JP2001346800A - Auxiliary block for cutting tibia or the like - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform multiple-type additional cutting. SOLUTION: When a cut plane 12a of a bone is additionally cut to be 2 mm flat, a fixture is inserted into a fixation hole 1a of a plate 1 in the state of putting an inner face 2c of a plate 2 in contact with the cut plane 12a for fixing the plate 1 to the bone and the bone is cut while guiding a cutter with a guide slit is. When the bone is additionally cut to be 3 mm flat, the cutter is guided with a guide slit 1t. When the bone is additionally cut at a backward tilting angle of 3 deg., the inner face 1c of the plate 1 is put in contact with the cut plane 12a for fixing the plate 2 to the front face of the bone and cutting is performed while guiding the cutter with the guide slit 2s or 2t. This cutting auxiliary block A, which is adaptable for four-type additional cutting, requires lower cost without the need for troublesome management.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auxiliary cutting block used as a guide for a cutter when additionally cutting a tibia or the like.

[0002]

2. Description of the Related Art In a total knee arthroplasty, as shown in FIG. 7, joints of a femur 11 and a tibia 12 are cut, and a femoral component 14 and a tibial component 15 are provided at the cut portions. Attaching is done.
In this case, the femoral component 11 and the tibia component 12 are set using a dedicated set tool so that the selected femoral component 14 and tibial component 15 function properly as a patient's artificial knee joint.
It is often necessary to add an osteotomy for various reasons.

[0003] In such a case, the additional cutting of the bone has been performed by the above-mentioned dedicated setting tool or re-resection tool.

By the way, taking the tibia 12 as an example, the additional cutting mode of the cutting surface 12a to which the tibial component 15 is attached is not only the size of the up-and-down width, but also the flat state in which the patient is horizontal in the upright state, There are various states such as a backward inclined state, a varus state or an everted state inclined inward or outward.

[0005]

However, in both the conventional setting tool and the re-cutting tool, the number of correction steps for additional cutting is one.
Because it is inflexible and inflexible, it is necessary to prepare various kinds of tools to cope with various situations, which is cumbersome to manage and uneconomical.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide an auxiliary cutting block for a tibia or the like which can cope with at least two types of additional cuttings. .

[0007]

In order to achieve the above object, according to the first aspect of the present invention, a plurality of plates having a fixing hole and having a guide slit formed in one end in a width direction are provided. The end portion was connected to another plate at a right angle to form a cutting space to be integrally provided.

In this means, the inner surface of one plate is brought into contact with the cut surface of the bone, and the other plate connected at right angles to the plate is fixed to the bone by using a fixing hole, The cutter is guided by the guide slits of the fixing plate to cut the bone.
Since the number of connected plates is at least two, the main cutting auxiliary block has at least two guide slits.

[0009] In the auxiliary block for cutting a tibia or the like according to the first aspect, a plurality of guide slits can be formed in one or more plate bodies in parallel with each other (claim 2). According to this configuration, the main cutting auxiliary block has at least three guide slits.

[0010] In the cutting auxiliary block for tibia or the like according to the first or second aspect, it is preferable that the state of formation of the guide slit with respect to the reference surface in contact with the already cut surface of the bone is different between the plates. . With this configuration, it is possible to support the same number of additional cutting methods as the number of plate bodies.

[0011]

Embodiments of the present invention will be described with reference to the accompanying drawings. 1 to 4 show an embodiment of an auxiliary block for cutting a tibia or the like according to the present invention. This cutting auxiliary block A has a plurality of (six in the figure) fixing holes 1.
a and a plate body 1 having two guide slits 1s and 1t;
A plurality (six in the same) of fixing holes 2a and a plate body 2 having two guide slits 2s, 2t are formed integrally with each other at a right angle to form a cutting space S.

Each guide slit 1s, 1t, 2s, 2t
Is for guiding a cutter (not shown).
In the thick portions 1b, 2b at the connection ends of the two, the same slit width (1.2 in FIG.
mm).

The guide slits 1 s and 1 t are parallel to each other, and when they are used, come into contact with the cut surface 12 a of the bone and serve as a reference surface. ) And in a side view (FIG. 2). In the figure, the amount of additional cutting of the bone of the guide slit 1s (the distance between the inner surface 2c of the plate 2 and the lower surface of the guide slit 1s) is 2 mm, and the guide slit 1t is provided.
Is set to 3 mm.

The guide slits 2s and 2t are parallel to each other, and when they are used, the cut surface 12a of the bone has already been cut.
The plate 2 is made parallel to an inner surface 1c of the plate 1 serving as a reference surface when it is contacted with the plate 2 in a front view (FIG. 4), and the guide slits 2s, 2 in a side view of the plate 2 (FIG. 2).
As the extension of t moves away from the inner surface 2c, the plate 1
Is inclined (rearwardly inclined) away from the inner surface 1c.
Θ of the inclination angle in the width direction of the guide slits 2s and 2t in the figure
Is 3 times, and the minimum additional cutting amount of the guide slit 2s is 2m
m, the minimum additional cutting amount of the guide slit 2t is set to 3 mm.

In the auxiliary block A for cutting a tibia or the like having the above structure, for example, a flat cut surface 12a of a bone is
mm additional cut, the inner surface 2c of the plate 2
The plate 1 is fixed to the bone by inserting a fixing tool (not shown) such as a fixing pin or a fixing screw into the fixing hole 1a of the plate 1 in a state where the plate 1 is correctly contacted with the cut surface 12a.
Guide the cutter in s to cut the bone. When the bone is additionally cut by 3 mm, the cutter is guided by the guide slit 1t.

When the bone is additionally cut at a backward inclination angle of 3 degrees, the inner surface 1c of the plate 1 is brought into contact with the cut surface 12a, and the plate 2 is fixed to the front surface of the bone as described above. The cutter is guided by the guide slits 2s or 2t.

As described above, the main cutting auxiliary block A is
Since it is possible to cope with four types of additional cutting, the management is not bothered and the cost is reduced. In addition, since the inner surface of another plate connected to the used plate is used as a reference plane, it is reasonable.

FIGS. 5 and 6 show another embodiment of the auxiliary cutting block for a tibia or the like according to the present invention. The basic structure of the cutting auxiliary block B is the same as that of the cutting auxiliary block A. The plate body 4 has a plurality of (six in the figure) fixing holes 4a and two guide slits 4s and 4t. (6)
And a plate body 5 having two guide slits 5s and 5t are integrally formed at a right angle by forming a cutting space S (see FIG. 2).

The guide slits 4s, 4t, 5s, 5t guide the cutter, and are provided along the width direction of the plates 4, 5 at the thick portions 4b, 5b at the connecting ends of the plates 4, 5. They are formed with the same slit width (1.2 mm).

The guide slits 4s, 4t are parallel to each other and, when they are used, the cut surface 12a of the bone (FIG. 2).
(See FIG. 5), and is inclined to the right in a front view (FIG. 5) of the plate body 4 with respect to an inner surface 5c of the plate body 5 serving as a reference surface, and guide slits 4s, 4t in a side view of the plate body 4.
Is made parallel to the inner surface 5c of the plate body 5. In the figure, the inclination angle α in the length direction of the guide slits 4s and 4t is 2
The minimum additional cutting amount of the guide slit 4s is set to 2 mm, and the minimum additional cutting amount of the guide slit 4t is set to 3 mm.

The guide slits 5s and 5t are also parallel to each other, and when they are used, the cut surface 12a of the bone has already been cut.
The plate body 5 is inclined leftwardly wide with respect to the inner surface 4c of the plate body 4 serving as a reference surface when it comes into contact with the guide body 5 in a front view (FIG. 6), and the width direction of the guide slits 5s and 5t in a side view of the plate body 5. Are parallel to the inner surface 4c of the plate body 4. In the figure, the inclination angle β in the length direction of the guide slits 5s and 5t is set to 2 degrees, the minimum additional cutting amount of the guide slit 5s is set to 2 mm, and the minimum additional cutting amount of the guide slit 5t is set to 3 mm.

The method of using the auxiliary cutting block B having the above configuration is basically the same as that of the above-described auxiliary cutting block A. When the cutter is guided by the guide slits 4s or 4t, the bone is located at the lower right in FIG. When the cutter is guided by the guide slit 5s or 5t at an angle α, the bone is additionally cut at an angle β to the lower left in FIG. The guide slits 4s, 4t, 5s, 5t
Is usually a varus or valgus cut.

The same effect as the auxiliary cutting block A can be obtained in the auxiliary cutting block B.

Although two guide slits are provided in each of the plates 1, 2, 4, and 5 in FIG.
One or three or more guide slits can be formed, and a plurality of guide slits can be formed without being parallel to each other.

The state of formation of the guide slits with respect to the inner surface of the plate serving as the reference plane, that is, the inclination angles θ, α, β, parallelism (angle 0) and the like are not limited to those shown in the drawings, and it goes without saying that various changes can be made. .

Although the guide slits have the same slit width, one or more guide slits having different slit widths may be provided to enable use of cutters having different wall thicknesses. The plate 1 and the plate 4 or the plate 5 may be combined, or the plate 2 and the plate 4 or the plate 5 may be combined. In some cases, the number of connected plates is 3
It is also possible to make individual pieces.

[0027]

As described above, according to the first aspect of the present invention, it is possible to obtain an auxiliary cutting block for a tibia or the like that can perform two or more types of additional cutting. Therefore, various situations can be dealt with with a small number of cutting auxiliary blocks, so that management and the like become easy and the cost is reduced.

In the auxiliary block for cutting a tibia or the like according to the first aspect, when a plurality of guide slits are formed in one or more plates in parallel with each other, the number of additional cuts increases,
In addition, since a plurality of guide slits having the same additional cutting method are provided side by side, workability is improved.

[0029] In the auxiliary block for cutting a tibia or the like according to the first or second aspect, when the formation state of the guide slits with respect to the reference plane that is in contact with the already cut surface of the bone is made different from each other between the plates, two or more types are used. An additional cutting method can be easily selected.

[Brief description of the drawings]

FIG. 1 is an external view showing an embodiment of an auxiliary block for cutting a tibia or the like according to the present invention.

FIG. 2 is a sectional view of the auxiliary cutting block of FIG. 1;

FIG. 3 is a front view of the cutting auxiliary block of FIG. 1;

FIG. 4 is a front view in which another plate body of the auxiliary cutting block of FIG. 1 is put forward;

FIG. 5 is a front view showing another embodiment of an auxiliary cutting block for a tibia or the like according to the present invention.

FIG. 6 is a front view showing another plate body of the auxiliary cutting block of FIG.

FIG. 7 is a view showing an artificial knee joint.

[Explanation of symbols]

A, B Auxiliary block for cutting 1, 2, 4, 5
Plate 1a, 2a, 4a, 5a Fixing hole 1b, 2b, 4
b, 5b Thick portion 1c, 2c, 4c, 5c Inner surface (reference surface) 1s, 1t, 2s, 2t, 4s, 4t, 5s, 5t Guide slit S Cutting space 12a Existing cut surface

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[Procedure amendment]

[Submission date] June 22, 2000 (2000.6.2)
2)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0002

[Correction method] Change

[Correction contents]

[0002]

BACKGROUND OF THE INVENTION knee Takashi Seki replacement surgery, as shown in FIG. 7, the femoral Konponento 14 and tibial component 15 to the cut point joint portion of the femur 11 and the tibia 12 by cutting each Attaching is done.
In this case, as the femoral component 14 and the tibial component 15 that has been selected to function properly as an artificial knee function nodes of patients, the femur 11 in a dedicated set tool and the tibia 12
It is often necessary to add an osteotomy for various reasons.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Fig. 7

[Correction method] Change

[Correction contents]

FIG. 7 is a diagram illustrating an artificial knee function clause.

Claims (3)

[Claims] 1. A plurality of plates having a fixing hole and having a guide slit formed in one end in a width direction are connected to the other end at right angles to another plate to form a cutting space and be integrated. An auxiliary block for cutting a tibia or the like, which is provided. 2. A plurality of guide slits are parallel to each other.
2. The auxiliary block for cutting a tibia or the like according to claim 1, wherein the auxiliary block is formed on the plate. 3. The assisting block for cutting a tibia or the like according to claim 1, wherein formation states of the guide slits with respect to a reference surface in contact with the already cut surface of the bone are different from each other between the plates.