forces, as during registration it primarily needs to prevent relative movement of the bones or bone anchors relative to each other, such as that caused by breathing.

[0013] The registration device comprises a registration body. The registration body is designed to be rigidly connected to one of the bone anchors. The registration body can be rigidly connected to the bone anchor, for example, by spring-loaded pins or a clamp. The registration body features a multitude of radiopaque markers and an optical pattern designed for tracking (or, in particular, being tracked). Apart from the radiopaque markers, the registration body can be made of a radiolucent material.

[0014] The core of the disclosure consists in the fact that the registration device is set up to temporarily rigidly connect several (relatively movable) bones together during registration, so that the bones are registered as a rigid whole bone, can be delimited from each other by segmenting the CT scan, and the delimited bones can be assigned to individual trackers (connected to the respective bone), whereby the registration of the rigid whole bone in the temporarily rigidly connected state is transformed onto the individual trackers.

[0015] This has the advantage that each bone can be individually tracked in a single registration process, reducing radiation exposure and time. Furthermore, accuracy is improved, and individual bone tracking reduces complications during surgery. Combined with an innovative tracker size, the registration device is particularly advantageous for minimally invasive surgical procedures.

[0016] Preferably, the registration body can have a size / area defined / spanned by the radiopaque markers that essentially corresponds to the size of the bones to be registered and / or is significantly larger than, for example, 3, 5, 10, 15, or 20 times the size / area defined / spanned by the bone tracker (or the optical pattern of a bone tracker). Such dimensions ensure sufficient accuracy during registration.

[0017] Preferably, the registration body can be disc-shaped and have the optical pattern on its surface (i.e., a top or bottom surface of the disc). The registration body can preferably have at least two (or a number corresponding to the number of bone anchors) through-openings, each of which passes through one of the bone anchors. The through-openings can, for example, be closed on their circumference (e.g., closed round or closed slit-like) or open to one side of the registration body (e.g., slit-like and open on one side). The through-openings are preferably dimensioned and arranged such that the bone anchors can be positioned relative to the registration body with essentially no force exerted, i.e., essentially without contact.This means that the bone anchors must extend through the openings in such a way that their alignment is not affected. In particular, the bone anchors must not be subjected to tension or similar stresses by the registration body.

[0018] A rigid connection / attachment / fastening is understood to mean, in particular, that there is no degree of freedom between the respective connecting partners, i.e., between the bone and the bone anchor, or between the at least two bone anchors, or between the registration body and one of the bone anchors. This means that the respective connecting partners are in a fixed geometric relationship to each other, and no relative movement between the connecting partners is possible.

[0019] As an alternative to tracking via the optical patterns (of the registration body and / or the bone trackers), another optical tracking method can be used, such as electromagnetic tracking.

[0020] As an alternative to directly attaching the bone anchors to the bone, the bone anchors (or the attachment sections) can also be designed to be attached to an implant already implanted on / in the bone.

[0021] According to a preferred embodiment, the registration device can include a control unit. The control unit can be configured to transform a registration of the registration body as a patient tracker to the bone trackers as individual patient trackers. That is, (when registering the registration body as a patient tracker) the pose of the radiopaque markers (and thus of the registration body) is linked to radiological image data, in particular CT 3D image data of the bones, and in turn, the pose of the registration body (and thus of the optical pattern of the registration body) is linked to the poses of the optical patterns of the bone trackers (and thus of the bone anchors). That is, through the registration transfer, the bones (as a rigid unit) – as long as they are rigidly connected to each other via the bone anchors and the temporary fixing device – are linked via each of the optical patterns (i.e.,are traceable via the optical pattern of the registration body and each individual optical pattern of the bone trackers).

[0022] According to a preferred embodiment, the registration device can include an image processing device. The image processing device can be configured to segment the bones in a 3D CT scan. The image processing device can be configured to assign the segmented bones to the respective bone anchors designed for rigid attachment. This means that, through segmentation in the radiological image data, particularly CT 3D image data, the individual bones are extracted from the rigid unit of bones. By assigning each bone to a bone anchor (connected to the corresponding bone), the individual or segmented bones can be tracked independently of the other bones—even after the temporary attachment device has been released—using the respective bone tracker rigidly attached to it or the optical pattern of the bone tracker.

[0023] According to a preferred embodiment, the registration device may include a navigation camera. The navigation camera may be configured to track the optical pattern of the registration body and / or the optical patterns of the bone anchors. The navigation camera may, in particular, be a white light camera or an infrared camera.

[0024] According to a preferred embodiment, the navigation camera can be movably arranged relative to the registration body and / or the bone anchors, in particular by means of a robotic arm. This increases the accuracy of the data acquisition. The movement of the navigation camera can be performed at low speed and / or automatically.

[0025] According to a preferred embodiment, the registration device can be a component of a robotic system. The robotic system can, in particular, comprise a robotic base and a robotic arm movably mounted on the robotic base. The robotic arm can have an end effector on which the navigation camera is arranged. The robotic system can, in particular, comprise a robotic cart, preferably with a monitor. The navigation camera can be arranged on the robotic cart. Preferably, the robotic system can comprise a surgical visualization system, such as an exoscope. The navigation camera can be formed by the exoscope or be a separate camera, for example, arranged adjacent to the exoscope. The robotic system can comprise a pre-operative planning unit configured to automatically move the navigation camera (which is, in particular, mounted on the robotic arm / end effector).

[0026] According to a preferred embodiment, the X-ray-tight markers and the optical pattern of the registration body can be configured for detection in different wavelength ranges. This allows different detection modalities to be combined.

[0027] According to a preferred embodiment, the radiopaque markers and the optical patterns of the bone trackers can be configured for detection in different wavelength ranges. This allows different detection modalities to be combined.

[0028] According to a preferred embodiment, the radiopaque markers can be configured for detection in the X-ray spectrum. This means that the radiopaque markers are visible in the CT scan. According to a preferred embodiment, the optical pattern of the registration body can be configured for detection in the visible and / or infrared spectrum. This allows the use of standard navigation cameras.

[0029] According to a preferred embodiment, the optical patterns of the bone trackers can be configured for detection in the visible spectrum and / or the infrared spectrum. This allows the use of conventional navigation cameras.

[0030] An optical pattern can be understood, in particular, as a pattern that exhibits different sections in at least two different colors, e.g., black and white, or with contrast. Specifically, the optical pattern cannot be an IR marker. The optical pattern can be two-dimensional or applied to a surface. The optical pattern can be in the form of regularly or irregularly arranged lines (like a barcode), squares (like a QR code), and / or circles / ellipses. The optical pattern can be a machine-readable code.

[0031] According to a preferred embodiment, the registration body can have a preferably flat outer surface, and the optical pattern of the registration body can be applied (planarly) to the outer surface. This means that the optical pattern is preferably two-dimensional and not formed by a three-dimensional arrangement.

[0032] According to a preferred embodiment, the bone trackers can have a preferably flat outer surface, and the optical patterns of the bone tracker can be applied (planarly) to the outer surface. This means that the optical patterns are preferably two-dimensional and not formed by a three-dimensional arrangement.

[0033] According to a preferred embodiment, the geometric positioning between the radiopaque markers and the optical pattern of the registration body can be fixed and known. Thus, the positions can be linked (via a transformation) and easily converted (via the transformation), so that it is sufficient to determine only the radiopaque markers or only the optical pattern of the registration body.

[0034] According to a preferred embodiment, the geometric positioning between the optical pattern of the registration body and the optical patterns of the bone trackers can be unchanging in the fixed state of the temporary fixation device. Thus, the positions in the fixed state of the temporary fixation device can be linked (via a transformation) and easily converted (via the transformation).

[0035] According to a preferred embodiment, the temporary mounting device can be arranged distal to the registration body. This means that the temporary mounting device is positioned closer to the two bone anchors than the registration body. Thus, the registration body is positioned above the temporary mounting device, so that no visibility problems arise for the navigation camera.

[0036] According to a preferred embodiment, the optical pattern of the registration body can be arranged distal to the optical patterns of the bone trackers. This means that the optical pattern of the registration body is positioned closer to the two bone anchors than the optical patterns of the bone trackers. Thus, the optical patterns of the bone trackers are not obscured by the optical pattern of the registration body.

[0037] According to a preferred embodiment, the optical pattern of the registration body and / or the optical patterns of the bone trackers can be oriented away from the bone anchors. This means that the optical pattern(s) are oriented towards the navigation camera for capturing the optical pattern(s), with the navigation camera being positioned on a side of the registration body or bone trackers facing away from the bone trackers. According to a preferred embodiment, an arrangement of the radiopaque markers of the registration body may be known such that a pose of the registration body can be determined based on the radiopaque markers. This means that the radiopaque markers and the dimensions of the registration body are in a (known) fixed geometric relationship to each other.

[0038] According to a preferred embodiment, the arrangement of the optical pattern of the registration body can be known such that a pose of the registration body can be determined based on the optical pattern of the registration body. That is, the optical pattern of the registration body and the dimensions of the registration body are in a (known) fixed geometric relationship to each other.

[0039] According to a preferred embodiment, the arrangement of the optical pattern of the respective bone anchor can be known such that a pose of the respective bone anchor can be determined based on the optical pattern of the respective bone anchor. This means that the optical pattern of the respective bone anchor or bone tracker and the dimensions of the bone anchor are in a (known) fixed geometric relationship to each other.

[0040] According to a preferred embodiment, each bone tracker can be detachably and reproducibly connected to the mounting section in a fixed geometric relationship. In particular, the bone tracker can have a hole and be attached to the mounting section or a connecting section of the bone anchor (transitioning into the mounting section). For example, the mounting section or the connecting section can form an anti-rotation section for connecting the bone tracker in a rotationally fixed manner and / or an axial stop for axially positioning the bone tracker. This means that the bone tracker (and thus also the optical pattern of the bone tracker) and the mounting section are in a (known) fixed geometric (relative) relationship when connected.According to an alternative embodiment, the bone tracker can be permanently connected to the attachment section in a fixed geometric relationship, in particular, it can be integrally formed with the attachment section. This means that the optical pattern can, for example, be applied directly to a proximal section of the bone anchor. The permanent or integral design ensures that the bone tracker (and thus also the optical pattern of the bone tracker) and the attachment section are in a (known) fixed geometric (relative) relationship.

[0041] According to a preferred embodiment, each bone anchor can have a rod-shaped or pin-shaped (essentially continuous circular cylindrical in cross-section) base body. At a distal end of the base body, the fastening section, in particular in the form of a threaded section or a clamping section, can be formed. At a proximal end of the base body, the respective bone tracker can be connected to or attached to the base body. The base body can form the connecting section between the fastening section and the bone tracker. For example, the rod-shaped or pin-shaped base body can have a diameter in the millimeter range, approximately 1.5 mm, 2 mm, 2.5 mm, or 3 mm. This ensures that a stable connection can be established with minimal impact on the bone. For example, the rod-shaped or pin-shaped base body can have a diameter in the millimeter range, approximately 1.5 mm, 2 mm, 2.5 mm, or 3 mm.The pin-shaped base bodies have a length in the low centimeter range, approximately 5 cm, 6 cm, 8 cm, 10 cm, or 12 cm. This ensures that a patient, particularly in spinal surgery, can be positioned within a standard CT scanner using the bone anchors attached to the bone.

[0042] According to a preferred embodiment, each bone anchor can have a plurality of radiopaque markers. In particular, the bone tracker and / or the rod-shaped base body can have the plurality of radiopaque markers. This may increase the accuracy during registration.

[0043] The present disclosure also relates to a (computer-implemented) method for registering at least two bones, in particular bones movable relative to each other, especially with a registration device as disclosed. The method comprises the following steps:

[0044] - Creating a 3D CT scan of the bones, the bone anchors rigidly attached to the bones, and the registration body rigidly connected to one of the bone anchors, especially while the bone anchors are rigidly connected to each other;

[0045] - Segmenting the bones in the 3D CT scan;

[0046] - Detecting the radiopaque markers of the registration body and determining a pose of the registration body based on the radiopaque markers;

[0047] - (Optical) detection of the optical pattern of the registration body and determination of a pose of the registration body based on the optical pattern,

[0048] - (Optical) detection of the optical patterns of the bone trackers and determination of a pose of the respective bone anchor;

[0049] - Transforming the pose of the registration body determined by the radiopaque markers to the poses of the bone anchors determined by the optical patterns of the bone trackers, while the bone anchors are rigidly connected to each other; and

[0050] - Assigning the segmented bones to the pose of the respective bone anchor attached to the bone.

[0051] According to a preferred embodiment, the registration body can be detached from the bone anchor after transformation and assignment. This has the advantage that the view is not obstructed by the registration body.

[0052] According to a preferred embodiment, the bone anchors can be detached from each other after transformation and assignment. This has the advantage that the bone anchors can move relative to each other again, so that they can be positioned relative to each other – particularly when tracked.

[0053] According to a preferred embodiment, the optical pattern of the registration body and / or the optical patterns of the bone trackers can be captured from different angles and / or by a moving camera, in particular the navigation camera. This increases the accuracy of the capture.

[0054] In other words, this disclosure relates to a multi-level bone registration system that allows for the simultaneous registration of multiple bones, enabling the simultaneous determination of their position and orientation. This allows for intraoperative surgical tracking. This multi-level bone registration system utilizes individual bone anchors, a temporary fixation device, and a registration body with radiopaque markers and connected individual patient trackers. Several steps are necessary for registration. First, the bone anchors must be rigidly fixed to the bones (eliminating all six degrees of freedom), as otherwise accurate registration and subsequent tracking would be impossible.A temporary fixation between the bone anchors is then required to eliminate any movement between the bones during registration (e.g., due to patient breathing). A registration body containing radiopaque markers is then rigidly attached to one of the bone anchors. This registration body must also be trackable by a navigation camera, for which purpose it features an optical pattern on its upper surface. Next, the bone trackers are attached to the bone anchors. These, too, are trackable via an optical pattern. Following a 3D CT scan, this radiological image data is used to capture the radiopaque markers within the registration body. After a scan with a navigation camera, all trackers are captured. This means that the pose of the registration body and the poses of each individual bone tracker are calculated.A transformation then takes place between the registration body and the individual bone trackers. This is only possible because they are rigidly connected, preventing any movement between the bones during this transformation. Furthermore, the individual bones (especially before the transformation) have been segmented so that each bone tracker can be assigned to a specific bone. After the transformation, the registration body can be removed. The temporary fixation between the bone anchors can also be removed or retained, depending on the surgeon's preference.

[0055] Brief description of the characters

[0056] Figures 1 to 3 show a registration device according to the present disclosure;

[0057] Fig. 4 shows a robot system with the registration device;

[0058] Fig. 5 shows a schematic representation of a method for registration according to the present disclosure;

[0059] Fig. 6 shows a schematic representation of a preparatory procedure; and

[0060] Figures 7 to 10 show individual steps of the preparatory procedure.

[0061] Description of a preferred embodiment

[0062] A preferred embodiment of the present disclosure is described below on the basis of the associated figures.

[0063] Fig. 1 shows a perspective view of the recording device 2 according to the present disclosure. Fig. 2 shows a top view of the recording device 2. Fig. 3 shows a radiological view of the recording device 2.

[0064] The registration device 2 is for registering at least two bones and, in the illustrated embodiment, three bones K1, K2, K3. In the illustrated embodiment, the bones K1, K2, K3 are vertebrae of a spine. The bones K1, K2, K3 are, in particular, bones that can generally move relative to each other, but in the illustrated embodiment are (already) temporarily fixed.

[0065] The registration device 2 has at least two bone anchors 4. In particular, the registration device 2 has a number of bone anchors 4 corresponding to the number of bones, i.e., in the illustrated embodiment, three bone anchors 4.

[0066] Each of the bone anchors 4 has a (distal) attachment section 6. The attachment section 6 is designed to be rigidly attached to each of the (to be registered) bones K1, K2, K3. That is, a first bone anchor 4 is attached to bone K1, a second bone anchor 4 to bone K2, and a third bone anchor 4 to bone K3.

[0067] Each of the bone anchors 4 has a (proximal) bone tracker 8. The bone tracker 8 has an individual optical pattern 10, which is configured for (optical) tracking (or, in particular, for being tracked). This means that the optical pattern 10 of the first bone anchor 4 is different from the optical pattern 10 of the second bone anchor 4 and the third bone anchor 4, and vice versa. For example, the optical patterns 10 can differ in one or more features. In the illustrated embodiment, the optical patterns 10 are arranged in a checkerboard pattern. However, the optical patterns 10 can also be in the form of a QR code or another optically trackable pattern.In particular, the design and arrangement of the optical pattern 10 of the respective bone anchor 4 may be known, such that a pose of the respective bone anchor 4 can be determined based on the optical pattern 10 of the respective bone anchor 4.

[0068] Preferably, the bone tracker 8 can be detachably and reproducibly connected or attached to the mounting section 6 in a fixed geometric relationship. In particular, the bone tracker 8 can have a hole and be plugged onto the mounting section 8.

[0069] Preferably, the bone anchor 4 can have a rod-shaped or pin-shaped (essentially continuous circular cylindrical cross-section) base body 7. At a distal end of the base body 7, the fastening section 6, in particular in the form of a threaded section or a clamping section, can be formed. At a proximal end of the base body 7, the (respective) bone tracker 8 can be connected to or attached to the base body 7.

[0070] The registration device 2 has a temporary fastening device 12. The fastening device 12 is designed to rigidly connect the bone anchors 4 to one another. In the illustrated embodiment, two bone anchors 4 are connected to one another via a temporary fastening device 12. However, three bone anchors 4 can also be connected via the temporary fastening device 12. The fastening device 12 is specifically designed to rigidly connect substantially parallel or skew-aligned bone anchors 4 to one another.

[0071] For example, the fastening device 12 can have two, in particular diametrically opposed, preferably each movable open and closed clamping and / or gripping sections 14 for rigid fastening to each of the bone anchors 4 and a locking section 16, in particular manually operable, for locking a position of the clamping and / or gripping sections 14.

[0072] The registration device 2 has a registration body 18. The registration body is designed to be rigidly connected to one of the bone anchors 4 (here, the middle of the three bone anchors 4). The registration body 18 can be rigidly connected to the bone anchor 4, for example, by means of spring-loaded pins or a clamp.

[0073] The registration body 18 has a plurality of radiopaque markers 20. In particular, the design and arrangement of the radiopaque markers 20 may be known such that a pose of the registration body 18 can be determined based on the radiopaque markers 20. The registration body 18 can (apart from the radiopaque markers 20) be made of a radiolucent material (see Fig. 3).

[0074] The registration body 18 has an optical pattern 22 which is designed for tracking (or, in particular, for being tracked). In particular, a design and an arrangement of the optical pattern 22 of the registration body 18 may be known such that a pose of the registration body 18 can be determined from the optical pattern 22 of the registration body 18.

[0075] The registration body 18 can have a size / area defined / spanned by the radiopaque markers 20, which essentially corresponds to a size of the bones K1, K2, K3 to be registered and / or is significantly larger than, for example, 3, 5, 10, 15 or 20 times larger than a size / area defined / spanned by the bone tracker 8 or the optical pattern 10 of a bone tracker 8.

[0076] The registration body 18 can be disk-shaped. The registration body 18 can have the optical pattern 22 on its surface (i.e., a top or a bottom of the disk).

[0077] The registration body 18 may preferably have at least two (or a number corresponding to the number of bone anchors 4, i.e., three in this case) through-openings 24, through which one of the bone anchors 4 extends. The through-openings 24 may, for example, be closed on their circumference. Alternatively, the through-openings 24 may be open towards one side of the registration body 18.

[0078] The registration device 2 can include a control unit 26. The control unit 26 can be configured to transform a registration of the registration body 18 as a patient tracker to the bone trackers 8 as individual patient trackers.

[0079] The registration device 2 can include an image processing device 28. The image processing device 28 can be configured to segment the bones K1, K2, K3 in a 3D CT scan. The image processing device 28 can be configured to assign the segmented bones K1, K2, K3 to the respective bone anchor 4 designed for rigid attachment to them.

[0080] The registration device 2 may include a navigation camera 30. The navigation camera 30 may be configured to track the optical pattern 22 of the registration body 18 and / or the optical patterns 10 of the bone anchors 8. The navigation camera 30 may, in particular, be a white light camera or an infrared camera.

[0081] In particular, the registration device may be a component of a robot system 32 (see Fig. 4). The robot system 32 may, in particular, comprise a robot base 34 and a robot arm 36 movably connected to the robot base 34. The robot arm 36 may have an end effector 38 on which the navigation camera 30 is arranged. The robot system 32 may, in particular, have a robot cart 40, preferably with a monitor 42. The navigation camera 30 may be arranged on the robot cart 40. Preferably, the robot system 32 may comprise a surgical visualization system, such as an exoscope. The navigation camera 30 may be formed by the exoscope or be a separate camera, for example, arranged adjacent to the exoscope. The robot system 32 may have a pre-operative planning unit configured to automatically move the navigation camera 30 (in particular, mounted on the robot arm 36 / end effector 38).

[0082] Furthermore, the robot system 32 can have a CT arm 43 configured to create a 3D CT scan of the bones K1, K2, K3, the bone anchors 4 rigidly attached to the bones K1, K2, K3, and the registration body 18 rigidly connected to one of the bone anchors 4. The present disclosure also relates to a method 44 for registering at least two bones, in particular bones movable relative to each other, especially with a registration device as disclosed. The method 44 comprises the following steps (see Fig. 5):

[0083] Procedure 44 includes a first step S1: creating a 3D CT scan of the bones K1, K2, K3, the bone anchors 4 rigidly attached to the bones K1, K2, K3, and the registration body 18 rigidly connected to one of the bone anchors 4, while the bone anchors 4 are rigidly connected to each other. The 3D CT scan can be created, in particular, using the CT scanner 43.

[0084] Prior to step S1 of method 44 according to the present disclosure, a method 46 (see Fig. 6) can be carried out: In step VS1, the bone anchors 4 are attached to the bones K1, K2, K3 (see Fig. 7). In step VS2, the bone anchors 4 are rigidly connected to each other via the temporary fastening device 12 (see Fig. 8). In step VS3, the bone anchors 4 are rigidly connected to the registration body 18 (see Fig. 9). In step VS3, the bone trackers 8 are connected to the fastening sections 6 (see Fig. 10). This means that method 44 according to the present disclosure does not contain any surgical steps.

[0085] Method 44 includes a second step S2: segmenting the bones K1, K2, K3 in the 3D CT scan. Segmentation can be performed, in particular, by the image processing device 28.

[0086] Method 44 includes a third step S3: acquiring the radiopaque markers 20 of the registration body 18 and determining a pose of the registration body 18 based on the radiopaque markers 20. The acquiring can be performed, in particular, by the CT arm 43. The determining of the pose can be performed, in particular, by the control unit 26. Method 44 includes a fourth step S4: (optically) acquiring the optical pattern 22 of the registration body 18 and determining a pose of the registration body 18 based on the optical pattern 22. The acquiring can be performed, in particular, by the navigation camera 30. The determining of the pose can be performed, in particular, by the control unit 26 (and / or the navigation camera 30).

[0087] Preferably, the optical pattern 22 of the registration body 18 can be detected from different angles and / or during a movement of a camera performing the detection or by a moving camera, in particular the navigation camera 30.

[0088] Procedure 44 includes a fifth step S5: (optical) acquisition of the optical patterns 10 of the bone trackers 8 and determination of a pose of the respective bone anchor 4 based on the optical patterns 10. The acquisition can be performed in particular by the navigation camera 30. The determination of the pose can be performed in particular by the control unit 26 (and / or the navigation camera 30).

[0089] Preferably, the optical patterns 10 of the bone trackers 8 can be captured from different angles and / or during a movement of a camera performing the capture or by a moving camera, in particular the navigation camera 30.

[0090] Procedure 44 includes a sixth step S6: transforming the pose of the registration body 18, determined by the radiopaque markers 20, into the poses of the bone anchors 4, determined by the optical patterns 10 of the bone trackers 8, while the bone anchors 4 are rigidly connected to each other. This transformation can be performed, in particular, by the control unit 26.

[0091] Procedure 44 includes a seventh step S7: assigning the segmented bones K1, K2, K3 to the pose of the respective bone anchor 4 attached to bone K1, K2, K3. This assignment can be performed, in particular, by the control unit 26. Procedure 44 may include an eighth step S8: releasing the registration body 18 from the bone anchor 4 after transformation and assignment.

[0092] Procedure 44 may include an eighth step S8: releasing the bone anchors 4 after transforming and matching them to each other.

Claims

Claims 1. Registration device (2) for registering at least two bones (K1, K2, K3), comprising at least two bone anchors (4), each of the bone anchors (4) comprising a fastening section (6) configured to be rigidly attached to each of the bones (K1, K2, K3), and a bone tracker (8) with an individual optical pattern (10) configured for tracking, a temporary fastening device (12) wherein the fastening device (12) is configured to rigidly connect the bone anchors (4) together, and a registration body (18) wherein the registration body (18) is configured to be rigidly connected to one of the bone anchors (4), and comprising a plurality of radiopaque markers (20) and an optical pattern (22) configured for tracking.

2. Registration device (2) according to claim 1 , characterized by a control unit (26) which is configured to transform a registration of the registration body (18) as a patient tracker to the bone trackers (8) as individual patient trackers.

3. Registration device (2) according to claim 1 or 2, characterized by an image processing device (28) which is configured to segment the bones (K1 , K2, K3) in a 3D CT scan and to assign them to the respective bone anchor (4) configured for rigid attachment thereto.

4. Registration device (2) according to one of claims 1 to 3, characterized by a navigation camera (30) which is configured to track the optical pattern (22) of the registration body (18) and / or the optical patterns (10) of the bone anchors (4), wherein the navigation camera (30) is preferably arranged to be movable relative to the registration body (18) and / or the bone anchors (4).

5. Registration device (2) according to one of claims 1 to 4, characterized in that the radiopaque markers (20) and the optical pattern (22) of the registration body (18) and / or the optical patterns (10) of the bone trackers (8) are configured for detection in different wavelength ranges.

6. Recording device (2) according to one of claims 1 to 5, characterized in that the radiopaque markers (20) are configured for detection in the X-ray spectrum.

7. Registration device (2) according to one of claims 1 to 6, characterized in that the optical pattern (22) of the registration body (18) and / or the optical patterns (10) of the bone trackers (8) are / are configured for detection in the visible spectrum and / or in the infrared spectrum.

8. Registration device (2) according to one of claims 1 to 7, characterized in that the registration body (18) and / or the bone trackers (8) have a preferably flat outer surface and the respective optical pattern (10, 22) is applied to the outer surface.

9. Registration device (2) according to one of claims 1 to 8, characterized in that a geometric positioning between the x-ray dense markers (20) and the optical pattern (22) of the registration body (18) is unchanging and known.

10. Registration device (2) according to one of claims 1 to 9, characterized in that a geometric positioning between the optical pattern (22) of the registration body (18) and the optical patterns (10) of the bone trackers (8) is unchanging in the fixed state of the temporary fastening device (12).

11. Registration device (2) according to one of claims 1 to 10, characterized in that the temporary fastening device (12) is arranged distal to the registration body (18).

12. Registration device (2) according to one of claims 1 to 11, characterized in that the optical pattern (22) of the registration body (18) is arranged distal to the optical patterns (10) of the bone trackers (8).

13. Registration device (2) according to one of claims 1 to 12, characterized in that an arrangement of the radiopaque markers (22) of the registration body (18) is known such that a pose of the registration body (18) can be determined on the basis of the radiopaque markers (22), and an arrangement of the optical pattern (24) of the registration body (18) is known such that a pose of the registration body (18) can be determined on the basis of the optical pattern (22) of the registration body (24), and an arrangement of the optical pattern (24) of the respective bone anchor (4) is known such that a pose of the respective bone anchor (4) can be determined on the basis of the optical pattern (10) of the respective bone anchor (4).

14. Registration device (2) according to one of claims 1 to 13, characterized in that the bone tracker (8) can be detachably and reproducibly connected or connected to the fastening section (6) in a fixed geometric relationship.

15. Registration device (2) according to one of claims 1 to 14, characterized in that the bone anchor (4) has a rod-shaped base body, at the distal end of which the fastening section (6), in particular in the form of a threaded section or a clamping section, is formed and at the proximal end of which the bone tracker (8) can be connected or is connected.

16. Method for registering at least two bones, with a registration device (2) according to any one of claims 1 to 15, comprising the following steps: Creating a 3D CT scan of the bones (K1, K2, K3), the bone anchors (4) rigidly attached to the bones (K1, K2, K3), and the area connected with one of the Bone anchors (4) rigidly connected to the registration body (18), while the bone anchors (4) are rigidly connected to each other; Segmenting the bones (K1, K2, K3) in the 3D CT scan; Detecting the radiopaque markers (20) of the registration body (18) and determining a pose of the registration body (18) using the radiopaque markers (20); Capturing the optical pattern (24) of the registration body (18) and determining a pose of the registration body (18) based on the optical pattern (24), Capturing the optical patterns (10) of the bone trackers (8) and determining a pose of the respective bone anchor (4) based on the optical pattern (10); Transforming the pose of the registration body (18) determined by the radiopaque markers (20) to the poses of the bone anchors (4) determined by the optical patterns (10) of the bone trackers (8), while the bone anchors (4) are rigidly connected to each other; and Assigning the segmented bones (K1 , K2, K3) to the pose of the respective bone anchor (4) attached to the bone (K1 , K2, K3).

17. Method according to claim 16, wherein the registration body (18) is rigidly connected to one of the bone anchors (4) before the creation of the 3D CT scan and / or is detached from the bone anchor (4) after transformation and mapping.

18. Method according to claim 16 or 17, wherein the bone anchors (4) are rigidly connected to each other before the creation of the 3D CT scan and / or are detached from each other after transformation and mapping.

19. Method according to any one of claims 16 to 18, wherein the acquisition of the optical pattern (24) of the registration body (18) and / or the acquisition of the optical patterns (10) of the bone trackers (8) is carried out from different angles and / or by a moving camera.

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