WO2020202521A1

WO2020202521A1 - Bone fixation plate

Info

Publication number: WO2020202521A1
Application number: PCT/JP2019/014918
Authority: WO
Inventors: 真樹新; 宏一黒田
Original assignee: オリンパステルモバイオマテリアル株式会社
Priority date: 2019-04-04
Filing date: 2019-04-04
Publication date: 2020-10-08
Also published as: JP7284805B2; TWI779186B; JPWO2020202521A1; TW202037338A

Abstract

This bone fixation plate (1) is provided with: a first region (1A) which is situated on one end side and has one or more insertion holes (2); a second region (1B) which is situated on the other end side and has two or more insertion holes (2); a first thin region (4) which is disposed between the first and second regions (1A, 1B) and is thinner than each of rim parts (3) respectively surrounding the insertion holes (2); and second thin regions (5) which are disposed between the insertion holes (2) in the second region (1B) and are thinner than the rim parts (3), wherein the first thin region (4) has a longitudinal axis dimension different from that of each of the second thin regions (5), and the first thin region (4) has a cross section that is uniform in the longitudinal axis direction.

Description

Bone fixation plate

The present invention relates to a bone fixation plate.

Conventionally, plates for fracture treatment are known (see, for example, Patent Document 1). The plate is placed on the surface of the bone so as to straddle the fracture site and is fixed to the bone by a screw.

JP 2015-167779

It is desirable that the shape of the plate for fracture treatment matches the bone shape of the application site. Since the bone shape differs from patient to patient, it is necessary for the surgeon to confirm the bone shape of the patient and adjust the shape of the plate so as to match the bone shape during the operation. However, it is not easy to bend a plate having the strength required to support the bone to fit the bone shape of each patient.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a bone fixation plate that can be easily adjusted to a shape that matches the bone shape.

One aspect of the present invention is a bone fixing plate composed of a plate-shaped member having a longitudinal axis and having a plurality of insertion holes into which screws are inserted, and one end side having one or more of the insertion holes. A first thin wall provided between one region, a second region on the other end side having two or more insertion holes, and the first region and the second region, and thinner than the edge portion surrounding the insertion hole. A second thin-walled region provided between the two or more insertion holes of the second region and thinner than the edge portion is provided, and the dimension of the first thin-walled region in the longitudinal axis direction is the first. 2 A bone fixing plate in which the cross section of the first thin-walled region is uniform in the longitudinal axis direction, unlike the dimension of the thin-walled region in the longitudinal axis direction.

According to the present invention, there is an effect that the shape can be easily adjusted to match the bone shape.

It is a top view of the bone fixation plate which concerns on one Embodiment of this invention. It is a side view of the bone fixation plate of FIG. It is a vertical cross-sectional view of the bone fixation plate of FIG. 1 along the line I-I. It is an enlarged view of the region III including the insertion hole of FIG. It is a cross-sectional view of the bone fixation plate of FIG. 1 in line II-II. It is a figure which shows one use example of the bone fixation plate of FIG. It is a top view of the bone fixation plate which concerns on other embodiment of this invention. It is a top view of the bone fixation plate which concerns on other embodiment of this invention.

The bone fixation plate 1 according to the embodiment of the present invention will be described below with reference to the drawings.
As shown in FIGS. 1 and 2, the bone fixation plate 1 is a plate-shaped member having a linear longitudinal axis A. The bone fixation plate 1 is T-shaped in a plan view in the thickness direction, and has a first region 1A on one end side extending linearly along a short axis B orthogonal to the longitudinal axis A and a longitudinal axis. It has a second region 1B on the other end side extending linearly along A.
In the following description, the length direction is the direction parallel to the longitudinal axis A, the width direction is the direction parallel to the minor axis B, and the thickness direction is orthogonal to the longitudinal axis A and the minor axis B. It is the plate thickness direction. Further, the length, width, and thickness are dimensions in the length direction, the width direction, and the thickness direction, respectively.

The first region 1A protrudes on both sides in the width direction from the second region 1B, and the width of the first region 1A is larger than the width of the second region 1B. Further, the length of the first region 1A is smaller than the length of the second region 1B.

As shown in FIGS. 1 and 3, the bone fixation plate 1 is provided with a plurality of insertion holes 2 penetrating in the thickness direction, and each insertion hole 2 is surrounded by an annular edge portion 3. A screw S for fixing the bone fixing plate 1 to the bone is inserted into each insertion hole 2 (see FIG. 6). The screw S is a locking screw having a thread on the outer peripheral surface of the head. As shown in FIG. 4, the insertion hole 2 is a female screw to which the head of the screw S is fastened.

The first region 1A has one or more insertion holes 2, and the second region 1B has two or more insertion holes 2. In the reference drawing, the first region 1A has two insertion holes 2 and the second region 1B has three insertion holes 2. The number of insertion holes 2 in the first region 1A may be only one or three or more. The number of insertion holes 2 in the second region 1B may be only two or four or more.
The two insertion holes 2 of the first region 1A are arranged in the width direction and are offset from the longitudinal axis A in the width direction in opposite directions. All the insertion holes 2 in the second region 1B are arranged in a row on the longitudinal axis A at intervals from each other in the length direction.

The bone fixation plate 1 has a first thin-walled region 4 and a second thin-walled region 5.
The first thin-walled region 4 is provided between the first region 1A and the second region 1B. One end of the first thin-walled region 4 is connected to the edge 3 of the two insertion holes 2 of the first region 1A, and the other end of the first thin-walled region 4 is the insertion hole 2 on the most end side of the second region 1B. It is connected to the edge 3.
The second thin-walled region 5 is provided between the insertion holes 2 of the second region 1B, and both ends of each of the second thin-walled regions 5 are connected to the edge portion 3.
The length of the first thin-walled region 4 is larger than the length of the second thin-walled region 5.

As shown in FIGS. 2 and 3, the thickness of each of the first thin-walled region 4 and the second thin-walled region 5 is smaller than the thickness of the edge portion 3, and the thickness of each thin-

walled region

4 and 5 and the edge portion 3 A step in the thickness direction is formed between them. Therefore, each of the first thin-walled region 4 and the second thin-walled region 5 has lower rigidity than the edge portion 3, and the rigidity is discontinuous between each of the thin-

walled regions

4 and 5 and the edge portion 3. It's changing. In the drawings to be referred to, both ends of the edge portion 3 in the width direction are chamfered, and the thickness of the edge portion 3 means the thickness of the portion excluding the chamfered portion and the groove 9 (described later).
Further, the width of each of the first thin-walled region 4 and the second thin-walled region 5 is smaller than the width of the edge portion 3 of the second thin-walled region 1B.
Further, the cross section of the first thin-walled region 4 orthogonal to the longitudinal axis A is uniform in the substantially overall length in the length direction, and therefore the rigidity of the first thin-walled region 4 is constant in the length direction.

On the side surface of one end of the bone fixing plate 1, a recess 6 is formed in which a recessed guide pin P is fitted in the radial direction inward in the longitudinal direction. By applying the recess 6 to the guide pin P inserted into the bone, the bone fixing plate 1 can be temporarily positioned with respect to the guide pin P and the bone.
At least one of the first region 1A and the second region 1B may be provided with a guide hole 11 penetrating in the thickness direction into which the guide pin P is inserted.

The bone fixation plate 1 has a pair of

surfaces

7 and 8 facing each other in the thickness direction. As shown in FIGS. 5 and 6, one surface 7 is an inner surface arranged on the bone side and the other surface 8 is an outer surface arranged on the side opposite to the bone. As shown in FIG. 5, a groove 9 extending along the longitudinal axis A and recessing in the thickness direction is formed on the inner side surface 7. When the bone fixation plate 1 is placed on the curved surface of the bone X, the inner surface 7 contacts the bone X at both ends of the groove 9 and a gap is secured between the inner surface of the groove 9 and the surface of the bone X. Will be done.

Next, an example of how to use the bone fixation plate 1 will be described.
The bone fixation plate 1 is used for osteotomy or fracture treatment. FIG. 6 shows an example of using the bone fixation plate 1 for high tibial osteotomy (HTO).
In the HTO, two incisions are formed in a direction inclined with respect to the longitudinal axis of tibia X from the elevated lateral surface of tibia X to the medial side, and bone fragments between the two incisions are removed using a predetermined instrument. .. In this state, the hinge portion H is formed on the inner surface side of the excision site of the bone fragment, and the epiphysis X1 above the excision site can swing with respect to the diaphysis X2 about the hinge portion H.

Next, the guide pin P, which serves as a guide for the position of the bone fixation plate 1 with respect to the tibia X, is inserted into the epiphysis X1 from the inside. Next, the first region 1A and the second region 1B are arranged on the inner side surfaces of the epiphysis X1 and the diaphysis X2, respectively, and the bone fixation plate 1 is abutted against the guide pin P in the recess 6 to provide the bone fixation plate 1. Positioning with respect to epiphysis X1 and diaphysis X2. The position of the guide pin P with respect to the epiphysis X1 is set so that the first thin-walled region 4 is arranged at the hinge portion H. In this state, the difference between the shape of the bone fixation plate 1 and the shape of the tibia X is confirmed.

Next, the bone fixing plate 1 is curved in the first thin-walled region 4 and the second thin-walled region 5, so that the shape of the bone fixing plate 1 is adjusted to match the shape of the inner surface of the tibia X. For example, a dedicated bender is used for bending the bone fixing plate 1.
Next, again, the first region 1A and the second region 1B are arranged on the inner side surfaces of the epiphysis X1 and the diaphysis X2, respectively, and the bone fixing plate 1 is abutted against the guide pin P in the recess 6 to fix the bone fixing plate. 1 is positioned with respect to the epiphysis X1 and the diaphysis X2.

Next, the screw S is screwed into the epiphysis X1 via the insertion hole 2 of the first region 1A, and the screw S is screwed into the diaphysis X2 via the insertion hole 2 of the second region 1B. Each screw S is screwed into the bones X1 and X2 until the head is fastened into the insertion hole 2. The epiphysis X1 and the epiphysis plate 1 fixed to the epiphysis X2 on both the upper and lower sides of the hinge portion H restrict the swing of the epiphysis X1 with respect to the diaphysis X2 around the epiphysis H, and the position of the epiphysis X1 with respect to the diaphysis X2. Is stable.

Next, a wedge-shaped artificial bone C is inserted into the gap between the dilated cut surfaces Y, and another bone fixation plate 30 is placed on the outer surfaces of the epiphysis X1 and the diaphysis X2 so as to straddle the cut surface Y. Then, the other bone fixing plate 30 is fixed to the epiphysis X1 and the diaphysis X2 by the screw S.

In order to obtain a high fixing force of the bone fixing plate 1 to the bone, a high fixing force between the head of the screw S and the insertion hole 2 is required. For that purpose, the edge 3 of the insertion hole 2 needs to have high strength. Further, since the deformation and damage of the insertion hole 2 causes a decrease in the fixing force between the screw S and the insertion hole 2, it is necessary to prevent the deformation and damage of the insertion hole 2.

The bone fixing plate 1 according to the present embodiment is provided with thin-

walled regions

4 and 5 which are thinner and less rigid than the edge portion 3 at a plurality of locations in the length direction. Therefore, the bone fixing plate 1 can be selectively and easily deformed in the thin-

walled regions

4 and 5 while preventing the insertion hole 2 from being deformed. Thereby, the shape of the bone fixing plate 1 can be easily adjusted without affecting the fixing force of the bone fixing plate 1 to the bone.

Further, the insertion hole 2 is not required in the portion between the first region 1A and the second region 1B arranged in the hinge portion H. By providing the long first thin-walled region 4 having a uniform cross section in such a portion, the degree of freedom of deformation of the bone fixing plate 1 can be effectively improved. That is, the first thin-walled region 4 can be easily bent or twisted into an arbitrary shape at an arbitrary position in the length direction. Therefore, the bone fixation plate 1 can be easily adjusted to a shape according to the bone shape of each patient.

Further, since the groove 9 is formed on the inner surface 7, the bone fixing plate 1 comes into contact with the bone X at two points in the width direction, and a gap is formed between the surface of the bone X and the inner surface of the groove 9. Secured. As a result, the contact area of the inner side surface 7 with the bone X is reduced, the influence of the bone fixing plate 1 on the blood vessels on the surface of the bone X is reduced, and the position and posture of the bone fixing plate 1 with respect to the bone X are stabilized. be able to.
Further, the recess 6 formed at one end of the bone fixing plate 1 and the guide pin P can be used to easily position the bone fixing plate 1 with respect to the bone X.

Further, by using a locking screw that is fastened to the insertion hole 2 as the screw S, it is possible to prevent the screw S from moving in the direction of coming out of the bone X after fixing the bone fixing plate 1 to the bone X by the screw S. , The fixing force of the bone fixing plate 1 with respect to the bone X can be maintained.
Further, the two insertion holes 2 of the first region 1A arranged at the epiphysis X1 are arranged in the width direction. As a result, the length of the first region 1A can be reduced to the same level as the width of the edge portion 3, and the first region 1A can be firmly fixed to the epiphysis X1 by using two screws S. Such a short first region 1A is particularly suitable for application to the short epiphysis X1.

Although the T-shaped bone fixation plate 1 has been described in the above embodiment, the shape of the bone fixation plate 1 can be changed as appropriate. 7 and 8 show a modified example of the bone fixation plate 1.
The bone fixing plate 10 of FIG. 7 is Y-shaped in a plan view in the thickness direction. Specifically, the first region 10A has a V-shape having two portions inclined with respect to the longitudinal axis A, and protrudes from the second region 10B on both sides in the width direction. The second region 10B is configured in the same manner as the second region 1B. The two insertion holes 2 of the first region 10A are offset from the longitudinal axis A in the width direction and in opposite directions to each other. A thin-walled region 51 similar to the second thin-walled region 5 is provided between each insertion hole 2 of the first region 1A and the first thin-walled region 4.

The bone fixing plate 20 of FIG. 8 is I-shaped in a plan view in the thickness direction. Specifically, the first region 20A and the second region 20B extend linearly along the longitudinal axis A, and all the insertion holes 2 of the first region 20A and the second region 20B are aligned along the longitudinal axis A. It is arranged in. A thin-walled region 52 similar to the second thin-walled region 5 is provided between the two insertion holes 2 of the first region 20A.
The

bone fixing plates

10 and 20 also have a recess 6 formed on one end side surface and a groove 9 formed on the inner side surface 7.

The above-mentioned HTO is only an example of how to use the

bone fixation plates

1, 10 and 20, and the

bone fixation plates

1, 10 and 20 can be used for other parts and other uses. The shape and dimensions of the

bone fixation plates

1, 10 and 20 and the number of insertion holes 2 can be changed according to the application site and application.

For example, the

bone fixation plates

1, 10 and 20 may be fixed to the lateral surface of the tibia X in the same manner as the other bone fixation plates 30. Alternatively, the

bone fixation plates

1, 10 and 20 may be applied to bones at other sites such as the femur or clavicle.

Bone fixation plates

1, 10 and 20 may be used for the treatment of bone fractures at any site.
Depending on the application site and application, the length of the first thin-walled region 4 may be smaller than the length of the second thin-walled region 5.
Further, in FIGS. 1 and 7, the two insertion holes 2 of the

first regions

1A and 10A are offset on both sides in the width direction from the longitudinal axis A, but the arrangement of the insertion holes 2 in the first region is the same. Without limitation, a part or all of the insertion hole 2 in the first region may be offset to both sides or one side in the width direction from the longitudinal axis A. The outline shape of the bone fixation plate in the plan view may be changed according to the arrangement of the insertion holes 2 in the first region. For example, in the case of an L-shaped bone fixing plate in a plan view, the insertion hole 2 in the first region may be offset to one side in the width direction from the longitudinal axis A.

1,10,20

Bone fixation plates

1A, 10A,

20A 1st region

1B, 10B, 20B 2nd region 2 Insertion hole 3 Edge 4 1st thin region 5 2nd thin region 6 Recess 7 Inner side surface 8 Outer side surface 9 Groove A Longitudinal axis B Short axis X Tibia X1 Epiphysis X2 Diaphysis Y Cut surface H Hinge part S Screw P Guide pin C Artificial bone

Claims

A bone fixation plate consisting of a plate-shaped member having a longitudinal axis and having a plurality of insertion holes into which screws are inserted.
A first region on one end side having one or more of the insertion holes,
A second region on the other end side having two or more of the insertion holes,
A first thin-walled region provided between the first region and the second region and thinner than the edge surrounding the insertion hole,
A second thin-walled region provided between the two or more insertion holes in the second region and thinner than the edge portion,
With
The dimension of the first thin-walled region in the longitudinal axis direction is different from the dimension of the second thin-walled region in the longitudinal axis direction.
A bone fixation plate having a uniform cross section of the first thin-walled region in the longitudinal axis direction.
The bone fixation plate according to claim 1, wherein all the insertion holes in the second region are arranged in a row on the longitudinal axis.
The bone fixation plate according to claim 2, wherein the insertion hole in the first region is offset from the longitudinal axis in the width direction orthogonal to the longitudinal axis.
The bone fixation plate according to claim 2, wherein all the insertion holes in the first region are arranged in a row on the longitudinal axis.
The first region is located at the epiphysis and
The bone fixation plate according to any one of claims 1 to 4, wherein the second region is arranged on the diaphysis.
The bone fixing plate according to any one of claims 1 to 5, wherein a groove extending along the longitudinal axis is formed on one of two surfaces facing each other in the plate thickness direction.
The bone fixing plate according to any one of claims 1 to 6, wherein a recess is formed on the side surface of the one end inward in the longitudinal axis direction and a recess in which the guide pin fits in the radial direction is formed.