CN211131550U

CN211131550U - Femoral implant

Info

Publication number: CN211131550U
Application number: CN201921259905.5U
Authority: CN
Inventors: 王彩梅; 周一新; 靳忠民
Original assignee: Beijing AK Medical Co Ltd
Current assignee: Beijing AK Medical Co Ltd
Priority date: 2019-08-05
Filing date: 2019-08-05
Publication date: 2020-07-31
Anticipated expiration: 2029-08-05

Abstract

The utility model provides a femoral implant, include: a pin securable in the femoral neck; a crown portion disposed at the first end of the pin, the crown portion capable of wrapping an end of the femoral neck. The technical scheme of the utility model patient's later stage has been solved effectively among the prior art and has need cut off the femoral head and implement hip joint replacement art, influences great problem to the patient.

Description

Femoral implant

Technical Field

The utility model relates to an artificial joint prosthesis field particularly, relates to a femoral implant.

Background

Articular cartilage damage is a common disease in orthopedics. In the field of orthopedic surgery, arthritis caused by traumatic and degenerative cartilage tissue injury due to diseases, wounds and the like is a problem in the medical field all over the world, and the cartilage tissue has no blood supply, and nutrition comes from moistening of peripheral joint synovial fluid, so that regeneration is difficult after injury. Traditional methods for treating cartilage damage include joint grinding, drilling, microfracture, and arthroscopic lavage, which fail to restore damaged cartilage and subchondral bone to their original normal tissue structures. The autologous tissue transplantation has better curative effect but limited material supply; foreign materials are relatively abundant in origin, but may cause immune rejection and risk of disease transmission. Currently, the development of tissue substitutes for damaged tissue using tissue engineering is currently in the laboratory research phase, and there is no more effective treatment available.

Thighbones are the most important bones of human bodies, the thighbones are more important, and the supporting function of the thighbones is relied on for the vertical walking, the movement and the labor of people. The femoral head is also the most vulnerable site. After the femoral head is diseased, sclerotin of a patient seriously breaks, trabecula disappears or most of the trabecula disappears, large-area saccular light transmission at multiple positions in the femoral head changes, multiple positions of sclerotic high-density sclerotin changes, the femoral head seriously collapses, deforms, is flat and large, and often causes hip joint pain, joint function limitation, walking lameness and other symptoms. If no effective treatment is performed in the early stage, the femoral head is finally cut off in the clinic and hip replacement surgery is performed in the late stage, so that early intervention plays an important role in retaining the femoral head and preventing rapid deterioration of the disease.

Long-term clinical practice has shown that Total Hip Arthroplasty (THA) is undoubtedly an effective and robust treatment for coxitis, especially in elderly patients, with a 10-year survival rate of the prosthesis exceeding 90%. However, for younger patients, especially male patients under 55 years old, total hip arthroplasty suffers from a more pronounced deficiency in long-term effects — a higher early revision rate with a 10-year prosthesis survival rate of 80% and 33% after 16 years.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a femoral implant to solve among the prior art patient's late stage and need cut off the femoral head and implement the total hip joint replacement art, influence great problem to the patient.

In order to achieve the above object, the present invention provides a femoral implant comprising: a pin securable in the femoral neck; a crown portion disposed at the first end of the pin, the crown portion capable of wrapping an end of the femoral neck.

Further, the coronal portion includes a porous structural layer configured to contact an end of the femoral neck and a contact layer disposed on an outer surface of the porous structural layer and configured to contact the acetabulum or the acetabular prosthesis.

Furthermore, the inner side surface of the porous structure layer comprises a cylindrical surface and a conical surface which are connected, the conical surface is gradually enlarged from the first end to the second end of the pin, and the cylindrical surface is arranged on the side with the larger diameter of the conical surface.

Further, a latticed groove is arranged on the surface of one side, facing the acetabulum or the acetabular prosthesis, of the contact layer.

Furthermore, a plurality of overflowing holes are formed in the contact layer and communicated with the pores of the porous structure layer.

Further, a plurality of overflowing holes are provided in the grid of the grid-like grooves, or a plurality of overflowing holes are provided at the intersections of the grid-like grooves.

Further, the porous structure layer is made of a metal material through 3D printing, and the contact layer is made of a polymer.

Further, the contact layer is arranged to protrude towards the axis of the pin to form a flange, and the flange is arranged between the femoral neck and the porous structural layer.

Further, the pin is inserted into the femoral head, and the femoral implant further comprises a fixing part which is arranged at a second end of the pin far away from the crown part.

Furthermore, the fixed part is the nut, and the nut passes through the helicitic texture and sets up on the round pin.

Further, the second end of the pin extending out of the femoral head is provided with a plurality of fixing holes along the radial direction of the pin.

Use the technical scheme of the utility model, the pin is fixed in the femoral head, and the tip at the pin is fixed to the coronal part, and the coronal part is fixed on the femoral head and is replaced the impaired or pathological change femoral head surface cartilage of patient through the pin, has improved femoral head pathological change region's stress environment effectively, resists the quick stress that pathological change district leads to and sinks, makes the femoral head can smoothly rotate in the acetabulum, rebuilds joint function, and then realizes the shank action among the patient daily life. Meanwhile, the coronal part of the femoral implant of the embodiment only replaces the surface of the femoral head, so that the femoral structures of more patients are reserved, and the influence of the operation on the patients is reduced to a certain extent.

Drawings

The accompanying drawings, which form a part of the present application, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 shows a schematic structural view of an embodiment of a femoral implant according to the present invention;

fig. 2 shows an enlarged partial structural schematic view at E of the femoral implant of fig. 1;

FIG. 3 shows a cross-sectional structural schematic view of a coronal portion of the femoral implant of FIG. 1;

FIGS. 4A-4D are schematic diagrams illustrating an arrangement of four examples of grid-like grooves and overflow holes on the crown surface of FIG. 3; and

fig. 5-7 illustrate a surgical flow diagram of the femoral implant of fig. 1.

Wherein the figures include the following reference numerals:

10. a pin; 11. a fixing hole; 20. a crown portion; 21. a porous structural layer; 211. a conical surface; 212. a cylindrical surface; 22. a contact layer; 23. flanging; 24. an overflowing hole; 25. a grid-shaped groove; 30. a fixed part; 80. a duct; 90. the femur; 91. a femoral shaft; 92. a femoral neck; 93. the femoral head.

Detailed Description

Aiming at the problem that total hip joint replacement in the prior art has higher early revision rate to younger patients, the hip joint surface replacement technology which is proposed as early as 50 years ago has the unique advantages of small wound, good postoperative mobility, capability of keeping more femoral side bone mass and the like, and is advocated again to treat some young and motor-active hip joint disease patients. Currently, some manufacturers have introduced individual hip implants. All of these systems have several features including: (1) the joint interface is made of high-carbon cobalt-chromium alloy; (2) fixing the acetabulum prosthesis by non-bone cement; (3) fixing the femoral side prosthesis by bone cement; (4) metal-metal hip resurfacing system. The outstanding problems with modern resurfacing prostheses are severe joint wear and high early failure rates, and remain with total hip replacement. The present application proposes improvements to the femoral side implants that address the above-mentioned problems.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

As shown in fig. 1, a femur 90 of a human body comprises a femoral shaft 91, a femoral neck 92 and a femoral head 93, wherein the femoral head 93 extends into an acetabulum of a hip joint to form a rotation friction pair with the acetabulum to realize leg swinging. The femoral implant of the embodiment is aimed at intervening the femoral head 93 in the early stage of hip arthropathy of a patient, partially replacing the femoral head 93, preventing rapid disease deterioration, and simultaneously keeping the femur of the patient as much as possible and reducing the injury to the patient. As shown in fig. 1, the femoral implant of the present embodiment includes: a pin 10 and a crown 20, wherein the pin 10 is securable in the femoral neck 92, the crown 20 is provided at a first end of the pin 10, and the crown 20 is configured to wrap around an end of the femoral neck 92 as a surface of the femoral head 93.

By applying the technical scheme of the embodiment, the pin 10 is fixed in the femoral neck 92, the crown part 20 is fixed at the end of the pin 10, and the crown part 20 is fixed on the femoral head 93 through the pin 10 and replaces the damaged or diseased femoral head surface cartilage of a patient, so that the stress environment of a femoral head diseased region is effectively improved, rapid stress collapse caused by the diseased region is resisted, the femoral head 93 can smoothly rotate in the acetabulum, the joint function is reconstructed, and further the leg movement in daily life of the patient is realized. Meanwhile, the coronal part 20 of the femoral implant of the embodiment only replaces the surface of the femoral head 93, so that more femoral structures of the patient are reserved, and the influence of the operation on the patient is reduced to a certain extent.

Moreover, the femoral implant of the present embodiment directly replaces the surface of the femoral head of the patient, and compared with total hip replacement, the technical scheme of the present embodiment does not require a lining structure in the acetabulum, so that the diameter of the femoral head after operation can be kept in the original size, thereby realizing the advantage that the large-diameter femoral head can avoid dislocation.

The pins 10 are arranged along the axis of the femoral neck 92 or at a small angle to the axis of the femoral neck 92 such that the pins 10 extend in substantially the same direction as the femoral neck 92, facilitating fixation of the crown 20.

Preferably, as shown in fig. 2, the crown portion 20 of the present embodiment includes a porous structural layer 21 and a contact layer 22, the porous structural layer 21 can be in contact with the end portion of the femoral neck, and the contact layer 22 is disposed on the outer surface of the porous structural layer 21 and can be in contact with the acetabulum or the acetabular prosthesis. The contact layer 22 has good wear resistance to replace the femoral head cartilage surface for smooth rotation in the acetabulum. The porous structure layer 21 can simulate a porous structure formed by human skeletal trabeculae, realizes similar supporting effect, and has excellent osseointegration function and physiological bone self-healing function. After the implant is implanted into a human body, bone of the femoral head can grow into the porous structure of the porous structure layer 21, so that the structural strength of the contact surface of the bone and the porous structure layer 21 is enhanced, and the crown part 20 is stably and firmly connected to the femoral head 93 of the patient.

In the femoral implant of the present embodiment, the porous structure layer 21 may be made of biomedical materials such as ceramic and titanium by a 3D printing technology, the pins 10 are dense solid structures, which can provide sufficient structural support for the crown portion 20, and the pins 10 are made of the same material as the porous structure layer 21 and can be integrally formed by the 3D printing technology. The contact layer 22 is made of polymer materials (such as polyurethane, polyvinyl alcohol gel, polylactic acid and the like) with excellent wear resistance and is formed on the surface of the porous structure layer 21 in a thermoplastic mode, an injection molding mode and the like, the contact layer 22 made of the polymer materials highly reproduces the structure of the cartilage on the surface of the femoral head of a human body, and the service life of the prosthesis is prolonged.

Specifically, as shown in fig. 3, the inner side surface of the porous structure layer 21 of the present embodiment includes a cylindrical surface 212 and a tapered surface 211 connected to each other, the tapered surface 211 is disposed gradually expanding from the first end to the second end of the pin 10, and the cylindrical surface 212 is disposed on the side where the diameter of the tapered surface 211 is larger. The taper of the conical surface 211 is about 3-5 degrees, the depth of the cylindrical surface 212 is about 5-10 mm to form a counter bore, the conical surface 211 is favorable for realizing firm fixation of the porous structure layer 21 and femoral head bone, and the counter bore formed by the cylindrical surface 212 can prevent the porous structure layer 21 from loosening caused by edge force.

Further, as shown in fig. 2 and 3, the contact layer 22 of the present embodiment is convexly disposed toward the axis of the pin 10 to form a flange 23, and the flange 23 is located between the femoral neck 92 and the porous structural layer 21 after the crown 20 is implanted, so that the contact layer 22 can be prevented from being separated from the porous structural layer 21 under a stress environment.

In order to allow smooth rotation of the coronal portion 20 in the acetabulum, as shown in fig. 4A, a latticed groove 25 is provided on a surface of the contact layer 22 on a side facing the acetabulum or acetabular prosthesis. The grid-shaped groove 25 is formed by interweaving a plurality of grooves to form a net shape, joint synovial fluid can be stored in the grid-shaped groove 25 and coated on a contact surface between the crown part 20 and the acetabulum along with the rotation of the crown part 20 relative to the acetabulum, and the lubrication effect is realized. The specific shape of the grid-shaped grooves 25 may be a square net shape as shown in fig. 4A, a hexagonal net shape as shown in fig. 4B or 4C, a diamond net shape as shown in fig. 4D, or the like.

Further, as shown in fig. 2 and 3, the contact layer 22 of the present embodiment is further provided with a plurality of overflow holes 24, and each overflow hole 24 is communicated with the pores of the porous structure layer 21. The overflowing hole 24 realizes the communication between the femoral head bone and the articular surface, so that the articular fluid generated in the bone can be supplemented to the articular surface, the dry friction is effectively avoided, the abrasion of the contact surface 22 is reduced, and the service life of the femoral implant is prolonged. Meanwhile, the femoral head bone is communicated with the joint surface, so that a closed dead space in the femoral head bone implant can be prevented, the breeding of bacteria is effectively reduced, and infection and inflammation are prevented.

Specifically, the plurality of overflowing holes 24 may be provided in a grid of grid-like grooves 25 as shown in fig. 4B, or may be provided at intersections of the grid-like grooves 25 as shown in fig. 4A, 4C, or 4D. Preferably, the diameter of the overflowing hole 24 of the present embodiment is 1 mm.

As shown in fig. 1, the pin 10 of the present embodiment is inserted into a femoral head, and the femoral implant further includes an anchoring portion 30, the anchoring portion 30 being disposed at a second end of the pin 10 remote from the crown portion 20. In the femoral implant of the present embodiment, the fixing portion 30 is a nut, which is disposed on the pin 10 by a thread structure to prevent the pin 10 from falling out of the femur 90.

As shown in fig. 1, the second end of the pin 10 extending out of the femoral head of the present embodiment is provided with a plurality of fixing holes 11 along the radial direction of the pin 10. When not secured with a nut, fixation of the femoral implant may be achieved by a steel wire passing through the fixation hole and wrapping around the femur.

In other embodiments not shown in the figures, the pin may not extend through the femur and may be secured directly in the femur by a threaded or other structure.

As shown in fig. 5 to 7, the femoral implant of the present embodiment may be generally divided into three steps when surgically implanted:

first, drilling a tunnel 80 in a patient's femur 90;

secondly, performing modeling treatment on the femoral head 93 of the patient, and prefabricating the surface of the femoral head 93 to adapt to the inner side surface of the porous structure layer 21;

thirdly, the pin 10 is inserted into the hole 80, the crown 20 is sleeved on the molded femoral head 93, and the fixation of the pin 10 is completed.

From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects:

the pin is fixed in the femoral head, the coronal part is fixed at the end part of the pin, and the coronal part is fixed on the femoral head through the pin and replaces the damaged or diseased femoral head surface cartilage of a patient, so that the stress environment of a diseased region of the femoral head is effectively improved, rapid stress collapse caused by a diseased region is resisted, the femoral head can smoothly rotate in an acetabulum, the joint function is reconstructed, and further the leg action in daily life of the patient is realized. Meanwhile, the coronal part of the femoral implant of the embodiment only replaces the surface of the femoral head, so that the femoral structures of more patients are reserved, and the influence of the operation on the patients is reduced to a certain extent.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A femoral implant, comprising:

a pin (10) fixable in the femoral neck;

a crown portion (20) provided at a first end of the pin (10), the crown portion (20) being capable of wrapping an end of a femoral neck.

2. The femoral implant according to claim 1, characterized in that said coronal portion (20) comprises a porous structural layer (21) and a contact layer (22), said porous structural layer (21) being contactable with an end portion of said femoral neck, said contact layer (22) being provided on an outer surface of said porous structural layer (21) and being contactable with an acetabulum or an acetabular prosthesis.

3. The femoral implant according to claim 2, wherein the inner side of the porous structural layer (21) comprises a cylindrical surface (212) and a tapered surface (211) which are connected, the tapered surface (211) is arranged gradually enlarging from the first end to the second end of the pin (10), and the cylindrical surface (212) is arranged on the side of the tapered surface (211) with the larger diameter.

4. The femoral implant according to claim 2, characterized in that a latticed groove (25) is provided on a side surface of the contact layer (22) facing the acetabulum or acetabular prosthesis.

5. The femoral implant according to claim 4, characterized in that a plurality of overflowing holes (24) are arranged on the contact layer (22), and the overflowing holes (24) are communicated with the pores of the porous structural layer (21).

6. The femoral implant according to claim 5, characterized in that a plurality of said overflowing holes (24) are provided in a grid of said grid-like grooves (25), or a plurality of said overflowing holes (24) are provided at the intersections of said grid-like grooves (25).

7. The femoral implant according to claim 2, characterized in that said porous structural layer (21) is made of a 3D printed metallic material and said contact layer (22) is made of a polymer.

8. The femoral implant according to claim 2, characterized in that said contact layer (22) is arranged projecting towards the axis of said pin (10) forming a cuff (23), said cuff (23) being arranged between said femoral neck and said porous structural layer (21).

9. The femoral implant according to claim 1, wherein the pin (10) is arranged to be inserted into a femoral head, the femoral implant further comprising an anchoring portion (30), the anchoring portion (30) being provided at a second end of the pin (10) remote from the coronal portion (20).

10. The femoral implant according to claim 9, wherein the anchoring portion (30) is a nut provided on the pin (10) by a threaded arrangement.

11. The femoral implant according to claim 9, wherein the second end of the pin (10) protruding out of the femoral head is provided with a plurality of fixation holes (11) in a radial direction of the pin (10).