JPS6031706Y2 - Ceramic spinal prosthesis component - Google Patents

Description

[Detailed description of the device] This device is a vertebral prosthetic member made of ceramic used for orthopedic treatment, and is configured to be used by being inserted between the bone tissues of the vertebrae for vertebral orthopedic surgery. Regarding parts.

With the development of bioengineering, treatments in which implant members (screw-type pins, blade-type, etc.) are implanted into bone tissue have become popular in the fields of dentistry and orthopedics, replacing conventional metal prosthetic members. In this case, the present applicant has provided various inventions regarding the use of ceramics, such as alumina ceramics, which are compatible with bone tissue and are not harmful to living organisms, as implant members.

For example, a ceramic bone-meat implant member having a porous contact surface disclosed in Japanese Patent Application Laid-Open No. 51-11680 Wani is implanted into bone tissue and has a large number of void channels provided in the surface portion in contact with the bone tissue. Some devices are configured to repair bone tissue by infiltrating new bone tissue into the bone tissue.

However, these intraosseous implant components are used by being implanted into bone tissue, which is a hard tissue and is relatively unloaded. It has been considered difficult to use a material that carries a large load as a repair member for vertebrae because it is unreasonable in terms of strength.

However, the vertebrae support the body weight, and when lifting or carrying objects, a considerable load is applied in the longitudinal direction of the vertebrae, and torsional force is constantly applied in response to the movement of the human body, so the three-dimensional Using this type of intraosseous implant member having a large gap as a prosthetic member is difficult in terms of strength due to the nature of the external force.

For this reason, methods for repairing vertebrae include fitting a strong artificial metal prosthetic member into the affected area, or removing and transplanting the human ilium, which is the same soft tissue as the bone tissue of the vertebrae. It is taken.

However, when using artificial metal prosthetic members, there are problems in terms of compatibility with living tissue and toxicity due to in-vivo corrosion, and the method of transplanting the iliac bone is time-consuming and patient. It caused tremendous pain and burden.

The present invention was devised in view of the fact that conventional vertebral prosthesis methods (means) exist under such circumstances.The purpose of this invention is to be compatible with the human body, not cause any harm to the human body, and to reduce the burden on the vertebrae. It is an object of the present invention to provide a prosthetic member that has sufficient strength to withstand even the most severe conditions and has excellent weight retention ability.

Hereinafter, the vertebral prosthetic member of the present invention will be explained in detail.

The invented vertebral prosthesis member (hereinafter referred to as the "present invented member").

) is shaped like a ceramic body that is compatible with the human body and is not harmful to living organisms, and can be placed directly on the vertebra where the prosthesis is to be performed.
It is constructed so that it can be used as a vertebral prosthesis just by fitting it into the body.
This is because a large number of columnar gaps having an effective opening diameter of 0.2 mmφ or more necessary to allow penetration and development are provided in the longitudinal direction, and the ceramic body as a whole is configured in a lotus root shape or a honeycomb shape.

The effective opening diameter here refers to the opening diameter necessary for adjacent bone tissue to grow and invade on both the upper and lower surfaces of the member of the present invention, and is referred to as the so-called inter-opening diameter.

Therefore, as long as the diameter is a value that allows growth and invasion of adjacent bone tissue, the diameter of the internal columnar gap is not critical.

Furthermore, the fact that the effective opening diameter of the columnar gap is 0.2 mm or more means that adjacent bone tissue may enter the interior of the member of the present invention (
Since the vertebral bodies that make up the vertebrae are more flexible than hard ceramic bodies, the bone tissues of the vertebral bodies easily fit into the columnar gaps of the members of the present invention, and this has already been confirmed through medical experiments.

) At the prosthetic site, a composite structure consisting of a ceramic body and bone tissue that has invaded and proliferated is formed, which is strong against loads acting in the vertical direction of the vertebrae, and is also strong enough to withstand forces acting in the torsional direction. This is an indispensable requirement for achieving the unique effects of the present invention, such as having sufficient strength and maintaining force (fixing force) to easily perform vertebral prosthesis.

The ceramic body is shaped appropriately according to the area to be prosthesized (for example, cervical vertebrae, thoracic vertebrae, lumbar vertebrae, and their intervertebral discs, etc.) so as not to interfere with the original functions of the vertebrae as a whole. Needless to say, it is manufactured by a known method of compacting and firing alumina or mullite ceramic.

Next, the members of the present invention will be described in more detail with reference to some preferred embodiments.

FIG. 1 shows a vertebral prosthesis member used for prosthesizing an intervertebral disc.

Note that in the following description, 7 indicates a resected intervertebral disc, and 7 indicates a healthy intervertebral disc that still remains in the human body after vertebral prosthesis.

The intervertebral disc 7 is a fibrous soft tissue that interconnects the vertebral bodies 100 constituting the vertebra, and has a so-called shock absorber function when viewed from the vertebra as a whole.

Such a situation in which an intervertebral disc needs to be prosthesized occurs, for example, when the intervertebral disc must be removed due to a disorder such as a herniated intervertebral disc, and in such a case, the member of the present invention works extremely effectively.

For example, as shown in FIG. 2, a vertebral body 1 with an intervertebral disc 7 removed
00, 100, the member of the present invention shaped into an appropriate shape may be inserted into the gap between the vertebral bodies 10O, 100. If only a part of the vertebral bodies 10O, 100 is excised, the member of the present invention may be inserted in the space between the vertebral bodies 10O, 100 depending on the excised part. Needless to say, it is only necessary to select an appropriate shape and insert it.

When the intervertebral disc 7 is prosthesized in this way, the adjacent bone tissues 100, 100 enter through the through holes 41 provided on both the upper and lower surfaces of the ceramic body 5, and the member 50 of the present invention is combined with the ceramic body based on the principle described above. Together with the proliferated and invaded bone tissue, a composite tissue is formed, and the adjacent upper and lower vertebral bodies 100 and 1°O are firmly connected to each other, forming a new tissue that constitutes the vertebrae.

In this case, the hard ceramic body 5 is replaced with the intervertebral disc 7, which is a soft tissue that is naturally highly contractile.
Therefore, the so-called shock absorber function that a healthy intervertebral disc inherently has cannot be performed, and the same is true in the case of iliac (hard tissue) transplantation described above.

Therefore, the artificial metal prosthetic members conventionally used as vertebral prosthetic members have a poor compatibility with living tissue and sometimes have an adverse effect on the human body (biotoxicity), but the present prosthesis made of a ceramic body Naturally, this can be avoided by using a component, so compared to the previous method of transplanting the ilium and performing a vertebral prosthesis, this troublesome ilium harvesting operation puts a great burden on the patient. Since there is no need to perform the above procedures, this method brings extremely great benefits both surgically and to the living body.

Furthermore, it goes without saying that the member of the present invention can also be used as a prosthetic member, including the defective part of the vertebral body itself constituting the vertebrae.

For example, when performing a prosthesis for a defective part of a vertebra including the vertebral body, a ceramic is manufactured in the desired shape according to the part to be prosthesized, as shown in Fig. 3, and the adjacent bone tissue is
Threaded portions 61 and 62 may be provided at the upper and lower circumferential ends of the surface 12 to be joined to the 0 and 100 parts.

Needless to say, it is preferable that these threaded portions 61 and 62 be configured to have a reverse threaded relationship with each other in order to facilitate and ensure screw fixation to the adjacent bone tissues 100, 100.

FIG. 4 shows the member of the present invention shown in FIG.
It is a diagram showing a state in which a prosthesis has been applied between

Other preferred embodiments of the members of the present invention are shown in FIGS. 5, 6, and 7.
Examples include those shown in FIG. 8 and FIG. 9.

Fig. 5 shows a case in which grooves 42 are provided in place of the blind holes 41 in Fig. 1 on the upper and lower surfaces 1°2 that connect with the bone tissue, and Fig. 6 shows the present invention shown in Fig. 1. An intervertebral disc in which a plurality of rounded protrusions 31 are provided on both upper and lower surfaces of a member 50 to facilitate fitting into and sinking into adjacent bone tissue and to further strengthen communication with the adjacent bone tissue. For example, FIG. 7 shows a vertebral body prosthesis in which a plurality of rounded protrusions 63 are provided in place of the threaded portions 61 and 62 at both the upper and lower ends of FIG. In the figure, the through holes 41 have a cross-sectional outline of a mandarin orange, and in Figure 9, the through holes 41 have a honeycomb shape.
Although these are shown below, it goes without saying that these additional measures may be replaced and adopted as necessary.

Furthermore, in addition to these, it goes without saying that by forming the inventive member according to the shape of the vertebral part to be prosthetic, it is possible to perform prosthesis for any part of the vertebra, especially including the joint part. When a vertebral component is to be prosthesized, an artificial joint part that can be tilted forward to a certain extent, preferably within 10 degrees, may be provided in the middle part of the ceramic body as necessary.

As mentioned above, the component of the present invention has a structure in which a ceramic body that is compatible with living tissues and is not harmful to living organisms can be used as a vertebral prosthetic component in place of conventional metal prosthetic components. Its advantage is that instead of bone grafting, it is possible to easily perform vertebral prosthesis by simply inserting it into the area of the vertebra where the prosthesis is to be performed, and at the same time, it is possible to easily perform vertebral prosthesis by simply inserting it into the area of the vertebra where the prosthesis is to be performed. In order to invade and proliferate tissue, form a composite tissue with the ceramic body and new bone tissue, and thereby firmly connect adjacent bone tissue,
It is possible to maintain a strong connection state even against the load applied to the vertebrae and the force in the torsional direction, and it is extremely useful, bringing about revolutionary advances in orthopedic surgery.

[Brief explanation of drawings]

Fig. 1a is a perspective view showing an embodiment of the inventive member (for intervertebral disc), Fig. 1 is a partially cutaway perspective view of the inventive member, and Fig. 2 shows the inventive member shown in Fig. 1a. FIG. 3 is a perspective view showing another embodiment of the inventive member (for the connecting portion between the intervertebral disc and the vertebral body), and FIG. 4 is the inventive member shown in FIG. 3. Fig. 5a is a perspective view showing another embodiment of the inventive member (for intervertebral discs), Fig. 5 is a partially cutaway perspective view thereof, Fig. 6 is FIGS. 8 and 9 are perspective views of a third embodiment of the inventive member for an intervertebral disc, and FIG. 7 for a connecting portion between an intervertebral disc and a vertebral body. Explanation of symbols 1...Top surface, 2...Bottom surface,
3...Protrusion, 4...Columnar gap, 41...
...Through hole, 42...Blind hole, 5...
Ceramic body, 7...Intervertebral disc, 100...
...Vertebral body, 61, 62...Screw part, 63...
···protrusion.

Claims (1)

[Claims for Utility Model Registration] 1. A ceramic body 5 formed in a shape and size similar to that of the intervertebral disc 7 and/or the vertebral body 100; 1
, 2 to the inside of the bone tissue 7 and or 100
An effective opening diameter of 0.2 mm allows the proliferation and invasion of
A vertebral prosthetic member made of ceramic and having a large number of columnar gaps 4 in the axial direction of φ or more and having an approximately lotus root shape or honeycomb shape as a whole. 2 The columnar gap 4 is located on both upper and lower surfaces 1 of the ceramic body 5,
2. The member according to claim 1, which is a blind hole 41 that extends inward from each of the holes 41 and ends. 3 Utility model registration claim 1, wherein the columnar gap 4 is a through hole 42 passing through the ceramic body 5 in the longitudinal direction
Components listed in section. 4. The member according to claim 1, wherein the ceramic body 5 is an alumina interlocking crystal body, an alumina ceramic body, or a mullite ceramic body.