KR101194775B1 - Buffered hip resurfacing device - Google Patents

Abstract

The present invention relates to a surface replacement implant device having a buffer, and more particularly, in a hip surface replacement implant device that resections the surface of the femoral head and places an artificial hip joint thereon, between the femoral head and the hemispherical artificial head. A surface displacement implant device having a flexible buffer in the shape of a truncated cone with a roof.
According to the present invention, by using the roof-shaped buffer of the truncated cone to prevent the slip between the buffer and the head, regardless of the state of the femoral ball head, the appropriate load is transmitted to the upper part of the femoral ball head, all the parts of the femoral ball head healthy state The stress distribution is evenly distributed to maintain.
In addition, according to the present invention, the buffer is made of a porous or rough surface in contact with the head to achieve osteo-integration with the femoral head so that it is sealed to prevent other external particles from entering, and mutually sliding with the artificial head This allows for even distribution of compressive stress to the femoral head.

Description

Hip surface replacement implant device with a buffer {BUFFERED HIP RESURFACING DEVICE}

The present invention relates to a surface replacement implant device having a buffer, and more particularly, in a hip surface replacement implant device that resections the surface of the femoral head and places an artificial hip joint thereon, between the femoral head and the hemispherical artificial head. A surface displacement implant device having a flexible buffer in the shape of a truncated cone with a roof.

1 is a view showing a state in which the conventional head fixed surface replacement device 100 of the buffer fixing method installed in the pelvis. Referring to the drawings, when a load is applied to the artificial head 110, the load is transmitted to the buffer sleeve 120 through the inner surface of the artificial head 110 with a compressive force. This compressive force causes elastic deformation of the buffer sleeve 120 and increases the compressive force between the buffer sleeve 120 and bone tissue. The surface of the head of the femur 11 is pre-treated to have a slope corresponding to the inner surface of the buffer sleeve 120. Accordingly, the compressive force applied to the bone tissue through the inner surface of the buffer sleeve 120 is uniformly distributed. In addition, when bone tissue grows due to bone remodeling, the outer surface of the buffer sleeve 120 slides with respect to the inner surface of the artificial head 110. Accordingly, the inner surface and the bone tissue of the buffer sleeve 120 can be maintained in a constantly close state.

As such, the band compression is possible and the roofless cushioning sleeve 120 is conventionally surrounded by the femoral head 11 in such a manner that it depends entirely on the inclined lateral frictional force between the femoral head 11 and the cushioning sleeve 120. Slip between the femoral head 11 and the buffer sleeve 120 was to be suppressed. However, in this case, if the friction coefficient between the femoral head 11 and the buffer sleeve 120 is not large enough compared with the friction coefficient between the artificial head 110 and the buffer sleeve 120, the buffer sleeve 120 is the femoral head 11 There was a problem that can slide down.

In addition, the sliding movement between the femoral ball head 11 and the buffer sleeve 120 has a problem that interferes with the osteo-integration between the femoral ball head 11 and the buffer sleeve 120 by generating a soft tissue network in the bone.

In addition, by using the roofless buffer sleeve 120, the load is transmitted to the bone only through the side of the buffer sleeve 120, there was a problem that the stress is not enough to transfer the upper part of the head.

The present invention was devised to solve such a problem, and by using a buffer of the shape of the roof with a truncated cone to prevent slipping between the buffer and the head regardless of the condition of the femoral ball head, the appropriate load is transmitted to the upper part of the femoral ball The goal is to distribute the stress evenly to all parts of the femoral head.

It also aims to ensure that the contact area with the head consists of a porous or rough surface so that the buffer achieves osteo-integration with the femoral head so that it is sealed from other foreign particles.

In addition, the purpose is to distribute the even compressive stress to the femoral ball head by allowing the mutual head and the sliding by the buffer.

In order to achieve the above object, the surface replacement implant apparatus for cutting the surface of the femoral ball head according to the present invention and replacing it with an artificial head, has a generally hemispherical outer support surface and an inclined and smooth inner support surface, and the inner surface. An artificial head having a bottom surface connected to the support surface; And a truncated conical shape having a hollow portion, the outer surface contacting the inclined inner support surface of the artificial head and shorter than the length of the inner support surface, the inner surface contacting the inclined side surface of the femoral ball head tissue, and the truncated cone shape. A buffer having a roof covering a small diameter cross section of upper and lower circular cross-sections of the upper and lower circular cross sections, wherein a predetermined distance is provided between the roof of the buffer and the bottom surface of the artificial head when the buffer is inserted into the artificial head. The roof is supported by the inner surface in contact with the flat upper surface of the femoral ball head tissue to prevent the buffer from slipping down the femoral ball head and to evenly transmit stress to the upper part of the head, the inner surface of the buffer and the buffer The inner face of the roof has a rough surface, the outer face of the buffer and the outer face of the roof of the buffer A plurality of fine particles having a smooth surface and having bone affinity are distributed on the inner surface of the buffer and the inner surface of the roof of the buffer.

The artificial head may be made of a ceramic material.

The artificial head may be a metal reinforcing inner support surface of the ceramic material.

The artificial head may be made of a metal material.

The artificial head may be made of a cobalt-chromium alloy.

It is preferable that the artificial head is covered with a material having high wear resistance.

According to another aspect of the present invention, the buffer used for the surface replacement implant apparatus for cutting the surface of the femoral head and replacing it with an artificial head has a truncated conical shape having a hollow portion, and an inclined inner support surface of the artificial head. An outer surface in contact with and shorter than a length of the inner support surface; Internal surface in contact with the inclined side of the femoral head bone tissue; And a roof covering a small diameter cross section of the truncated conical top and bottom, wherein the roof is supported in contact with a flat upper surface of the femoral head bone tissue to prevent the buffer from sliding down the femoral ball head. Stress is evenly transmitted to the upper portion of the inner surface and the inner surface of the roof has a rough surface, the outer surface and the outer surface of the roof has a smooth surface, the inner surface and the inner surface of the roof Many microparticles | fine-particles which have chemical conversion are distributed.

The buffer may be made of a metal material.

The buffer may have a plurality of pores or holes that facilitate compression deformation.

According to the present invention, by using the roof-shaped cone of the buffer to prevent slipping between the buffer and the head regardless of the condition of the femoral ball head, the appropriate load is transmitted to the upper part of the femoral ball head to ensure that all parts of the femoral ball head are healthy. There is an effect of evenly distributed stress to maintain.

In addition, the buffer has an effect of being sealed to prevent the entry of other external particles by forming a porous or rough surface of the contact portion with the head to achieve osteo-integration with the femoral head.

In addition, the buffer has the effect of allowing even sliding with the artificial head to distribute the even compressive stress in the femoral head.

1 is a view showing a state in which the conventional head fixed surface replacement device of the buffer fixing method installed in the pelvis.
2 is a view showing a state in which a surface replacement implant device having a buffer according to the present invention installed in the pelvis.
3 is a view showing an artificial head to be used in the surface replacement implant device having a buffer according to the present invention.
4 is a cross-sectional view of the artificial head portion shown in FIG.
5 shows a buffer for use in a surface replacement implant device having a buffer according to the present invention.
6 is a cross-sectional view of the buffer shown in FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

2 is a view showing a state in which the surface replacement implant device 200 having a buffer 220 according to the present invention installed on the pelvis 260.

The surface replacement implant device 200 is made of a rigid material to replace the surface of the femoral ball head 21 and has a spherical shape on the outside and a conical shape on the inside, and a conical shape with a roof on the outside. And the outside has a smooth surface and the inside includes a buffer 220 having a very rough surface.

Compared to the case where there is no buffer, it is very easy to install the artificial head (210) in place. When installed in place, the maximum range of motion of the joint can be secured, and the femoral head, which is a weak point of the femoral head surface replacement implant system, can be prevented. In addition, in the absence of a buffer, the artificial head is directly connected to the bone, and partial bone fusion occurs, whereby the stress distribution is concentrated to where the bone is fused. However, with a buffer, stress is distributed evenly over the head regardless of bone fusion. Even stress distribution is very important in maintaining the health of the femoral head, and the health of the femoral head prevents the fracture of the femoral head.

Meanwhile, in some cases, the femoral head 21 may be inadequate or a sufficient friction force may not be generated between the buffer 220 and the femoral head 21 due to the remodeling process of the femoral head 21. In this case, the mutual sliding movement between the buffer and the femoral head causes soft tissue membranes at the buffer-bone interface to inhibit the fusion of the buffer-bone interface, leading to the relaxation of the artificial head, and thus the function of the implant device. Sliding motion should be restrained as much as possible.

The buffer with the roof 223 (see FIG. 6) according to the present invention facilitates stress transfer to the upper part of the head while blocking the possibility of the buffer 220 sliding down the femoral ball 21 as described above.

The femoral head 21 is processed into a flat truncated conical shape, and then installs a buffer 220 slightly smaller than the processed femoral ball 21 on the femoral ball 21 by an interference fit method. . Above the buffer 220, the artificial head (210) having a spherical shape and a truncated cone-shaped hole is inserted therein, and the artificial head (210) is fitted to the acetabular (22) portion of the pelvis (23).

In this case, the artificial head 210 receives an external force and slides into the buffer 220 to apply shear stress and compressive stress to the buffer 220, and the stress is evenly applied through the ceiling and the wall of the buffer 220. It is delivered to the head 21 so that all parts of the femoral head 21 are evenly distributed in stress. In addition, the buffer 220, the contact portion with the head is made of a porous or rough surface to achieve osteo-integration with the femoral ball 21 is sealed to prevent other external particles from entering, and the buffer 220 and artificial The heads 210 allow the sliding to be evenly distributed to the femoral ball head 21 by allowing each other to slide.

Meanwhile, a free space 230 is provided between the artificial head 210 and the buffer 220 so that the artificial head 210 may slide down the surface of the buffer 220.

3 is a view showing the artificial head 210 used in the surface replacement implant device 200 having a buffer according to the present invention, Figure 4 is a cross-sectional view of the artificial head 210 shown in FIG.

The artificial head 210 has a generally hemispherical outer support surface 211, an inwardly inclined and smooth inner support surface 212, and a bottom surface 213 connected to the inner support surface 212. .

The artificial head 210 is made of a metal or a ceramic that both the inside and the outside surface is strong and smooth to minimize wear, and in some cases may be configured to reinforce the inner support surface of the ceramic material with a metal. Cobalt-chromium alloy may be used as the metal material, but is not necessarily limited thereto. In addition, as described above with reference to FIG. 2, a free space 230 is provided between the artificial head 210 and the buffer 220 so that the artificial head 210 can slide down the surface of the buffer 220. .

5 is a view showing a buffer 220 used in the surface replacement implant apparatus 200 having a buffer according to the present invention, Figure 6 is a cross-sectional view of the buffer 220 shown in FIG.

The buffer 220 has a truncated conical shape having a hollow portion, an outer surface 221 in contact with an inclined inner support surface of the artificial head 210, an inner surface 222 in contact with an inclined side surface of the femoral ball head tissue, and The upper and lower circular cross section of the truncated conical shape comprises a roof 223 covering the small diameter cross section and the inner surface is in contact with the flat upper surface of the femoral ball head bone tissue. The buffer 220 is preferably made of a metal material.

The outer surface 221 of the buffer 220 and the outer surface 225 of the roof 223 allow sliding with the artificial head 210 to allow even compressive stress to be distributed to the femoral head 21. It is desirable to be made of a material that is strong and smooth to minimize wear.

The inner surface 222 of the buffer 220 and the inner surface 224 of the roof 223 preferably have a porous or rough surface, in particular the inner surface 222 and to facilitate bone fusion with the femoral ball head 21. It is preferable that a plurality of fine particles having bone affinity, that is, bone affinity, are distributed on the inner surface 224 of the roof 223. As the bone affinity, all kinds of calcium phosphate having the property of promoting hydroxyapatite, calcium phosphate, animal bone powder and other bone growth can be used. In addition, although it does not actively promote bone growth like ceramic particles and metal particles, the in-growth of the bone has been proved and the friction force and surface area of the buffer 220 have been widened so that the buffer 220 can be quickly and quickly Particles that aid in tight fixation may also be used.

The bone affinity particles are preferably distributed in the inner surface 222 of the buffer 220, the inner surface 224 of the roof 223, and the inner region thereof. As time passes, the bone affinity particles dissolve and are absorbed into the bone. At this time, since the bone grows into the space where the bone affinity particles were, the buffer 220 may be firmly fixed to the bone. In addition, since the bone affinity particles are not only distributed on the inner surface 222 of the buffer 220 and the inner surface 224 of the roof 223, but also in an inner region adjacent to the inner surface 222 and the roof 223. Bone affinity particles distributed on the inner surface 224 of the can be continuously promoted bone growth even after the bone is absorbed

In addition, the buffer 220 may have a plurality of pores or holes to facilitate compression deformation.

11: thigh head 12: acetabular 13: pelvis
100: buffer head replacement device
110: artificial head head 120: buffer sleeve
130: space for movement of the artificial head
21: thigh head 22: acetabular 23: pelvis
200: surface replacement implant device with buffer
210: artificial head 211: outer support surface
212: internal support surface 213: bottom surface
220: buffer 221: outer surface
222: inside 223: roof
224: inside face of the roof 225: outside face of the roof
230: free space for movement of the artificial head

Claims (11)

A surface replacement implant device for cutting the surface of the femoral head and replacing it with an artificial head,
An artificial head having a generally hemispherical outer support surface, an inwardly inclined and smooth inner support surface, and a bottom surface connected to the inner support surface; And
A truncated conical shape having a hollow portion, the outer surface contacting the inclined inner support surface of the artificial head and shorter than the length of the inner support surface, the inner surface contacting the inclined side surface of the femoral ball head tissue, and the truncated conical shape. Buffer with roof covering small diameter cross section of upper and lower circular section
Including,
When the buffer is inserted into the artificial head, a predetermined gap is provided between the roof of the buffer and the bottom surface of the artificial head. To prevent the buffer from slipping down the femoral head and to distribute stress evenly over the head,
The inner surface of the buffer and the inner surface of the roof of the buffer have a rough surface,
The outer surface of the buffer and the outer surface of the roof of the buffer have a smooth surface,
In which a plurality of fine particles having bone affinity are distributed on the inner surface of the buffer and the inner surface of the roof of the buffer
Surface replacement implant device having a buffer, characterized in that. The method according to claim 1,
The artificial head is,
Made of ceramic material
Surface replacement implant device having a buffer, characterized in that. The method according to claim 2,
The artificial head is,
Reinforcing metal with internal support surface of ceramic material
Surface replacement implant device having a buffer, characterized in that. The method according to claim 1,
The artificial head is,
Made of metal
Surface replacement implant device having a buffer, characterized in that. The method of claim 4,
The artificial head is,
Consisting of cobalt-chromium alloys
Surface replacement implant device having a buffer, characterized in that. The method according to claim 1,
The artificial head is,
Covered with abrasion resistant material
Surface replacement implant device having a buffer, characterized in that. As a buffer used for a surface replacement implant device that removes the surface of the femoral head and replaces it with an artificial head,
Has a truncated cone shape with a hollow portion,
An outer surface contacting the inclined inner support surface of the artificial head and shorter than a length of the inner support surface;
Internal surface in contact with the inclined side of the femoral head bone tissue; And
Roof covering a small diameter cross section of the truncated cone shape
Including,
The roof is supported by the inner surface in contact with the flat upper surface of the femoral ball head tissue to prevent the buffer from sliding down the femoral ball head and to evenly transmit stress to the upper part of the head,
The inner surface and the inner surface of the roof have a rough surface,
The outer surface and the outer surface of the roof have a smooth surface,
Having a plurality of fine particles having bone affinity distributed on the inner surface and the inner surface of the roof
A buffer used in the surface replacement implant device, characterized in that. The method of claim 7,
The buffer is
Composed of metallic materials
A buffer used in the surface replacement implant device, characterized in that. delete The method of claim 7,
With multiple pores or holes to facilitate compressive deformation
A buffer used in the surface replacement implant device, characterized in that. delete

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