Pectus excavatum correction plate system

Abstract

A pectus excavatum correction plate system includes at least one correction plate having an elongated shape and a row of holes, and a stabilizing plate adapted to be attached to the side of a patient's chest. The stabilizing plate and the correction plate are adapted to be bolted together through the holes. The holes in the correction plate are internally threaded. The system further includes a headless double-threaded locating screw with a socket and a first thread complementary to the thread of the hole in the correction plate. The locating screw also has a second thread passing through the hole in the stabilizing plate. The system also includes a nut with an internal thread complementary to the second thread of the locating screw. The nut has a head wider than the hole in the stabilizing plate. The correction plate has teeth around the holes, while the stabilizing plate has teeth on at least a partial circumference around the holes that are complementary to the teeth of the correction plate.

Description

Technical Field

[0001] This invention relates to a system for treating chest deformities. Prior Technology

[0002] Note that the pectus excavatum correction plate system (or sternal rib plate system) is used to treat chest deformities, also known as pectus excavatum, using Dr. Nuss's Minimally Invasive Pectus Excavatum Repair (MIRPE) technique, which involves inserting a correction plate under the sternum to correct the deformity. Pectus excavatum correction plate systems are commercially available. They are supplied by ChM sp. z oo with Instruments Group 40.5841.000. Instructions for this surgical technique were released by the manufacturer in 2012 under the number ST / 42A.

[0003] During the procedure, the patient lies supine with arms abducted at the shoulders. Mark the lowest point of the pectus excavatum using a sterile marking pen, or, if the point is below the sternum, mark the lowest point of the sternum. On both sides of the chest, mark the intercostal spaces aligned with or closest to the marked point on the sternum. On the extension of the marked line, between the anterior and mid-axillary lines, make a transverse incision to insert the corrective plate. The length of the corrective plate should be determined by appropriate measurements beforehand. The shape and length of the plate depend on the shape of the deformity. Proper shaping of the plate is accomplished by bending it using the bending tools provided in the instrumentation kit.

[0004] During the insertion of the pectus excavatum correction plate system as an implant, sharp curvatures, excessive bending, and bending of the implant at the location of the incision must be avoided. There is a risk of implant displacement or rotation. This could potentially damage tissues or organs located near the plate. Special care should be taken during the implantation procedure to avoid contact between the implant or device and the heart and lungs. Therefore, a stabilizing plate is used during the procedure. The stabilizing plate is mounted at the end of the correction plate of the pectus excavatum correction plate system and attached to the chest muscles. The stabilizing plate has recesses for receiving the correction plate, preventing rotation of the correction plate relative to the stabilizing plate, and holes for connecting the correction plate and the stabilizing plate via bolts.

[0005] Korean Patent KR20130045009A discloses a pectus excavatum correction plate system, which includes a correction plate that is connected to a stabilizing plate by screws that pass through holes in the correction plate and are screwed into the correction plate.

[0006] US Patent US2011251540A1 discloses an apparatus and method for treating pectus excavatum. The apparatus includes a rod stabilizer assembly having two or more channels for securing and holding corrective plates (pectus excavatum rods) within the patient's pleural cavity. The corrective plates are attached to the stabilizer plate by placing them in a pleural socket and locking them with screws that pass through one of the holes provided in the corrective plate and are screwed into the stabilizer plate. This method involves complex surgical techniques because it requires positioning the end of the corrective plate within the channels of the stabilizer plate during surgery, as well as adjusting the positions of the two holes and the screw.

[0007] European Patent EP3579772B1 discloses a pectus excavatum correction plate system, comprising a correction plate and a stabilizing plate. The stabilizing plate has a channel shaped to fit the correction plate and is adapted to receive the correction plate and allow its movement. A mechanism is provided in this channel to prevent movement of the correction plate by rotating a provided cam key. Summary of the Invention

[0008] The main objective of this invention is to simplify surgical techniques, shorten the time required to insert the corrective plate into the chest cavity, and reduce the risks to the patient.

[0009] Another objective of this invention is to simplify the complex manufacturing process and increase the acceptable tolerances when installing components required for safe installation.

[0010] To achieve the above objectives, the technical means employed in this invention include: at least one corrective plate having an elongated shape, having several narrowed end portions and several rows of holes; at least one stabilizing plate having several rows of holes, the plate being adapted to be attached to the side of a patient's chest; wherein the stabilizing plate and the corrective plate are connected to each other by threads in the aforementioned holes, the holes in the corrective plate having internal threads, and the system further includes: a headless double-threaded positioning screw having a socket for tool use and having a first thread complementary to the threads in the holes in the corrective plate; wherein the positioning screw also has a second thread (loosely) passing through the holes in the stabilizing plate; and a nut having an internal thread complementary to the second thread of the positioning screw, the nut having a head wider than the hole in the stabilizing plate; wherein the corrective plate has teeth around the holes, and the stabilizing plate has teeth on at least a portion of its circumference around the holes that are complementary to the teeth of the corrective plate. This provides a stable connection between the plates during a simple and predictable surgical implantation process. This process requires only two components of the system at each step, instead of three or more.

[0011] Based on the aforementioned features, in one feasible embodiment, there are at least two stabilizing plates.

[0012] Based on the aforementioned features, in one feasible embodiment, the tooth pattern of the hole in the corrective plate is concave, and the tooth pattern of the hole in the stabilizing plate is convex.

[0013] Based on the aforementioned features, in one feasible embodiment, the threads of the hole in the stabilizing plate only cover a portion of the hole's circumference that is substantially parallel to the length of the stabilizing plate, wherein the nut has a shank that is at least partially accommodated in the hole of the stabilizing plate. This configuration provides a sufficiently long threaded portion without unduly increasing the height of the connection.

[0014] Based on the aforementioned features, in one feasible embodiment, the positioning screw has a flange located between the first thread and the second thread, the diameter of which is larger than the minimum diameter of the hole in the straightening plate. This solution allows the screw to be locked at the correct depth.

[0015] Based on the aforementioned features, in one feasible embodiment, the diameter of the flange is smaller than the hole in the stabilizing plate. This allows the nut shank to contact the straightening plate, thereby providing better stability.

[0016] Based on the aforementioned features, in one feasible embodiment, the flange is tapered, and the hole in the corrective plate has a complementary tapered shape at its upper portion, which ensures better fixation.

[0017] Based on the aforementioned features, in one feasible embodiment, the positioning screw has an unthreaded portion at the end opposite the socket, which makes it easier to insert it into the hole.

[0018] Complementary teeth in the holes of the corrective and stabilizing plates prevent the plates from rotating relative to each other at relatively low nut tightening torque. Furthermore, these components can rotate relative to each other without breaking the connection after the nut is installed and before tightening, which facilitates the installation of the stabilizing plate. Using toothed surfaces to prevent plate rotation, instead of channels in stabilizing plates known in the prior art, simplifies the process of connecting the corrective and stabilizing plates and avoids the need to fit the stabilizing plate over the end of the corrective plate, which can be cumbersome if the corrective plate needs to be bent. The system according to the invention allows for the connection of two (instead of three) components at a time during surgery, with the connection of all three components achieved gradually. This avoids the hassle of simultaneously aligning two holes and one screw. After bending the corrective plate, it is easy to select the correct hole to screw into the positioning screw and to check for deformation of the hole due to bending before surgery by screwing in the positioning screw. This reduces the risk of patient exposure. The system allows subsequent components to be applied from the outside without needing to be approached from below (i.e., from inside the patient), reducing the invasiveness of the procedure. Simple Explanation of the Diagram

[0019] Figure 1 is a schematic diagram of the pectus excavatum correction plate system installed on a patient. Figure 2 is a schematic diagram of a method for connecting a straightening plate to a stabilizing plate using positioning screws and nuts in an embodiment of the present invention. Figure 3 shows a top view of a preferred embodiment of the present invention, i.e., viewed from the back of the patient's body after installation. Figure 4 shows a preferred embodiment of the present invention in a bottom view, that is, viewed from the bottom side of the patient's body after installation. Figure 5 is an enlarged perspective view of the end portion of the correction plate according to a preferred embodiment of the present invention, showing the tooth pattern around the hole. Figure 6 is a side view of the structure of the correction plate according to a preferred embodiment of the present invention, highlighting the cross-section of the hole. Figure 7 is a bottom view of the stabilizing plate according to a preferred embodiment of the present invention, that is, viewed from the bottom of the patient's body after installation. Figure 8 is a top view of the stabilizing plate according to a preferred embodiment of the present invention, i.e., viewed from the back of the mounting towards the bottom of the patient's body. Figure 9 is an enlarged perspective view of a stabilizing plate according to a preferred embodiment of the present invention, showing the last two holes at the end of the plate. Figure 10 is an enlarged side view of a stabilizing plate according to a preferred embodiment of the present invention, showing the last two holes at the end of the plate and highlighting the cross-section of the holes. Figure 11 is a schematic diagram of a positioning screw according to a preferred embodiment of the present invention. Figure 12 is a schematic diagram of a positioning screw according to a preferred embodiment of the present invention. Figure 13 is a schematic diagram of a nut according to a preferred embodiment of the present invention. Figure 14 is a schematic diagram of a nut according to a preferred embodiment of the present invention. Implementation

[0020] The pectus excavatum correction system is used by inserting at least one correction plate 10 under the patient's sternum and stabilizing it with at least one, but preferably two, stabilizing plates 30. The stabilizing plates 30 may be attached to the patient's ribs or muscles to secure the correction plate 10 inserted under the sternum and ensure its stable position. The stabilizing plates 30 prevent rotation of the correction plate 10. Sometimes one stabilizing plate 30 is used, in other cases two. In some cases, using two correction plates 10 is also reasonable. The system according to the invention provides possibilities for different applications.

[0021] Referring to Figure 1, this is a schematic diagram of the pectus excavatum correction plate system of this invention and the patient's skeleton. In this embodiment, the system includes two stabilizing plates 30 and two correcting plates 10, forming a stable frame. Due to the solution according to the invention, the possibility of the attachment system "tilting" is limited because the connection between the stabilizing plates 30 and the correcting plates 10 is fixed to prevent rotation. Therefore, it is not necessary to attach the stabilizing plates to the patient's ribs or muscles.

[0022] In the system according to an embodiment of the present invention, the stable connection between the correction plate 10 and the stabilizing plate 30 is performed as shown in FIG2.

[0023] Use a screwdriver with a tip that fits the screw socket 29 to screw the screw 20 into the threaded hole 15 of the straightening plate 10.

[0024] When the patient is supine, the top side 10A of the orthotic plate 10 faces upwards, away from the patient's body, while its bottom side 10B faces downwards, towards the patient's body. Because the hole 15 is threaded, the positioning screw 20 does not need to be screwed in from below; it can be screwed in from above. This minimizes the need to move the orthotic plate 10 within the patient's body. The screwing-in process only requires aligning two components: the positioning screw 20 and the orthotic plate 10.

[0025] A typical problem associated with existing orthotic plates is deformation of the holes in the plate during use. This risk also exists in the system of the present invention; however, before surgery, the orthotic plate can be easily tried on on the patient, and the alignment of the positioning screws 20 and the target holes 15 can be checked. Therefore, screwing problems can be detected before the actual surgery begins, and if a problem does occur, a new orthotic plate can be bent and the damaged plate discarded. In this way, the surgical risks associated with aligning system components during surgery can be avoided.

[0026] The hole 35 in the stabilizing plate 30 fits onto the positioning screw 20 that screws into the orthotic plate. This can be done quickly because the hole 35 is unthreaded. The bottom side 30A of the stabilizing plate 30 is oriented downwards; in other words, the bottom side 30A faces the patient's body and the orthotic plate 10, while the top side 10A of the orthotic plate 10 is oriented upwards. After the hole 35 in the stabilizing plate 30 fits onto the positioning screw 20, the nut 40 is screwed onto the positioning screw 20 behind the stabilizing plate 30. Before the nut 40 is tightened, the stabilizing plate 30 can rotate relative to the orthotic plate 10, but they remain connected and the system will not come apart. Thus, the stabilizing plate is easy to attach. Slightly tightening the nut creates slight rotational resistance, thereby eliminating accidental displacement. After attaching the stabilizing plate 30, tighten the nut 40. Because of the complementary teeth 16 and 36 of holes 15 and 35, the plates are locked together with a relatively low tightening torque, which eliminates the so-called risk of cold welding and makes it easier and safer to remove the pectus excavatum correction plate system to remove the correction plate 10 at the end of treatment.

[0027] Referring to the corrective plate 10 of an embodiment of the present invention shown in Figures 3-6. The corrective plate 10 is made in a variant having a length of 180 ÷ 405 mm and a thickness of 2.8 mm. In the central portion 11, the width of the corrective plate 10 is 14 mm. In the end portion 12, the corrective plate 10 narrows to a width of 12 mm. At the end of the corrective plate 10, a hole 17 with a diameter of 3 mm is provided to facilitate insertion of the corrective plate 10 under the sternum. These holes also make it easier to grip the corrective plate using auxiliary hooks during attachment of the stabilizing plate 30. Those skilled in the art can choose other plate lengths and thicknesses or hole diameters as needed. However, the above combination has proven to be both convenient and compatible with patient size and available instruments.

[0028] In this embodiment, the straightening plate 10 is made of a titanium alloy that provides appropriate flexibility. Ti6Al4V is particularly suitable. Alternatively, the plate can also be made of pure titanium, which is more ductile and easier to bend.

[0029] On the top side 10A, facing away from the patient, the edge of the corrective plate 10 is more sloping than that on the bottom side 10B (facing the patient). The sloping upper edge of the top side 10A ensures compatibility with known and available stabilizing plates in the prior art, which are designed to fit over the corrective plate. This makes the use of hospital storage space more efficient, and the presence of an easy-to-use bolted connection at least at one end significantly simplifies the procedure.

[0030] In this embodiment, each end portion 12 of the corrective plate 10 has a row of four holes 15 for connection to the stabilizing plate 30. Experiments have shown that four holes are generally sufficient for patients with a wide range of chest sizes. The pectus excavatum corrective plate system is used to treat pectus excavatum in patients aged 12-16 years.

[0031] In this embodiment, a hole 15 with a diameter of 4.7 mm (the maximum diameter of the cone) and an internal metric double thread of 4.5 mm is used. This hole 15 has a threaded cylindrical central portion and a tapered portion that widens towards the top side 10A, i.e., away from the patient. In this tapered portion, the flange 22 of the positioning screw 20 is partially received and locked after the screw is screwed in. This design advantageously reduces the risk of accidental loosening and achieves a more stable screw lock. Furthermore, the tapered widened hole makes screw insertion easier during surgery, thereby reducing the risk of the operator dropping the screw and statistically reducing the surgery time.

[0032] On the top side 10A of the corrective plate 10, a toothed pattern 16 is provided around the hole 15 along its entire circumference. In this embodiment, the toothed pattern 16 is provided along the entire circumference and is concave, that is, the tooth is a recess in the top side 10A of the corrective plate 10. These recesses are complementary to the convex toothed pattern of the stabilizing plate 30. Other types of complementary toothed patterns can be used. However, it should be noted that using concave toothed patterns can prevent situations that may arise when inserting the corrective plate under the sternum, whereas convex toothed patterns may cause such situations.

[0033] In this embodiment, a toothed pattern consisting of 50 teeth with a depth of 0.2 mm is used, which has proven to be easy to manufacture and strike a good balance between efficiency and comfort in use. Effective connection and convenient surgical insertion are achieved through toothed patterns with 18 to 100 teeth and a depth of 0.1 mm to 0.5 mm.

[0034] Referring to Figures 7-10, a stabilizing plate 30 according to an embodiment of the present invention is shown. In this embodiment, the stabilizing plate 30 has an elongated shape and includes 17 holes 35. Due to the beveled edges, the stabilizing plate 30 is wider at the locations of the holes 35, as shown in Figures 7, 8, and 9. The wavy bevels soften the edges and reduce irritation to the tissue surrounding the implant. The reduced bevels at the hole locations increase strength.

[0035] The stabilizing plate 30 is manufactured in a variant with a length of 42 ÷ 186 mm, a thickness of 1.5 mm, and a width of 10 mm. The hole 35 has a diameter of 4.8 mm, and the countersunk hole diameter is 6.5 mm. A thickness of 1.5 mm has proven to be optimal, but good results have also been obtained in a wider range, from 1 to 2 mm.

[0036] In this embodiment, the stabilizing plate 30 is made of pure titanium. The plate can also be made of titanium alloy, but pure titanium is more ductile and easier to bend.

[0037] In the stabilizing plate 30, on the bottom side 30A facing the patient and the corrective plate 10, a portion of the circumference around the hole 35 is provided with raised teeth 36, protruding above the bottom side 30A. The teeth 36 are only provided on a portion of the circumference of the hole 35 extending along the long outer edge of the stabilizing plate. This toothing has proven sufficient and easier to produce than raised teeth on the entire circumference; furthermore, the toothing only on a portion of the circumference reduces tissue irritation when the stabilizing plate is inserted subcutaneously.

[0038] Referring to Figures 11 and 12, a positioning screw 20 according to an embodiment of the invention is shown. The screw has a first thread 21 complementary to the thread of the hole 15 in the straightening plate 10 and a second thread 23 complementary to the thread 43 in the nut 40 and freely passing through the hole 35 in the stabilizing plate 30. These threads are advantageously separated by a tapered flange 22. This screw flange matches the upper part of the hole 15 in the straightening plate 10, improving the fixation of the positioning screw 20. The positioning screw 20 has no head, so there is not much clearance when it passes through the hole 35, but its upper part has a socket 29 for use with a fastening tool, preferably a box wrench. In the lower part, the screw 20 advantageously has a threadless portion 28, which makes it easier to place the positioning screw 20 straight in the hole 15, relative to the axial direction of the internal thread. Due to this threadless portion 28, the positioning screw 20 has a more pronounced asymmetry, and the operator can assess its orientation more quickly. The portion 24 visible in Figure 11 is the technical undercut of the thread 23.

[0039] In an embodiment of the invention, the positioning screw 20 is made of titanium alloy and has a diameter of 4.7 mm (the maximum diameter of the cone). The first thread has a diameter of 4.5 mm, a length of 2 mm, and a pitch of 1 mm. The second thread has a diameter of 4.5 mm, a length of 3.5 mm, and a pitch of 1 mm. In this embodiment, both threads are identical and are double-threaded. This is technically simple, but different threads could also be used. The second thread 23 is incompatible with the thread of the hole 15, further preventing errors during the procedure.

[0040] Referring to the nut 40 in Figures 13 and 14, the nut 40 has an internal thread 43 complementary to the second thread 23 of the positioning screw 20 and a head 42 suitable for tightening tool tips, particularly torque wrenches. The nut 40 is provided with a shank 41 that is at least partially received in a hole 35 in the stabilizing plate 30. This stabilizes the connection between the corrective plate 10 and the stabilizing plate 30, and the overall height of the connection is also reduced, thus reducing irritation to the tissues surrounding the implant, as the nut portion is recessed into the hole in the plate while maintaining the necessary thread height.

[0041] In conclusion, the technical means disclosed in this invention do indeed possess the requirements for invention patents, namely "novelty," "progressiveness," and "industrial applicability." I humbly request that Your Excellency grant me a patent to encourage invention. I am deeply grateful for your kindness.

[0042] However, the above-disclosed drawings and descriptions are merely preferred embodiments of the present invention. Modifications or equivalent changes made by those skilled in the art within the spirit and scope of this application should still be included within the scope of the patent application.

[0043] 10: Correction board 10A: Top side of the correction board 10B: Bottom side of the correction board 11: Central Part 12: End portion 15: Kong 16: Tooth pattern 17: Kong 20: Positioning screws 21: First thread 22: Flange 23: Second thread 24: Technical Breakthrough 28: Unthreaded section 29: Chengwo 30: Stabilizing plate 30A: Bottom side of the stabilizing plate 35: Kong 36: Tooth pattern 40: Nuts 41: Handle 42: Head 43: Internal thread

Claims

1. A pectus excavatum correction plate system, comprising: at least one correction plate (10) having an elongated shape, having a plurality of narrowed end portions (12) and having a plurality of rows of holes (15); at least one stabilizing plate (30) having a plurality of rows of holes (35), the stabilizing plate (30) being adapted to be attached to the side of a patient's chest; wherein the stabilizing plate (30) and the correction plate (10) are connected to each other by threads of the aforementioned holes (15, 35); characterized in that: the holes (15) of the correction plate (10) are provided with internal threads, and the system further comprising: a headless double-threaded positioning screw (20) having a socket (29) for tooling and having a first thread (21) complementary to the threads of the holes (15) in the correction plate (10); The positioning screw (20) is provided with a second thread (23) passing through the hole (35) in the stabilizing plate (30); and a nut (40) is provided with an internal thread (43) complementary to the second thread (23) of the positioning screw (20), the nut (40) having a head (42) wider than the hole (35) in the stabilizing plate (30); wherein the straightening plate (10) is provided with teeth (16) around the hole (15), and the stabilizing plate (30) is provided with a tooth (36) on at least a portion of the circumference around the hole (35) complementary to the tooth (16) of the straightening plate (10).

2. The pectus excavatum correction plate system as described in claim 1, wherein, It has at least two stabilizing plates (30).

3. The pectus excavatum correction plate system as described in claim 1, wherein, The tooth pattern (16) of the hole (15) in the correction plate (10) is concave, and the tooth pattern (36) of the hole (35) in the stabilizing plate (30) is convex.

4. The pectus excavatum correction plate system as described in claim 3, wherein, The teeth (36) of the hole (35) in the stabilizing plate (30) only cover the portion of the circumference of the hole (35) that is arranged substantially parallel to the length of the stabilizing plate (30).

5. The pectus excavatum correction plate system as described in any one of claims 1 to 4 of the patent application, wherein, The nut (40) has a handle (41) that can be at least partially accommodated in the hole (35) of the stabilizing plate (30).

6. The funnel chest correction plate system as described in claim 5, wherein the positioning screw (20) is provided with a flange (22) located between the first thread (21) and the second thread (23), the diameter of which is greater than the minimum diameter of the hole (15) in the correction plate (10).

7. The pectus excavatum correction plate system as described in claim 6, wherein, The diameter of the flange (22) is smaller than that of the hole (35) in the stabilizing plate (30).

8. The pectus excavatum correction plate system as described in claim 7, wherein, The flange (22) is tapered, and the hole (15) in the correction plate (10) has a complementary tapered shape on its upper part.

9. The pectus excavatum correction plate system as described in claim 8, wherein the positioning screw (20) has an unthreaded portion (28) at the end opposite to the socket (29).

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