JPH09149908A - Living body prosthesis member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To have large binding force with bone cement and prevent bone absorption and dislocation from occurring by providing cement basins connected by a connecting groove so as to connect the filled bone cement in a contact surface part with the bone in a prescribed depth. SOLUTION: A sliding part 3 is provided with fixing reinforcement girders 11, 11 which are formed parallel to side faces 16 from a front inclined face 9 to on the way to a rear inclined face 8 so as to be in symmetrical positions, and cement basins 12 of 1mm-3mm in depth which have U-grooved shapes in a plan view and are formed in such a state as surrounding these girders 11, 11. On the other hand, the cement basins 12 which are formed in a horizontal face 7, a rear inclined face 8, and a front inclined face of the sliding part 3 and integrated therewith are formed in the front wall 1 and rear walls 2, 2 respectively. In a tighbone component (F), the grooved cement basins 12 are so formed in a contact surface with the that that respective filled bone cements are connected by a connection groove in a prescirbed depth. This constitution can stably hold fixing between the bone and the reinforcing member with large binding force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bioprosthesis member that replaces part of human bones or joints whose function is deteriorated or lost due to diseases such as osteoarthritis and pain is increased. is there.

[0002]

2. Description of the Related Art Conventionally, when various members constituting an artificial hip joint or an artificial knee joint are installed on a bone, in order to secure fixability in the early postoperative period and to obtain permanent fixability, A method of fixing a so-called bone cement, which is relatively safe for the living body, between the bone and the prosthesis member has been used.

As a method of reinforcing the binding force of such bone cement, a concave or groove-shaped cement reservoir is provided on the surface of the prosthesis member, and at the cement reservoir portion,
It has been practiced to secure a certain thickness or more of cement and to secure the fixation.

FIG. 3 shows a femoral component F constituting an artificial knee joint as an example of such a conventional bioprosthetic member. This femoral component F is composed of a plate-shaped front wall 1, two left and right rear walls 2, 2 and a sliding portion 3 which connects these and has a substantially arc shape. And the outer surface of the posterior wall 2 has a smooth curved surface similar to the joint sliding surface in the normal state of the femur to be replaced,
In addition, an intercondylar slit 4 is formed at a position that interferes with the attachment part of the anterior and posterior cruciate ligament located posterior to the femur, and divides the two posterior walls 2 and the sliding part at the center. There is.

A flat surface having three different directions is provided inside the sliding portion 3, that is, a horizontal surface 7 in the middle, and a pair of back and front walls 2 and 1 on both sides thereof. Slopes (referred to as a rear slope 8 and a front slope 9, respectively) are provided.

Further, the sliding portion 3 is provided with beams 11 and 11 for fixing and strengthening which are parallel to the side surface 16 at the left and right symmetrical positions from the rear slope 8 to the middle of the front slope 9, and the outside thereof. And on the front side, three groove-shaped cement reservoirs 12, 12, 12 partitioned by embankment-like partitions are formed, and on the other hand, on the inner side surfaces 5, 6 of the front wall 1 and the rear walls 2, 2. Had a groove-shaped cement reservoir 12 formed independently of each other.

[0007]

However, the above-mentioned prior art has the following problems. That is, since each component of the cement pool formed on the joint surface with the bone was partitioned like a bank, a slight difference occurs in the way of transmitting the bonding force and stress between the partition part and the cement pool part. Due to this difference, separation of the bone cement and the prosthesis member starts at the partitioning portion, and this progresses to another portion, weakening the bonding force.

[0008] When such a situation occurs, micro-movement of the prosthesis member or partial concentration of stress may occur, which may lead to serious situations such as bone resorption and displacement of the prosthesis member.

[0009]

SUMMARY OF THE INVENTION In view of the above problems of the prior art, the present invention provides a safe bioprosthesis member that has a large bonding force with bone cement, is stable, and does not cause bone resorption or displacement of the prosthesis member. It is provided.

[0010]

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a bioprosthesis member having a cement pool at the joint surface with bone, without providing a partition between the components of the cement pool. Each filled bone cement is 1mm deep
A cement puddle connected by continuous grooves was formed so as to be connected by ~ 3 mm.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

[0012]

Embodiment 1 FIGS. 1 (a), 1 (b) and 1 (c) are a plan view, a front view and a side view of a femoral component F constituting an artificial knee joint as a bioprosthetic member according to this embodiment. As shown in the figure, this femoral component F is composed of a plate-shaped front wall 1, two right and left rear walls 2, 2 and a sliding portion 3 which connects these and has a substantially arc shape.

The outer surfaces of the anterior wall 1, the sliding portion 3 and the posterior wall 2 of the femoral component F have smooth curved surfaces which approximate the joint sliding surface of the femur to be replaced in the normal state.
An intercondylar slit 4 that divides the two posterior walls 2 and 2 and a part of the sliding portion 3 at the center is formed at a position that interferes with the attachment part of the anterior and posterior cruciate ligaments located posterior to the femur. ing.

As shown in FIG. 1 (a), the lateral surface 16 of the femoral component F is inclined toward the center from the front side to the rear side by 10 ° and 5 °, respectively, from the front side to the rear side.

Further, as shown in FIG. 1 (c), the inner surfaces 5 and 6 of the front wall 1 and the rear wall 2 of the femoral component F which face each other are flat surfaces, and each of them is 3 ° in the vertical direction. Leaning. Further, a flat surface having three different directions is formed inside the sliding portion 3, that is, a horizontal surface 7 is formed in the middle, and a pair of rear surfaces 2 and 1 are formed on both sides of the horizontal surface 7. Slopes (referred to as a rear slope 8 and a front slope 9 respectively) are provided.

Further, in the sliding portion 3, beams 11 and 11 for fixing and strengthening are formed at left and right symmetrical positions in parallel with the side surface 16 from the front slope 9 to the middle of the rear slope 8.
Cement reservoir 12 with a depth of 1 mm to 3 mm surrounding the
Are formed in a groove shape and in a U-shape in a plan view [looks like an inverted U-shape in FIG. 1 (b)]. On the other hand, the front wall 1 and the rear walls 2 and 2 respectively include The cement reservoir 12 provided on the horizontal surface 7, the rear slope 8, and the front slope 9 of the sliding portion 3 is continuous with the cement reservoir 12 formed integrally therewith.

In the femoral component F thus constructed, the groove-shaped cement reservoirs 12 are not individually partitioned on the joint surface portion with the bone, but the filled bone cements are predetermined. The cement pool that is connected by continuous grooves is formed so as to connect with the depth, and the load on the partition and the portion where the bone cement is filled, as in the case where each component of the cement pool 12 is partitioned individually. Since there is no problem of load concentration due to the difference between the two, bone resorption and peeling of bone cement can be avoided, and the fixation of the bone and the prosthesis member can be stably maintained with a large bonding force.

In the femoral component F,
Although the cement reservoir 12 of the sliding portion 3 is U-shaped in plan view, and the cement reservoir 12 is connected at a substantially right angle,
In this way, the cement pool 1 at a large angle of 45 ° or more
When 2 is connected, the fixing force increases dramatically.

The cement reservoir 12 has a depth of 1
If it is less than mm, the amount of cement is small and the bonding strength may be insufficient.

On the other hand, the cement pool has a depth of 12 mm of 3 mm.
If it is larger, the volume of the femoral component F becomes smaller and the strength of the member itself may become smaller.

[0021]

[Embodiment 2] FIG. 2 shows a stem S which constitutes an artificial hip joint as a bioprosthetic member according to the present embodiment. The stem S has a tapered columnar neck 31 for mounting a femoral head ball on its upper end. The stem main body 32 has a tapered shape so as to be fixed in the space of the femur bone marrow.

Of these, on the upper surface of the stem body 32,
A concave cement reservoir 33 having a depth of 1 mm to 3 mm and having the same width is formed in a circumferential shape so as to be connected by a continuous groove without partition.

In the stem S thus constructed, the thickness of the bone cement is reliably ensured at the site where the cement reservoir 33 is formed, so that the bonding force between the bone and the stem S is large,
In addition, since each filled bone cement is connected in a predetermined depth without being partitioned in the circumferential direction, there is little variation in load, and therefore, loosening of the bone in the intertrochanteric part of the femur and bone resorption caused thereby It can be effectively prevented.

[0024]

As described above, according to the present invention, in a bioprosthesis member in which a cement pool is provided on the joint surface portion with bone, bone cement is used as a bone cement without partitioning each component of the cement pool. By making the components mutually continuous so as to be fixedly adhered to the surface continuously and by setting the depth thereof to 1 mm to 3 mm, the variation in the fixing force between the prosthesis member and the bone cement is small, and therefore the loosening with the bone and the It has an excellent effect that it is possible to effectively prevent bone resorption.

[Brief description of the drawings]

FIG. 1 shows a femoral component as a bioprosthetic member according to an embodiment of the present invention, (a) is a plan view,
(B) is a front view, (c) is a side view.

FIG. 2 is a perspective view of an artificial hip joint stem as a bioprosthetic member according to another embodiment of the present invention.

FIG. 3 is a plan view of a femoral component as a conventional bioprosthetic member.

[Explanation of symbols]

 F Femoral component S Stem B Patella 1 Anterior wall 2 Posterior wall 3 Sliding part 4 Intercondylar slits 5, 6 Inner surface 7 Horizontal surface 8 Posterior slope 9 Anterior slope 16 Side 11 Beam 12, 33 Cement pool 31 Neck 32 Stem body

Claims (1)

[Claims] 1. A cement reservoir that is connected by continuous grooves so that each filled bone cement is connected at a depth of 1 mm to 3 mm to a joint surface portion with a bone in a bioprosthetic member for replacing a part of a bone or a joint. A bioprosthesis member provided with.