A femoral external rotation osteotomy positioning device and a method of using the same

Abstract

The present invention relates to the technical field of medical auxiliary equipment, and specifically discloses a femoral external rotation osteotomy positioning device and a method of using the same; wherein the femoral external rotation osteotomy positioning device comprises a mounting buckle, a positioning plate and a plurality of positioning columns; the mounting buckle and the positioning column are respectively arranged near the two ends of the positioning plate; the movable ends of the positioning columns extend toward the lower end surface of the positioning plate, and the plane formed by the connecting lines of the movable ends of all the positioning columns is parallel to the plane where the positioning plate is located. The mounting buckle in the femoral external rotation osteotomy positioning device can be installed on the external rotation osteotomy guide plate provided by different prosthesis manufacturers, and cooperate with the external rotation osteotomy guide plate to adjust the external rotation position, so as to accurately determine the external rotation osteotomy position, so that the distal end of the femur can be adapted to the prosthesis after the external rotation osteotomy, thereby ensuring a good flexion gap and patellar trajectory after total knee replacement, restoring knee joint function and extending the service life of the prosthesis.

Description

Technical Field

[0001] The invention belongs to the technical field of medical auxiliary equipment, and in particular relates to a femoral external rotation osteotomy positioning device and a use method thereof. Background Art

[0002] Total knee arthroplasty (TKA) is an effective method for treating severe knee osteoarthritis. The surgery replaces the diseased knee joint with a prosthesis to help patients restore joint function and relieve pain.

[0003] Among them, femoral prosthesis rotation alignment is considered to be one of the most important factors affecting functional recovery and prosthesis survival after total knee replacement. It mainly affects the flexion gap and patellar trajectory after total knee replacement, and ultimately affects the joint function and prosthesis service life after total knee replacement.

[0004] At present, in total knee replacement surgery, surgeons often need to use the anatomical landmarks of the distal femur and the reference axes they form to determine the rotation alignment of the femoral prosthesis. Commonly used reference axes include: the anterior-posterior femoral axis (Whiteside line), the posterior femoral condylar axis (PCL), and the lateral epicondylar axis (TEA).

[0005] However, in actual operation, the above-mentioned multiple axes (reference axes) are easily affected by the proliferation of osteophytes or the wear of the distal femur, resulting in errors in the reference axis position. If osteotomy is performed directly with reference to the reference axis, a certain error will occur, which will make it difficult for the prosthesis to match the femoral external rotation osteotomy position, affecting the joint function and prosthesis service life after total knee replacement. Therefore, inventing a device and method that can accurately determine the osteotomy position is a technical problem that needs to be solved by those skilled in the art. Summary of the invention

[0006] The present invention provides a femoral external rotation osteotomy positioning device to solve the technical problem in the prior art that the reference axis is easily affected by the proliferation of osteophytes or the wear of the distal end of the femur, resulting in errors in the position of the reference axis, making it difficult for the femoral external rotation osteotomy position to adapt to the prosthesis, resulting in the joint function and the service life of the prosthesis being affected after total knee replacement.

[0007] The present invention is achieved through the following technical solutions:

[0008] A femoral external rotation osteotomy positioning device, comprising a mounting buckle, a positioning sheet and a positioning column;

[0009] The mounting buckle is arranged at the fixed end of the positioning piece;

[0010] The number of the positioning posts is at least three, all of the positioning posts are arranged close to the positioning end of the positioning piece, the movable ends of the positioning posts extend toward the lower end surface of the positioning piece, and the plane surrounded by the connecting line of the movable ends of all the positioning posts is parallel to the plane where the positioning piece is located;

[0011] A bayonet is provided on one side of the mounting buckle facing the positioning column, and the mounting buckle can be detachably connected to the external rotation osteotomy guide plate through the bayonet.

[0012] In order to better realize the present invention, further optimization is made in the above structure, and the femoral external rotation osteotomy positioning device also includes an adjustment plate;

[0013] All of the positioning columns are vertically arranged on the adjustment plate;

[0014] The positioning piece is provided with a plurality of through holes, and the setting positions of the plurality of through holes correspond one-to-one to the setting positions of the plurality of positioning posts. The movable end of the positioning post can extend from the upper end surface of the positioning piece through the through holes to the lower end surface of the positioning piece.

[0015] In order to better implement the present invention, further optimization is made in the above structure, and the positioning column and the through hole are interference fit.

[0016] In order to better implement the present invention, further optimization is made in the above structure, and scale marks are arranged on the positioning column, and the scale marks are arranged from the movable end of the positioning column to the fixed end of the positioning column.

[0017] On the other hand, the present invention further provides a method for using the femoral external rotation osteotomy positioning device based on the above-mentioned femoral external rotation osteotomy positioning device. The method is implemented by the above-mentioned femoral external rotation osteotomy positioning device, and the method comprises the following steps:

[0018] Determine a reference plane, the reference plane being determined by two points 2 cm apart on the cartilage boundary in front of the medial femoral condyle and a point 3 cm away from the cartilage boundary on the midline of the anterior cortex of the femoral shaft;

[0019] The mounting buckle in the femoral external rotation osteotomy positioning device is mounted on the external rotation osteotomy guide plate, so that the plane where the positioning piece is located is perpendicular to the plane where the external rotation osteotomy guide plate is located, and the length direction of the external rotation osteotomy guide plate is parallel to the plane where the positioning piece is located;

[0020] Fit the working surface of the external rotation osteotomy guide plate onto the cut surface of the distal femur;

[0021] The external rotation osteotomy guide plate is externally rotated or internally rotated so that the movable ends of all the positioning columns contact the reference plane to determine the osteotomy position.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The mounting buckle in the femoral external rotation osteotomy positioning device provided by the present invention can be installed on the external rotation osteotomy guide plates provided by different prosthesis manufacturers. When in use, the external rotation osteotomy guide plate installed with the femoral external rotation osteotomy positioning device is fitted onto the cross-section of the distal end of the femur, so that the positioning end of the positioning plate extends to the reference plane, and the relative position of the positioning plate and the reference plane is determined by the positioning column, so as to achieve the adjustment of the external rotation position of the external rotation osteotomy guide plate, so as to accurately determine the external rotation osteotomy position, so that the distal end of the femur can be adapted to the prosthesis after the external rotation osteotomy, thereby ensuring that the flexion gap and patellar trajectory are good after total knee replacement, restoring the knee joint function and extending the service life of the prosthesis. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a structural schematic diagram of a femoral external rotation osteotomy positioning device provided by the present invention;

[0026] Figure 2 It is a structural schematic diagram of a state in which a positioning plate and a positioning column are separated in a femoral external rotation osteotomy positioning device provided by the present invention;

[0027] Figure 3 It is a structural schematic diagram of a femoral external rotation osteotomy positioning device provided by the present invention when it cooperates with an external rotation osteotomy guide plate;

[0028] Figure 4 It is a side view of a femoral external rotation osteotomy positioning device provided by the present invention when in use;

[0029] Figure 5 It is a schematic diagram of the position of the reference surface recorded in the embodiment.

[0030] In the figure:

[0031] 1. Install the buckle;

[0032] 2. Positioning piece; 21. Perforation;

[0033] 3. Adjustment plate;

[0034] 4. Positioning column;

[0035] 5. External rotation osteotomy guide. DETAILED DESCRIPTION

[0036] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0037] In the description of the present invention, it should be noted that, unless otherwise specified, the meaning of "plurality" is two or more; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0038] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] At present, the commonly used femoral prosthesis rotation alignment reference axes in total knee replacement surgery include the femoral epicondylar axis (TEA), the posterior femoral condylar axis (PCL), the anterior-posterior axis (AP; Whiteside line), and the anterior femoral axis (AFA); among them,

[0040] The femoral medial and lateral epicondylar axis is divided into surgical femoral medial and lateral epicondylar axis (sTEA) and clinical femoral medial and lateral epicondylar axis (cTEA); sTEA is defined as the line connecting the most protruding point of the lateral femoral epicondyle and the medial femoral epicondyle groove, while cTEA is defined as the line connecting the most protruding points of the lateral and lateral femoral epicondyles.

[0041] However, it is difficult to determine the most convex position in actual operation, making it difficult to use the medial and lateral epicondylar axis of the femur as the reference axis for positioning during surgery. When osteophytes are formed at the medial and lateral epicondylar locations, it will interfere with the confirmation of the axis position.

[0042] The posterior condylar axis (PCL) refers to the line connecting the most convex points of the medial and lateral sides of the posterior femoral condyle. Generally, the surgeon will rotate 3° counterclockwise along the PCL before performing osteotomy on the posterior femoral condyle.

[0043] However, due to the destruction, excessive wear and even degeneration of the posterior femoral condyle, contracture of the soft tissues at the posterior knee joint and the formation of osteophytes at the posterior femoral condyle, the reference position will change significantly. If the lateral femoral condyle is worn more severely, insufficient internal rotation will occur after surgery; if the medial condyle is worn more severely, excessive internal rotation osteotomy will occur. Therefore, it cannot be used as an accurate landmark for rotation alignment.

[0044] The anterior-posterior axis (AP; Whiteside line) is a line drawn from the lowest point of the femoral trochlear groove to the center of the intercondylar fossa when the knee is flexed 90°; when the posterior femoral condyle is hypoplastic or has a bone defect, this line is a more reliable reference and is not affected by valgus or varus deformity of the knee.

[0045] However, in patients with severe osteoarthritis or dysplasia of the distal femoral condyle, osteotomy based on this axis will result in a certain error. In revision, this line does not exist, and the variability is large in healthy people. At the same time, if hypertrophic osteophytes form in the intercondylar fossa, this axis is difficult to measure.

[0046] The anterior femoral axis (AFA) is the tangent line of the anterior femoral plane proximal to the femoral trochlear cartilage surface. Some researchers have found that the AFA can be obtained by rotating the perpendicular line of the anterior-posterior axis 3° counterclockwise, which is considered to be one of the methods to determine the femoral rotation alignment.

[0047] However, recent studies have shown that there are significant differences in the stability of the anterior femoral axis relative to the lateral and medial femoral epicondylar axis and the variability of the anterior femoral axis relative to the lateral and medial femoral epicondylar axis.

[0048] In summary, if the above axis is directly used as the reference axis for osteotomy, a certain error will occur, which will make it difficult for the prosthesis to match the femoral osteotomy position, affecting the joint function and prosthesis service life after total knee replacement.

[0049] In view of the above situation, the inventors found that there is a reference plane on the cortical surface of the anterior bone of the medial femoral condyle, see Figure 5 The reference plane is composed of two points 2 cm apart on the anterior cartilage boundary of the medial femoral condyle ( Figure 5 A and B in the figure) and a point 3 cm from the cartilage border on the midline of the anterior cortex of the femoral shaft ( Figure 5 The plane determined by the reference plane is parallel to the surgical femoral condyle line, that is, the plane tangent of the reference plane is parallel to the plane where the side wall of the prosthesis groove is located, and the reference plane is located on the upper end surface of the patella on the femoral trochlea, which is easy to confirm and touch. At the same time, this position will not be affected by osteophytes, wear and maldevelopment, etc., and can be used as a reference for osteotomy.

[0050] Based on the above reference plane, an embodiment of the present invention provides a femoral external rotation osteotomy positioning device, such as Figures 1 to 4 As shown, it includes a mounting buckle 1, a positioning piece 2 and a positioning column 4; wherein,

[0051] The mounting buckle 1 is arranged at the fixed end of the positioning piece 2;

[0052] The number of positioning columns 4 is at least three. In this embodiment, three positioning columns 4 are taken as an example for explanation. The three positioning columns 4 are all arranged close to the positioning end of the positioning plate 2. The movable ends of the positioning columns 4 extend toward the lower end surface of the positioning plate 2. The plane surrounded by the connecting lines of the movable ends of the three positioning columns 4 is parallel to the plane where the positioning plate 2 is located.

[0053] Before performing femoral external rotation osteotomy, the surgeon can install the femoral external rotation osteotomy positioning device on the external rotation osteotomy guide plate 5 through the mounting buckle 1, and make the positioning end of the positioning piece 2 be located on one side of the working surface of the external rotation osteotomy guide plate 5. In this state, the osteotomy groove on the external rotation osteotomy guide plate 5 is parallel to the plane where the positioning piece 2 is located.

[0054] Then, the surgeon can fit the working surface of the external rotation osteotomy guide plate 5 onto the osteotomy surface of the distal femur of the patient, see Figure 4 , rotate the external rotation osteotomy guide plate 5 around the axis of the patient's femur length, so that the active ends of all the positioning columns 4 are in contact with the above-mentioned reference plane, to ensure that the plane where the positioning piece 2 is located and the osteotomy groove are parallel to the reference plane;

[0055] At this time, the surgeon can fix the external rotation osteotomy guide plate 5, remove the femoral external rotation osteotomy positioning device, and then extend the osteotomy saw blade into the osteotomy groove, perform osteotomy along the length direction of the osteotomy groove, cut off the anterior condyle of the distal femur, and establish an adaptation plane;

[0056] Based on the adaptation plane, other osteotomy tools are used to resect the posterior condyle of the distal femur, so that the distal femur can adapt to the prosthesis after external rotation osteotomy, thereby ensuring a good flexion gap and patellar trajectory after total knee replacement, restoring function and extending the service life of the prosthesis.

[0057] It should be noted that the positioning column 4 is a cylindrical structure, and the movable end of the positioning column 4 is a plane. The surgeon can determine the positional relationship between the positioning piece 2 and the reference plane by checking whether the plane of the movable end of the positioning column 4 is in contact with the reference plane, so as to make the use of the femoral external rotation osteotomy positioning device more convenient;

[0058] The above-mentioned external rotation osteotomy guide plate 5 is an external rotation osteotomy guide plate provided by different prosthesis manufacturers in the prior art, and the mounting buckle 1 in the femoral external rotation osteotomy positioning device can be adapted thereto.

[0059] In some embodiments, the above-mentioned mounting buckle 1 is arranged on the lower end surface of the positioning piece 2, and a bayonet is arranged on the side of the mounting buckle 1 facing the positioning column 4, see Figure 1 and Figure 2 The mounting buckle 1 can be detachably connected to the external rotation osteotomy guide plate 5 through the bayonet, thereby making the installation and disassembly of the femoral external rotation osteotomy positioning device more convenient.

[0060] Preferably, the width of the bayonet matches the distance from the osteotomy groove in the external rotation osteotomy guide plate 5 to the upper end surface of the external rotation osteotomy guide plate 5;

[0061] When installing the femoral external rotation osteotomy positioning device, the mounting buckle 1 can be clamped in the portion between the osteotomy groove and the upper end surface of the external rotation osteotomy guide plate 5 through the bayonet, see Figure 3 This arrangement makes the installation and disassembly of the femoral external rotation osteotomy positioning device and the external rotation osteotomy guide plate 5 more convenient, and enables the femoral external rotation osteotomy positioning device to slide on the external rotation osteotomy guide plate 5 along the length direction of the osteotomy groove, so as to adjust the position of the femoral external rotation osteotomy positioning device.

[0062] It should be noted that the above-mentioned mounting buckle 1 and the external rotation osteotomy guide plate 5 are interference fit, that is, when the femoral external rotation osteotomy positioning device is installed on the external rotation osteotomy guide plate 5, the position of the femoral external rotation osteotomy positioning device will not change without external force.

[0063] When the position of the femoral external rotation osteotomy positioning device needs to be adjusted, the surgeon needs to push the femoral external rotation osteotomy positioning device with force so that the femoral external rotation osteotomy positioning device can slide along the length direction of the osteotomy groove to adjust the position of the femoral external rotation osteotomy positioning device, thereby avoiding the situation in which the position of the femoral external rotation osteotomy positioning device changes during use and causes an error in the osteotomy position.

[0064] In some embodiments, the femoral external rotation osteotomy positioning device further includes an adjustment plate 3; wherein,

[0065] The three positioning columns 4 are vertically arranged on the adjustment plate 3;

[0066] The positioning sheet 2 is provided with a plurality of through holes 21, and the positions of the plurality of through holes 21 correspond to the positions of the plurality of positioning posts 4. Figure 5 , the movable end of the positioning column 4 can extend from the upper end surface of the positioning piece 2 through the through hole 21 to the lower end surface of the positioning piece 2;

[0067] When it is necessary to adjust the distance between the movable end of the positioning column 4 and the lower end surface of the positioning plate 2, the surgeon can push / pull the adjustment plate 3 to slide the three positioning columns 4 along the axial direction of the through hole 21, so that the positioning end of the positioning plate 2 can extend across the anterior condyle of the patient's femur to the position of the reference plane, see Figure 4 , and when the movable end of the positioning column 4 contacts the reference plane, the positioning plate 2 does not contact the patient's femur, thereby making the determination of the osteotomy plane more accurate.

[0068] Preferably, the above-mentioned positioning column 4 and the through hole 21 are interference fit, that is, the position of the positioning column 4 will not change when no external force is applied; and when it is necessary to adjust the distance between the movable end of the positioning column 4 and the lower end surface of the positioning plate 2, the operator needs to push / pull the adjustment plate 3 with force to adjust the distance between the movable end of the positioning column 4 and the lower end surface of the positioning plate 2.

[0069] In some embodiments, the positioning column 4 is provided with scale marks, which are arranged from the movable end of the positioning column 4 to the fixed end of the positioning column 4, that is, the values ​​of the scale marks increase from the movable end of the positioning column 4 to the fixed end of the positioning column 4;

[0070] The operator can determine the distance between the movable end of the positioning column 4 and the lower end surface of the positioning plate 2 by the numerical value of the scale mark corresponding to the lower end surface of the positioning plate 2, so as to make the use of the femoral external rotation osteotomy positioning device more convenient.

[0071] Based on the above-mentioned femoral external rotation osteotomy positioning device, the present invention also provides a method for using the femoral external rotation osteotomy positioning device, which is implemented by the above-mentioned femoral external rotation osteotomy positioning device, and the method comprises the following steps:

[0072] Determine the reference plane, which is the plane enclosed by the medial femoral condyle, the midpoint of the medial wall of the femoral intercondylar notch, and the midpoint of the line connecting the medial femoral condyle and the femoral shaft;

[0073] The mounting buckle 1 in the femoral external rotation osteotomy positioning device is clamped on the external rotation osteotomy guide plate 5, so that the plane where the positioning piece 2 is located is perpendicular to the plane where the external rotation osteotomy guide plate 5 is located, and the length direction of the external rotation osteotomy guide plate 5 is parallel to the plane where the positioning piece 2 is located;

[0074] Fitting the working surface of the external rotation osteotomy guide plate 5 onto the cut surface of the distal end of the femur;

[0075] Externally rotate or internally rotate the osteotomy guide plate 5 so that the active ends of all the positioning columns 4 contact the reference plane to determine the osteotomy position;

[0076] The surgeon can then perform external rotation osteotomy according to the determined osteotomy position so that the distal end of the femur after external rotation osteotomy can fit the prosthesis, thereby ensuring a good patellar trajectory in total knee replacement, restoring knee joint function and extending the service life of the prosthesis.

[0077] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A femoral external rotation osteotomy positioning device, characterized in that: It comprises a mounting buckle (1), a positioning piece (2) and a positioning column (4); The mounting buckle (1) is arranged at the fixed end of the positioning piece (2); The number of the positioning posts (4) is at least three, all of the positioning posts (4) are arranged close to the positioning end of the positioning piece (2), the movable ends of the positioning posts (4) extend toward the lower end surface of the positioning piece (2), and the plane formed by the connecting line of the movable ends of all the positioning posts (4) is parallel to the plane where the positioning piece (2) is located; A bayonet is provided on one side of the mounting buckle (1) facing the positioning column (4), and the mounting buckle (1) can be detachably connected to the external rotation osteotomy guide plate (5) through the bayonet.

2. The femoral external rotation osteotomy positioning device according to claim 1, characterized in that: Also includes an adjustment plate (3); All of the positioning columns (4) are vertically arranged on the adjustment plate (3); The positioning sheet (2) is provided with a plurality of through holes (21), the arrangement positions of the plurality of through holes (21) correspond one-to-one with the arrangement positions of the plurality of positioning posts (4), and the movable ends of the positioning posts (4) can extend from the upper end surface of the positioning sheet (2) through the through holes (21) to the lower end surface of the positioning sheet (2).

3. The femoral external rotation osteotomy positioning device according to claim 2, characterized in that: The positioning column (4) and the through hole (21) are in interference fit.

4. The femoral external rotation osteotomy positioning device according to claim 2, characterized in that: The positioning column (4) is provided with scale marks, and the scale marks are arranged from the movable end of the positioning column (4) to the fixed end of the positioning column (4).

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