JP4489053B2 - Pelvic correction plate - Google Patents

Description

  The present invention relates to a pelvic correction plate used in a three-point pelvic osteotomy performed to prevent hip subluxation due to hip dysplasia that occurs during the growth period of dogs.

  Hip dysplasia refers to a disease in which the pelvic part is shallow and the femoral head is in a chronic subluxation due to poor growth of the hip joint. Hip dysplasia is congenital, but there are many dogs that suffer from hip dysfunction. For this hip dysplasia, cut the pelvic bone (the hipbone) at three points (pubic bone, both sciatic bones and iliac bones), change the angle of the hip joint dent, and subluxate the femoral head Plastic surgery (three-point pelvic osteotomy) is performed to make it difficult to perform.

  A conventional pelvic correction plate is described in, for example, US Pat. No. 5,904,684.

  A conventional pelvic correction plate will be described with reference to the drawings. FIG. 7 is a perspective view showing a conventional pelvic correction plate for the left side. The right pelvic correction plate is configured as a mirror image of the left pelvic correction plate.

  The conventional pelvic correction plate (25) includes a iliac side (26) having a square flat iliac contact surface (28) and a sciatic side (27) having a square flat sciatic contact surface (29). As shown in the figure, the iliac contact surface (28) and the sciatic contact surface (29) are centered on a line connecting the approximate center of the iliac contact surface (28) and the approximate center of the sciatic contact surface (29). Inclined so as to rotate by a predetermined angle respectively, and are integrally connected. Therefore, the protruding side is thick, the opposite side is thin, and the side that does not contact the iliac and sciatica is composed of one plane.

  At the time of three-point pelvic osteotomy, after acetabular osteotomy, the positional relationship of the sciatic bone with respect to the iliac is determined, and the pelvis correction plate is applied so that the determined relative positional relationship is obtained. Fix to the iliac and sciatic bone with a fixed screw passed through (30, 31).

  As described above, the pelvis is corrected. However, since the acetabular rim protrudes on the side opposite to the sacrum, the conventional pelvic correction plate has a problem that the position where it can be applied is limited. Therefore, many pelvic correction plates having different sizes are prepared, and the optimum size is selected during the operation.

  The iliac surface that the pelvis plate contacts is a gentle concave curved surface, and the sciatic surface that the pelvic plate contacts is a gentle convex curved surface. On the other hand, the iliac contact surface and the sciatic contact surface of the conventional pelvic correction plate are flat so that the orientation of the sciatic bone can be freely adjusted until it is fixed with a fixing screw. Therefore, the iliac bone and the sciatic bone are fixed as described above in contact with several places.

  Therefore, in order to arrange the left and right sciatices at the same height and in a symmetrical direction, there is a problem that an operator is required to have a high level of skill.

  As described above, the conventional pelvic correction plate has a high degree of freedom, but it is difficult to easily perform stable pelvic correction.

  Furthermore, as described above, the contact area with the iliac bone and the sciatic bone is small, and because there is a gap in the non-contact portion, the healing period required to complete the pelvic correction after fixing is long was there.

US Pat. No. 5,904,684

  An object of the present invention is to provide safety and certainty associated with simplification of surgery in a pelvic correction plate used for three-point pelvic osteotomy to prevent subluxation of the hip joint due to hip dysplasia that occurs during the growth period of dogs. It is an object of the present invention to provide a pelvic correction plate that can improve the length and shorten the correction and healing period.

  One aspect of the pelvic correction plate for the left side or the right side of the present invention is a three-point pelvic osteotomy, which is used after acetabular osteotomy, and is fixed to the iliac side and fixed to the ischial bone. A pelvic correction plate comprising a sciatic side portion and a connecting portion connecting the iliac side portion and the sciatic side portion, and the iliac side portion and the sciatic side portion are long on the sacrum side and on the opposite side to the sacrum It is a short approximate triangle.

  Further, in the iliac side portion and the sciatic side portion, the substantially triangular shape of each surface in contact with the bone is expressed by α = 90 degrees, 20 degrees depending on the angles α, β, and γ of the vertices expressed by extending three sides, respectively. It is desirable that ≦ β ≦ 70 degrees and γ = 90 degrees−β.

  Furthermore, the flat triangle S1 represented by the three sides of the surface facing the iliac at the iliac side, and the flat triangle represented by the three sides of the surface facing the sciatic at the sciatic side. S2 is the relative position of the state obtained by keeping the side a1 of the triangle S1 and the side a2 of the triangle S2 in parallel and the angle θ formed by the triangles S1 and S2 being 10 degrees ≦ θ ≦ 60 degrees. In relation, it is desirable that the iliac side and the sciatic side are arranged.

  The different aspects of the pelvic correction plate for the left side or the right side of the present invention are used after the osteotomy of the acetabulum in three-point pelvic osteotomy, and the iliac side part that fixes the screw to the iliac bone, and the screw fixation to the sciatic bone. A pelvic correction plate comprising a sciatic side portion and a connecting portion connecting the iliac side portion and the sciatic side portion, and the iliac side portion and the sciatic side portion are long on the sacrum side and on the opposite side to the sacrum It has an edge that is short and recessed in a substantially arc shape. The recessed edge is dimensioned to be a predetermined distance from the acetabular edge.

  Further, the surface T1 facing the iliac bone at the iliac side and the surface T2 facing the sciatic at the sciatic side have an angle θ formed by the surfaces T1 and T2 of 10 degrees ≦ θ ≦ 60 degrees. It is desirable that the iliac side and the sciatic side are arranged in a relative positional relationship of the state obtained by this.

  Furthermore, the surface facing the iliac bone at the iliac side is a convex curved surface that matches the concave curved surface of the iliac bone, and the surface facing the sciatic bone at the sciatic side is the convex curved surface of the sciatic bone. A matching concave curved surface is desirable.

  Furthermore, it is desirable that each of the surface facing the iliac bone at the iliac side and the surface facing the sciatic bone at the sciatic side is subjected to uneven surface processing or groove processing.

  Furthermore, it is desirable that each of the surface facing the iliac bone at the iliac side and the surface facing the sciatic bone at the sciatic side is coated with hydroxyapatite.

  According to the present invention, as the range of adjustment and fixation to the hipbone is expanded, safe and reliable fixation is possible, the operation time can be shortened, the burden on the operator can be reduced, and the pelvis correction plate can be quickly and stably fixed to the hipbone. Can be performed. Thus, as a result of shortening the healing period, the physical and mental burden on the affected dog can be reduced and the burden on the owner can be reduced.

  In addition, the iliac side and sciatic side are long on the sacrum side, short on the opposite side of the sacrum, and have a substantially arc-shaped edge that is separated from the acetabular rim by a predetermined distance, so that the surrounding tissue, pelvis In addition, it is possible to obtain a remarkable effect that the space generated between the pelvic correction plates can be reduced to a minimum.

  The present invention will be described with reference to the drawings.

  FIG. 1 is a plan view showing a pelvis to which the pelvic correction plate of the present invention is applied. FIG. 2 is a side view showing a pelvis to which the pelvis correction plate of the present invention is applied. FIG. 3 is a perspective view showing an embodiment of the left pelvic correction plate of the present invention.

  The pelvic correction plate (1) of the present invention includes an iliac side (2) fixed to the iliac screw, a sciatic side (3) fixed to the sciatica, an iliac side (2) and a sciatic side. (3) and a connecting portion for connecting. The iliac side part (2) and the sciatic side part (3) have a substantially triangular shape with a long axial length on the sacrum side and a short axial length on the opposite side to the sacrum. The material of the pelvic correction plate and the fixing screw is selected from any of well-known techniques. For example, titanium or a titanium alloy can be exemplified.

  Further, the surface facing the iliac at the iliac side (2) is a convex curved surface (14) that matches the concave curved surface of the iliac, and the surface facing the sciatic at the sciatic side (3) A concave curved surface (15) that matches the convex curved surface of the sciatica. As specific shapes of the concave curved surface and the convex curved surface, a cross section perpendicular to the axial direction is a shape close to an arc. Since the radius of the arc changes depending on the type and age of the dog, it is preferable to prepare several types. However, the gap caused by a slight difference in curvature is small, so one type of shape should be applied in many cases. Is possible.

  At the time of three-point pelvic osteotomy, as in the past, after the osteotomy of the acetabulum, the convex curved surface (14) of the iliac side (2) is applied to the concave curved surface of the iliac, and the convex shape of the ischia The iliac bone and the sciatic bone can be fixed with the fixing screws passed through the screw fixing holes (16, 17) without considering the relative positional relationship by simply applying the concave curved surface (15) of the ischial side (3) to the curved surface. Can be fixed to.

  Further, by preparing several types having different relative positional relationships between the convex curved surface (14) and the concave curved surface (15), the degree of opening on the sciatic side can be adjusted. By adjusting the degree of opening on the sciatica side, the amount of sciatic bone applied to the acetabulum can be increased or decreased, and the pelvis can be easily corrected.

  In addition, since it has a substantially triangular shape, it can be widely separated from the acetabular rim (18), and can be fixed safely and reliably.

  FIG. 4 is a front view of the pelvic correction plate for the left side of the example.

  Furthermore, in the iliac side part (2) and the sciatic side part (3), the substantially triangular shape of each surface in contact with the bone is expressed by the apex angles (α, β, γ) expressed by extending the three sides respectively. = 90 degrees, 20 degrees ≦ β ≦ 70 degrees, and γ = 90 degrees−β.

  By making one to be a right angle, the sacrum side can be aligned, and by making the other two 20 to 70 degrees, sufficient strength can be obtained without hitting the acetabular margin.

  FIG. 5 is a side view of the pelvic correction plate for the left side of the example.

  A flat triangle (S1) represented by the three sides of the surface (14) facing the iliac at the iliac side (2), and a surface (15) facing the sciatic at the sciatic side (3) In the flat triangle (S2) represented by the three sides, the side (a1) of the triangle (S1) and the side (a2) of the triangle (S2) are kept parallel, and the triangles (S1) and (S2) The iliac side part (2) and the sciatic side part (3) are arranged in a relative positional relationship in a state obtained by setting the angle (θ) formed by the following to 10 degrees ≦ θ ≦ 60 degrees.

  The angle is determined from the above-mentioned range, and several types are prepared so that it becomes easy to select an optimum angle during the three-point pelvic osteotomy.

  In the embodiment of the present invention described above, there are three screw fixing holes (16) in the iliac side (2) and three screw fixing holes (17) in the sciatic side (3). The number may be three or more. Furthermore, the number and position of the screw fixing holes (16, 17) are not particularly limited.

  Further, the surface of the iliac side (2) facing the iliac (14) and the surface of the sciatic side (3) facing the sciatic (15) are subjected to uneven surface processing or groove processing. The processing method and specifications are selected from any of known techniques. By processing such as these, the contact area can be increased, and the pelvic correction plate can be stably and quickly fixed to the hipbone.

  Furthermore, each of the surface (14) facing the iliac bone at the iliac side portion (2) and the surface (15) facing the sciatic bone at the sciatic side portion (3) are each coated with hydroxyapatite. By performing such treatment, hydroxyapatite is absorbed and replaced by the hipbone, and the pelvic correction plate can be fixed to the hipbone at an early stage.

  Different embodiments of the pelvic correction plate of the present invention will be described with reference to the front view shown in FIG.

  The iliac side part (20) and the sciatic side part (21) of the pelvic correction plate (19) of this example are long in the sacrum side, short on the opposite side to the sacrum, and in a substantially arc shape with a predetermined distance from the acetabulum edge. It differs from the pelvic correction plate (1) of the previous embodiment in that it has a concave edge (24). Such a shape makes it possible to minimize the space created between the surrounding tissue, the pelvis and the pelvic correction plate.

It is a top view which shows the pelvis to which the pelvis correction plate of this invention is applied. It is a side view which shows the pelvis to which the pelvis correction plate of this invention is applied. It is a perspective view which shows one Example of the pelvic correction plate for the left side of this invention. It is a front view which shows the pelvis correction plate for left side shown in FIG. It is a side view which shows the pelvic correction plate for left side shown in FIG. It is a front view which shows the Example from which the pelvic correction plate for left side of this invention differs. It is a perspective view which shows the conventional pelvic correction plate for left side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,19 Pelvic correction plate for left side 2,6,20 Iliac side part 3,7,21 Sciatic side part 4 Fixing screw 5 Pelvic correction plate for right side 8 Left iliac 9 Right iliac 10 Left sciatic bone 11 Right sciatica 12 sacrum 13 left acetabulum 14 iliac contact surface 15 sciatic contact surface 16, 17, 22, 23 fixed screw hole 18 left acetabular rim 24 edge 25 pelvic correction plate 26 iliac side 27 sciatic side 28 intestine Bone contact surface 29 Sciatic contact surface 30, 31 Fixed screw hole S1, S2 surface a1, a2 side α, β, γ, θ Angle

Claims (5)

In three-point pelvic osteotomy for dogs, the iliac side used to fix the screw to the iliac bone, the sciatic side fixed to the sciatic screw, the iliac side and the sciatic side A pelvic correction plate composed of a connecting part that connects the parts, the iliac side part and the sciatic side part both have a long side extending in the direction of extension of the hipbone on the sacrum side , the sacrum side is long, Ri opposite side short substantially triangular der the sacrum,
An angle θ formed by both the surface facing the iliac at the iliac side and the surface facing the sciatic at the sciatic side is 10 ° ≦ θ ≦ 60 °, and the long sides on the sacrum side are Have a relative positional relationship of being spaced apart and maintaining parallelism,
The surface facing the iliac bone at the iliac side is a convex curved surface that matches the concave curved surface of the iliac bone, and the surface corresponding to the sciatic bone at the sciatic side is a concave shape that matches the convex curved surface of the sciatic bone Curved surface,
A pelvic correction plate for the left side or the right side. In the iliac side portion and the sciatic side portion, the substantially triangular shape of each of the surface facing the iliac bone at the iliac side portion and the surface facing the sciatic bone at the sciatic side portion extends three sides, respectively. The angle of the vertex corresponding to the portion in contact with the connecting portion on the sacrum side is α, the angle of the vertex corresponding to the portion on the opposite side of the sacrum is β, and the side separating from the connecting portion on the sacrum side 2. The left side or the right side according to claim 1 , wherein α = 90 degrees, 20 degrees ≦ β ≦ 70 degrees, and γ = 90 degrees−β, where γ is an angle of a vertex corresponding to the portion Pelvic correction plate. The left side or the right side according to claim 2, wherein the inclined edge extending from the portion on the sacrum side away from the connecting portion to the portion opposite to the sacrum is a substantially arcuate edge. Pelvic correction plate for use. Surface facing the iliac at the iliac side, and wherein each sciatic sides of the sciatic surface opposed to the claim 1, characterized in that they are subjected to uneven surface machining or grooving 3 The pelvic correction plate for left side or right side as described in any one. Surface facing the iliac at the iliac side, and wherein each sciatic sides of the sciatic and opposing surfaces, according to any of claims 1 to 4, characterized in that it is covered by hydroxyapatite Pelvic correction plate for left side or right side.

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