MEDICAL POSITIONING / ALIGNMENT DEVICE WITH GUIDE TEMPLATE AND OPTICAL MARKING DEVICE

Description

[0001] The present invention relates to a medical device for positioning and / or orienting a medical instrument for endoprosthetic treatment or an implant relative to a patient by directly visualizing / projecting geometric information specific to the instrument or implant and relating to its positioning and / or orientation on or onto the patient. Background of the invention

[0002] In many surgical applications, particularly musculoskeletal applications such as orthopedics, a surgical / medical instrument such as a bone saw, drill, milling cutter, etc., or an implant must be aligned relative to the patient to various structures and / or landmarks such as bone. In this context, the current procedure involves first manually aligning the instrument or implant and subsequently checking the alignment using a mechanical aid, such as extramedullary alignment rods or plates for checking resection thickness. A visual assessment of the situation by the surgeon plays a crucial role, so the quality of the alignment depends, in part, significantly on the surgeon's experience and care.

[0003] A common error in visual-based alignments of instruments / implants relative to the patient / patient bone is to misjudge angles and / or parallels between two objects (instrument versus bone) even when both objects are fully visible, or to create parallax errors due to perspectives or projections perceived in incorrect directions or on enveloped and / or uneven surfaces.

[0004] However, a visual assessment of the alignment of surgical / medical instruments and / or implants relative to the patient / patient bone is also used in situations where some of the structures involved in the alignment are not directly visible to the surgeon, but are located on a bone surface that is obscured by tissue and is not or only partially visible. A common problem in this case is the generation of a parallax error due to incorrect recognition of perspectives or projections, for example, as a result of directional errors.

[0005] The problem described above occurs particularly frequently during TKA (total end arthroplasty) surgeries when aligning cutting guides for proximal tibial incisions or distal femoral incisions. In manual surgery without the use of a navigation system, such cutting guides are positioned and aligned using internal or, in the case of the tibia, external alignment systems. Internal alignment systems are usually referenced relative to the bone marrow and are not visible. For external alignment systems, there are some additional rules of thumb. A gap of two to three finger widths between the alignment system and the patient's bone should ensure good alignment. However, all of the above solutions involve the problem of parallax errors and poor perspective. State of the art

[0006] To date, there is no system on the market that allows the representation and / or representation of alignment axes of surgical instruments or implants, particularly surgical instruments, on the patient, particularly on the patient's skin, bone, or on a patient's bandage, in order to specify and / or verify the positioning of the instruments or implants relative to the patient / patient bone and, in particular, relative to the surgical site with high accuracy. Known systems and solutions generally rely on external mechanical rods or plates for verifying the positioning and alignment of the instruments.

[0007] A further disadvantage is that some information cannot be displayed using conventional technology. In particular, there is no way to visualize an axis or cutting plane directly on the patient's bone. Current instrument systems do not offer reliable control over the precise positioning of the instrument in the surgical field. US 2018 / 0168826 A1 discloses a medical positioning and / or alignment device comprising a guide template for a surgical instrument that can be positioned, aligned, and temporarily fixed to a patient's bone, said guide template comprising a guide section for guiding the surgical instrument according to the position and alignment of the template relative to the patient's bone, and comprising an optical marking device having at least one light source.From FR 2 917 284 A1, US 2010 / 087829 A1 and US 2009 / 234360 A1 a medical positioning and / or alignment device according to the preamble of claim 1 is known.

[0008] Against this background, the object of the present invention is to reduce the aforementioned disadvantages of the prior art, in particular to provide a device with which the user-friendliness can be maximized when positioning surgical instruments, in particular a bone saw or implants, with the greatest possible ergonomics and without any loss of quality.

[0009] This object is achieved by a medical positioning / alignment device according to claim 1 and an optical marking device for such a medical positioning / alignment device according to claim 10.

[0010] The core of the present invention therefore consists in providing a so-called template or guide template, which, for example, must be positioned, aligned, and temporarily fixed to the patient or the corresponding patient bone with respect to a patient's bone, and which has a guide section for guiding a surgical instrument (or implant) according to the position and orientation of the template with respect to the patient's bone. The guide section is preferably adapted to the surgical instrument to be guided and can, for example, be a longitudinal slot in the case of a bone saw and / or a through-hole in the case of a bone drill or milling cutter as a surgical instrument, wherein the corresponding guide section is formed on / in the template.

[0011] Furthermore, the positioning / alignment device according to the invention provides an optical marking device (sighting device) with an (integrated) light source (including power supply), such as a laser or an LED (the latter optionally with an upstream light diaphragm, converging lens and / or prism), which (namely the marking device) is designed and adapted to be temporarily fixed (directly and immediately) on / at the template in a predetermined relative position and relative alignment to the latter and to project instrument-specific geometric information such as a cutting line (in the case of, for example, a bone saw) or a drilling axis (in the case of, for example, a bone drill / milling cutter) onto the patient surface.

[0012] If the (guide) template is to be fixed to the patient / patient bone, the marking device according to the invention must first be fixed to the template in the predetermined relative position and its light source activated. The template can now be aligned, while the light source of the marking device projects instrument-specific information, for example, a cutting line in the case of a template adapted to a bone saw, onto the surface of the patient / patient bone in the surgical area.

[0013] Once the template is correctly positioned, aligned, and secured to the patient's bone, the marking device can be removed.

[0014] Within the scope of the invention, the instrument-specific geometric information may, in particular, be a point and / or a line and / or a plane and / or a three-dimensional representation or hologram.

[0015] In the field of orthopedics, prior to the present invention, there were no solutions for the direct visualization / projection of such geometric information, particularly lines and planes, on-site, i.e., directly on / at the patient during surgery. As already indicated above, a medical-technical instrument within the meaning of the invention is understood to mean, in particular, a medical-technical processing instrument such as a drill, a saw, a milling cutter, a plane, a cutting / welding laser, etc. However, it is also possible to align an implant, particularly an endoprosthesis, with the device according to the invention. Furthermore, the visualized / projected geometric information can include, in particular, geometric information of the patient, such as bone axes or joint axes, start and end points of bones, pivot points of joints, etc.and / or geometric information of the object, such as in particular working directions or axes of a surgical instrument, are also displayed.

[0016] By means of the invention, one or more planes and axes can be visualized / projected simultaneously or staggered in time and directly within the surgical field. This allows a surgeon or operating room operator to display the position and / or orientation of the instruments and the position and / or orientation of the incision in the case of a bone saw, and thus, for example, a bone incision, on the patient / patient bone in a particularly simple and clear manner. Within the scope of the invention, for example, a distal tibia incision can be displayed on the patient / patient bone in relation to the tibia axis. Using the positioning and / or alignment device according to the invention, the surgeon is easily able to perceive the influence of malpositions such as varus or valgus and the inclination alignment on the bone incision in relation to the frontal and sagittal tibia axis. In addition, the femoral frontal axis can also be taken into account.

[0017] The invention allows the projection or visualization of geometric information directly on the patient, particularly on a bony surface. The visualization / projection of real axes and planes by the optical marking device enables surgeons to more accurately determine the position and orientation of the instruments or implants used, thereby avoiding some inaccurate assessments that could lead to suboptimal decisions.

[0018] The idea underlying the invention can be used in almost any operation in which an alignment of a (guiding) template and an instrument / implant guided through it is carried out using hard structures such as bone, for example in operations on the hip, knee and shoulder, in ankle joint prostheses, osteotomies and also in traumatology.

[0019] The idea proposed by the invention goes a step further in the visual control of instrument alignment and positioning by enabling the visualization / projection of axis lines or cutting planes directly on the patient. A particular advantage of the invention is that it can be directly integrated into an Integrated Quality System.

[0020] A key advantage of the invention is the ability to quickly and accurately verify axes, positions, and alignments using direct visualization of patient structures, such as extremities, bones, etc., thereby avoiding the inherent inaccuracies of previously known methods and devices, particularly visual assessment, and the need to mount mechanical rods or control plates. Further advantages include increased accuracy, easier implementation of the surgeon's strategy, time savings, and usability for a wide variety of applications and with different instruments and instrument sets in orthopedics.

[0021] An additional benefit is a reduction in the number of alignment and control instruments required for a specific application. Depending on the application, between two and ten instruments can be saved. Using fewer instruments is associated with a lower risk of infection. In addition to improving quality control, the preparation / use / reprocessing time of the instruments before, during, and after each operation can also be reduced. This translates into savings in operating room time, turnaround time, and / or reprocessing time in the central instrument reprocessing department.

[0022] Considering that currently the only alternatives are purely visual controls without or with the aid of mounted mechanical instruments such as rods and / or control plates, the invention has the advantage of optically displaying / projecting axes and / or resection planes directly onto the patient structures in the surgical field. It is also important to consider that the invention benefits visualization on wrapped and / or uneven surfaces when the use of certain instruments requires mental projection with the risk of parallax error.

[0023] A particular advantage of the invention is that, thanks to the use of the optical marking device (sighting device), the device requires a particularly small amount of space, has few parts susceptible to contamination, and is essentially size-independent in its accuracy. It is therefore particularly accurate, handy, reliable, and cost-effective, both in terms of its use and its reconditioning.

[0024] Advantageous embodiments of the invention are claimed in the subclaims and are explained in more detail below.

[0025] According to the invention, the optical marking device is directly and immediately attached / fixed or attachable / fixable to or on the guide template. In other words, the optical marking device (a portion thereof) is configured / adapted to be brought into engagement / operative engagement with a portion of the guide template. Accordingly, the guide template (a portion thereof) is configured / adapted to be brought into engagement / operative engagement with a portion of the optical marking device. Direct / immediate attachment / fixing thus means, in the present case, in particular that no further components are provided between the optical marking device and the guide template.Thus, when the medical positioning and / or alignment device of the present disclosure is used as intended, a portion of the component "optical marking device" is brought into engagement / operative engagement with a portion of the component "guide template" such that the optical marking device is (temporarily) fixed to / on the guide template.

[0026] One embodiment is characterized in that the optical sighting device has at least one laser. This can be designed, in particular, as a laser scanner. According to a further embodiment, the laser can be designed, in particular, as a line laser. This is understood to mean a laser with special optics with which a line is generated instead of a point when the laser beam hits an object. This can be achieved, for example, by a one-dimensional optical expansion of the laser beam or by a rapid oscillation of the laser beam. By using a laser, a particularly precise display of the position and orientation of the (guide) template and / or of anatomical axes and / or directions relevant for processing can be achieved. In addition, a laser requires only little installation space, so that the device can be designed to be particularly small, which enables a wide range of applications and a high level of flexibility.In this case, the surgical field is not covered by the marking device, but is almost completely visible and accessible to the surgeon.

[0027] A further embodiment of the invention is characterized in that the template is a processing template for guiding a medical processing instrument, in particular a sawing template, a drilling template, or a milling template. Within the scope of the invention, the template can be designed like any known processing template from medical technology, possibly with the difference that it preferably has a coupling structure for position-determined coupling to the optical marking unit. Within the scope of the invention, any medical processing instrument can be aligned and, in particular, guided during processing by means of the template. Examples of such instruments are drills, saws, milling cutters, planes, lasers, etc.

[0028] The coupling structure preferably consists of at least one recess, in particular in the form of a through hole or blind hole with, for example, a round, triangular, square, or polygonal cross-section and / or in the form of a correspondingly shaped projection, in particular a pin. This coupling structure of the template is designed and intended for coupling, engaging, and interacting with a suitably shaped coupling structure of the optical marking device. It is particularly advantageous if the marking unit is detachably coupled to the template on the user side, as this enables particularly convenient and user-friendly processing by first placing the template on the patient with the aid of the marking unit coupled to it in a positionally determined manner, aligning it as intended, and subsequently fixing it in place. The marking device is then decoupled and removed from the (fixed) template for the processing to be carried out.

[0029] As an alternative to the coupling structure described above, it is also possible to use the guide sections already present on the template as a template-side coupling structure for the marking device, which has the advantage that the marking device can always be attached to the template in the correct alignment and positioning with respect to the template.

[0030] For example, in the case of a guide template adapted for bone saws with a sawblade guide slot, the marking device can have a housing with a sword- or fin-like coupling structure that can be pressed into the guide slot of the template according to the tongue and groove principle. If the fin-like coupling structure is also designed so that it narrows from the fin root (close to the device housing) to its free fin edge, it can be inserted into the guide slot of the sawing template in a clamping manner - even with guide slots for different sawblade thicknesses.

[0031] In the case of a drilling template (not shown in detail), the drill hole formed therein can serve as a coupling structure for the marking device, which in this case would be formed, for example, with a thorn-like extension.

[0032] According to one embodiment of the invention, the optical marking unit can emit at least a first laser beam or line laser beam. In particular, it can be coupled to the template in such a way that the first laser beam or line laser beam is directed in a processing direction of the template. In this way, the surgeon can align the template and thus the surgical instrument to be used with it particularly easily, quickly, and precisely in the desired manner, position, and direction.

[0033] According to a further embodiment of the invention, the optical marking unit can emit at least a second laser beam or line laser beam. In particular, it can be coupled to the template in such a way that the second laser beam or line laser beam is directed in an anatomical axis or direction. This facilitates patient-specific orientation for the surgeon.

[0034] The marking device can be designed, in particular, to emit the first and, if applicable, the second laser beam / line laser beam. Preferably, the first laser beam / line laser beam and, if applicable, the second laser beam / line laser beam are non-parallel laser beams and are arranged at an angle to one another, in particular aligned orthogonally to one another.

[0035] In summary, the invention enables the use of line lasers to visualize / project axes, cutting lines, and orientation guides directly on the patient. Materializing / visualizing geometric information directly on, for example, a bony surface or visualizing real axes and planes through an optical system (the marking device) can help surgeons more accurately assess the orientation and alignment of the devices used while avoiding inaccurate assessments that lead to suboptimal decisions.

[0036] Further features and advantages of the present invention will become apparent from the following exemplary and non-limiting description of the invention with reference to the figures. These are merely schematic in nature and serve only to facilitate understanding of the invention. They show: Fig. 1 is a perspective view of an embodiment of a device according to the invention, Fig. 2 is a side view of the embodiment of the Figure 1 , Fig. 3 a perspective view of the embodiment of the Figure 1 from above, Fig. 4 a perspective view of the embodiment of the Figure 1 from below, Fig. 5 a perspective view of a marking unit of the device of Fig. 1 without template, Fig. 6 the marking unit of the Fig. 4 from a lateral view, Fig. 7 the marking unit of the Fig. 4 from above and Fig. 8 the marking unit of the Fig. 4 from diagonally below.

[0037] The Figures 1 to 4each show a complete medical-technical (positioning / alignment) device 1 according to the invention for positioning and / or orienting a surgical instrument or implant (not shown in the figures) relative to a patient / patient bone (also not shown) with direct visualization / projection of instrument / implant-specific geometric information suitable for positioning and / or orienting the instrument / implant on / on the patient / patient bone. Specifically, the Fig. 1 - 4 a sawing template 2 (as is already known per se from the prior art) and a marking device 3 already temporarily fixed thereto as a preferred embodiment of the present invention.

[0038] The device 1 accordingly comprises a (guide) template 2 which interacts with or is suitable for interacting with the bone saw to be positioned and / or oriented, and an optical marking device / unit 3 (also referred to as a sighting device 3) which is coupled to the template 2 in a position-determined manner for visualizing / projecting saw blade-specific geometric information, in the present case, for example, a cutting line.

[0039] The optical sighting device 3 has a line laser (not visible in the figures), which is arranged in a housing 4 of the marking device 3. This is to be understood as a laser preferably with special optics with which a line is generated instead of a point when the laser beam strikes an object (e.g., a patient's bone). In the present example, the optical marking unit 3 emits a first line laser beam 5 and preferably a second line laser beam 6, the propagation planes of which are marked on the housing 4 in the figures. The first line laser beam 5 and the second line laser beam 6 are arranged and aligned non-parallel and at an orthogonal angle to one another.

[0040] The marking device 3 is coupled to the template 2 in such a way that the first line laser beam 5 is directed in the processing direction of the template 2. The second line laser beam 6 is directed in an anatomical axis or direction. This allows a surgeon or operating operator to be shown the position and / or orientation of the instrument used and to be coupled to the template 2, on the one hand, and the position and / or orientation of an incision and thus, for example, a bone incision, particularly easily and clearly directly on / in the patient (bone). For example, a distal tibia incision can be shown in relation to the tibia axis, with the first line laser beam 5 marking and visualizing the incision direction and the second line laser beam 6 marking and visualizing the tibia axis.

[0041] For positionally determined coupling with the template 2, the marking unit 3 according to the invention has a coupling structure, here in the form of a first projection 7 and a second projection 8 spaced therefrom. The template 2 has a recess 9 in the form of a through-opening 9 that matches the projections 7, 8. The marking unit 3 can be easily inserted into the template and, when inserted, is coupled thereto in a positionally determined manner. It can be removed particularly easily by the user by pulling it off the template 2, so that the latter is ready for aligning and guiding an instrument not shown in the figures.

[0042] As can be seen in particular from the Fig. 8As can be seen in concrete terms, the housing 4 of the marking device 3 (on the underside) has a support / mounting bracket or mounting base consisting of a guide rail on which the two-part, in this embodiment sword- or fin-like projection 7, 8 is formed. This means that the two sword- or fin-like projections are arranged parallel to one another in a line. The projections 7, 8 form the coupling structure on the marking device side, which is intended to engage with the coupling structure on the template side.

[0043] Since the (guide) template 2 in the present embodiment is a saw blade template, the template-side coupling structure relates to the saw blade guide slot (generally referred to above as through opening 9), as indicated in the Fig. 1 and 2is shown. The fin-like projections 7, 8 can preferably be triangular or trapezoidal in their respective cross-section, so that they can be pressed into the guide slot 9 (according to the tongue and groove principle) in order to hold / fix the housing 4 of the marking device 3 in the guide slot 9 of the template 2 with frictional engagement.

[0044] As is also clear from the Fig. 1As can be seen, the second laser / laser beam 6 (in this case with a slit-shaped light exit opening) is located directly above the template-side coupling structure and thus on the same level as the guide slot of the saw blade template 2. In other words, the laser beam and the sword- or fin-like projections 7, 8 run essentially parallel (possibly converging but not skewed). When the marking device 3 is fixed on the template 2, a line can be projected onto the patient / patient bone with the aid of the at least one (second) laser / laser beam 6, which line extends virtually in extension to the guide slot 9 of the template 2 and thus optically represents a cutting line of the saw blade.

[0045] As soon as the template 2 is fixed in the correct alignment and position on the patient / patient bone in this way, the marking device 3 can be removed from the template 2 and thus the guide slot or guide groove 9 for the saw blade (not shown) can be released.

[0046] Finally, it should be noted that the marking device 3 according to the invention, in particular, is designed as a one-way product. For this purpose, the housing 4 of the marking device 3, including the coupling structure 7, 8, is made of a plastic (e.g., injection-molded), whereas the light source (including power source) enclosed in the housing is preferably formed by a laser / laser device. This allows the entire device 3 to be manufactured quickly and inexpensively, so that reprocessing is not economically justified. List of reference symbols

[0047] 1Positioning and alignment device 2(Guide) template 3Optical marking device 4Housing of the marking device 5First laser beam / line laser beam 6Second laser beam / line laser beam 7Coupling structure of the marking device, (first) projection 8Coupling structure of the marking device, (second) projection 9Coupling structure of the template, through-hole / guide slot

Claims

1. A medical positioning and / or alignment device comprising a guide template (2) for a surgical instrument which can be positioned, aligned, and temporarily fixed to the patient bone and which has a guide portion (9) for guiding the surgical instrument in accordance with the position and alignment of the template (2) relative to the patient bone, and comprising an optical marking device (3) which has at least one light source (5, 6), and which is designed and adapted, - to be temporarily fixed on / at the guide template (2) in a predetermined relative position and relative orientation thereto, and - to project instrument-specific geometric information in a predetermined relation or positional relationship to the guide portion (9) of the guide template (2) onto the patient surface or patient bone, - characterized in that - the optical marking device (3) can be fastened directly and immediately on / to the guide template (2) so that no further components are provided between the optical marking device (3) and the guide template (2), and - the optical marking device (3) has a housing (4) in which the light source is housed and on which a coupling structure (7, 8) is formed, which can be brought into operative engagement with a coupling structure of the template (2)2. The medical positioning and / or alignment device according to claim 1, characterized in that the guide portion (9) has a longitudinal slot or is a longitudinal slot.

3. The medical positioning and / or alignment device according to claim 1, characterized in that the guide portion (9) has or is a through hole.

4. The medical positioning and / or alignment device according to claim 2, characterized in that the coupling structure on the template side is the longitudinal slot (9) whereas the coupling structure on the side of the marking device (3) is a mounting base with a fin-shaped projection (7, 8) formed thereon which is adapted and provided to be frictionally pressed into the longitudinal slot (9).

5. The medical positioning and / or alignment device according to claim 1, characterized in that the at least one light source (5, 6) comprises a line laser.

6. The medical positioning and / or alignment device according to claim 1, characterized in that the at least one light source (5, 6) is designed as a laser scanner.

7. The medical positioning and / or alignment device according to claim 2, characterized in that the optical marking device (3) emits at least a first laser beam (4) or line laser beam (4) and is coupled to the template (2) in such a way that the first laser beam (4) or line laser beam (4) is directed in a machining direction of the template (4), in particular substantially in the direction of the longitudinal slot (9).

8. The medical positioning and / or alignment device according to claim 7, characterized in that the optical marking device (3) emits at least a second laser beam (6) or line laser beam (6) and is coupled to the template (2) such that the second laser beam (6) or line laser beam (6) is directed in an anatomical axis or direction.

9. The medical positioning and / or alignment device according to claim 8, characterized in that the first laser beam (5) / line laser beam (5) and the second laser beam (6) / line laser beam (6) are arranged at an angle to each other, in particular aligned orthogonally to each other.

10. A marking device for a medical positioning and / or alignment device according to one of the preceding claims 1 to 9, having a housing (4) in which at least one light source, preferably in the form of a laser, is housed and on the outside of which a coupling structure (7, 8) is formed, preferably in one piece of material, characterized in that the coupling structure (7, 8) consists of a mounting base on which a fin-like projection (7, 8) is formed, the free fin edge of which is aligned along the radiation direction of the at least one light source.

11. The marking device according to claim 10, characterized in that the housing (4) including the coupling structure (7, 8) is made of plastic, preferably by injection molding.