Guide block for radial fixation plate

Abstract

This guide block 5 for a radius-fixing plate is placed on a radius-fixing plate 2 and guides a fixing screw 4 for fixing the radius-fixing plate to a radius 3, the guide block comprising: a distal part 5x that can be placed on a distal region 2a of the radius-fixing plate and has a screw guide hole 5d, for the fixing screw, communicating with a screw insertion hole 2d of the radius-fixing plate 2d; and a proximal part 5y that can be placed on a proximal region 2b of the radius-fixing plate and has a screw guide hole 5d, for the fixing screw, communicating with the screw insertion hole 2d of the radius-fixing plate, wherein the distal part and the proximal part are disposed in a relatively movable manner.

Description

[Technical field]

[0001] The present invention relates to a guide block for a radial fixation plate, which guides a fixation screw that rotates to fix the radial fixation plate to a radius. [Background technology]

[0002] When the radius is fractured, a radial fixation plate that spans the fractured portion to fix the radius is known as an alternative to a splint (i.e., a splint) or a plaster or FRP cast in order to fix the fractured portion of the radius.

[0003] When the radial fixation plate is fixed to the radius, a plurality of fixation screws are fastened to the radius.

[0004] Conventionally, a thin metal plate such as titanium or its alloy, which is strong, lightweight, and highly biosafe, has been used as a radius fixation plate.

[0005] However, metal plates do not allow X-rays to pass through, making it difficult to grasp the condition of the fractured area covered by the radius fixation plate.

[0006] Therefore, in recent years, thin resin radius fixation plates have been developed instead of metal ones (see, for example, Patent Document 1).

[0007] [Patent Document 1] Patent Publication No. 4988693 DISCLOSURE OF THEINVENTION

[0008] However, when such a resin radius fixation plate is fixed to the radius with a fixing screw, the radial fixation plate is thin, and therefore the fixing screw cannot be inserted in a specified direction (e.g., perpendicular to the plate surface) into each female screw provided in the radius fixation plate, which may lead to damage to the female screw. Also, since the insertion direction of the fixing screw into the radius fixation plate is designed in advance to match the shape of the radius, if the fixing screw is inserted in a different direction, even if the female screw is not damaged, it may cause a hindrance to the function of the radius fixation plate.

[0009] In order to prevent such damage to the female thread and to enable the plate to function as a radius fixation plate, a guide block has been placed on the distal region of the radius fixation plate so that the fixation screw can be inserted in a specified direction using the guide block.

[0010] In recent years, there has been a need to more reliably screw the female threads that fix the plate to the radius into the radius through a cross-threading process, and in order to prevent damage to the female threads and to enable the radius fixation plate to perform its function, there has been a demand for a screw tightening guide not only in the distal region of the radius fixation plate, but also in the proximal region of the radius fixation plate.

[0011] Therefore, the object of the present invention is to provide a guide block for a radius fixation plate which meets the above-mentioned demands and can easily and reliably guide fixation screws when tightening them, even in the proximal region of a plastic radius fixation plate.

[0012] In order to achieve the above object, the present invention is configured as follows.

[0013] According to one aspect of the present invention, there is provided a guide block for a radial fixation plate, which is placed on a radial fixation plate to guide a fixation screw for fixing the radial fixation plate to a radius, the guide block comprising: a distal portion that can be mounted on a distal region of the radial fixation plate and has a screw guide hole for the fixation screw that communicates with a screw insertion hole of the radial fixation plate; a proximal portion that can be placed on a proximal region of the radial fixation plate and has a screw guide hole for the fixation screw that communicates with a screw insertion hole of the radial fixation plate; The distal portion and the proximal portion are arranged to be movable relative to each other. Along with, The distal end of the proximal portion is provided with a connecting portion that is disposed between the distal end and the proximal portion and connects the distal end and the proximal portion to each other so as to be relatively flexible. A guide block for a radial fixation plate is provided.

[0014] According to the above aspect of the present invention, the screw guide holes can easily and reliably guide the fixation screws when tightening not only in the distal region of the radius fixation plate but also in the proximal region. Furthermore, even when the proximal region of the radius fixation plate is bent along the radius relative to the distal region of the radius fixation plate for fixing, the proximal portion of the guide block can be made movable relative to the distal portion, for example, bent. Therefore, the guide block can be placed so as to be aligned with the bent radius fixation plate, and the screw guide holes can more reliably guide the fixation screws when tightening in both the distal and proximal regions. [Brief description of the drawings]

[0015] These and other objects and features of the present invention will become apparent from the following description of the preferred embodiments taken in conjunction with the accompanying drawings, in which: [Figure 1] FIG. 1 is a perspective view showing a state in which the radial fixation plate is bent and fixed to the radius by a fixing screw while using a guide block for a radial fixation plate according to an embodiment of the present invention, and then the guide block is removed from the radial fixation plate; [Figure 2A] FIG. 1 is a partially perspective explanatory view showing a state in which a fixing screw is inserted into a guide block and a radial fixation plate by a tool for fixing screws of a radial fixation plate and fastening is started in an embodiment of the present invention; [Figure 2B] FIG. 1 is a partially perspective explanatory diagram showing the state where the fixation screw is nearly completed when the fixation screw is inserted through the guide block and the radial fixation plate using a tool for fixing the radial fixation plate screws. [Figure 2C]FIG. 1 is a partially perspective explanatory diagram showing the state in which the center cylinder is in contact with the guide block and in the idling position when the fixing screw is inserted through the guide block and the radial fixation plate by the radial fixation plate fixing screw tool and tightened. [Figure 3A] FIG. 2 is a plan view of a radial fixation plate guide block to be placed on the radial fixation plate; [Figure 3B] Bottom view of the guide block of FIG. 3A [Figure 3C] FIG. 3B is a side view of the guide block of FIG. [Figure 4A] FIG. 3B is an explanatory diagram of two locking protrusions of the guide block of FIG. 3A; [Figure 4B] FIG. 4B is an enlarged cross-sectional view of one locking protrusion of the guide block of FIG. [Figure 5A] FIG. 3B is a plan view showing the guide block of FIG. 3A placed and held on a resin radial bone fixing plate; [Figure 5B] FIG. 5B is an explanatory diagram showing the position of the metal wire obtained by X-ray photography in the state of FIG. 5A and the position of the radial fixation plate for comparison. [Figure 5C] A plan view of the guide block placed and held on the resin radial fixation plate on the radius. [Figure 5D] FIG. 5C is an explanatory diagram showing the position of the metal wire on the radius obtained by X-ray photography in the state of FIG. 5C and the position of the radial fixation plate for comparison. [Figure 5E] FIG. 1 is a perspective view of the proximal end of a guide block placed and held on a resin radial bone fixing plate on a radius bone, viewed from diagonally above. [Figure 5F] FIG. 1 is a perspective view of the vicinity of a connecting portion of a guide block placed and held on a resin radial bone fixing plate on a radius bone, as viewed from an obliquely lower side. [Figure 5G] FIG. 1 is a perspective view of the vicinity of a connecting portion of a guide block placed and held on a resin radial bone fixing plate on a radius bone, as viewed from diagonally above. [Figure 6A] FIG. 13 is a plan view of a modified example in which the wire arrangement is different, in which the guide block is placed and held on a resin radial bone fixation plate. [Figure 6B]FIG. 6B is an explanatory diagram showing the position of the metal wire obtained by X-ray photography in the state of FIG. 6A in the modified example of FIG. 6A and the position of the radial fixation plate for comparison. [Figure 6C] FIG. 6B is an explanatory diagram showing the position of the metal wire obtained by X-ray photography after placing the metal wire on the radius in the state of FIG. 6A in the modified example of FIG. 6A, and the position of the radius fixation plate for comparison; [Figure 6D] FIG. 6C is an explanatory diagram showing the appropriate line for the radius at the distal end of the radial fixation plate, which is clinically recommended. [Figure 6E] FIG. 6D is a close-up of a portion of FIG. 6D as viewed perpendicular to the surface of the distal portion of the radial fixation plate. [Figure 7A] FIG. 13 is a perspective view of a modified example of the arrangement of the distal portion and the proximal portion, in which the guide block is placed and held on a resin radial bone fixing plate; [Figure 7B] FIG. 7B is a plan view showing a state in which the guide block is placed and held on a resin radial bone fixing plate in the modified example of FIG. 7A; [Figure 7C] FIG. 7B is a side view of the modified example of FIG. 7A in which the guide block is placed and held on a resin radial bone fixing plate; [Figure 8A] FIG. 13 is a perspective view of a modified example of the connecting portion between the distal portion and the proximal portion, in which the guide block is placed and held on a resin radial bone fixing plate; [Figure 8B] FIG. 8B is a side view of the modified example of FIG. 8A in which the guide block is placed and held on a resin radial bone fixing plate; [Figure 8C] FIG. 8B is an enlarged perspective view of the vicinity of the connecting portion in the modified example of FIG. 8A; [Figure 9A] FIG. 13 is a perspective view of a state in which a guide block is placed and held on a resin radial bone fixing plate in another modified example of the connecting portion between the distal portion and the proximal portion. [Figure 9B] FIG. 9B is a side view of the modified example of FIG. 9A in which the guide block is placed and held on a resin radial bone fixing plate; [Figure 9C] FIG. 9B is an enlarged perspective view of the vicinity of the connecting portion in the modified example of FIG. 9A; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Before continuing with the description of the present invention, reference is made to the accompanying drawings in which like parts are designated by like reference numerals.

[0017] A guide block 5 for a radius fixing plate according to an embodiment of the present invention is a member that guides a fixing screw 4 when a radius fixing plate 2 is fixed to a radius 3 with the fixing screw 4, as shown in Figs. 1 to 2C.

[0018] First, the radius fixing plate 2 and the fixing screw 4 will be described, and then the guide block 5 will be described.

[0019] As shown in Figs. 1 to 2C, the radius fixation plate 2 is fixed to the radius 3 across the fractured portion 3a of the radius 3. At this time, in order to facilitate the screw tightening operation of rotating the fixation screw 4 with the tool 1 for fixing screws of a radius fixation plate, a guide block 5 as shown in Figs. 3A to 3C is placed on the radius fixation plate 2. After being placed in this manner, the guide block 5 is placed on the radius 3, and the screw tightening operation is performed on the radius 3 while guiding the screw guide hole 5d of the guide block 5 in cooperation with a pilot hole previously formed in the radius 3 so that the fixation screw 4 can be inserted in a specified direction. After the radius fixation plate 2 is fixed to the radius 3, the guide block 5 is removed from the radius fixation plate 2.

[0020] 1, the fractured portion 3a of the radius 3 is divided into a radius body 3b and a fractured fragment 3c by the fractured portion 3a. The radius body 3b and the fractured fragment 3c may be completely separated or may be partially connected.

[0021] The radius fixation plate 2 is placed on the radius 3 so that the fractured fragment 3c is fixed in a state in which it is normally connected to the radius body 3b.

[0022] The radial fixation plate 2 is made of, for example, a synthetic resin, such as a thermoplastic resin or a composite material thereof. Examples of the thermoplastic resin include PEEK (polyether ether ketone) and polyetherimide.

[0023] As an example, the radius fixation plate 2 is a T-shaped plate member made up of a wide distal region 2a and a proximal region 2b extending from the distal region 2a. In this specification, the "proximal region" refers to a region of the radius fixation plate 2 that is closer to the heart, and the "distal region" refers to a region of the radius fixation plate 2 that is farther from the heart than the proximal region.

[0024] The distal region 2a is fixed to the fracture fragment 3c with a plurality of fixation screws 4, and the proximal region 2b is fixed to the radial body 3b with a plurality of fixation screws 4 so that the radius fixation plate 2 spans the fractured portion 3a and the fracture fragment 3c is normally connected to the radial body 3b.

[0025] The distal region 2a and the proximal region 2b each have a large number of circular screw insertion holes 2d extending axially in the thickness direction of the radius fixation plate 2 or in a direction inclined relative to the thickness direction. If necessary, a fixing screw 4 is inserted into the screw insertion hole 2d and screwed into both a part of the screw insertion hole 2d of the radius fixation plate 2 and the radius 3 to fix the radius fixation plate 2 to the radius 3. As shown in Figs. 2A to 2C, each screw insertion hole 2d is composed of a large-diameter head housing portion 2e and a small-diameter female screw portion 2f that is smaller than the inner diameter of the head housing portion 2e.

[0026] As shown in FIGS. 2A to 2C, the fixing screw 4 to be inserted into the screw insertion hole 2d is made of hard metal, and is composed of a head 4c and a shaft 4a connected to the head 4c.

[0027] The shaft portion 4a has a diameter smaller than the inner diameter of the female thread portion 2f of the screw insertion hole 2d and can pass through the female thread portion 2f. A main screw 4b that self-taps on the radius 3 after passing through the screw insertion hole 2d is formed on the shaft portion 4a.

[0028] As an example, the head 4c has an outer diameter equal to the inner diameter of the female threaded portion 2f, and is accommodated in the head accommodation portion 2e when the screw is fastened. A sub-thread 4d is formed on the outer peripheral surface of the shaft portion side of the head 4c, and is screwed into the female threaded portion 2f of the screw insertion hole 2d. Instead of the sub-thread 4d being screwed into the female threaded portion 2f, the female threaded portion 2f may be formed as a threaded portion without a female thread being formed in advance, and the sub-thread 4d may be screwed into the threaded portion by performing a self-tapping action.

[0029] A hexalobular hole 4j is formed on the top surface of the head 4c, and a screw coupling portion 12c of a rotating shaft portion 12 of the tool 1 described later is coupled thereto, thereby enabling the fixing screw 4 to rotate forward and backward. The hexalobular hole 4j is an example, but it is preferable because the hexalobular hole 4j and the screw coupling portion 12c in the shape of a hexalobular wrench come into contact with each other at the crests and the roots, and do not slip unless both are completely smoothed. In other words, the hexalobular hole 4j has the effect of efficiently transmitting the tightening torque and reducing the risk of damage to the tool or the head of the screw by eliminating stress concentration.

[0030] As shown in Figures 2A to 2C and 3A to 3C, the guide block 5 is placed and held on the radius fixation plate 2, and then placed on the radius 3. When the fixation screw 4 is then rotated with the radius fixation plate fixation screw tool 1 to perform the screw tightening operation, the guide block 5 guides the fixation screw 4 to make it easier to perform the screw tightening operation.

[0031] The guide block 5 may be made of a synthetic resin.

[0032] 3A to 3C, the outer shape of the guide block 5 is, for example, the same as that of the radius fixing plate 2, so that it covers the entire radius fixing plate 2 and can be easily stacked. The back surface of the guide block 5 (the surface that contacts the radius fixing plate 2) is, for example, shaped to correspond to the front surface of the radius fixing plate 2 (i.e., the surface opposite to the surface that contacts the radius 3 and that contacts the guide block 5).

[0033] The guide block 5 for a radius fixation plate includes at least a distal portion 5x and a proximal portion 5y.

[0034] The distal portion 5x has a wide shape that can be placed on the distal region 2a of the radius fixation plate 2, and has a plurality of screw guide holes 5d for the fixing screws 4 that communicate with the screw insertion holes 2d of the radius fixation plate 2. The distal portion 5x is formed so as to completely cover, almost cover, or partially cover the distal region 2a of the radius fixation plate 2 when placed on the distal region 2a of the radius fixation plate 2.

[0035] The proximal portion 5y has an elongated shape that can be placed on the proximal region 2b of the radius fixation plate 2, and has a plurality of screw guide holes 5d for the fixing screws 4 that communicate with the screw insertion holes 2d of the radius fixation plate 2. The proximal portion 5y is formed so as to completely cover, almost cover, or partially cover the proximal region 2b of the radius fixation plate 2 when placed on the proximal region 2b of the radius fixation plate 2.

[0036] In this specification, the term "proximal portion" refers to the portion of the guide block 5 that is closer to the heart, similar to the radial fixation plate 2, and the term "distal portion" refers to the portion of the guide block 5 that is farther from the heart than the proximal portion.

[0037] As an example, the thickness of the guide block 5 is made thicker than the thickness of the radius fixation plate 2 to facilitate guiding the fixation screw 4. In such a case, as an example, the thickness of the radius fixation plate 2 is 2.4 mm, and the thickness of the guide block 5 is about three times that of the radius fixation plate 2, that is, 6 mm. However, as another example, the thickness of the guide block 5 may be the same or approximately the same as the thickness of the radius fixation plate 2. Even in such a case, the fixation screw 4 can be guided by the thickness of the guide block 5, compared to the case of using only the radius fixation plate 2.

[0038] In the distal portion 5a and the proximal portion 5b, a large number of circular screw guide holes 5d are formed, each extending in the thickness direction of the guide block 5 or in a direction inclined with respect to the thickness direction, in other words, in the thickness direction of the radius fixation plate 2 or in a direction inclined with respect to the thickness direction. Each screw guide hole 5d is formed and arranged corresponding to each screw insertion hole 2d. Therefore, in the distal portion 5a, or the proximal portion 5b, or both the distal portion 5a and the proximal portion 5b, a plurality of adjacent screw guide holes 5d can be formed and arranged in a direction that obliquely intersects with each other.

[0039] As shown in FIG. 2A to FIG. 2C and FIG. 4A, each screw guide hole 5d is composed of a large-diameter center tube guide portion 5e and a small-diameter rotating shaft portion through-hole 5f that is smaller than the inner diameter of the center tube guide portion 5e. A center tube regulating portion 5h composed of an annular edge portion is formed at the boundary portion between the center tube guide portion 5e and the rotating shaft portion through-hole 5f. The center tube regulating portion 5h is contacted with the tip of the center tube 13 of the tool 1 described later, and the center tube 13 is regulated in position so that it does not enter the rotating shaft portion through-hole 5f in each screw guide hole 5d beyond the center tube regulating portion 5h, thereby regulating the screw feed depth (i.e., the depth). As an example of the position of the center tube regulating portion 5h, it is located at a certain distance (for example, 5 to 6 mm) from the countersunk surface of the screw insertion hole 2d of the radius fixation plate 2 (i.e., the boundary between the head storage portion 2e and the female screw portion 2f).

[0040] The function of each screw guide hole 5d is to guide the axial direction when the male fixing screw 4 inserted into the screw insertion hole 2d is tightened and to regulate the depth of the fixing screw 4, and also to function as a base for other surgical tools.

[0041] In addition to the above function for the fixing screw 4, the guide block 5 itself can also function as a base for inserting various other instruments used during surgery.

[0042] When the radius fixation plate 2 is placed on the radius 3, the radius fixation plate 2 also bends along the radius 3. At this time, the proximal region 2b of the radius fixation plate 2 is bent relatively to the distal region 2a. The distal portion 5x and the proximal portion 5y are arranged to be relatively movable, i.e., relatively flexible, so that the guide block 5 also bends in response to such bending of the radius fixation plate 2. As an example of such an arrangement, the distal portion 5x and the proximal portion 5y are integrally configured while being connected by a connecting portion 20 such as some means or member.

[0043] As an example of the connecting portion 20, as shown in FIG. 3A to FIG. 3C, the distal portion 5x and the proximal portion 5y may be connected by a thin flexible portion 21 so as to be relatively movable. In this case, a groove 22 having at least half the thickness of the guide block 5 may be formed between the distal portion 5x and the proximal portion 5y from the front surface side (i.e., the surface opposite to the radius contact surface) of the guide block 5, from one end to the other in the width direction, and the thin flexible portion 21 may be formed on the back surface side as the remaining portion. The thickness of the thin flexible portion 21 may be, for example, 1 / 3 of the thickness of the guide block 5. This flexible portion 21 allows the distal portion 5x and the proximal portion 5y to be relatively flexible, and can follow the bending of the radius fixing plate 2. The width dimension of the thin flexible portion 21 is, for example, approximately the width dimension of the proximal portion 5y.

[0044] Also, as shown in Fig. 3B and Fig. 3C, the outer peripheral edge of the back surface of the guide block 5 (i.e., the surface on the side of the radius fixation plate) has at least three retaining claws 5c that can be engaged and held on the outer peripheral edge of the radius fixation plate 2. That is, one retaining claw 5c is arranged on the longitudinal edge of the proximal portion 5y, which is the right end of Fig. 3B, and two retaining claws 5c are arranged on the longitudinal edge of the distal portion 5x, which is the left end of Fig. 3B, on both edges in the width direction intersecting with the longitudinal direction. By arranging the retaining claws 5c in these three places, it is possible to hold the plate in a well-balanced and reliable manner.

[0045] 4A and 4B, each of the retaining claws 5c has a locking projection 5t that projects in a J-shape or an inverted J-shape in the thickness direction T of the guide block 5. The locking projection 5t projects so as to be securely locked to the boundary portion between the side surface 2q of the radius fixing plate 2 that is curved outwardly convexly in the lateral direction intersecting with the thickness direction T and the bottom surface 2r that contacts or faces the radius 3. However, the locking projection 5t does not come into contact with the bottom surface 2r that contacts the radius 3 so as not to hinder the radius fixing plate 2 and the radius 3 from being appropriately positioned.

[0046] More specifically, as shown in FIG. 4B, the locking projection 5t is formed to lock with the side surface 2q of the radius fixing plate 2 within a range between a first orthogonal line C1 that passes through the lower end position of the radius fixing plate 2 in the thickness direction T of the guide block 5 (i.e., the boundary portion between the side surface 2q and the bottom surface 2r) and is orthogonal to the thickness direction T of the guide block 5, and a second orthogonal line C2 that passes through the outermost edge of the radius fixing plate 2 and is orthogonal to the thickness direction T of the guide block 5. This is because if the locking projection 5t protrudes toward the radius 3 side from the first orthogonal line C1, the locking projection 5t will be pinched between the radius 3 and the radius fixing plate 2, and the radius 3 and the radius fixing plate 2 will not be appropriately fixed in position. Also, if the locking projection 5t is located on the opposite side of the radius 3 from the second orthogonal line C2, the locking action with respect to the radius fixing plate 2 will not be exerted, and there is a possibility that the holding and fixing will not be reliable.

[0047] Therefore, if the locking protrusion 5t is designed to lock onto the side surface 2q of the radius fixation plate 2 within the range between the first orthogonal line C1 and the second orthogonal line C2, when the radius fixation plate 2 is placed on the radius 3, even if the proximal region 2b of the radius fixation plate 2 bends relative to the distal region 2a, the proximal portion 5y of the guide block 5 can bend relative to the distal portion 5x while remaining engaged and held to the radius fixation plate 2 by the locking protrusion 5t of the retaining claw 5c, and as a result, the guide block 5 can follow the radius fixation plate 2.

[0048] Auxiliary holding claws 5r are arranged on the remaining edge of the guide block 5, except for the connecting portion 20 between the distal portion 5x and the proximal portion 5y. The reason for excluding the connecting portion 20 is to ensure flexibility at the connecting portion 20. It is preferable that the auxiliary holding claws 5r also have a locking protrusion 5t, similar to the holding claws 5c. As an example of the arrangement of the proximal portion 5y of the auxiliary holding claws 5r, in order to more securely hold the proximal portion 5y, the auxiliary holding claws 5r are arranged to face opposing edges along the longitudinal direction of the proximal portion 5y, as shown in FIG. 3B. As an example of the arrangement of the distal portion 5x of the auxiliary holding claws 5r, in order to more securely hold the distal portion 5x, a plurality of auxiliary holding claws 5r are arranged on edges along the width direction perpendicular to the longitudinal direction of the distal portion 5x (i.e., edges between a pair of holding claws 5c of the distal portion 5x) as shown in FIG. 3B.

[0049] If the arrangement of the retaining claws 5c on the edge of the guide block 5, or the arrangement of the retaining claws 5c and the auxiliary retaining claws 5r, is symmetrical about the longitudinal central axis of the guide block 5 when viewed from the back side as shown in Figure 3B, a balanced holding force can be exerted on the radius fixation plate 2.

[0050] In this way, when the means for holding the guide block 5 on the radius fixation plate 2 is to insert a screw from the guide block 5 side and screw it into the female thread of the radius fixation plate 2, if the screw tightening work for holding has to be redone or if the screw tightening work itself fails, the female thread of the resin radius fixation plate 2 will be damaged and the radius fixation plate 2 will have to be removed from the radius 3 and discarded, which is troublesome and involves problems such as a prolonged operation time. In contrast, if the holding claws 5c or the holding claws 5c and the auxiliary holding claws 5r are used, the holding force of the claws can be released and the operation can be redone any number of times, without damaging the resin radius fixation plate 2.

[0051] As shown in Figs. 3A to 3C, a removal groove 5q formed by, for example, a rectangular notch is formed at one end edge of the proximal portion 5y. The removal groove 5q is formed so that the boundary between the radius fixing plate 2 and the guide block 5 is exposed. Therefore, by inserting, for example, a raspatrium or a spatula into this removal groove 5q and inserting it into the boundary between the radius fixing plate 2 and the guide block 5, and twisting the radius fixing plate 2 and the guide block 5 to separate them, the holding force of each holding claw 5c and each auxiliary holding claw 5r near the removal groove 5q can be released. Then, by inserting a raspatrium or a spatula into the boundary between the radius fixing plate 2 and the guide block 5 in the remaining part, or by removing the guide block 5 from the radius fixing plate 2 by hand, the holding force of the other holding claws 5c and auxiliary holding claws 5r can be released and the guide block 5 can be removed from the radius fixing plate 2.

[0052] Furthermore, as shown in Fig. 3C and Fig. 5A to Fig. 5G, a metal wire 19 as an example of a linear marker is disposed around the entire outer edge of the distal part 5x and the proximal part 5y. This is for the following reason. When the fractured part is photographed with an X-ray, if the radius fixing plate 2 is made of resin, the radius fixing plate 2 itself is not reflected in the X-ray, and its position cannot be confirmed. For this reason, if an X-ray is taken while a guide block 5 (see Fig. 5A to Fig. 5B) having a metal wire 19 around the entire edge is placed and held on the resin radius fixing plate 2, the metal wire 19 around the entire edge of the guide block 5 is reflected, and the position of the radius fixing plate 2 can be confirmed based on the reflected metal wire 19 (see Fig. 5C to Fig. 5G).

[0053] FIG. 5A is a diagram showing a state in which the guide block 5 is placed and held on the resin radius fixing plate 2. FIG. 5B is an explanatory diagram showing the position of the metal wire 19 obtained by X-ray photography in the state of FIG. 5A and the position of the radius fixing plate 2 for comparison. FIG. 5C is a diagram showing a state in which the guide block 5 is placed and held on the resin radius fixing plate 2 on the radius 3. FIG. 5D is an explanatory diagram showing the position of the metal wire 19 obtained by X-ray photography on the radius 3 in the state of FIG. 5C and the position of the radius fixing plate 2 for comparison. FIGS. 5E to 5G are perspective views of the guide block 5 placed and held on the resin radius fixing plate 2 on the radius 3, as viewed from different angles.

[0054] Such wires 19 may be placed in the radial fixation plate 2 instead of the guide block 5, if desired.

[0055] The wire 19 is not limited to being disposed around the entire edge of the guide block 5, but may be disposed around a part of the edge of the guide block 5. For example, as shown in Figs. 6A to 6E, the wire may be disposed at least at one edge protruding along the width direction of the distal portion 5x and at two edges extending along the longitudinal direction of the proximal portion 5y and facing each other. In the case of the radius fixing plate 2 for the left hand shown in Figs. 6A to 6B, for example, at least one protruding edge of the distal portion 5x means a portion 19a (hereinafter referred to as the first marker 19a) of the edge protruding most to the right side in the width direction (i.e., the ulnar side). This means that in the case of the radius fixing plate 2 for the left hand, if the radius fixing plate 2 protrudes too much to the right side (ulnar side) of Fig. 6B or 6C, the radioulnar joint, which controls the rotation of the hand, will malfunction, and the hand will not be able to rotate. Therefore, in order to avoid such a situation, it is necessary that the distal portion 2a of the radius fixing plate 2 be able to confirm the position of the ulnar side by the first marker 19a.

[0056] At this time, as shown in Figures 6D to 6E, it is clinically recommended that the distal end 2a of the radius fixation plate 2 must be placed so as not to exceed the appropriate line D1 of the radius 3. In Figure 6D, due to the angle at which the radius fixation plate 2 is viewed, the first marker 19a appears to be closer to the proximal end than the most distal end, but when observed from a direction perpendicular to that part as shown in Figure 6E, it can be seen that the first marker 19a indicates the most distal line. For this confirmation, the first marker 19a is necessary.

[0057] Furthermore, in order to check the inclination of the longitudinal direction of the radius fixing plate 2 relative to the longitudinal direction of the radius 3, a pair of second markers 19b parallel to the longitudinal direction of the guide block 5 is also necessary.

[0058] In this way, by using the second marker 19b together with the first marker 19a on the distal ulnar side, if the photographer or operator understands the shape of the radius fixation plate 2 in advance, by aligning the positions of the first marker 19a and the second marker 19b, it becomes possible to grasp where the entire edge of the radius fixation plate 2 is located on the radius 3. Note that if the longitudinal edge of the proximal region 2bb is about the length of the radius fixation plate, there is almost no possibility of it interfering with the region where high-risk tissue is located, and it is considered that grasping the position is not essential, so the placement of the marker is omitted. However, if it is desired to confirm, a marker may be placed on the longitudinal edge of the proximal portion 5y on the opposite side to the distal portion 5x.

[0059] In the following, an example of a tool for rotating the fixing screw 4 will be described in order to explain the guiding and depth regulation of the fixing screw 4, but the tool is not limited to the following configuration.

[0060] 2A to 2C, the tool 1 for fixing a radial fixation plate screw includes at least a rotational force input portion 11, a rotating shaft portion 12, a center cylinder 13, and an outer cylinder 14, and may be made entirely of metal, or the center cylinder 13 and the outer cylinder 14 may be made of synthetic resin and the remaining portions may be made of metal.

[0061] The rotational force input unit 11 is a part that applies a rotational force around an axis to the tool 1, and is composed of a rod-shaped member. As an example, the rotational force input unit 11 may be connected to a surgical tool, and the rotational force from the surgical tool may be input to the rotational force input unit 11 to enable the tool 1 to rotate forward and backward around the axis. As another example, when rotating by hand, the tool 1 may have a flat surface portion 11a extending in the axial direction, and the flat surface portion 11a and the curved back surface portion of the flat surface portion 11a may be pinched with fingers to enable the tool 1 to rotate forward and backward around the axis. Since it is sufficient for the rotational force input unit 11 to rotate forward and backward around the axis to fasten and release the fastening screw 4, the flat surface portion 11a is not necessarily required.

[0062] The rotating shaft portion 12 is provided with a screw connection portion 12c at the tip of the shaft main body 12a, which is arranged coaxially with the rotational force input portion 11 and connected to be capable of rotating relative to the rotational force input portion 11, and a circular ring-shaped spring locking projection 12e near the base end of the shaft main body 12a that protrudes radially beyond the outer diameter of the shaft main body 12a.

[0063] The screw coupling portion 12c is disposed at the tip of the shaft main body 12a, and is a hexalobular screw rotation portion that can be coupled to the hexalobular hole 4j of the head 4c of the fixing screw 4 so as not to rotate relatively, and allows the fixing screw 4 to rotate forwards and backwards in order to fasten or release the fixing screw 4. The screw coupling portion 12c is configured as a hexalobular screw rotation portion in the shape of a hexalobular wrench that can engage with the hexalobular hole 4j of the head 4c when a hexalobular screw 4 is used as the fixing screw 4.

[0064] The center cylinder 13 is made of a cylindrical member.

[0065] The center cylinder 13 includes a center cylinder main body 13a and a first engagement projection 13c that projects radially from the outer circumferential surface of the base end of the center cylinder main body 13a.

[0066] The middle tube body 13a is arranged on the outer peripheral surface of the base end side of the hexagonal cross-sectional shaft body 12a of the rotating shaft portion 12, and has a hexagonal cross-sectional through hole as an example that is unable to rotate around the axis relative to the hexagonal cross-sectional shaft body 12a (in other words, rotatable integrally therewith) and can move axially between a rotation position A and an idling position B.

[0067] The threaded coupling portion 12c at the tip of the rotating shaft portion 12 always protrudes from the tip of the middle cylinder body 13a.

[0068] In the vicinity of the base end of the shaft body 12a, a coil spring 15 as an example of a biasing member 15 is arranged in a slightly compressed state between the annular base end surface 13d of the middle tube body 13a and the annular spring locking projection 12e, and the spring force of the coil spring 15 constantly biases the middle tube body 13a toward the tip side relative to the shaft body 12a, so that the middle tube body 13a is always located at the rotation position A, not the idling position B. However, the coil spring 15 is not necessarily required. For example, in the tool 1 with a simple configuration, the coil spring 15 can be omitted, and the middle tube 13 can be returned by hand to the initial position, the rotation position A, every time the fixing screw 4 is fastened, and the tool can be used while being careful not to move the middle tube 13 during the fastening operation of the fixing screw. Even in such a case, the idling operation described above can be performed at the idling position B.

[0069] As an example, the first engagement protrusion 13c is formed in a plate shape with one or more first engagement protrusions in the circumferential direction and a trapezoidal cross section curved in the radial direction. For example, the first engagement protrusions 13c are formed at predetermined intervals, for example, four first engagement protrusions 13c at intervals of 90 degrees. In the drawings, the first engagement protrusions 13c are simplified to be gear-shaped.

[0070] The outer cylinder 14 is configured as a cylindrical member having a diameter larger than that of the middle cylinder 13 and having a tapered shape.

[0071] The outer tube 14 is arranged outside the middle tube 13 so as to be relatively movable in the axial direction, and is equipped with an outer tube main body 14a having a circular through hole, and a second engagement protrusion 14c formed on the inner surface of the middle part of the outer tube main body 14a so as to protrude toward the radial center and which is engageable with the first engagement protrusion 13c.

[0072] The through hole of the outer cylinder 14 has a large inner diameter at the base end and the diameter becomes smaller in stages or gradually toward the tip, so that the middle cylinder 13 cannot come off the outer cylinder 14 in the axial direction toward the tip.

[0073] The outer cylinder 14 is disposed so that the tip end portion of the middle cylinder 13 is exposed from the tip of the outer cylinder 14 and covers the base end portion of the middle cylinder 13, the base end portion of the rotating shaft portion 12, and the tip portion of the rotational force input portion 11. Furthermore, a fixing pin (not shown) is inserted diametrically into the tip portion of the rotational force input portion 11 and the base end portion of the outer cylinder 14 to fix the tip portion of the rotational force input portion 11 to the base end portion of the outer cylinder 14. Thus, the rotational force input portion 11 and the outer cylinder 14 are configured to rotate forward and backward integrally.

[0074] The second engagement protrusion 14c of the outer cylinder 14 is formed, for example, in a plate shape with one or more circumferentially curved trapezoidal cross section in the radial direction. For example, the second engagement protrusion 14c is formed at a predetermined interval, for example, four at intervals of 90 degrees. In the drawings, the second engagement protrusion 14c is also shown simply as a gear shape.

[0075] Therefore, the first engagement protrusion 13c can move axially back and forth with respect to the second engagement protrusion 14c between a rotation position A where they are engaged with each other, and an idling position B where they are disengaged. That is, in the rotation position A, the first engagement protrusion 13c and the second engagement protrusion 14c are engaged around the axis and cannot rotate relatively around the axis. In the idling position B, the engagement between the first engagement protrusion 13c and the second engagement protrusion 14c around the axis is released and they can rotate relatively around the axis.

[0076] The coil spring 15 is positioned near the base end of the rotating shaft portion 12 with a gap between it and the rotating shaft portion 12 so as not to interfere with the forward and reverse rotation of the rotating shaft portion 12, and constantly biases the middle tube 13 toward the tip side along the axial direction so that the middle tube 13 is positioned at rotation position A.

[0077] The tool 1 having such a configuration can be used as follows.

[0078] First, the guide block 5 is placed on the radius fixation plate 2 and held by the holding claws 5c or the holding claws 5c and the auxiliary holding claws 5r. Then, as shown in Figures 2A and 5C, the guide block 5 and the radius fixation plate 2 are placed together on the radius 3 so that the radius fixation plate 2 straddles the fractured portion 3a of the radius 3.

[0079] 2A, a fixing screw 4 is inserted into one screw guide hole 5d of the guide block 5 and the screw insertion hole 2d of the radius fixation plate 2, and the screw coupling portion 12c of the rotating shaft portion 12 of the tool 1 is coupled into the hexalobular hole 4j of the head 4c of the fixing screw 4. In this state, the screw insertion hole 2d, the screw guide hole 5d, the fixing screw 4, and the tool 1 are held coaxially with each other.

[0080] Next, the rotational force input unit 11 of the tool 1 starts to rotate in the direction of fastening the fixing screw 4. As a result, the rotational force from the rotational force input unit 11 is transmitted to the outer tube 14, the middle tube 13 biased to the rotational position A by the coil spring 15, the rotational shaft unit 12, and the fixing screw 4, and the fixing screw 4 is screwed into the radius 3 while being guided by the screw guide hole 5d of the guide block 5. That is, since the middle tube 13 is located at the rotational position A, the rotational force from the outer tube 14 is reliably transmitted to the middle tube 13 by the engagement of the first engagement protrusion 13c and the second engagement protrusion 14c around the axis. At this time, the screw guide hole 5d of the guide block 5 guides the fixing screw 4 so that it advances smoothly in its axial direction, and the shaft unit 4a of the fixing screw 4 starts to be screwed into the radius 3. When the fixing screw 4 is screwed in, the main thread 4b of the shaft unit 4a of the fixing screw 4 performs a self-tapping action on the radius 3 and is screwed in.

[0081] 2B, as the fixing screw 4 continues to rotate in the tightening direction and is screwed into the radius 3, the center tube 13 advances in the center tube guide portion 5e of the screw guide hole 5d, and the center tube 13 comes into contact with the center tube regulating portion 5h. As the fixing screw 4 continues to rotate in the tightening direction even after the contact, the center tube 13 starts to retreat relative to the rotating shaft portion 12 as the fixing screw 4 continues to be screwed further into the radius 3 and advances in the axial direction. This means that the center tube 13 starts to move from the rotation position A toward the idling position B. At this time, as an example, the auxiliary thread 4d of the head 4c of the fixing screw 4 is screwed into the female thread portion 2f of the screw insertion hole 2d of the radius fixing plate 2, and the radius fixing plate 2 is appropriately held in position and fixed, such as by being in close contact with the radius 3.

[0082] As a result, as shown in FIG. 2C, the fixing screw 4 is located at a predetermined position (so to speak, a fixing screw fastening position) with respect to the radius fixation plate 2. Here, the predetermined position is, for example, a position where the head 4c of the fixing screw 4 contacts the countersunk surface of the screw insertion hole 2d of the radius fixation plate 2 (i.e., the boundary between the head storage section 2e and the female screw section 2f). At this time, the lower end of the head 4c of the fixing screw 4 is located at a position up to a certain distance (for example, 2 mm) from the countersunk surface of the screw insertion hole 2d. However, this is only one example, and the predetermined position may be a position shifted toward the opening side of the head storage section 2e from the countersunk surface, or conversely, may be a position that is inserted into the female screw section 2f side from the countersunk surface. When the fixing screw 4 is located at such a predetermined position, if the tool 1 moves the center cylinder 13 from the rotation position A to the idling position B, the engagement between the first engagement protrusion 13c and the second engagement protrusion 14c around the axis is released. Then, the outer cylinder 14 rotates idly relative to the middle cylinder 13, and it becomes impossible to transmit any more rotational force from the tool 1 to the fixing screw 4, and the screw tightening operation becomes impossible. As a result, the fixing screw 4 is maintained in a predetermined position relative to the radius fixation plate 2, and the depth and rotation of the fixing screw 4 are restricted. Note that the certain distance is determined by the thickness of the radius fixation plate 2 or the thickness of the head 4c of the fixing screw 4, and varies, so it is difficult to uniformly prescribe the certain distance, and so it is illustrated as an example.

[0083] When releasing the fastening, the fixing screw 4 can be loosened and removed by rotating the rotating shaft portion 12 in the reverse direction using the tool 1 or a general screwdriver without using the guide block.

[0084] According to the embodiment, the screw guide hole 5d can easily and reliably guide the fixing screw 4 when tightening not only in the distal region 2a of the radius fixation plate 2 but also in the proximal region 2b. In addition, even when the proximal region 2b of the radius fixation plate 2 is bent along the radius 3 and fixed relative to the distal region 2a, the proximal portion 5y of the guide block 5 can be relatively moved, for example, bent, relative to the distal portion 5x of the guide block 5. Therefore, the guide block 5 can be placed so as to be aligned with the radius fixation plate 2 in the bent state, and the screw guide hole 5d can more reliably guide the fixing screw 4 when tightening not only in the distal region 2a but also in the proximal region 2b. If the proximal region 2b cannot be bent along the radius 3 and fixed relative to the distal region 2a as described above, the guide block 5 may not be aligned with the radius fixation plate 2 and may partially float or come off the radius fixation plate 2.

[0085] According to the embodiment, the distal portion 5x and the proximal portion 5y are connected by the thin flexible portion 21, so that the distal portion 5x and the proximal portion 5y can be handled as one set, which is easy to handle during surgery, and prevents mistakes in assembling when selecting an appropriate guide block 5 from a plurality of guide blocks 5 of different sizes, etc. Furthermore, the thin flexible portion 21 can be formed in the guide block 5 simply by forming the groove 22, which makes manufacturing easy.

[0086] The present invention is not limited to the above-described embodiment, but can be embodied in various other forms.

[0087] 7A to 7C, the distal portion 5x and the proximal portion 5y may be configured as separate members, and the distal portion 5x and the proximal portion 5y may be disposed with a gap 25 therebetween. With this configuration, the distal portion 5x and the proximal portion 5y can be configured to be relatively movable.

[0088] As another modified example of the connecting portion 20, it is not limited to the thin flexible portion 21, but may be a hinge connecting portion 26 as shown in Fig. 8A to Fig. 8C. This hinge connecting portion 26 includes a first connecting member 26a having a pair of branched portions 26e whose tip is bifurcated, a second connecting member 26d interposed between the pair of branched portions 26e, and a pivot pin 26c connecting the branched portion 26e and the second connecting member 26d so as to be relatively rotatable. The first connecting member 26a is supported by the distal portion 5x, and the second connecting member 26d is supported by the proximal portion 5y, but conversely, the first connecting member 26a may be supported by the proximal portion 5y, and the second connecting member 26d may be supported by the distal portion 5x. The pivot pin 26c is disposed along a lateral direction perpendicular to the thickness direction of the guide block 5, and the second connecting member 26d is allowed to rotate relatively to the first connecting member 26a around the virtual rotation axis, so that the proximal portion 5y can bend relative to the distal portion 5x. In this example, the second connecting member 26d can rotate to any angle relative to the first connecting member 26a around the virtual rotation axis.

[0089] As yet another modified example of the connecting portion 20, instead of being limited to the thin flexible portion 21, as shown in Figures 9A to 9C, it may be a thin sheet 27 that is stretched between the distal portion 5x and the proximal portion 5y on the front surface side of the guide block 5. This thin sheet 27 allows the proximal portion 5y to bend relative to the distal portion 5x.

[0090] In addition, by appropriately combining any of the various embodiments or modifications described above, it is possible to achieve the effects of each of them. In addition, combinations of embodiments, combinations of examples, or combinations of embodiments and examples are possible, and combinations of features of different embodiments or examples are also possible. Although the present invention has been fully described in connection with the preferred embodiment with reference to the accompanying drawings, various changes and modifications will become apparent to those skilled in the art, and such changes and modifications are to be understood as being included within the scope of the present invention as defined by the appended claims, unless they depart therefrom. [Industrial Applicability]

[0091] The guide block for a radius fixation plate according to the above aspect of the present invention can easily and reliably guide the fixation screw of the resin radius fixation plate when it is screwed in. [Explanation of symbols]

[0092] 1 Radial Plate Fixation Screw Tool 2 Radial Fixation Plate 2a Distal region 2b Proximal region 2d screw insertion hole 2e Head storage section 2f Female thread 2q side 2r bottom 3 Radius 3a Fracture area 3b Radial body 3c fracture fragment 4 Fixing screws 4a Shaft 4b Lead screw 4c head 4d Sub-screw 4j hexalobular hole 5 Guide Block 5a Distal 5b Proximal part 5c retaining claw 5d screw guide hole 5e Middle cylinder guide part 5f Rotating shaft penetration part 5h Middle cylinder regulation part 5q Release groove 5r Auxiliary holding claw 5t locking protrusion 5x distal 5y Proximal 11 Rotational force input section 11a Flat part 12 Rotating shaft 12a Shaft body 12c Threaded joint 12e Spring locking protrusion 13 Middle tube 13a Middle cylinder body 13c 1st engagement protrusion 13d Proximal end surface 14 Outer cylinder 14a External cylinder body 14c 2nd engagement protrusion 19 Marker 19a First Marker 19b 2nd Marker 20 Connecting part 21 Thin-walled flexible section 22 Groove 25 Gap 26 Hinge joint 26a First connecting member 26c Pivot pin 26d Second connecting member 26e Branch A Rotation Position B Idle position C1 First orthogonal line C2 Second orthogonal line D1 Radius Appropriate Line

Claims

1. A guide block for a radial fixation plate, which is placed on the radial fixation plate to guide a fixation screw for fixing the radial fixation plate to a radius, a distal portion that can be mounted on a distal region of the radial fixation plate and has a screw guide hole for the fixation screw that communicates with a screw insertion hole of the radial fixation plate; a proximal portion that can be placed on a proximal region of the radial fixation plate and has a screw guide hole for the fixation screw that communicates with a screw insertion hole of the radial fixation plate; The distal portion and the proximal portion are arranged to be movable relative to each other, The distal end of the proximal portion is connected to the distal end of the proximal portion by a connecting portion that is disposed between the distal end of the proximal portion and connects the distal end of the proximal portion to the proximal end in a manner that allows the distal end of the proximal portion to be relatively flexible. Guide block for radial fixation plates.

2. a first retaining claw disposed at at least two positions on an edge of the distal portion and configured to retain the distal portion in position when placed on the distal region of the radial fixation plate; and a second retaining claw disposed at at least one end edge of the proximal portion for retaining the proximal portion in a position when placed on the proximal region of the radial fixation plate.

2. The guide block for a radial fixation plate according to claim 1.

3. and further comprising linear markers arranged at least at one location on a distal end edge of the distal portion and at least two locations on a pair of opposing end edges extending along a longitudinal direction of the proximal portion to indicate a position of the radial fixation plate guide block.

3. The guide block for a radius fixation plate according to claim 1.

4. The linear marker is a wire disposed around the entire outer edge of each of the distal portion and the proximal portion.

4. The guide block for a radial bone fixation plate according to claim 3.

5. The distal portion and the proximal portion are made of resin.

5. The guide block for a radius fixation plate according to claim 1.

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