JP3469994B2 - Iliac crest prosthesis - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iliac prosthesis member that prostheses a bone defect portion produced by collecting an iliac crest for use as a bone graft that is generally performed in the field of orthopedics. Is.

[0002]

2. Description of the Related Art Conventionally, in the field of orthopedics, an intestine shown in FIG. 10 for the purpose of transplantation in bone joint surgery such as subtotal extirpation of the vertebral body, vertebral body fusion or prosthesis of a bone defect after tumor resection. Often, for example, a portion of the bone W'indicated by a symbol I in the drawing is collected and used. However, after collecting the iliac bone, it often causes deformation of the iliac crest, deformity, anterior iliac fracture, and damage to surrounding nerves.

This causes complaints such as discomfort when wearing a corset or using a belt. Then, as a method of preventing these, a bone defect portion is prostheticly repaired by using bone cement at the iliac end, or as shown in FIG. 11, an iliac prosthesis member T1 composed of a ceramic material such as alumina is used to graft bone. I was trying to reproduce the iliac crest morphology after collection.

Initially, the iliac crest prosthesis member T1 was of a simple curved type and merely reproduced the shape in a two-dimensional manner. When all layers including the iliac crest are collected, the bone defect portion D becomes wide as shown in FIG. 12, and even if the iliac crest prosthesis member T1 as described above is used, the three-dimensional morphology can be completely reproduced. It is difficult to do so, and it is necessary to make the engaging groove portion w1 formed on the bone side corresponding to the engaging portion K large. Therefore, the residual bone amount locally becomes too small, and the iliac crest Prosthetic member T1
There was a problem of missing bones when driving.

On the other hand, in Japanese Patent Laid-Open No. 4-95020, the shape of the iliac crest prosthesis member is curved in two directions to have a three-dimensional curved surface so as to match the original iliac crest shape, or to fix it. An attempt was made to solve this problem by an iliac crest prosthesis member characterized in that both ends of the iliac crest prosthesis member for joining are curved to match the curve of the iliac crest shape.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The No. 20 iliac crest prosthesis member was a very effective means for more accurate and three-dimensional reproduction of the iliac crest shape.

However, even if the prosthesis member is designed and manufactured with the utmost care, it is inevitable that the bone shape and the prosthesis member do not conform to each other locally. Therefore, the engaging groove formed on the bone side is formed. Since it becomes large, the residual bone width locally becomes very thin, which may cause a bone defect.

[0008] Therefore, in order to cope with such a situation and a problem, an iliac crest prosthesis member which can be modified in shape during the operation has been desired.

[0009]

In order to solve the above-mentioned problems, the present invention firstly provides a prosthesis member which is integrally formed at both ends of a curved rod-shaped main body with engaging portions for projecting bones. There is provided an iliac crest prosthesis member having a bendable portion formed in the central portion of the main body portion. Further, the present invention provides an iliac crest prosthesis member in which at least engagement portions with bones formed at both ends of a main body having a curved rod shape are coated with apatite.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an iliac crest prosthesis member 1 according to this embodiment.
0, the iliac crest prosthesis member 10 is made of a ceramic material such as alumina or zirconia or a metal material such as a titanium alloy, and the main body portion 2 has two curved rod-shaped rod-shaped members connected by a hinge at a central portion. Flexible part 3 as a structure
Are linked together. Further, on both ends of the main body portion 2, there are provided projection-like engaging portions 4 for driving in a groove portion w1 formed by cutting a part of the iliac crest W shown in FIG. It is formed integrally with the main body 2.

The iliac crest prosthesis member 10 includes the bendable portion 3 described above.
Thus, even if there is a slight shape mismatch between the engaging portion 4 and the groove w1 formed in the iliac crest W during the operation of setting the prosthesis site, quick and simple shape correction is possible. Therefore, the fixing engagement portion 4 can be driven into the iliac crest W without difficulty, and the thin portion of the iliac crest W need not be lost due to an unreasonable load.

Next, FIG. 3 shows an iliac crest prosthesis member 1 according to another embodiment of the present invention. This iliac crest prosthesis member 1 is made of a titanium alloy, and its main body portion 2 has a curved rod shape. Then, a bendable portion 3 having a thickness t = 2 to 10 mm, which is narrower than the other portions of the main body 2, is formed in the central portion of the main body 2. In addition, a protrusion-shaped engaging portion 4 for driving the portion of the iliac crest W shown in FIG. 2 into a groove portion w1 formed by cutting the bone and embedding and fixing the portion is integrally formed with the main body portion 2. At the same time, a titanium alloy is sprayed on the engaging portion 4 and its surroundings to provide a rough surface, and then the apatite 5 is coated with good adhesion by a known spraying method.

Further, as shown in FIG. 3, the iliac crest prosthesis member 1 is constructed by passing nylon fibers, silk threads, metal wires, etc. for fixation into the intestines in the vicinity of the engaging portions 4, 4 at both ends or in the central portion 3. One through hole H for fastening the bone crest prosthesis member 1
It is also possible to provide about 20 pieces.

By the way, as described above, the iliac crest prosthesis member 1 shown in FIG.
The flexible portion of the thin-walled portion having a thickness t = 2 to 10 mm,
Further, the reason why the apatite 5 is coated on the engaging portions 4 on both ends is as follows.

First, the reason why the iliac crest prosthesis member (hereinafter abbreviated as a prosthesis member) 1 is made of a titanium alloy is that intracorporeal ceramic materials such as alumina and zirconia and polymer materials are used during surgery. Shape modification is impossible or difficult, but it is possible if it is a metal material, and titanium alloy is more suitable than other biological metal materials such as stainless steel and Co-Cr alloy. This is because the degree of safety for the living body is extremely high.

In the prosthesis member 1, the body portion 2
The thickness t of the bendable portion 3 is set to 2 to 10 mm,
During the installation operation of the prosthesis member 1, it is judged that it is better to slightly modify the shape of the prosthesis member 1 for a good combined fitting of the groove portion w1 of the iliac crest W and the engagement portion 4 of the prosthesis member 1. In this case, or when correction is necessary, the above-mentioned shape correction can be performed quickly and easily by using a hand tool such as a wrench. On the other hand, when the thickness t is less than 2 mm, a high load may be applied after the prosthesis and the prosthetic member 1 may be largely bent. On the other hand, when the thickness t is greater than 10 mm, the shape modification can be easily performed. There is a risk that you cannot do it.

Next, the reason why the engaging portion 4 is coated with the apatite 5 is that the thickness (pre-coating thickness) t1 of the titanium alloy forming the engaging portion 4 is changed by coating the apatite 5 as shown in FIG. Apatite 5 that can be made as small as possible and has excellent osteoinductive ability
However, because it is replaced with new bone after a certain period of time, as a result,
This is because a sufficient amount of bone can be secured at the engaging portion between the engaging portion 4 and the iliac crest W. As a result, bone defects are very unlikely to occur even when the site is subjected to a high load.

At this time, in the apatite 5, the post-coating thickness t2 of the engaging portion 4 is the width t3 of the corresponding groove portion w1 on the bone side.
It should be slightly larger than By doing so, the engaging portion 4 is press-fitted (by hammering) into the groove portion w1 and fixed, so that there is no wobbling or dislocation of the prosthesis member 1 and bone formation is achieved early. Can be expected to be done. The coating of the apatite 5 on the engaging portion 4 is an extremely effective technique not only when the bendable portion 3 is formed on the prosthesis member 1 but also when the bendable portion 3 is not formed.

Next, FIGS. 5 to 7 show variations in the shape of the engaging portion 4 of the prosthetic member 1. As shown in FIG. 5, the shape of the engaging portion 4 may be such that the tip portion 4a is thicker than the root portion 4b in order to prevent the engagement portion 4 from coming off after being fixed, and as shown in FIG. The part 4 has a straight shape, or, as shown in FIG. 7, the engaging part 4 has a curved shape similar to this curvature in accordance with the curvature of the main body 2 of the prosthetic member 1. May be.

8 to 9 show a prosthetic member according to another embodiment. The prosthesis member 1 shown in FIG. 8 is curved in two directions, that is, when viewed from the upper surface 6 [FIG. (A)] and the lateral surface 9 [FIG. (B)], respectively, with curvature radiuses R1 and R2. I am in a shape. Then, the radius of curvature R1 in the horizontal direction
Is preferably R = 10 to 500 mm,
Similarly, if the radius of curvature R2 in the vertical direction is R =
It is preferably 10 to 500 mm. With these two curves, for example, when the bone is resected over a wide area, it is possible to more accurately reproduce the three-dimensional shape of the iliac crest W.

FIG. 9 shows a prosthesis member 1 according to another embodiment. The prosthesis member 1 is provided with a plurality of spikes 9 on a lower surface 8 of the main body portion 2 facing the iliac crest W, and the spikes 9 are attached to the bone. The prosthesis member 1 can be fixed more firmly by being inserted into the.

The present invention is not limited to the above embodiment, and any form can be adopted without departing from the object of the invention.

[0023]

As described above, the iliac crest prosthesis member of the present invention is a prosthesis member formed by integrally forming projecting bone engaging portions on both ends of a curved rod-shaped main body. In that, by forming a bendable portion in the central portion of the main body,
A simple shape correction is possible during the operation of installing the prosthesis member. Therefore, the fixing engagement portion can be driven into the iliac ridge without difficulty, and it is not necessary to remove the thin portion of the iliac ridge due to an unreasonable load.

Further, in the iliac prosthesis member according to the present invention, since the apatite coating is applied to at least the bone engaging portions formed at both ends of the curved rod-shaped main body portion, the thickness of the engaging portion (pre-coating thickness) ) Can be made as small as possible, and apatite, which has an excellent osteoinductive ability, is replaced with new bone after a certain period of time, and as a result, at the engaging portion between the engaging portion and the iliac crest, A sufficient amount of bone can be secured, so that even if a high load is applied to the site, bone loss is extremely unlikely to occur, which is an extremely excellent effect.

[Brief description of drawings]

FIG. 1 is a perspective view of an iliac crest prosthesis member of the present invention.

2 is a perspective view showing an iliac crest for fixing the prosthetic member of FIG. 1. FIG.

FIG. 3 is a perspective view of an iliac crest prosthesis member of the present invention according to another aspect.

FIG. 4 is a plan view showing a state in which the prosthetic member of FIG. 1 is fixed to the place of FIG. 2, and the prosthetic member shows a region A in FIG. 1 from the upper side.

5 is a top view showing a region A of FIG. 1. FIG.

FIG. 6 is a top view showing a region A of FIG.

FIG. 7 is a top view showing a region A of FIG.

FIG. 8 shows an iliac crest prosthesis member according to another embodiment, (a) is a top view and (b) is a perspective view from the lateral side.

9A and 9B show an iliac crest prosthesis member according to another embodiment, FIG. 9A is a top view, and FIG. 9B is a perspective view from the lateral side.

FIG. 10 is a plan view of the iliac bone.

FIG. 11 is a perspective view of a conventional iliac crest prosthesis member.

FIG. 12 is a perspective view showing a bone-cutting installation site of the iliac prosthesis member.

[Explanation of symbols]

1 (iliac crest) prosthesis member 2 body 3 Flexible part 4 Engagement part 4a tip part 4b Root site 5 Apatite 6 upper surface 7 side 8 Lower surface 9 spikes t, t1, t2, t3 thickness, thickness R1, R2 radius of curvature W iliac crest w1 groove

Claims (3)

(57) [Claims] 1. A prosthesis member having integrally formed projection-shaped bone engaging portions at both ends of a curved rod-shaped body portion, wherein a bendable portion is formed at a central portion of the body portion. A iliac crest prosthesis member formed by 2. The iliac crest prosthesis member according to claim 1, wherein the bendable portion has a thickness of 2 to 10 mm when the main body is made of titanium alloy. 3. A prosthesis member integrally formed with protruding bone-engaging portions at both ends of a curved rod-shaped main body, wherein at least the engaging portions are coated with apatite. Iliac crest prosthesis member.