Unicondylar joint thighbone 3D printing guide plate

Abstract

The utility model relates to the technical field of medical instruments, and discloses a unicondylar joint thighbone 3D printing guide plate which comprises a guide plate body, a thighbone far-end prosthesis far-end locking hole is formed in one side of the guide plate body, a thighbone far-end prosthesis near-end locking hole and a guide plate fixing hole are formed in one side of the guide plate body, and the outer side of the guide plate is clamped and pressed. The knee joint CT scanning 3D guide plate is reasonable in structure, knee joint CT scanning is performed before an operation, the 3D guide plate is designed, and template clamping and pressing are performed by clamping and pressing the outer side of the guide plate, clamping and pressing the inner side of the guide plate and clamping and pressing the thighbone posterior condyle during use. After a butt joint template is prepared to be clamped and pressed before an operation, a kirschner wire is driven into a guide plate fixing hole to fix and reinforce the stability of the guide plate body, the guide plate body is prevented from loosening in the osteotomy process, a bent pry is used for protecting inner side collateral ligaments on the outer side in the thighbone posterior condyle osteotomy groove thighbone posterior condyle cutting operation, and the inner side is of a closed structure to protect anterior and posterior cruciate ligaments. By means of the design, the swing saw can effectively move in the osteotomy process, and ligaments and surrounding tissue can be prevented from being damaged.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically a 3D-printed guide plate for the femur of a unicompartmental joint. Background Technology

[0002] Knee osteoarthritis is a common joint disease characterized by cartilage degeneration and secondary osteophyte formation. It is one of the leading causes of non-traumatic disability. The location and number of compartments in knee osteoarthritis lesions correspond to different treatment approaches. Multi-compartment lesions are primarily treated with total knee replacement. For treating late-stage unilateral compartmental lesions in knee osteoarthritis, unicompartmental knee replacement has been clinically proven to be a highly effective treatment method. Compared to total knee replacement, this surgery has a shorter recovery time, provides a greater range of motion and better knee function, a more natural gait, superior kinematics, and fewer complications.

[0003] However, existing devices do not address the issue of relying solely on experience and anatomical relationships to locate the intramedullary positioning rod in the femur during unicompartmental arthroplasty, which inherently involves subjectivity. This leads to the femoral condyle prosthesis being prone to varus or valgus placement, as the spacer moves excessively with the femoral condyle prosthesis. Varus or valgus placement of the femoral condyle prosthesis can cause spacer dislocation and accelerate prosthesis wear. During osteotomy, continuous shaking of the guide plate can cause Kirschner wires to loosen or even fall off, resulting in loosening of the guide plate itself and affecting surgical efficiency. When drilling through the femoral medullary opening device, the drilling depth cannot be observed, leading to excessively deep drilling. Therefore, we propose a novel device to address these issues. Utility Model Content

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides a 3D-printed guide plate for the unicompartmental femur, which solves the problem that the placement of the unicompartmental femoral condyle prosthesis is prone to inversion or eversion, and that the drilling depth cannot be sensed when drilling with a femoral medullary opening device.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, this utility model provides the following technical solution: a 3D-printed femoral guide plate for unicompartmental joints, comprising a guide plate body, a distal femoral prosthesis locking hole on one side of the guide plate body, a proximal femoral prosthesis locking hole on one side of the guide plate body, a guide plate fixing hole on one side of the guide plate body, an outer guide plate clamping device on one side of the guide plate body, an inner guide plate clamping device on the other side of the guide plate body, a posterior femoral condyle osteotomy groove inside the guide plate body, a posterior femoral condyle clamping device on the lower surface of the guide plate body, a distal limiting group at one end of the distal femoral prosthesis locking hole, a proximal limiting group at one end of the proximal femoral prosthesis locking hole, a positioning hose at one end of the guide plate fixing hole, a threaded locking rod sleeved on the surface of the positioning hose, and a nut threaded through the surface of the threaded locking rod.

[0008] Optionally, the distal limiting assembly includes a distal fixing rod, a distal bolt, a distal moving rod, and a distal spring telescopic rod. The distal bolt is threaded through the interior of the distal fixing rod, the distal moving rod is slidably connected to the interior of the distal fixing rod, and the distal spring telescopic rod is fixedly connected to the interior of the distal moving rod.

[0009] Optionally, the distal fixed rod has a fixed groove inside, and the distal fixed rod is slidably connected to the distal moving rod through the fixed groove.

[0010] Optionally, the surface of the distal fixing rod is provided with a plurality of fixing threaded holes from left to right, and the fixing threaded holes are adapted to the distal spring telescopic rod.

[0011] Optionally, the proximal limiting assembly includes a proximal fixing rod, a proximal bolt, a proximal moving rod, and a proximal spring telescopic rod. The proximal bolt is threaded through the internal thread of the proximal fixing rod. The proximal moving rod is slidably connected to the internal thread of the proximal fixing rod, and the proximal spring telescopic rod is fixedly connected to the internal thread of the proximal moving rod.

[0012] Optionally, the proximal fixing rod has a mating groove inside, and the proximal fixing rod is slidably connected to the proximal moving rod through the mating groove.

[0013] Optionally, the surface of the proximal fixing rod is provided with a plurality of mating threaded holes from left to right, and the mating threaded holes are adapted to the proximal spring telescopic rod.

[0014] Optionally, the proximal locking hole of the distal femoral prosthesis is located on one side of the guide plate body near the middle, and the distal locking hole of the distal femoral prosthesis is located on one side of the guide plate body near the upper part.

[0015] In summary, the technical effects and advantages of this utility model are as follows:

[0016] 1. This utility model has a reasonable structure. Preoperative knee CT scanning and 3D guide plate design are used. During use, the guide plate is clamped on the outer side, the inner side, and the posterior femoral condyle for template clamping. After preoperative template clamping, Kirschner wires are inserted into the guide plate fixation holes to enhance the stability of the guide plate body and prevent loosening during osteotomy. During posterior femoral condyle osteotomy, a curved lever is used on the outer side to protect the medial collateral ligament, and a closed structure is used on the inner side to protect the anterior and posterior cruciate ligaments. This design allows for effective movement of the oscillating saw during osteotomy while preventing damage to ligaments and surrounding tissues. The guide plate body can be removed by removing the Kirschner wires from the guide plate fixation holes. After the guide plate body is fixed, the femoral medullary opening device is used to drill holes in the distal locking hole and proximal locking hole of the distal femoral prosthesis. The distal locking hole and proximal locking hole of the distal femoral prosthesis are designed to protrude to limit the drilling depth and prevent excessive medullary opening or rotation. This ensures that the preoperative drilling position aligns with the intraoperative drilling position, achieving an ideal placement for the femoral prosthesis. It reduces the subjective nature of intramedullary positioning rods in unicompartmental femoral condyle surgery, which rely solely on experience and anatomical relationships. This subjective approach can lead to varus or valgus placement of the femoral condyle prosthesis, as the spacer moves excessively with the prosthesis. Varus or valgus placement can cause spacer dislocation and accelerate prosthesis wear. The guide plate design positions the medial, lateral, and posterior aspects of the medial femoral condyle. The guide plate, designed according to the femoral condyle morphology, allows for dual-column positioning of the femoral condyle prosthesis while simultaneously performing posterior condyle osteotomy. This eliminates the need for intramedullary femoral condyle positioning, reducing patient injury and surgical time. More precise femoral condyle prosthesis positioning avoids adverse consequences caused by varus or valgus placement, reduces surgical steps, lowers surgical difficulty, and minimizes the learning curve.

[0017] 2. In this utility model, by passing the Kirschner wire through the positioning hose until the guide plate body is fixed, and then rotating the nut to compress the positioning hose, the threaded locking rod and the positioning hose lock and fix the Kirschner wire. This reduces the continuous shaking of the guide plate body during osteotomy, which could lead to the Kirschner wire loosening or even falling off, thus affecting the efficiency of the surgery. It achieves the effect of tightening the nut after fixing the Kirschner wire, allowing the threaded locking rod and positioning hose to lock and fix the Kirschner wire. Based on the required drilling depth, the distal bolt of the required depth is removed, leaving a suitable distal threaded hole. By passing one end of the femoral medullary canal device through the distal moving rod, the distal moving rod moves parallel due to the depth of the drilling until the distal spring telescopic rod is released. Pressure is applied through the distal threaded hole, preventing the distal moving rod and femoral opening device from penetrating further. Based on the required drilling depth, the proximal bolt of the desired depth is removed, leaving a suitable proximal threaded hole. By penetrating one end of the femoral opening device through the proximal moving rod, the proximal moving rod moves parallel due to the drilling depth until the proximal spring telescopic rod releases pressure and penetrates the proximal threaded hole, preventing the proximal moving rod and femoral opening device from penetrating further. This reduces the risk of drilling too deeply when drilling through the femoral opening device because the drilling depth cannot be seen. It achieves the effect of limiting the femoral opening device after reaching the desired depth by connecting it to the distal and proximal moving rods, preventing further drilling. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] Figure 2 This is a schematic diagram of the guide plate body structure of this utility model;

[0020] Figure 3 This is a schematic diagram of the exploded structure of the distal fixing rod of this utility model;

[0021] Figure 4 This is a schematic diagram of the exploded structure of the proximal fixing rod of this utility model;

[0022] Figure 5 This is a schematic diagram of the positioning hose structure of this utility model.

[0023] In the diagram: 1. Guide plate body; 2. Distal locking hole of distal femoral prosthesis; 3. Proximal locking hole of distal femoral prosthesis; 4. Guide plate fixation hole; 5. Lateral clamping of guide plate; 6. Medial clamping of guide plate; 7. Posterior femoral condyle osteotomy groove; 8. Posterior femoral condyle clamping; 9. Distal limiting assembly; 901. Distal fixation rod; 902. Distal bolt; 903. Distal movement rod; 904. Distal spring telescopic rod; 10. Proximal limiting assembly; 1001. Proximal fixation rod; 1002. Proximal bolt; 1003. Proximal movement rod; 1004. Proximal spring telescopic rod; 11. Positioning hose; 12. Threaded locking rod; 13. Nut. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] Example: Reference Figures 1-5 The 3D-printed guide plate for the unicompartmental femoral joint shown includes a guide plate body 1. One side of the guide plate body 1 has a distal femoral prosthesis locking hole 2, and the other side has a proximal femoral prosthesis locking hole 3. The guide plate body 1 also has a guide plate fixing hole 4. One side of the guide plate body 1 has a guide plate outer clamping 5, and the other side has a guide plate inner clamping 6. The inside of the guide plate body 1 has a femoral posterior condyle osteotomy groove 7. The lower surface of the guide plate body 1 has a femoral posterior condyle clamping 8. One end of the distal femoral prosthesis locking hole 2 has a distal limiting group 9, and one end of the proximal femoral prosthesis locking hole 3 has a proximal limiting group 10. One end of the guide plate fixing hole 4 has a positioning hose 11. A threaded locking rod 12 is sleeved on the surface of the positioning hose 11, and a nut 13 is threaded through the surface of the threaded locking rod 12.

[0026] As a preferred embodiment of this example, Figure 1 and Figure 2As shown, a distal femoral prosthesis locking hole 2 is provided on one side of the guide plate body 1, and a proximal femoral prosthesis locking hole 3 is provided on the other side of the guide plate body 1. The proximal femoral prosthesis locking hole 3 is located near the middle on one side of the guide plate body 1, and the distal femoral prosthesis locking hole 2 is located near the upper part on one side of the guide plate body 1. A guide plate fixation hole 4 is provided on one side of the guide plate body 1, an outer guide plate clamping 5 is provided on one side of the guide plate body 1, and an inner guide plate clamping 6 is provided on the other side of the guide plate body 1. A posterior femoral condyle osteotomy groove 7 is provided inside the guide plate body 1, and a posterior femoral condyle clamping 8 is provided on the lower surface of the guide plate body 1. During use, by using a knee CT scan and 3D guide plate design before surgery, the outer guide plate clamping 5, the inner guide plate clamping 6, and the posterior femoral condyle clamping 8 are clamped by templates during use. After preoperative preparation and template clamping, Kirschner wires are inserted into the guide plate fixation hole 4 to strengthen the stability of the guide plate body 1 and prevent loosening during osteotomy. During the posterior femoral condyle osteotomy, a curved lever is used on the lateral side to protect the medial collateral ligament, while a closed structure protects the anterior and posterior cruciate ligaments on the medial side. This design allows for effective movement of the oscillating saw during osteotomy while preventing damage to ligaments and surrounding tissues. The guide plate body 1 can be removed by removing the Kirschner wires from the guide plate fixation hole 4. After the guide plate body 1 is fixed, a femoral medullary canal opening device is used to drill holes in the distal femoral prosthesis locking hole 2 and the proximal femoral prosthesis locking hole 3. The distal femoral prosthesis locking holes 2 and 3 are designed to protrude to limit drilling depth and prevent excessive medullary canal opening or rotation. This ensures that the preoperative drilling position aligns with the intraoperative drilling position, achieving an ideal placement for the femoral prosthesis. It reduces the subjective nature of intramedullary positioning rods in unicompartmental femoral condyle surgery, which rely solely on experience and anatomical relationships. This subjective approach can lead to varus or valgus placement of the femoral condyle prosthesis, as the spacer moves excessively with the prosthesis. Varus or valgus placement can cause spacer dislocation and accelerate prosthesis wear. The guide plate design positions the medial, lateral, and posterior aspects of the medial femoral condyle. The guide plate, designed according to the femoral condyle morphology, allows for dual-column positioning of the femoral condyle prosthesis while simultaneously performing posterior condyle osteotomy. This eliminates the need for intramedullary femoral condyle positioning, reducing patient injury and surgical time. More precise femoral condyle prosthesis positioning avoids adverse consequences caused by varus or valgus placement, reduces surgical steps, lowers surgical difficulty, and minimizes the learning curve.

[0027] like Figures 3-5As shown, in this embodiment, one end of the distal locking hole 2 of the distal femoral prosthesis is provided with a distal limiting group 9. The distal limiting group 9 includes a distal fixing rod 901, a distal bolt 902, a distal moving rod 903, and a distal spring telescopic rod 904. The distal bolt 902 passes through the internal thread of the distal fixing rod 901. The distal moving rod 903 is slidably connected inside the distal fixing rod 901. A fixing groove is opened inside the distal fixing rod 901, and the distal fixing rod 901 is slidably connected to the distal moving rod 903 through the fixing groove. The distal spring telescopic rod 904 is fixedly connected inside the distal moving rod 903. Multiple fixing threaded holes are opened sequentially from left to right on the surface of the distal fixing rod 901, and the fixing threaded holes are adapted to the distal spring telescopic rod 904. The distal femoral prosthesis has a proximal limiting assembly 10 at one end of the proximal locking hole 3. The proximal limiting assembly 10 includes a proximal fixing rod 1001, a proximal bolt 1002, a proximal moving rod 1003, and a proximal spring telescopic rod 1004. The proximal bolt 1002 passes through the internal thread of the proximal fixing rod 1001. The proximal moving rod 1003 is slidably connected inside the proximal fixing rod 1001. A mating groove is formed inside the proximal fixing rod 1001, allowing it to slidably connect to the proximal moving rod 1003 via the mating groove. The proximal spring telescopic rod 1004 is fixedly connected inside the proximal moving rod 1003. Multiple mating threaded holes are sequentially formed on the surface of the proximal fixing rod 1001 from left to right, and these threaded holes connect to the proximal spring telescopic rod 1004. The spring telescopic rod 1004 is adapted to the guide plate fixing hole 4, and a positioning hose 11 is provided at one end. A threaded locking rod 12 is sleeved on the surface of the positioning hose 11, and a nut 13 is threaded through the surface of the threaded locking rod 12. During use, the Kirschner wire is passed through the positioning hose 11 until the guide plate body 1 is fixed. After fixing, the nut 13 is rotated to compress the positioning hose 11 with the threaded locking rod 12, thereby locking and fixing the Kirschner wire with the threaded locking rod 12 and the positioning hose 11. This reduces the continuous shaking of the guide plate body 1 during osteotomy, which could cause the Kirschner wire to loosen or even fall off, thus affecting the efficiency of the operation. It achieves the goal of tightening the nut 13 after fixing the Kirschner wire, so that the threaded locking rod 12 and the positioning hose 11 can lock and fix the Kirschner wire. To achieve the locking and fixing effect, based on the required drilling depth, remove the distal bolt 902 to the required depth, leaving a suitable distal threaded hole. By inserting one end of the femoral opening device through the distal moving rod 903, the distal moving rod 903 moves parallel due to the deepening of the drilling until the distal spring telescopic rod 904 releases pressure and passes through the distal threaded hole, preventing further penetration of the distal moving rod 903 and the femoral opening device. Based on the required drilling depth, remove the proximal bolt 1002 to the required depth, leaving a suitable proximal threaded hole. By inserting one end of the femoral opening device through the proximal moving rod 1003, the proximal moving rod 1003 moves parallel due to the deepening of the drilling until the proximal spring telescopic rod 1004 releases pressure and passes through the proximal threaded hole.This design prevents the proximal moving rod 1003 and the femoral opening device from penetrating deeper, reducing the risk of excessive drilling due to the inability to visualize the drilling depth when using the femoral opening device. It achieves the effect of limiting further drilling after reaching the desired depth by connecting the femoral opening device to the distal moving rod 903 and the proximal moving rod 1003.

[0028] The working principle of this practical application is as follows:

[0029] During operation, a 3D guide plate is designed using a preoperative knee CT scan. The guide plate is then secured using the lateral clamping (5), medial clamping (6), and posterior femoral condyle clamping (8) templates. After preoperative template clamping, Kirschner wires are inserted through the guide plate fixation holes (4) to enhance the stability of the guide plate body (1) and prevent loosening during osteotomy. The posterior femoral condyle osteotomy groove (7) is used for posterior femoral condyle osteotomy. During the procedure, a curved lever is used laterally to protect the medial collateral ligament, while a closed structure protects the anterior and posterior cruciate ligaments medially. This design allows for effective movement of the oscillating saw during osteotomy while preventing damage to ligaments and surrounding tissues. The guide plate body (1) can be removed by removing the Kirschner wires from the guide plate fixation holes (4). After the guide plate body 1 is fixed, the femoral medullary canal opening device is used to drill holes in the distal locking hole 2 and proximal locking hole 3 of the distal femoral prosthesis. The distal locking holes 2 and 3 are designed to protrude to limit the drilling depth and prevent excessive medullary canal opening or rotation. This ensures that the preoperatively designed drilling position aligns with the intraoperative drilling position, achieving an ideal placement for the femoral prosthesis. Kirschner wires are passed through the positioning tubing 11 until the guide plate body 1 is fixed. After fixing, the nut 13 is rotated to compress the threaded locking rod 12 against the positioning tubing 11, thereby locking the Kirschner wires in place. Depending on the required drilling depth, the distal bolt 902 is removed to create a suitable distal threaded hole. One end of the femoral medullary canal opening device is then passed through the distal moving rod 903. Due to the depth of the drilling... The distal moving rod 903 is moved parallel until the distal spring telescopic rod 904 releases pressure and penetrates the distal threaded hole, preventing the distal moving rod 903 and the femoral opener from penetrating further. Based on the required drilling depth, the proximal bolt 1002 of the required depth is removed, leaving a suitable proximal threaded hole. One end of the femoral opener is then passed through the proximal moving rod 1003. Due to the depth of the drilling, the proximal moving rod 1003 is moved parallel until the proximal spring telescopic rod 1004 releases pressure and penetrates the proximal threaded hole, preventing the proximal moving rod 1003 and the femoral opener from penetrating further.

[0030] All electrical components mentioned in this article are connected to an external main controller and 220V AC mains power, and the main controller can be a conventional known device such as a computer that can control it.

[0031] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A 3D-printed guide plate for the femur of a unicompartmental joint, comprising a guide plate body (1), characterized in that: One side of the guide plate body (1) is provided with a distal femoral prosthesis locking hole (2), and the other side of the guide plate body (1) is provided with a proximal femoral prosthesis locking hole (3). A guide plate fixing hole (4) is provided on one side of the guide plate body (1). An outer guide plate clamping device (5) is provided on one side of the guide plate body (1), and an inner guide plate clamping device (6) is provided on the other side of the guide plate body (1). A posterior femoral condyle osteotomy groove (7) is provided inside the guide plate body (1). The lower surface of the guide plate body (1) is provided with a femoral condyle clamping (8), one end of the distal locking hole (2) of the distal femoral prosthesis is provided with a distal limiting group (9), one end of the proximal locking hole (3) of the distal femoral prosthesis is provided with a proximal limiting group (10), one end of the guide plate fixing hole (4) is provided with a positioning hose (11), the surface of the positioning hose (11) is sleeved with a threaded locking rod (12), and the threaded locking rod (12) is threaded with a nut (13).

2. The 3D-printed guide plate for the unicompartmental femur according to claim 1, characterized in that: The distal limiting assembly (9) includes a distal fixing rod (901), a distal bolt (902), a distal moving rod (903), and a distal spring telescopic rod (904). The distal bolt (902) is threaded through the interior of the distal fixing rod (901). The distal moving rod (903) is slidably connected to the interior of the distal fixing rod (901). The distal spring telescopic rod (904) is fixedly connected to the interior of the distal moving rod (903).

3. The unicompartmental femoral 3D-printed guide plate according to claim 2, characterized in that: The distal fixed rod (901) has a fixed groove inside, and the distal fixed rod (901) is slidably connected to the distal moving rod (903) through the fixed groove.

4. The 3D-printed guide plate for the unicompartmental femur according to claim 2, characterized in that: The surface of the distal fixing rod (901) is provided with a plurality of fixing threaded holes from left to right, and the fixing threaded holes are adapted to the distal spring telescopic rod (904).

5. The 3D-printed guide plate for the unicompartmental femur according to claim 1, characterized in that: The proximal limiting assembly (10) includes a proximal fixing rod (1001), a proximal bolt (1002), a proximal moving rod (1003), and a proximal spring telescopic rod (1004). The proximal bolt (1002) is threaded through the internal thread of the proximal fixing rod (1001). The proximal moving rod (1003) is slidably connected to the internal thread of the proximal fixing rod (1001). The proximal spring telescopic rod (1004) is fixedly connected to the internal thread of the proximal moving rod (1003).

6. The 3D-printed guide plate for the unicompartmental femur according to claim 5, characterized in that: The proximal fixing rod (1001) has a mating groove inside, and the proximal fixing rod (1001) is slidably connected to the proximal moving rod (1003) through the mating groove.

7. The 3D-printed guide plate for the unicompartmental femur according to claim 5, characterized in that: The surface of the proximal fixing rod (1001) is provided with a plurality of mating threaded holes from left to right, which are adapted to the proximal spring telescopic rod (1004).

8. The 3D-printed guide plate for the unicompartmental femur according to claim 1, characterized in that: The proximal locking hole (3) of the distal femoral prosthesis is located on one side of the guide plate body (1) near the middle, and the distal locking hole (2) of the distal femoral prosthesis is located on one side of the guide plate body (1) near the upper part.

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