Background
At present, a treatment strategy aiming at acetabular defects in hip revision is mainly based on Paprosky typing, and the key point of treatment is to obtain stable fixation of a acetabular cup and residual acetabular bone again. Depending on the extent and location of acetabular defects, common acetabular reconstruction strategies include: the cup comprises a cup body. For extremely severe bone defects, there are also 3D printed semi-pelvic prostheses, etc. The purpose of the above various technologies is to restore the acetabulum structure close to the human body structure, which requires a very rich experience to select a proper operation strategy and has high requirements on operation technology.
The problems of the prior art for reconstructing acetabulum are as follows:
(1) the acetabulum reconstruction at the pelvis side has great difficulty and high technical requirements:
reconstruction of the acetabulum on the pelvic side, where the bone defect is severe, requires a large number of implants, such as autologous bone, allogeneic bone, bone cement or metal implants, to achieve a hemispherical surface with relative strength. Has extremely high requirements on the experience of operators and the operation technique, increases the infection risk and increases the operation cost.
(2) Poor stability of the reconstructed hip joint:
the size and direction of the acetabulum are limited under the influence of residual bone, and the acetabulum position after limited compromise often cannot provide enough stability; secondly, the reconstructed acetabulum is often large in size, even a jumbo cup is used, so that the diameter ratio of the ball to the acetabulum is overlarge, the movement range of the hip joint is limited, and the risk of dislocation caused by impact is relatively increased.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, it is an object of the present invention to provide a trans-hip prosthesis for severe acetabular defects that solves the problems of the prior art.
In order to achieve the above and other related objects, the present invention provides a trans-hip prosthesis, including a femur side prosthesis and an acetabulum side prosthesis, where the femur side prosthesis includes a femur cup and a femur handle, the femur cup and the femur handle are connected by a connecting neck, the acetabulum side prosthesis includes an acetabulum ball head and a bone body fitting part, the acetabulum ball head and the bone body fitting part are connected by a ball head support, and the femur cup and the acetabulum ball head are matched.
In some embodiments of the present invention, the surface of the bone body attaching part is a rough surface.
In some embodiments of the invention, the acetabular lateral prosthesis comprises a plurality of bone abutment portions, at least some of which are configured to abut one or more of an acetabular bone in an ischial branch direction, an acetabular bone in a pubic branch direction, or an acetabular bone in an iliac direction.
In some embodiments of the invention, the shaft engaging portion further comprises an engaging extension.
In some embodiments of the present invention, the bone body attaching part is provided with a through hole.
In some embodiments of the invention, the acetabular lateral prosthesis further comprises a pelvic fixation member, the pelvic fixation member cooperating with the through hole.
In some embodiments of the invention, the ball head support includes a central portion to which the acetabular ball head and each bone engaging portion are respectively connected.
In some embodiments of the invention, the angle of the shaft angle between the connecting neck and the femoral stem is 125-140 degrees, the distance between the center of the acetabulum ball head and the perpendicular line of the axis of the femoral stem is 30-40 mm, and the center of the femoral cup is positioned on the extension line of the connecting neck.
In some embodiments of the invention, a spacer is further provided in the femoral cup.
In some embodiments of the invention, when the trans-hip prosthesis is fitted to the corresponding human body part, the projection of the center of the acetabular ball head on the vertical axis does not fall outside the femoral cup in flexion of 110-120 °, in abduction of 45 ° to adduction of 15 °, in thigh internal rotation of 30 ° to external rotation of 30 ° in flexion of 90 °, and in extension of hip external rotation to 90 °.
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.
Please refer to fig. 1 to 6. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of the components in actual implementation may be changed at will, and the layout of the components may be more complex.
Referring to fig. 1 to 5, the invention provides a trans-hip prosthesis, which comprises a femoral side prosthesis 1 and an acetabular side prosthesis 2, wherein the femoral side prosthesis 1 comprises a femoral cup 11 and a femoral stem 12, the femoral cup 11 and the femoral stem 12 are connected through a connecting neck 13, the acetabular side prosthesis 2 comprises an acetabular ball head 21 and a bone body fitting part 22, the acetabular ball head 21 and the bone body fitting part 22 are connected through a ball head support 23, and the femoral cup 11 and the acetabular ball head 21 are matched. As shown in fig. 6, the trans-hip prosthesis provided by the invention can be tightly connected with the acetabulum of a human body through a bone body fitting part 22, the femoral cup 11 and the acetabulum ball head 21 can be matched, and the femoral stem 12 is usually matched with the medullary cavity of the femur of the human body.
The trans-hip joint prosthesis provided by the invention can comprise a femur side prosthesis 1, and the femur side prosthesis 1 is integrally used for being matched and installed with a human femoral medullary cavity. The femoral side prosthesis 1 can be produced individually through a 3D printing technology, so that the femoral side prosthesis can be better matched with human femoral medullary cavities of different patients and the like, and the fit at a proper angle among all the parts can be met.
The femoral side prosthesis 1 may include a femoral stem 12. The femoral stem 12 is generally intended to cooperate with the medullary cavity of the human femur and serves primarily to fixedly support the femoral cup 11. The femoral stem 12 generally has a rounded outer surface with a suitable cross-sectional shape to ensure that the femoral stem 12 has a suitable fit with the medullary cavity. For example, the femoral stem 12 may be a frustum with a taper, and the cross section thereof may be an ellipse, and the like.
The femoral prosthesis 1 may include a connecting neck 13. The angle of connection between the connecting neck 13 and the femoral cup 11 and the femoral stem 12, and its length itself, is largely dependent on the position of the femoral cup 11 relative to the femoral stem 12. Generally, the connecting neck 13 has a rounded outer surface and a suitable cross-sectional shape to ensure that the angle of the femoral cup is constant and does not change during movement. For example, the connecting neck 13 may be a cylinder, a truncated cone with a certain taper, or the like, and the cross section thereof may be an ellipse or the like.
The femoral prosthesis 1 may include a femoral cup 11. The femoral cup 11 may be generally connected to and may form an integral part of a hip replacement, which is a reverse-mount prosthetic cup, connected to the femoral stem 12 by the neck 13, as compared to a conventional hip replacement. The orientation of the femoral cup 11 corresponds to the orientation of the acetabular ball head 21 and is required to meet the constraint of no dislocation over a range of angles of rotation for normal human movement to the greatest extent possible. Generally, the anteversion angle of the femoral cup 11 needs to be matched to the femoral anteversion angle to improve hip joint stability and to avoid misalignment between the acetabular ball head 21 and the femoral cup 11 when the subject receives external forces (e.g., impact during exercise). For example, the angle of the shaft neck angle between the connecting neck 13 and the femoral stem 12 may be 125-140 °, 125-130 °, 130-135 °, or 135-140 °. For another example, the distance between the center of the acetabulum ball head 21 and the perpendicular line of the axis of the femoral stem 12 may be 30-40 mm, 30-32 mm, 32-34 mm, 34-36 mm, 36-38 mm, or 38-40 mm. As another example, the center of the femoral cup 11 is generally located on the extension of the connective neck 13. For example, when the trans-hip prosthesis is fitted to a corresponding part of a human body, under the conditions of 110 to 120 degrees of flexion (an angle formed by a thigh and a vertical axis when the affected thigh is bent along a sagittal plane to be close to the chest in a normal lying state of the human body), 45 degrees of abduction to 15 degrees of adduction (an angle formed by a thigh and a vertical axis when the affected thigh is rotated on a coronal plane to the outer side and the inner side of the human body, respectively in a normal lying state of the human body), 30 degrees of internal rotation to 30 degrees of external rotation (an angle formed by a calf on the affected side rotated along the coronal plane to the outer side and the inner side of the human body and a vertical axis when the affected calf is rotated along the coronal plane in a normal sitting posture) when the hip is flexed 90 degrees, and when the hip is extended to 90 degrees (an angle formed by a calf on the sagittal axis when the affected calf is rotated along the horizontal plane to the inner side of the human body in a normal prone state), the projection of the center of the acetabular ball head 21 in the direction of the (human) vertical axis does not fall outside the femoral cup 11.
In the above-mentioned femoral prosthesis 1, the femoral cup 11 may further include a spacer 14. The spacer 14 is primarily used to cushion the acetabular ball 21 and the cup of the femoral cup 11 to improve the fit between the two. The gasket 14 may be made of a polymer polyethylene material, a ceramic material, or the like.
In the femoral prosthesis 1, the components of the femoral prosthesis 1 can be assembled in a suitable manner, so as to facilitate preparation, carrying and the like. For example, the femoral cup 11 and the connecting neck 13 may be in an interference fit, a sleeve fit, or the like, or may be in a press fit connection, so as to achieve locking in all directions.
The trans-hip joint prosthesis provided by the invention can comprise an acetabulum side prosthesis 2, and the acetabulum side prosthesis 2 is integrally used for being matched and installed with serious acetabular defects. The acetabulum side prosthesis 2 can be produced individually through a 3D printing technology, so that the acetabulum side prosthesis can be better matched with defective acetabulums of different patients, and can meet the angle matching with a femoral cup 11.
The acetabular lateral prosthesis 2 may include an acetabular ball head 21. The acetabular ball head 21 may be generally spherical in shape to fit the femoral cup 11. In the invention, the installation position of the acetabulum ball head 21 is opposite to the position of the traditional ball head, and the reverse matching of the acetabulum ball head 21 and the femoral cup 11 is mainly realized.
The acetabulum-side prosthesis 2 may include a bone body attaching part 22, and the bone body attaching part 22 may be mainly used as a base of the acetabulum-side prosthesis 2 and is used for being in force fit connection with a severely defected acetabulum. The mating surface of the shaft engaging portion 22 is generally a rough surface that is generally shaped to mate with the acetabulum to ensure a tight fit therebetween. Bone engaging portion 22 is generally configured to engage a good bony portion of the subject for purchase attachment, for example, at least a portion of bone engaging portion 22 may be configured to engage a bony prominence, and in particular may engage an acetabular bone in the ischial branch direction, an acetabular bone in the pubic branch direction, or a combination of one or more of acetabular bones in the iliac direction. Generally speaking, the bone engaging portion 22 may be provided with suitable structure to facilitate connection of the bone engaging portion 22 to the acetabulum. For example, the bone engaging portion 22 may include a through hole, and the acetabular component 2 may further include a pelvic fastener 24 (e.g., a set screw, etc.), the pelvic fastener 24 generally cooperating with the through hole to attach the bone engaging portion 22 to the acetabulum. For another example, the bone engaging portion 22 may further include an engaging extension 221, and the engaging extension 221 may further enlarge the engaging area between the bone engaging portion 22 and the acetabulum to reinforce the connection. The apposition extension 221 may be formed integrally with the shaft apposition portion 22.
The acetabular lateral prosthesis 2 may include a ball head support 23, and the ball head support 23 is primarily used to connect the force-receiving locations (e.g., the acetabular ball head 21 and the bone body abutment 22) in the acetabular lateral prosthesis 2 to form a suitable support. For example, the ball head support 23 may include a central portion 231, the central portion 231 may be the intersection of the connection between the acetabular ball head 21 and each of the body engaging portions 22, the body engaging portions 22 may be connected to the central portion 231 to provide the ball head support 23 with a suitable force receiving location, the acetabular ball head 21 may be connected to the central portion 231 for mating with the acetabular ball head 21, and the relative position of the ball head support 23 as a whole may be adjusted depending on the angular relationship of the connection between the acetabular ball head 21 and the central portion 231 to the femoral cup 11. Each portion of the ball bearing 23 generally has a rounded outer surface, for example, the central portion 231 may be spherical, and the connection between the acetabular ball head 21 and/or bone body engaging portion 22 and the central portion 231 may be a cylinder, a truncated cone with a constant taper, or the like, which may be circular or elliptical in cross-section.
In the above-mentioned acetabulum side prosthesis 2, the components of the acetabulum side prosthesis 2 can be assembled in a proper manner, so as to be convenient for preparation, carrying and the like. For example, there may be an interference connection or socket between the acetabular ball 21 and the ball support 23 to achieve locking in all degrees of freedom.
When a patient with serious acetabulum defect undergoes total hip replacement or revision surgery, the bone retention state of the acetabulum cannot meet the placement requirement of a acetabular cup prosthesis, the acetabulum can be used for placing the acetabular cup under poor conditions, and the final surgical effect is difficult to achieve. The trans-hip prosthesis provided by the invention is used for helping a subject to achieve the best operation effect. In addition, according to the trans-hip prosthesis provided by the invention, the position of the femoral cup is confirmed by a determined position which ensures that the acetabular ball head does not fall off in the normal posture of the hip joint, so that the position of the femoral cup is unique, and the femoral cup and the femoral stem can be produced in batch by the traditional metal processing technology and become standard components with different sizes and models for selective use. The acetabular ball head in the acetabular side prosthesis usually corresponds to the femoral cup, and the rest parts can be produced individually by the subject, so that the only orientation of the acetabular ball head is ensured, and the forcible connection between the acetabular side prosthesis and the proper position of the acetabulum of the subject can be ensured. Overall, the trans-hip prosthesis provided by the invention can avoid various problems when a stable cup is reconstructed on the pelvis side with serious acetabular defect, so that the cup and ball head size more suitable for a patient can be obtained, the limitation of angles such as the anterior inclination angle and the abduction angle of the trans-hip is broken through, the degree of freedom is relatively higher, the operation difficulty and cost can be effectively reduced, the operation structure is improved, and the trans-hip prosthesis has a good industrialization prospect.
In conclusion, the present invention effectively overcomes various disadvantages of the prior art and has high industrial utilization value.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which may be accomplished by those skilled in the art without departing from the spirit and scope of the present invention as set forth in the appended claims.