A 3D printed limb-extending bone prosthesis system

Abstract

The present invention provides a 3D printed extensible limb bone prosthesis system, which includes a metaphyseal prosthesis, a diaphyseal prosthesis, a buckle, a cone rod, and a patch. The metaphyseal prosthesis includes a first body, and a first fixing plate at the top of the first body is provided with a fixing hole; a conical hole is provided in the first body; the diaphyseal prosthesis includes a second body, and a locking nail hole is provided on the second fixing plate at the top of the second body, and a fixing nail hole is provided on the intramedullary pin at the top of the second body; a plurality of elastic claws are provided on the end surface of the matching column at the bottom of the second body; a uniform hole is provided in the second body; the cone rod includes a conical section and a uniform section; the middle position of the buckle is coaxially provided with a matching hole, an annular limiting protrusion, and a threaded hole from top to bottom, the matching hole is matched with the matching column, and the threaded hole is matched with the thread of the uniform section; the annular limiting protrusion is used to buckle the elastic claw; the patch is arranged between the first body and the buckle, and a through hole is provided in the middle position of the patch. The present invention achieves the extension of the prosthesis better.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to a 3D printed customized extendable limb bone prosthesis system. Background Art

[0002] Traumatic bone defects, osteomyelitis bone defects and bone tumor bone defects are not uncommon in clinical practice and have always been a matter of great concern to trauma orthopedic surgeons. There are many methods for treating large bone defects in the long bones of the limbs, which can be summarized as autologous bone transplantation, external fixator-based bone transport and membrane-induced autologous bone transplantation. These technologies have achieved certain clinical efficacy, but there are also some problems.

[0003] Autologous bone graft is the gold standard for treating bone defects. Autologous bone is easy to obtain, has the ability of osteoinduction, osteoconduction and bone replacement, and has no antigenic reaction. Avascular autologous bone transplantation is obtained by obtaining cancellous bone rich in osteogenic factors and growth factors from the ilium, distal femur, proximal tibia, distal radius and other regions. Although it has osteogenic, osteoconductive and osteoinductive effects, its initial strength is insufficient and is limited to small bone defects (0.5-3cm). There are also complications such as pain, infection, and cutaneous nerve damage in the bone harvesting area. Therefore, most scholars advocate that large bone defects exceeding 5cm require vascularized autologous bone transplantation. These patients often need 6-8 months of bone healing time. This program also has disadvantages such as donor site damage, limited grafts, and insufficient mechanical strength, and it also places high demands on microsurgical techniques.

[0004] The external fixator is one of the major inventions of the last century. Its compression and distraction osteogenesis has become the core concept of bone reconstruction. The daily distraction distance is within 0.75-1.0 mm. This method has solved the treatment of large-area bone defects to a certain extent, but it takes 1-2 months to extend the length by 1 cm during treatment. A 10 cm defect takes at least one year. The treatment cycle is long and the cost is high, which also brings a lot of inconvenience to the patient's life and work. At the same time, there are many problems in the treatment, such as intraoperative neurovascular injury, irritation pain, infection, broken needles, joint contracture, and non-union of the extended end and the opposing end.

[0005] Masquelet technique is also a common method for treating long bone defects. Masquelet technique treatment is divided into two stages. The first stage includes thorough debridement of the injured or infected area, local stable reconstruction, filling of the defect area with antibiotic bone cement, and coverage of soft tissue and local wound healing. This stage is repeated until the infection is completely controlled. After 6-8 weeks, the second stage begins, including the removal of bone cement fillers, replacement of permanent fixation, collection of autologous bone and transplantation to the bone defect area, and closing of the wound. Patients are allowed to partially bear weight after surgery. The patient's bone healing time is slow, and a 6cm defect takes an average of more than 6-8 months to achieve bone healing. This method still has defects such as infection, non-union of the broken ends, insufficient autologous bone material, and donor site complications. In addition, if the defect exceeds 6cm, the chance of inducing poor osteogenesis is very high.

[0006] At the same time, there are currently no relevant products on the market for prostheses that need to be extended in the second stage of surgery. Summary of the invention

[0007] The purpose of the present invention is to provide a 3D printed extendable limb bone prosthesis system to solve the above-mentioned technical problems in the prior art and achieve the extension of the prosthesis.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A 3D printed extensible limb bone prosthesis system, comprising a metaphyseal prosthesis, a diaphyseal prosthesis, a buckle, a cone rod, and a patch, wherein the metaphyseal prosthesis comprises a first body, a first fixing plate arranged at the top of the first body, a screw fixing hole is arranged on the first fixing plate; a first external fixation bracket nail hole is arranged on the first body; a tapered hole penetrating downward is arranged in the first body, and a first microporous structure is arranged in the contact area between the first body and the bone; the diaphyseal prosthesis comprises a second body, a second fixing plate arranged at the top of the second body, and an intramedullary nail, a locking nail hole is arranged on the second fixing plate, and a fixing nail hole opposite to the locking nail hole is arranged on the intramedullary nail; the bottom of the second body has a matching A matching column, wherein a plurality of elastic claws extend from the end face of the matching column; a uniform hole is provided in the second body, which passes downward through the matching column and is opposite to the conical hole; the tapered rod comprises a tapered section for matching with the tapered hole and a uniform section for matching with the uniform hole; the buckle ring is a cylindrical structure, and a matching hole, an annular limiting protrusion, and a threaded hole are coaxially provided in the middle position of the buckle ring from top to bottom, the matching hole matches with the matching column, and the threaded hole matches with the threaded uniform section of the tapered rod; the annular limiting protrusion is used to clamp the elastic claw; the patch block is provided between the first body and the buckle ring, and a through hole for the tapered rod to pass through is provided in the middle position of the patch block.

[0010] Preferably, a second microporous structure is provided on the top of the second body in an area for contacting bones.

[0011] Preferably, the cross section of the tapered rod is waist-shaped; the cross sections of the tapered hole and the uniform hole are both waist-shaped holes.

[0012] Preferably, a rotation hole is provided on the outer circumferential surface of the buckle.

[0013] Preferably, there are multiple rotation holes, and the rotation holes are evenly distributed in the circumference of the buckle.

[0014] Preferably, a guiding inclined surface is provided on the hook of the elastic claw.

[0015] Preferably, the patch block comprises a first arc-shaped block and a second arc-shaped block, and the first arc-shaped block and the second arc-shaped block together form a circular ring structure; the first arc-shaped block and the second arc-shaped block are detachably connected.

[0016] Preferably, both ends of the first arc block are provided with mounting bosses, and both ends of the second arc block are respectively provided with mounting grooves for matching with the mounting bosses; the mounting bosses are provided with mounting holes, and the corresponding positions of the mounting grooves are provided with pin holes opposite to the mounting holes.

[0017] Preferably, the average pore size of the microporous structure is 500-700 μm, and the porosity is 60-80%.

[0018] Preferably, a second external fixing bracket nail hole is provided on the second body.

[0019] The beneficial effects of the present invention are:

[0020] The 3D printed extendable limb bone prosthesis system of the present invention has a microporous structure in the contact area between the prosthesis and the bone tissue, which is beneficial to the stability of the prosthesis. When performing the second-stage extension operation, the conical hole of the metaphyseal prosthesis is first disengaged from the conical section to achieve separation of the metaphyseal prosthesis and the conical rod, and then the prosthesis is periodically extended by traction of an external fixator. When the expected prosthesis height is achieved, the conical rod is moved up by rotating the buckle ring to restore the tight conical fit between the conical rod and the conical hole, and the patch is added to the gap between the metaphyseal prosthesis and the buckle ring and fixed, thereby better achieving the extension of the prosthesis. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the embodiments, and further describe the specific embodiments of the present invention in detail in conjunction with the drawings, wherein

[0022] Figure 1 A schematic diagram of a 3D printed extendable limb bone prosthesis system provided by an embodiment of the present invention;

[0023] Figure 2 A schematic diagram of a metaphyseal prosthesis provided by an embodiment of the present invention;

[0024] Figure 3 A schematic diagram of a diaphyseal prosthesis provided by an embodiment of the present invention;

[0025] Figure 4 A schematic diagram of a buckle provided in an embodiment of the present invention;

[0026] Figure 5 A schematic diagram of a tapered rod provided by an embodiment of the present invention;

[0027] Figure 6 A schematic diagram of a patch provided in an embodiment of the present invention.

[0028] Markings in the accompanying drawings:

[0029] 1. Metaphyseal prosthesis 1-1, first microporous structure 1-2, first fixing plate

[0030] 1-3, screw fixing hole 1-4, tapered hole 1-5, first external fixation bracket nail hole

[0031] 1-6, wedge-shaped opening 2, diaphyseal prosthesis 2-1, second fixing plate 2-2, locking screw hole

[0032] 2-3, intramedullary nail 2-4, fixing nail hole 2-5, second microporous structure 2-6, matching hole

[0033] 2-7, elastic claw 2-8 second external fixing bracket nail hole 3, buckle ring

[0034] 3-1, annular limiting protrusion 3-2, threaded hole 3-3, rotating hole 4, tapered rod

[0035] 4-1, uniform section 4-2, tapered section 5, patch 5-1, first arc block

[0036] 5-2, second arc block 5-3, pin hole DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solution of the present invention, the solution will be further described in detail below in conjunction with specific embodiments.

[0038] like Figures 1 to 6As shown, an embodiment of the present invention provides a 3D printed extendable limb bone prosthesis system, which includes a metaphyseal prosthesis 1, a diaphyseal prosthesis 2, a buckle 3, a tapered rod 4, and a patch 5. The metaphyseal prosthesis includes a first body, a first fixing plate 1-2 arranged on the top of the first body, and a screw fixing hole 1-3 is arranged on the first fixing plate; a first external fixation bracket nail hole 1-5 is arranged on the first body; a tapered hole 1-4 penetrating downward is arranged in the first body, the diameter of the upper end of the tapered hole is smaller than the diameter of the lower end of the tapered hole, and a first microporous structure 1-1 is arranged in the contact area between the first body and the bone; the diaphyseal prosthesis includes a second body, a second fixing plate 2-1 arranged on the top of the second body, and an intramedullary nail 2-3, the second fixing plate is provided with a locking nail hole 2-2, and the intramedullary nail is provided with a screw hole opposite to the locking nail hole. A fixing nail hole 2-4; the bottom of the second body has a matching column, and the end face of the matching column extends with a plurality of elastic claws 2-7; a uniform hole 2-6 is provided in the second body, which passes through the matching column downward and is opposite to the conical hole; the cone rod 4 includes a conical section 4-2 for matching with the cone hole, and a uniform section 4-1 for matching with the uniform hole; the buckle 3 is a cylindrical structure, and the middle position of the buckle is coaxially provided with a matching hole, an annular limiting protrusion 3-1, and a threaded hole 3-2 from top to bottom, the matching hole matches with the matching column, and the threaded hole matches with the uniform section thread of the cone rod; the annular limiting protrusion 3-1 is used to snap on the elastic claw to achieve limiting; the patch block 5 is arranged between the first body and the buckle ring, and the middle position of the patch block 5 is provided with a through hole for the cone rod to pass through.

[0039] The 3D printed extendable limb bone prosthesis system provided by the embodiment of the present invention, when performing a second-stage lengthening operation, first separates the metaphyseal prosthesis 1 from the tapered hole and the tapered section of the metaphyseal prosthesis 1, and then achieves periodic prosthesis lengthening through traction of an external fixator. When the expected prosthesis height is achieved, the tapered rod 4 is moved upward by rotating the buckle 3, and the tight tapered fit between the tapered rod 4 and the tapered hole is restored. The patch is added to the gap between the metaphyseal prosthesis and the buckle and fixed, thereby better achieving the lengthening of the prosthesis.

[0040] Furthermore, the second microporous structure 2-5 is provided at the top of the second body in the area in contact with the bone. It can be understood that the first microporous structure 1-1 and the second microporous structure 2-5 are both areas in contact with the bone, which is conducive to bone ingrowth, so as to achieve long-term stability of the prosthesis system after implantation in the human body; the metaphyseal bone prosthesis 1 and the diaphyseal prosthesis 2 can be made of titanium alloy material through additive manufacturing process.

[0041] like Figure 5As shown, the cross section of the tapered rod 4 is waist-shaped; the cross sections of the tapered hole and the uniform hole are both waist-shaped holes, thereby effectively preventing the metaphyseal prosthesis and the diaphyseal prosthesis from rotating.

[0042] Furthermore, a rotation hole 3 - 3 is provided on the outer circumferential surface of the buckle 3 , so that the buckle 3 can be easily rotated through the rotation hole.

[0043] Preferably, there are multiple rotation holes 3 - 3 , and each of the rotation holes is evenly distributed in the circumferential direction of the buckle.

[0044] Specifically, a guiding slope is provided on the hook of the elastic claw 2-7, so that when the elastic claw penetrates into the buckle and contacts the annular limiting protrusion 3-1, it can smoothly pass over the annular limiting protrusion, so that the hook is hung on the annular limiting protrusion 3-1, thereby conveniently realizing the connection between the diaphyseal prosthesis 2 and the buckle 3, and at the same time ensuring that the buckle can achieve resistance-free rotation without affecting the rotation of the buckle.

[0045] Furthermore, the patch block 5 includes a first arc block 5-1 and a second arc block 5-2, and the first arc block and the second arc block together form a circular ring structure; the first arc block and the second arc block are detachably connected.

[0046] like Figure 6 As shown, both ends of the first arc block 5-1 are provided with mounting bosses, and both ends of the second arc block 5-1 are provided with mounting grooves for matching with the mounting bosses; the mounting bosses are provided with mounting holes, and the corresponding positions of the mounting grooves are provided with pin holes 5-3 opposite to the mounting holes. With this solution, the first arc block and the second arc block can be connected by using a pin to pass through the pin hole and match with the mounting hole.

[0047] Preferably, both the first arc-shaped block and the second arc-shaped block are semicircular blocks.

[0048] The average pore size of the microporous structure is 500-700 μm, and the porosity is 60-80%.

[0049] Furthermore, the second body is provided with a second external fixation bracket nail hole, so as to facilitate the use of external fixation bracket traction in the second stage operation to achieve regular extension. The bottom of the first body is provided with a wedge-shaped opening 1-6.

[0050] The 3D printing extensible limb bone prosthesis system provided by the embodiment of the present invention has a prosthesis geometric morphology design based on the bone defect area and the healthy side limb bone geometry, so the prosthesis can restore the morphology of the bone defect area and can achieve large-segment bone defect filling. At the same time, the prosthesis and the bone contact area are designed with a microporous structure, which is conducive to the growth of bone tissue and the stability of the prosthesis. In practical applications, the combination of metaphyseal prosthesis-diaphyseal prosthesis, diaphyseal prosthesis-diaphyseal prosthesis, and metaphyseal prosthesis-diaphyseal prosthesis can be selected according to the bone defect site. One of the prostheses needs to be connected by a cone rod to achieve a tight fit. The cone rod connection achieves stable fixation, and it is also convenient for the second-stage extension surgery to achieve the separation of the cone fit, and it is convenient to cooperate with the use of an external fixator traction in the second-stage surgery to achieve regular extension. During the second-stage extension surgery, the extension height can be determined according to the patient data, and a patch 5 of the corresponding height can be designed. By adjusting the prosthesis, the corresponding gap height is adjusted, and the patch 5 is added to the gap and fixed, thereby achieving the extension of the prosthesis. The buckle 3 is connected to the uniform section of the cone rod by a thread, so that the cone rod can be controlled to move freely up and down in the internal space of the prosthesis. The geometric shape of the extendable limb bone prosthesis system can be customized according to the patient's data, and the product can be realized by combining additive manufacturing.

[0051] The above are only preferred embodiments of the present invention. It should be pointed out that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Moreover, after reading the contents of the present invention, relevant technical personnel in the field may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A 3D printed extremity bone prosthesis system capable of extension, characterized in that: It includes a metaphyseal prosthesis, a diaphyseal prosthesis, a buckle, a cone rod, and a patch. The metaphyseal prosthesis includes a first body, a first fixing plate arranged on the top of the first body, and a screw fixing hole is arranged on the first fixing plate; a first external fixation bracket nail hole is arranged on the first body; a tapered hole penetrating downward is arranged in the first body, and a first microporous structure is arranged in the contact area between the first body and the bone; the diaphyseal prosthesis includes a second body, a second fixing plate arranged on the top of the second body, and an intramedullary nail, a locking nail hole is arranged on the second fixing plate, and a fixing nail hole opposite to the locking nail hole is arranged on the intramedullary nail; the bottom of the second body has a matching column, and the matching column A plurality of elastic claws extend from the end face; a uniform hole is provided in the second body, which passes downward through the matching column and is opposite to the conical hole; the tapered rod includes a tapered section for matching with the tapered hole and a uniform section for matching with the uniform hole; the buckle ring is a cylindrical structure, and a matching hole, an annular limiting protrusion and a threaded hole are coaxially provided in the middle position of the buckle ring from top to bottom, the matching hole matches with the matching column, and the threaded hole matches with the threaded uniform section of the tapered rod; the annular limiting protrusion is used to clamp the elastic claw; the patch block is provided between the first body and the buckle ring, and a through hole for the tapered rod to pass through is provided in the middle position of the patch block.

2. The 3D printed extendable limb bone prosthesis system according to claim 1, characterized in that: A second microporous structure is disposed on the top of the second body in an area for contacting bones.

3. The 3D printed extendable limb bone prosthesis system according to claim 1, characterized in that: The cross section of the tapered rod is waist-shaped, and the cross sections of the tapered hole and the uniform hole are both waist-shaped holes.

4. The 3D printed extendable limb bone prosthesis system according to claim 1, characterized in that: A rotation hole is arranged on the outer circumferential surface of the buckle ring.

5. The 3D printed extendable limb bone prosthesis system according to claim 4, characterized in that: There are multiple rotation holes, and the rotation holes are evenly distributed in the circumference of the buckle.

6. The 3D printed extendable limb bone prosthesis system according to claim 1, characterized in that: A guiding inclined surface is arranged on the hook of the elastic claw.

7. The 3D printed extendable limb bone prosthesis system according to claim 1, characterized in that: The patch block includes a first arc block and a second arc block, and the first arc block and the second arc block together form a circular ring structure; the first arc block and the second arc block are detachably connected.

8. The 3D printed extendable limb bone prosthesis system according to claim 7, characterized in that: Both ends of the first arc block are provided with mounting bosses, and both ends of the second arc block are respectively provided with mounting grooves for matching with the mounting bosses; the mounting bosses are provided with mounting holes, and the corresponding positions of the mounting grooves are provided with pin holes opposite to the mounting holes.

9. The 3D printed extendable limb bone prosthesis system according to claim 1, characterized in that: The average pore size of the microporous structure is 500-700 μm, and the porosity is 60-80%.

10. The 3D printed extendable limb bone prosthesis system according to any one of claims 1 to 9, characterized in that: The second body is provided with a second external fixing bracket nail hole.

Images