Unicondylar tibial prosthesis

Abstract

The present invention relates to a unicondylar tibial prosthesis. The unicondylar tibial prosthesis includes a tibial tray and a tibial insert. The tibial tray is provided with a receiving groove, and the groove wall of the receiving groove is provided with opposite front end card slots and rear end card slots. The groove wall of the receiving groove is also provided with opposite first side grooves and second side grooves. The tibial insert includes a body and a mounting portion protruding outward from the body. The mounting portion is used for being embedded in the receiving groove. The mounting portion is provided with opposite front end catching positions and rear end catching positions. The mounting portion is also provided with opposite first side catching positions and second side catching positions. The front end catching position is used for being embedded in the front end card slot, the rear end catching position is used for being embedded in the rear end card slot, the first side catching position is used for being embedded in the first side groove, and the second side catching position is used for being embedded in the second side groove. The tibial tray and the tibial insert of the above-mentioned unicondylar tibial prosthesis are engaged through the cooperation of the card slots and catching positions in the front, rear, left, and right four directions, which greatly improves the stability of the tibial prosthesis and reduces the risk of dislocation of the tibial insert from the tibial tray.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly to a unicondylar tibial prosthesis. Background Art

[0002] Unicondylar knee arthroplasty fills the gap between total knee arthroplasty and non-replacement treatment, and completely preserves the biomechanical structure of the knee joint after replacement, better meeting the daily life needs of people. Therefore, unicondylar knee arthroplasty is widely used in the treatment of osteoarthritis at home and abroad. A unicondylar knee prosthesis is a surgical implant used to replace a part of the human knee joint. However, since the knee joint is one of the main weight-bearing joints involved in human movement, in order to ensure that patients can obtain a high level of knee joint mobility after unicondylar knee arthroplasty, the stability of the unicondylar knee prosthesis becomes a factor that must be considered during the prosthesis design process. And the locking between the tibial tray and the tibial insert plays an important role in the stability of the unicondylar knee prosthesis.

[0003] The traditional tibial tray and tibial insert are locked by a front slot and a rear slot, but such a locking method has a risk of dislocation after surgery, affecting the patient's life after surgery and even causing secondary harm to the patient. Summary of the Invention

[0004] Based on this, it is necessary to provide a unicondylar tibial prosthesis for how to reduce the problem of dislocation of the tibial tray and the tibial insert after surgery.

[0005] A unicondylar tibial prosthesis, comprising:

[0006] A tibial tray, the tibial tray is provided with a receiving groove, the groove wall of the receiving groove is provided with opposite front slots and rear slots, and the groove wall of the receiving groove is also provided with opposite first side slots and second side slots; and,

[0007] A tibial insert, the tibial insert includes a body and a mounting portion protruding outward from the body, the mounting portion is used for embedding in the receiving groove, the mounting portion is provided with opposite front locking positions and rear locking positions, the mounting portion is also provided with opposite first side locking positions and second side locking positions, the front locking position is used for being embedded in the front slot, the rear locking position is used for being embedded in the rear slot, the first side locking position is used for being embedded in the first side slot, and the second side locking position is used for being embedded in the second side slot.

[0008] In one embodiment, the first side groove and the second side groove communicate with two ends of the rear end clamping groove respectively. The front end clamping groove has a first length, the first side groove has a second length, and the ratio range of the second length to the first length is 0.01 - 0.7; the second side groove has a third length, and the ratio range of the third length to the first length is 0.01 - 0.7; the front end clamping groove has a fourth length, and the ratio range of the fourth length to the first length is 0.01 - 0.3; the front end clamping groove has a fifth length, and the ratio range of the fifth length to the first length is 0.01 - 0.4.

[0009] In one embodiment, the first side clamping position and the second side clamping position are respectively connected to two ends of the rear end clamping groove. The front end clamping position has a sixth length, the first side clamping position has a seventh length, and the ratio range of the seventh length to the sixth length is 0.01 - 0.9; the second side clamping position has an eighth length, and the ratio range of the eighth length to the sixth length is 0.01 - 0.7; the front end clamping position has a ninth length, and the ratio range of the ninth length to the sixth length is 0.01 - 0.9; the front end clamping position has a tenth length, and the ratio range of the tenth length to the sixth length is 0.01 - 0.4.

[0010] In one embodiment, a first straight surface is provided on the groove wall of the first side groove, and a second straight surface is provided on the groove wall of the second side groove. The first straight surface is parallel to the second straight surface;

[0011] The first side clamping position is provided with a third straight surface for sliding cooperation with the first straight surface, and the second side clamping position is provided with a fourth straight surface for sliding cooperation with the second straight surface.

[0012] In one embodiment, the ratio range of the length of the line segment formed by the intersection of the second straight surface and the horizontal plane to the third length is 0.01 - 0.8; the ratio range of the length of the line segment formed by the intersection of the fourth straight surface and the horizontal plane to the eighth length is 0.01 - 0.8.

[0013] In one embodiment, a first inclined surface is provided on the groove wall of the first side groove. The first inclined surface is arranged at an acute angle with the bottom wall of the accommodating groove. A second inclined surface is provided on the groove wall of the second side groove. The second inclined surface is arranged at an acute angle with the bottom wall of the accommodating groove;

[0014] The end face of the installation part close to the bottom wall of the accommodation groove is the first end face. The first side engaging position is provided with a third inclined surface, the third inclined surface is arranged at an acute angle with the first end face, and the third inclined surface is used for sliding cooperation with the first inclined surface. The second side engaging position is provided with a fourth inclined surface, the fourth inclined surface is arranged at an acute angle with the first end face, and the fourth inclined surface is used for sliding cooperation with the second inclined surface.

[0015] In one embodiment, the included angle between the first inclined surface and the bottom wall of the accommodation groove ranges from 30° to 85°; the ratio of the length of the line segment formed by the intersection of the second inclined surface and the horizontal plane to the third length ranges from 0.01 to 0.8, and the included angle between the second inclined surface and the bottom wall of the accommodation groove ranges from 30° to 85°; the included angle between the third inclined surface and the first end face ranges from 30° to 85°; the ratio of the length of the line segment formed by the intersection of the fourth inclined surface and the horizontal plane to the seventh length ranges from 0.01 to 0.8, and the included angle between the fourth inclined surface and the first end face ranges from 30° to 85°

[0016] In one embodiment, the edge of the groove wall of the accommodation groove is provided with a first chamfer and a second chamfer, and the extension range of the first chamfer corresponds to the extension range of the front end engaging slot, and the extension range of the second chamfer corresponds to the extension ranges of the rear end engaging slot, the first side slot, and the second side slot; the front end engaging position is provided with a third chamfer, the third chamfer matches the first chamfer, and the rear end engaging position, the first side engaging position, and the second side engaging position are all provided with fourth chamfers, and the fourth chamfers match the second chamfer.

[0017] In one embodiment, the angle of the first chamfer is greater than or equal to the angle of the second chamfer.

[0018] In one embodiment, the tibial tray is provided with a groove, and the groove penetrates through the groove walls of the first side slot and the second side slot.

[0019] By providing the first side slot and the second side slot on the tibial tray and correspondingly providing the first side engaging position and the second side engaging position on the tibial liner, the above-mentioned tibial prosthesis can form a locking structure on both the outer side and the inner side by embedding the first side engaging position in the first side slot and embedding the second side engaging position in the second side slot, greatly improving the shear resistance of the tibial prosthesis in the medial or lateral direction. Compared with the traditional tibial prosthesis that is only locked from the front end and the rear end, the tibial tray and the tibial liner of the present application are engaged through the card slots and engaging positions in the front, rear, left, and right four directions, greatly improving the stability of the tibial prosthesis and reducing the risk of the tibial liner dislocating from the tibial tray. Description of the Drawings

[0020] The accompanying drawings, which form a part of this application, are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0022] Figure 1 Structural schematic diagram of a unicondylar tibial prosthesis of an embodiment;

[0023] Figure 2 For Figure 1 Structural schematic diagram of the tibial tray of the unicondylar tibial prosthesis shown in

[0024] Figure 3 For Figure 2 Structural schematic diagram of the tibial tray shown in from another perspective;

[0025] Figure 4 For Figure 2 Cross-sectional view of the tibial tray shown in in a horizontal section;

[0026] Figure 5 For Figure 2 Cross-sectional view of the tibial tray shown in in a sagittal plane;

[0027] Figure 6 For Figure 1 Structural schematic diagram of the tibial liner of the unicondylar tibial prosthesis shown in ;

[0028] Figure 7 For Figure 6 Structural schematic diagram of the tibial liner shown in from another perspective;

[0029] Figure 8 For Figure 6 Cross-sectional view of the tibial liner shown in in a horizontal section;

[0030] Figure 9 For Figure 6 Cross-sectional view of the tibial liner shown in in a sagittal plane;

[0031] Figure 10 For Figure 1 Structural sectional view of the unicondylar tibial prosthesis shown in ;

[0032] Figure 11 Structural sectional view of a unicondylar tibial prosthesis of another embodiment;

[0033] Figure 12 is Figure 11 a schematic structural view of the tibial tray of the unicompartmental tibial prosthesis shown in

[0034] Figure 13 is Figure 11 a schematic structural view of the tibial insert of the unicompartmental tibial prosthesis shown in

[0035] Figure 14 a schematic structural view of the unicompartmental tibial prosthesis of another embodiment;

[0036] Figure 15 a schematic structural view of the tibial tray of the unicompartmental tibial prosthesis of another embodiment.

[0037] 10. Unicompartmental tibial prosthesis; 11. Tibial tray; 111. Receiving groove; 112. Front end card slot; 113. Rear end card slot; 114. First side groove; 1141. First straight surface; 115. Second side groove; 1151. Second straight surface; 1171. First chamfer; 1172. Second chamfer; 1181. First upper end surface; 1182. First lower end surface; 1183. First inner end surface; 1184. First outer end surface; 12. Tibial insert; 121. Body; 122. Mounting portion; 123. Front end positioning; 124. Rear end positioning; 125. First side positioning; 1251. Third straight surface; 126. Second side positioning; 1261. Fourth straight surface; 127. First end surface; 1271. Third chamfer; 1272. Fourth chamfer; 1281. Second upper end surface; 1282. Second lower end surface; 1283. Second inner end surface; 1284. Second outer end surface; 20. Unicompartmental tibial prosthesis; 21. Tibial tray; 211. Receiving cavity; 2141. First inclined surface; 2151. Second inclined surface; 22. Tibial insert; 2251. Third inclined surface; 2261. Fourth inclined surface; 227. First end surface; 30. Unicompartmental tibial prosthesis; 31. Tibial tray; 311. Receiving groove; 312. First notch; 313. Second notch; 32. Tibial insert. Detailed Embodiments

[0038] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention will be given with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0039] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is 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 thus should not be construed as a limitation on the present invention.

[0040] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0041] In the present invention, unless otherwise clearly specified and limited, the terms "mounted", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "under" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0043] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation.

[0044] To better elaborate on the technical solution of the present invention, first, the orientation names involved in each embodiment are explained:

[0045] Sagittal plane: It refers to a longitudinal section that divides the human body or joint into left and right parts from the front-back direction. Among them, the sagittal plane passing through the midline of the human body is the median sagittal plane, and this plane divides the human body into two equal left and right parts.

[0046] Coronal plane: It refers to a longitudinal section that divides the human body or joint into front and back parts from the left-right direction, and this section is perpendicular to the sagittal plane.

[0047] Horizontal plane: Also known as the transverse section, it is a plane parallel to the ground plane that divides the human body or joint into upper and lower parts, and this plane is perpendicular to the coronal plane and the sagittal plane.

[0048] Medial: The side relatively closer to the median sagittal plane of the human body.

[0049] Lateral: The side relatively farther from the median sagittal plane of the human body.

[0050] Anterior: The side relatively closer to the abdomen on the sagittal plane.

[0051] Posterior: The side relatively closer to the back on the sagittal plane.

[0052] See Figure 1 , the embodiment of the present application provides a unicondylar tibial prosthesis 10. The unicondylar tibial prosthesis 10 shown in FIG. 1 is the tibial prosthesis on the medial side of the left leg of the human body, and its structure is the same as that of the tibial prosthesis outside the right leg of the human body. The tibial prosthesis on the lateral side of the left leg and the tibial prosthesis on the medial side of the right leg are both symmetric with the tibial prosthesis on the medial side of the left leg with respect to the sagittal plane. To make the technical solution of the present invention easier to understand, this embodiment takes the tibial prosthesis on the medial side of the left leg of the human body as an example to elaborate on the unicondylar tibial prosthesis 10 of the present application in detail.

[0053] Specifically, see Figure 1-4, a tibial prosthesis of an embodiment includes a tibial tray 11 and a tibial liner 12. The tibial tray 11 is provided with a receiving groove 111 and a groove wall surrounding the receiving groove 111. The groove wall of the receiving groove 111 is provided with a front end card slot 112 and a rear end card slot 113 which are opposite to each other. The groove wall of the receiving groove 111 is further provided with a first side groove 114 and a second side groove 115 which are opposite to each other. The first side groove 114 and the second side groove 115 are respectively located on the left and right sides of the tibial tray 11. Refer to Figure 6-8 , the tibial liner 12 includes a body 121 and a mounting portion 122 protruding outward from the body 121. The mounting portion 122 is used to be embedded in the receiving groove 111. The mounting portion 122 is provided with a front end catch 123 and a rear end catch 124 which are opposite to each other. The mounting portion 122 is further provided with a first side catch 125 and a second side catch 126 which are opposite to each other. The first side catch 125 and the second side catch 126 are respectively located on the left and right sides of the tibial liner 12. A catch refers to a structure for locking with a card slot, and usually can be a flange extending in the horizontal direction, such as Figure 8 the white edge part in, or can also be a contour shape with a locking function. The front end catch 123 is used to be embedded in the front end card slot 112, the rear end catch 124 is used to be embedded in the rear end card slot 113, the first side catch 125 is used to be embedded in the first side groove 114, and the second side catch 126 is used to be embedded in the second side groove 115.

[0054] Specifically, refer to Figure 2-4 , taking the tibial tray 11 on the inner side of the left leg as an example, the first side groove 114 is opened on the outer groove wall of the receiving groove 111 of the tibial tray 11, and the second side groove 115 is opened on the inner groove wall of the receiving groove 111 of the tibial tray 11 ( Figure 4 the white edge in represents a flange extending in the horizontal direction, and the space between the flange and the bottom wall of the receiving groove 111 until the bottom wall is the card slot). Correspondingly, refer to Figure 6-8 , taking the tibial liner 12 on the inner side of the left leg as an example, the first side catch 125 is arranged on the outer side of the tibial liner 12, and the second side catch 126 is arranged on the inner side of the tibial liner 12.

[0055] The above tibial prosthesis forms a locking structure on both the outer and inner sides by opening a first side groove 114 and a second side groove 115 on the tibial tray 11, and correspondingly arranging a first side clamping position 125 and a second side clamping position 126 on the tibial liner 12. Specifically, by embedding the first side clamping position 125 into the first side groove 114 and embedding the second side clamping position 126 into the second side groove 115, the ability of the tibial prosthesis to resist shear forces in the medial or lateral direction is greatly improved. Compared with traditional tibial prostheses that are only locked from the front and rear, the tibial tray 11 and the tibial liner 12 of this application are clamped through the cooperation of the clamping grooves and clamping positions in the front, rear, left, and right directions, greatly improving the stability of the tibial prosthesis and reducing the risk of dislocation of the tibial liner 12 from the tibial tray 11. Specifically, under the same experimental conditions, the locking force from front to back (referring to the force of pushing the tibial liner 12 from front to back until the tibial liner 12 is disengaged from the tibial tray 11) between the tibial liner 12 provided with the first side clamping position 125 and the second side clamping position 126 and the tibial tray 11 provided with the first side groove 114 and the second side groove 115 is 1.5 - 1.7 times that of the traditional tibial liner 12 and tibial tray 11. The locking force from back to front (referring to the force of pushing the tibial liner 12 from back to front until the tibial liner 12 is disengaged from the tibial tray 11) between the tibial liner 12 provided with the first side clamping position 125 and the second side clamping position 126 and the tibial tray 11 provided with the first side groove 114 and the second side groove 115 is 1.6 - 1.8 times that of the traditional tibial liner 12 and tibial tray 11. The locking force from inside to outside (referring to the force of pushing the tibial liner 12 from inside to outside until the tibial liner 12 is disengaged from the tibial tray 11) between the tibial liner 12 provided with the first side clamping position 125 and the second side clamping position 126 and the tibial tray 11 provided with the first side groove 114 and the second side groove 115 is 1.7 - 2.3 times that of the traditional tibial liner 12 and tibial tray 11. The locking force from outside to inside (referring to the force of pushing the tibial liner 12 from outside to inside until the tibial liner 12 is disengaged from the tibial tray 11) between the tibial liner 12 provided with the first side clamping position 125 and the second side clamping position 126 and the tibial tray 11 provided with the first side groove 114 and the second side groove 115 is 1.8 - 2.4 times that of the traditional tibial liner 12 and tibial tray 11.

[0056] Further, referring to Figure 4, the first side groove 114 and the second side groove 115 are respectively communicated with both ends of the rear end card slot 113. The distance in the sagittal plane from the foremost end of the front end card slot 112 to the rearmost end of the rear end card slot 113 is the first length L1. Herein, the foremost end of the front end card slot 112 refers to the end of the front end card slot 112 closest to the human abdomen, and the rearmost end of the rear end card slot 113 refers to the end of the rear end card slot 113 closest to the human back. Further, the distance in the sagittal plane from the end of the first side groove 114 close to the front end card slot 112 to the rearmost end of the rear end card slot 113 is the second length L2. The ratio range of the second length L2 to the first length L1 is 0.01 - 0.7, preferably 0.35 - 0.45. Further, the distance in the sagittal plane from the end of the second side groove 115 close to the front end card slot 112 to the rearmost end of the rear end card slot 113 is the third length L3. The ratio range of the third length L3 to the first length L1 is 0.01 - 0.7, preferably 0.35 - 0.45. The distance in the sagittal plane from the end of the front end card slot 112 close to the first side groove 114 to the foremost end of the front end card slot 112 is the fourth length L4. The ratio range of the fourth length L4 to the first length L1 is 0.01 - 0.3; the distance in the sagittal plane from the end of the front end card slot 112 close to the second side groove 115 to the foremost end of the front end card slot 112 is the fifth length L5. The ratio range of the fifth length L5 to the first length L1 is 0.01 - 0.4.

[0057] Correspondingly, refer to Figure 8, the first side clamping position 125 and the second side clamping position 126 are respectively connected to both ends of the rear end clamping groove 113. The distance in the sagittal plane from the foremost end of the front end clamping position 123 to the rearmost end of the rear end clamping position 124 is the sixth length L6. Herein, the foremost end of the front end clamping position 123 refers to the end closest to the human abdomen of the front end clamping position 123, and the rearmost end of the rear end clamping position 124 refers to the end closest to the human back of the rear end clamping position 124. Further, the distance in the sagittal plane from the end of the first side clamping position 125 close to the front end clamping position 123 to the rearmost end of the rear end clamping groove 113 is the seventh length L7. The ratio range of the seventh length L7 to the sixth length L6 is 0.01 - 0.9; preferably 0.35 - 0.45. The distance in the sagittal plane from the end of the second side clamping position 126 close to the front end clamping position 123 to the rearmost end of the rear end clamping position 124 is the eighth length L8. The ratio range of the eighth length L8 to the sixth length L6 is 0.01 - 0.7, preferably 0.35 - 0.45. The distance in the sagittal plane from the end of the front end clamping position 123 close to the first side clamping position 125 to the foremost end of the front end clamping position 123 is the ninth length L9. The ratio range of the ninth length L9 to the sixth length L6 is 0.01 - 0.9. The distance in the sagittal plane from the end of the front end clamping position 123 close to the second side clamping position 126 to the foremost end of the front end clamping position 123 is the tenth length L10. The ratio range of the tenth length L10 to the sixth length L6 is 0.01 - 0.4. Preferably, only part of the clamping positions within the range of the ninth length L9 are provided with flanges for locking with the clamping grooves within the range of L4 of the tibial tray, and the rest are locked with the groove wall of the tibial tray by their contour shapes, or no flanges are provided and they are only locked with the groove wall of the tibial tray by their contour shapes. This can reduce the interference amount, reduce the force required during the installation process, and facilitate the operation.

[0058] Further, in the traditional tibial prosthesis, a locking structure of a clamping groove and a clamping position is not provided on the inner and outer sides, because in the traditional concept, it is considered that opening clamping grooves on the inner and outer sides of the tibial tray 11 and respectively providing clamping positions on the inner and outer sides of the tibial tray 11 will hinder the locking between the tibial liner 12 and the tibial tray 11, and even cause the installation portion 122 of the tibial liner 12 to be unable to be inserted into the receiving groove 111 of the tibial tray 11. And when the lengths of the first clamping groove, the second clamping groove, the first clamping position, and the second clamping position are too short, the clamping effect is not obvious. When the lengths of the first clamping groove, the second clamping groove, the first clamping position, and the second clamping position are too long, it is easy to hinder the tibial liner 12 from being inserted into the tibial tray 11 prosthesis. However, the present application eliminates the above technical prejudice by designing the lengths of the first clamping groove, the second clamping groove, the first clamping position, and the second clamping position, which not only ensures that the tibial liner 12 can be easily inserted into the tibial tray 11 prosthesis, but also significantly improves the locking strength between the tibial liner 12 and the tibial tray 11 prosthesis, especially improving the ability of the unicompartment tibial prosthesis 10 to resist shear forces in the inner and outer directions.

[0059] Further, refer to Figure 4, the groove wall of the first side groove 114 is provided with a first straight surface 1141, the first straight surface 1141 is parallel to the sagittal plane, the groove wall of the second side groove 115 is provided with a second straight surface 1151, and the second straight surface 1151 is parallel to the sagittal plane. For the prosthesis itself, the first straight surface 1141 and the second straight surface 1151 being parallel is sufficient. Here, the "straight surface" means the part of the groove wall under the flange that is a plane parallel to the sagittal plane (i.e., Figure 4 the straight part in

[0060] . It should be known that the "straight surface" or "straight line" is not a straight surface or straight line in the mathematical sense, but a straight surface or straight line in the engineering sense, and a certain error range is allowed. Preferably, the length of the line segment formed by the intersection of the first straight surface 1141 and the horizontal plane is equal to or approximately equal to the second length L2. The ratio range of the length n of the line segment formed by the intersection of the second straight surface 1151 and the horizontal plane to the third length L3 is 0.01 - 0.8, preferably 0.3 - 0.45.

[0060] Correspondingly, referring to Figure 8 , the first side clamping position 125 is provided with a third straight surface 1251, the third straight surface 1251 is parallel to the sagittal plane, and the third straight surface 1251 is used for sliding cooperation with the first straight surface 1141. The second side clamping position 126 is provided with a fourth straight surface 1261, the fourth straight surface 1261 is parallel to the sagittal plane, and the fourth straight surface 1261 is used for sliding cooperation with the second straight surface 1151. For the prosthesis itself, the third straight surface 1251 and the fourth straight surface 1261 being parallel is sufficient. Here, the "straight surface" mentioned refers to the part of the side wall of the clamping position (i.e., the flange) that is a plane parallel to the sagittal plane (i.e., Figure 8 the straight part on

[0061] . Preferably, the length of the line segment formed by the intersection of the third straight surface 1251 and the horizontal plane is equal to or approximately equal to the seventh length L7. The ratio range of the length of the line segment formed by the intersection of the fourth straight surface 1261 and the horizontal plane to the eighth length L8 is 0.01 - 0.8, preferably 0.3 - 0.45.

[0061] Furthermore, during assembly, the rear end clamping position 124 of the tibial insert 12 is inserted into the rear end card slot 113 along the first straight surface 1141 and the second straight surface 1151, and then the front end of the tibial insert 12 is pressed so that the front end clamping position 123 of the tibial insert 12 is embedded into the front end card slot 112 of the tibial tray 11, thereby locking the tibial insert 12 and the tibial tray 11. Since the outer side of the traditional tibial insert 12 and the outer side assembly surface of the tibial tray 11 are curved surfaces, there is a risk of rotation during assembly. The unicondylar tibial prosthesis 10 of the present application, through the guiding action of the cooperation between the first straight surface 1141 and the third straight surface 1251, and the guiding action of the cooperation between the second straight surface 1151 and the fourth straight surface 1261, can make the tibial insert 12 be assembled into the tibial tray 11 along a direction parallel to the sagittal plane, avoiding the rotation problem during the assembly of the tibial insert 12 and the tibial tray 11.

[0062] Further, referring to Figure 10 , the tibial tray 11 is provided with a first upper end face 1181, a first lower end face 1182, a first outer end face 1184 and a first inner end face 1183. The tibial insert 12 is provided with a second upper end face 1281, a second lower end face 1282, a second outer end face 1284 and a second inner end face 1283. Among them, the distance H1 between the first upper end face 1181 and the second upper end face 1281 ranges from 0.01 mm to 0.2 mm. The distance H2 between the first lower end face 1182 and the second lower end face 1282 ranges from 0.01 mm to 0.2 mm. The distance H3 between the first inner end face 1183 and the second inner end face 1283 ranges from 0.01 mm to 0.2 mm. The distance H4 between the first outer end face 1184 and the second outer end face 1284 ranges from -0.1 mm to 0.1 mm, where a negative number indicates an interference fit between the tibial insert 12 and the tibial tray 11, and the interference fit ensures the stability of the tibial insert 12 after being assembled to the tibial tray 11. The value range of the above-mentioned mating spacing ensures the locking strength between the tibial prosthesis and the tibial insert 12, and improves the stability of the unicompartmental tibial prosthesis 10.

[0063] Further, referring to Figure 5 , the edge of the groove wall of the receiving groove 111 is provided with a first chamfer 1171 and a second chamfer 1172. Both the first chamfer 1171 and the second chamfer 1172 are provided on the side of the groove wall facing the tibial insert 12, that is, the upper side of the flange. And the extension range of the first chamfer 1171 corresponds to the extension range of the front card slot 112, and the extension range of the second chamfer 1172 corresponds to the extension range of the rear card slot 113, the extension range of the first side groove 114 and the extension range of the second side groove 115. Referring to Figure 9 , the front catch 123 is provided with a third chamfer 1271, and the third chamfer 1271 matches the first chamfer 1171. The rear catch 124, the first side catch 125 and the second side catch 126 are all provided with a fourth chamfer 1272, and the fourth chamfer 1272 matches the second chamfer 1172. By matching the third chamfer 1271 with the first chamfer 1171 and the fourth chamfer 1272 with the second chamfer 1172, the problem that the assembly force between the tibial insert 12 and the tibial tray 11 prosthesis is too large and difficult to assemble is solved, the failure rate of the unicompartmental tibial prosthesis 10 is reduced, and the service life of the unicompartmental tibial prosthesis 10 is improved. Preferably, the angle of the first chamfer 1171 is greater than or equal to the angle of the second chamfer 1172. Preferably, the angle of the first chamfer 1171 can be slightly larger than the angle of the second chamfer 1172, so that the tibial insert 12 is more easily assembled into the tibial tray 11.

[0064] Referring to Figure 11-13, this application also provides a unicondylar tibial prosthesis 20 of another embodiment. In this embodiment, the first straight surface 1141 and the second straight surface 1151 in the tibial tray 11 of the above-mentioned unicondylar tibial prosthesis 10 and the third straight surface 1251 and the fourth straight surface 1261 in the tibial insert 12 are changed to inclined surfaces. Specifically, a unicondylar tibial prosthesis 20 in one embodiment includes a tibial tray 21 and a tibial insert 22. The groove wall of the first side groove of the tibial tray 21 is provided with a first inclined surface 2141, and the first inclined surface 2141 is arranged at an acute angle with the bottom wall of the receiving groove 211. The groove wall of the second side groove is provided with a second inclined surface 2151, and the second inclined surface 2151 is arranged at an acute angle with the bottom wall of the receiving groove 211. The end surface of the mounting portion close to the bottom wall of the receiving groove 211 is the first end surface 227. The first side clamping position is provided with a third inclined surface 2251, and the third inclined surface 2251 is arranged at an acute angle with the first end surface 227, and the third inclined surface 2251 is used for sliding cooperation with the first inclined surface 2141. The second side clamping position is provided with a fourth inclined surface 2261, and the fourth inclined surface 2261 is arranged at an acute angle with the first end surface 227, and the fourth inclined surface 2261 is used for sliding cooperation with the second inclined surface 2151. Preferably, the included angle A1 between the first inclined surface 2141 and the bottom wall of the receiving groove 211 ranges from 30° to 85°, preferably 50° to 75°; the ratio of the length of the line segment formed by the intersection of the second inclined surface 2151 and the horizontal plane to the third length L3 ranges from 0.01 to 0.8. The included angle A2 between the second inclined surface 2141 and the bottom wall of the receiving groove 211 ranges from 30° to 85°, preferably 50° to 75°; the included angle B1 between the third inclined surface 2251 and the first end surface 227 ranges from 30° to 85°, preferably 50° to 75°; the ratio of the length of the line segment formed by the intersection of the fourth inclined surface 2261 and the horizontal plane to the seventh length L7 ranges from 0.01 to 0.8. The included angle B2 between the fourth inclined surface 2261 and the first end surface 227 ranges from 30° to 85°, preferably 50° to 75°. When the included angle between the inclined surface and the first end surface 227 is within the above range, the installation of the tibial tray and the tibial insert is more convenient, and the locking is also more firm. By changing the straight surfaces on the tibial insert 12 and the tibial tray 11 to inclined surfaces, the assembly guiding property of the tibial insert 22 and the tibial tray 21 can be improved, so that the tibial insert 22 can be inserted into the tibial tray 21 more smoothly, and the assembly hindrance caused by the first side groove and the second side groove can be reduced. It should be noted that the other structures of the unicondylar tibial prosthesis 20 are the same as those of the unicondylar tibial prosthesis 10 in the previous embodiment, and will not be elaborated here.

[0065] Further, referring to Figure 14-15, the present application also provides a unicondylar tibial prosthesis 30 of another embodiment. The unicondylar tibial prosthesis 30 includes a tibial tray 31 and a tibial insert 32. The tibial tray 31 is provided with a receiving groove 311 and a groove wall surrounding the receiving groove 311, and there is a notch in the groove wall, so that the groove wall is discontinuous. Preferably, there are notches between the front end card slot, the rear end card slot, the first side slot and the second side slot in pairs, making the four independent of each other. Specifically, refer to Figure 15 , the tibial tray 11 is provided with a first notch 312, and the first notch 312 is located between the groove wall of the first side slot 314 and the groove wall of the rear end card slot. Further, the tibial tray 11 is also provided with a second notch 313, and the second notch 313 is located between the groove wall of the front end card slot and the groove wall of the first side slot 314. In addition, there are another 2 notches respectively located between the groove wall of the rear end card slot and the groove wall of the second side slot 315 and between the groove wall of the front end card slot and the groove wall of the second side slot 315. By providing notches on the tibial tray 31, the problem that the assembly force between the tibial insert 32 and the tibial tray 31 is too large and difficult to assemble is solved, the failure rate of the tibial insert 32 is reduced, and the service life of the tibial insert 32 is improved. It should be noted that the other structures of the unicondylar tibial prosthesis 30 in this embodiment are the same as those of the unicondylar tibial prosthesis 10 or the unicondylar tibial prosthesis 20 in the foregoing embodiments, and will not be elaborated here.

[0066] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0067] The above-described embodiments only represent several implementation manners of the present invention. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. A unicondylar tibial prosthesis, characterized in that, comprising: a tibial tray, the tibial tray is provided with a receiving groove, the groove wall of the receiving groove is provided with opposite front end card slots and rear end card slots, and the groove wall of the receiving groove is also provided with opposite first side grooves and second side grooves; and, a tibial liner, the tibial liner includes a body and a mounting portion protruding outward from the body, the mounting portion is used for being embedded in the receiving groove, the mounting portion is provided with opposite front end positions and rear end positions, the mounting portion is also provided with opposite first side positions and second side positions, the front end position is used for being embedded in the front end card slot, the rear end position is used for being embedded in the rear end card slot, the first side position is used for being embedded in the first side groove, and the second side position is used for being embedded in the second side groove; the first side groove and the second side groove are respectively communicated with two ends of the rear end card slot, the distance in the sagittal plane from the foremost end of the front end card slot to the rearmost end of the rear end card slot is a first length, the distance in the sagittal plane from the end of the first side groove close to the front end card slot to the rearmost end of the rear end card slot is a second length, and the ratio range of the second length to the first length is 0.35 - 0.45; the distance in the sagittal plane from the end of the second side groove close to the front end card slot to the rearmost end of the rear end card slot is a third length, and the ratio range of the third length to the first length is 0.35 - 0.45; the first side position and the second side position are respectively connected to two ends of the rear end position, the distance in the sagittal plane from the foremost end of the front end position to the rearmost end of the rear end position is a sixth length, the distance in the sagittal plane from the end of the first side position close to the front end position to the rearmost end of the rear end position is a seventh length, and the ratio range of the seventh length to the sixth length is 0.35 - 0.45; the distance in the sagittal plane from the end of the second side position close to the front end position to the rearmost end of the rear end position is an eighth length, and the ratio range of the eighth length to the sixth length is 0.35 - 0.45; the distance in the sagittal plane from the end of the front end card slot close to the first side groove to the foremost end of the front end card slot is a fourth length, and the ratio range of the fourth length to the first length is 0.01 - 0.3; the distance in the sagittal plane from the end of the front end card slot close to the second side groove to the foremost end of the front end card slot is a fifth length, and the ratio range of the fifth length to the first length is 0.01 - 0.4; the distance in the sagittal plane from the end of the front end position close to the first side position to the foremost end of the front end position is a ninth length, and the ratio range of the ninth length to the sixth length is 0.01 - 0.9; the distance in the sagittal plane from the end of the front end position close to the second side position to the foremost end of the front end position is a tenth length, and the ratio range of the tenth length to the sixth length is 0.01 - 0.

4.

2. The unicondylar tibial prosthesis according to claim 1, characterized in that: The groove wall of the first side groove is provided with a first straight surface, the groove wall of the second side groove is provided with a second straight surface, and the first straight surface is parallel to the second straight surface; The first side clamping position is provided with a third straight surface for sliding cooperation with the first straight surface, the second side clamping position is provided with a fourth straight surface for sliding cooperation with the second straight surface.

3. The unicondylar tibial prosthesis according to claim 2, wherein, The ratio range of the length of the line segment formed by the intersection of the second straight surface and the horizontal plane to the third length is 0.01 - 0.8; the ratio range of the length of the line segment formed by the intersection of the second straight surface and the horizontal plane to the eighth length is 0.01 - 0.

8.

4. The unicondylar tibial prosthesis according to claim 1, wherein, The groove wall of the first side groove is provided with a first inclined surface, the first inclined surface is arranged at an acute angle with the bottom wall of the accommodation groove, the groove wall of the second side groove is provided with a second inclined surface, and the second inclined surface is arranged at an acute angle with the bottom wall of the accommodation groove; The end face of the installation part close to the bottom wall of the accommodation groove is the first end face, the first side clamping position is provided with a third inclined surface, the third inclined surface is arranged at an acute angle with the first end face, and the third inclined surface is used for sliding cooperation with the first inclined surface, the second side clamping position is provided with a fourth inclined surface, the fourth inclined surface is arranged at an acute angle with the first end face, and the fourth inclined surface is used for sliding cooperation with the second inclined surface.

5. The unicondylar tibial prosthesis according to claim 4, wherein, The included angle range between the first inclined surface and the bottom wall of the accommodation groove is 30° - 85°; the ratio range of the length of the line segment formed by the intersection of the second inclined surface and the horizontal plane to the third length is 0.01 - 0.8, the included angle range between the second inclined surface and the bottom wall of the accommodation groove is 30° - 85°; the included angle range between the third inclined surface and the first end face is 30° - 85°; the ratio range of the length of the line segment formed by the intersection of the fourth inclined surface and the horizontal plane to the seventh length is 0.01 - 0.8, the included angle range between the fourth inclined surface and the first end face is 30° - 85°.

6. The unicondylar tibial prosthesis according to claim 1, wherein, The edge of the groove wall of the accommodation groove is provided with a first chamfer and a second chamfer, and the extension range of the first chamfer corresponds to the extension range of the front end clamping groove, the extension range of the second chamfer corresponds to the extension range of the rear end clamping groove, the extension range of the first side groove, and the extension range of the second side groove; the front end clamping position is provided with a third chamfer, the third chamfer matches the first chamfer, and the rear end clamping position, the first side clamping position, and the second side clamping position are all provided with a fourth chamfer, and the fourth chamfer matches the second chamfer.

7. The unicondylar tibial prosthesis according to claim 6, wherein, The angle of the first chamfer is greater than or equal to the angle of the second chamfer.

8. The unicondylar tibial prosthesis according to any one of claims 1 - 7, wherein, The groove wall of the tibial tray is provided with a notch.

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