CN217525514U

CN217525514U - Locking osseointegration screw for cylindrical surface-associated osseointegration of artificial implant

Info

Publication number: CN217525514U
Application number: CN202123081239.0U
Authority: CN
Inventors: 王金成; 雒文彬; 赵昕
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2021-12-09
Filing date: 2021-12-09
Publication date: 2022-10-04
Anticipated expiration: 2031-12-09

Abstract

The utility model relates to a locking osseointegration screw for the cylindrical surface joint osseointegration of an artificial implant, which is used for carrying out the cylindrical surface joint osseointegration of the artificial implant and a host bone, and specifically comprises a screw head part, a screw neck part, a threaded rod main body and a screw tip part which are connected in sequence, wherein the shapes of the screw head part and the screw neck part are both cylinders, and the whole threaded surface of the threaded rod main body is covered with a microporous structure; the side surface of the screw head part is provided with a locking thread matched with the locking hole thread, and the center of the top surface of the screw head part is provided with a groove matched with a screw fixing wrench; the threaded rod main body comprises a first cylindrical threaded body, a second tapered threaded body and a third cylindrical threaded body which are integrally formed in the direction from the head of the screw to the tip of the screw. The utility model provides a locking osseointegration screw can strengthen the whole effect of osseointegration between artificial implant and host bone, realizes artificial implant's short-term mechanical fixation and long-term osseointegration effect.

Description

Locking osseointegration screw for cylindrical surface-associated osseointegration of artificial implant

Technical Field

The utility model belongs to the technical field of medical equipment, a locking and long-term osseointegration fixed orthopedics internal fixation device that can realize orthopedics artificial implant is related to a locking osseointegration screw that is used for artificial implant's cylinder to unite osseointegration is related to.

Background

Orthopaedic prosthetic implants rely on bone screws to mechanically fix the implant to the bone (as shown in fig. 1-3) for initial stabilization. Initial stabilization facilitates the growing together of the artificial implant with the bone, i.e. osseointegration. Long-term stability can only be achieved if the artificial implant is osteointegrated with the host bone.

Bone screws are commonly used for stabilization, fixation, fusion of human bones and for fixation between human bones and orthopedic implants. In the orthopedic joint replacement operation, especially the sacrum and pubis prosthesis fixation in the half pelvis replacement operation and the acetabular cup fixation in the primary and revision replacement of the hip joint, because the stress condition of screws is complex and the long-term osseointegration fixing capability is lacked, the prosthesis fixation failure can be caused by the phenomena of screw loosening, screw withdrawal and the like after the prosthesis screw fixation of partial patients, and the long-term prognosis is influenced. The screw material made of other biocompatible materials except metal is often inferior to the metal material in mechanical property, so that although part of the screw material achieves the bone growth effect, the phenomena of nail body breakage, screw absorption and the like can occur in long-term follow-up, and the screw material is not suitable for pseudo-intracorporeal plants needing long-term strong fixation.

Meanwhile, osseointegration of conventional orthopedic artificial implants is achieved by contacting a certain part of the artificial implant with a bone, mechanically fixing the artificial implant with a bone screw for stabilization, and then osseointegration, i.e., integration between the surface of the artificial implant and the surface of the host bone, such as integration between the surface of an acetabular bone-filing and the surface of an artificial acetabular prosthesis, integration between an artificial femoral stem and the inner wall of a medullary cavity, and the like. In such facet-to-facet osseointegration, bone screws are used only for mechanical fixation. If the face of the artificial implant is not integrated with the facial bone of the host bone, long-term stress stimulation may cause the screw to loosen and even break, resulting in failure of the artificial implant.

SUMMERY OF THE UTILITY MODEL

In order to overcome the problem that long-term osseointegration effect is not good, the bone screw is easy to become flexible or even break between the bone screw and the host bone that exist when the artificial implant is fixed in the prior art, the utility model provides a locking osseointegration screw for the integration of the cylinder combination bone of the artificial implant.

In order to achieve the purpose, the utility model adopts the following technical proposal:

a locking osseointegration screw for cylindrical surface joint osseointegration of an artificial implant, the locking osseointegration screw is used for cylindrical surface joint osseointegration of the artificial implant and a host bone, the artificial implant is provided with a locking hole in threaded fit with the locking osseointegration screw, the locking osseointegration screw comprises a screw head part, a screw neck part, a threaded rod main body and a screw tip part which are sequentially connected, the screw head part and the screw neck part are both cylindrical in shape, and the whole threaded surface of the threaded rod main body is covered with a microporous structure;

the side surface of the head of the screw is provided with a locking thread matched with the locking hole thread, and the center of the top surface of the head of the screw is provided with a groove matched with a screw fixing wrench;

the threaded rod main body comprises a first cylindrical threaded body, a second cylindrical threaded body and a third cylindrical threaded body which are integrally formed along the direction from the head part of the screw to the tip part of the screw, the maximum diameter of the second cylindrical threaded body is the same as the diameter of the first cylindrical threaded body, the diameter of the first cylindrical threaded body is the same as the diameter of the neck part of the screw, the minimum diameter of the second cylindrical threaded body is the same as the diameter of the third cylindrical threaded body, the thread depth of the first cylindrical threaded body is larger than the thread depth of the third cylindrical threaded body, the thread pitch of the first cylindrical threaded body is smaller than the thread pitch of the third cylindrical threaded body, and the thread depth and the thread pitch of the second cylindrical threaded body are gradually changed from the thread depth and the thread pitch of the first cylindrical threaded body to the thread depth and the thread pitch of the third cylindrical threaded body.

Compared with the prior art, the utility model discloses following beneficial effect has:

(1) The utility model provides a locking osseointegration screw for the integration of the cylinder combination osseointegration of artificial implant fixes the locking osseointegration screw with good osseointegration performance and nail body strength and the locking hole of the artificial implant into a whole on the basis of the integration of the face and the face bone, becomes the 'column' of the artificial implant, then screws the column with screw thread into the host bone, and enhances the integral effect of osseointegration through the integration of the column and the host bone, thereby realizing the short-term mechanical fixation and the long-term osseointegration effect of the artificial implant;

(2) Meanwhile, when a large number of bone defects exist below the prosthesis or the surface morphology of the prosthesis is poorly matched with the surface morphology of the host bone, the locking osseointegration screw can fix the prosthesis and the host bone through the osseointegration function of the locking osseointegration screw and the prosthesis. At the moment, the locking osseointegration screw independently plays a role of a 'column', so that the locking osseointegration screw serves as an 'inner support' between the prosthesis and a host bone, and the stable fixation of the prosthesis is realized.

Drawings

FIG. 1 is a CT view of a prior art fixation of an acetabular cup prosthesis using bone screws;

FIG. 2 is a CT view of a prior art fixation of an acetabular cup prosthesis using bone screws;

FIG. 3 is a CT view of a prior art fixation of a prosthesis for iliac and pubic portions using bone screws;

fig. 4 is a cross-sectional view of a locking osseointegration screw of the present invention.

Detailed Description

The technical solution of the present invention will be described in detail with reference to the accompanying drawings and preferred embodiments.

The utility model discloses a locking osseointegration screw that is used for artificial implant's cylinder to unite osseointegration, this locking osseointegration screw is used for carrying out cylinder with artificial implant and host bone and unites osseointegration. Specifically, the artificial implant is provided with a locking hole in threaded fit with the locking osseointegration screw, after the artificial implant is aligned with the host bone, the locking osseointegration screw fixes the artificial implant and the host bone through the locking hole, and the locking osseointegration screw is further connected with the host bone through an osseointegration structure designed by the locking osseointegration screw, so that the osseointegration between the artificial implant and the host bone is finally realized.

The utility model provides a locking osseointegration screw that is used for artificial implant's cylinder to unite osseointegration both has been applicable to the condition that false body and host bone surface morphology match, also be applicable to there being a large amount of defective bones or false body and the bad condition of host bone surface morphology matching in false body below, when false body and host bone surface morphology match, when the false body face on the artificial implant matches with the bone face of host bone, the false body face closely laminates through the pressure with the bone face, realize the osseointegration of face and face, then on the basis of face and face osseointegration, it is fixed as an organic whole with artificial implant's locking hole to have the locking osseointegration screw that osseointegration performance and nail body intensity are good, become this artificial implant's "post", then will take during the threaded post twists the host bone, integrate through post and host bone, the whole effect of osseointegration has been strengthened, thereby realize the short-term mechanical fixation and the long-term osseointegration effect of artificial implant. When a large number of bone defects exist below the prosthesis or the surface morphology of the prosthesis is poorly matched with the surface morphology of the host bone, the locking osseointegration screw can realize the fixation of the prosthesis and the host bone through the osseointegration function of the locking osseointegration screw and the locking function of the prosthesis. At the moment, the locking osseointegration screw solely plays the function of a 'column', thereby acting as an 'inner support' between the prosthesis and the host bone and realizing the stable fixation of the prosthesis.

The utility model provides a can realize locking and long-term osseointegration fixed orthopedics internal fixation screw-the structural design of locking osseointegration screw of orthopedics metal prosthesis (artificial implant) through locking nut, osseointegration structural design and surperficial microporous structure, as shown in fig. 4, locking osseointegration screw is including the screwhead 1 that connects gradually, screw neck 2, threaded rod main part 3 and screw point portion 4, wherein screwhead 1 and screw neck 2's shape is the cylinder, and the whole screw surface of threaded rod main part 3 covers there is microporous structure, in order to do benefit to the bony bone growth to go into, improve long-term fixed effect.

Specifically, the side of the screw head 1 is provided with a locking thread 1-1 matched with the locking hole, and the center of the top surface of the screw head 1 is provided with a groove 1-2, such as an inner hexagonal groove, for matching with a screw fixing wrench, such as an inner hexagonal wrench, and the like, so that the screw can be conveniently screwed into the host bone.

The threaded rod main body 3 is divided into three parts, namely a first cylindrical thread body 3-1, a second conical thread body 3-2 and a third cylindrical thread body 3-3, the first cylindrical thread body 3-1, the second conical thread body 3-2 and the third cylindrical thread body 3-3 are integrally formed along the direction from the screw head part 1 to the screw tip part 4, the thread depth of the first cylindrical thread body 3-1, the second conical thread body 3-2 and the third cylindrical thread body 3-3 is gradually reduced, the thread pitch is gradually increased, and the thread width is gradually increased. Still referring to fig. 4, the first cylindrical screw body 3-1 and the third cylindrical screw body 3-3 each have a constant thread depth, pitch, and thread width, and the second tapered screw body 3-2 has a variable pitch thread. The maximum diameter of the second conical thread body 3-2 is the same as the diameter of the first cylindrical thread body 3-1, and the diameter of the first cylindrical thread body 3-1 is the same as the diameter of the screw neck 2; the minimum diameter of the second conical thread body 3-2 is the same as the diameter of the third cylindrical thread body 3-3; the thread depth of the first cylindrical screw body 3-1 is greater than the thread depth of the third cylindrical screw body 3-3, the thread pitch of the first cylindrical screw body 3-1 is less than the thread pitch of the third cylindrical screw body 3-3, and the thread depth and the thread pitch of the second conical screw body 3-2 are gradually changed from the thread depth and the thread pitch of the first cylindrical screw body 3-1 to the thread depth and the thread pitch of the third cylindrical screw body 3-3. The overall depth change of the threads of the threaded rod body 3 ensures that the inner diameter of the nail body is unchanged so as to reduce stress concentration and improve mechanical strength.

The utility model provides a locking osseointegration screw has following advantage:

(1) The threaded rod main body of the locking osseointegration screw adopts a stepped taper variable pitch design of a cylindrical threaded body, a tapered threaded body and a cylindrical threaded body, and through a small diameter coefficient and a shallow thread design near the tip of the screw, the locking osseointegration screw reduces stress concentration between the thread and a bone substance in the screwing-in process and the fixing process, so that damage to the bone substance and occurrence of osteolysis are reduced, tight combination between the surface of the screw and the bone substance is realized, the osseointegration effect is achieved, and the long-term fixing stability of the screw is improved;

(2) The design of the denser deep threads at the middle rear part of the threaded rod main body can improve the fixing strength between the screw and the bone, and realize the early strong fixation of the screw, thereby realizing the long-term osseointegration and improving the long-term fixing effect of the prosthesis;

(3) The locking screw thread on the side surface of the screw head is matched with the screw thread in the locking hole of the artificial implant prosthesis to realize the locking of the prosthesis and the screw, and the osseointegration effect of the prosthesis and the bone is finally realized through the osseointegration of the screw and the bone;

(4) The screw neck is of a non-thread cylindrical structure and is matched with the head of the screw, so that a cushion block or bone grafting can be arranged at the screw neck to improve the matching degree of the prosthesis and a host bone under the condition that the prosthesis and the bone structure cannot be completely matched; the locking osseointegration screw can be used for simultaneously fixing the prosthesis and two ends of sclerotin, so that the effect of an inner support of the prosthesis is realized, and the complex orthopedic joint replacement surgery is facilitated.

Further, the threaded rod body 3 is designed with a smooth groove in its threaded cross section.

Further, the threaded rod body 3 has a thread depth range of 0.5 to 2mm, a thread width range of 0.5 to 2mm, and a ratio of the thread width to the thread pitch range of 1.

Further, the maximum diameter range of the threaded rod body 3 is 3 to 10mm, and the minimum diameter range is 1.5 to 5mm.

Further, the overall length of the locking osseointegration screw is 20mm to 100mm, and the length of the screw neck 2 is 5mm to 20mm.

Further, the threaded rod body 3 has a smooth groove in the cross section of the thread.

Further, the utility model provides a titanium alloy material can be chooseed for use to the material of locking osseointegration screw to can adopt multiple technology to make, make its mechanical strength can satisfy clinical treatment requirement, the phenomenon of rupture is difficult for appearing.

In the clinic, for example, in the hip replacement operation, the acetabular cup is fixed, and the acetabular cup surface is firstly ground and filed to remove the surface cartilage, so that the subchondral bone is exposed, and then the cup corresponding to the model is pressed vertically to realize press fit, so that the subchondral bone is fully contacted and fixed with the surface coating of the cup, and the cup prosthesis is stable for a long time due to the growth of later-stage bone. If the initial stability of the acetabular cup is not ideal, the bottom of the acetabular cup needs to be screwed into screws in a safe area, and downward pressure is applied to the acetabular cup through the screws. The initial stability of the cup at this time is improved, but long term stability is still dependent on bone ingrowth between the cup surface and the acetabular bony mass. The acetabular cup prosthesis and the acetabular bone are still fixed in a surface-surface mode. Under the guidance of the concept of 'column-surface combined osseointegration', the locking osseointegration screw of the utility model can be used for realizing fixation of a mortar cup and an acetabular bone from three aspects: firstly, the contact pressure between the cup and the subchondral bone is increased by the downward pressure provided by the traditional screw, so that the initial stability of the cup prosthesis is improved; secondly, the osseointegration thread design of the main body part of the threaded rod and the micropore structure covered on the surface of the thread realize the osseointegration and bone ingrowth effect, and improve the long-term fixation stability of the screw and the pelvis sclerotin; thirdly, the nail body and the acetabulum prosthesis are mechanically locked through a locking structure at the head part of the screw. At the moment, the locking osseointegration screw realizes the plane-plane fixation by playing the functions of the traditional screw, and also serves as a connecting column between the acetabular cup prosthesis and acetabular sclerotin through the osseointegration and locking structure design, thereby realizing the concept of the column-plane combined osseointegration. Meanwhile, when a large number of bone defects exist below the prosthesis or the surface morphology of the prosthesis is poorly matched with the surface morphology of the host bone, the locking osseointegration screw can fix the prosthesis and the host bone through the osseointegration function of the locking osseointegration screw and the prosthesis. At the moment, the locking osseointegration screw independently plays a role of a column and serves as an inner support between the prosthesis and the host bone, so that the prosthesis and the host bone are fixed.

As another example, in a hemi-pelvic replacement procedure, a prosthesis of the iliac and pubic portions needs to be secured to the sacrum and contralateral ilia by screws, and with conventional screws, the full fixation strength of the prosthesis relies on the downward force exerted by the screws on the prosthesis to effect "face-to-face" fixation of the prosthesis to the bone. In a complex biomechanical environment after the prosthesis is implanted, nail pulling often occurs, so that the prosthesis fails, and the long-term follow-up effect is poor. Use the utility model discloses a locking osseointegration screw can realize the osseointegration of screw and sacrum and pubic bone through the osseointegration design and the surperficial microporous structure of locking osseointegration screw, on this basis, realizes the mechanical locking of false body and the nail body through locking structure. At the same time, the pressure fixation by locking the osseointegration screw further promotes bone ingrowth in the contact area of the prosthesis with the bone, thus improving initial and long-term stability.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent several embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A locking osseointegration screw for cylindrical joint osseointegration of an artificial implant characterized in that it is used for cylindrical joint osseointegration of an artificial implant with a host bone, the artificial implant is provided with a locking hole in threaded fit with the locking osseointegration screw, the locking osseointegration screw comprises a screw head (1), a screw neck (2), a threaded rod body (3) and a screw tip (4) which are connected in sequence, the screw head (1) and the screw neck (2) are both cylindrical in shape, and all the thread surfaces of the threaded rod body (3) are covered with a microporous structure;

the side surface of the screw head (1) is provided with a locking thread (1-1) matched with the locking hole in a threaded manner, and the center of the top surface of the screw head (1) is provided with a groove (1-2) matched with a screw fixing wrench;

the threaded rod main body (3) comprises a first cylindrical thread body (3-1), a second conical thread body (3-2) and a third cylindrical thread body (3-3) which are integrally formed in the direction from the screw head (1) to the screw tip (4), the maximum diameter of the second conical thread body (3-2) is the same as the diameter of the first cylindrical thread body (3-1), the diameter of the first cylindrical thread body (3-1) is the same as the diameter of the screw neck (2), the minimum diameter of the second conical thread body (3-2) is the same as the diameter of the third cylindrical thread body (3-3), the thread depth of the first cylindrical thread body (3-1) is greater than the thread depth of the third cylindrical thread body (3-3), the thread pitch of the first cylindrical thread body (3-1) is smaller than the thread pitch of the third cylindrical thread body (3-3), and the thread depth and the thread pitch of the second conical thread body (3-2) gradually change from the first cylindrical thread body (3-1) to the third cylindrical thread pitch (3-3).

2. The locking osseointegration screw for cylindrical joint osseointegration of an artificial implant according to claim 1, characterized in that the threaded shank body (3) has a thread depth ranging from 0.5 to 2mm, a thread width ranging from 0.5 to 2mm, and a ratio of thread width to thread pitch ranging from 1 to 2 to 1.

3. The locking osseointegration screw for cylindrical coupled osseointegration of an artificial implant according to claim 1, characterized in that the threaded shank body (3) has a maximum diameter in the range of 3-10 mm and a minimum diameter in the range of 1.5-5 mm.

4. The locking osseointegration screw for cylindrical coupled osseointegration of an artificial implant according to claim 1, characterized in that the overall length of the locking osseointegration screw is between 20mm and 100mm and the length of the screw neck (2) is between 5mm and 20mm.

5. The locking osseointegration screw for cylindrical joint osseointegration of an artificial implant according to claim 1, characterized in that the threaded cross section of the threaded shank body (3) is a smooth groove.

6. The locking osseointegration screw for cylindrical joint osseointegration of an artificial implant according to claim 1, characterized in that the shape of the groove (1-2) is hexagonal.

7. The locking osseointegration screw for cylindrical combined osseointegration of an artificial implant according to claim 1, characterized in that the material of the locking osseointegration screw is titanium alloy.