JP3041355B2 - Bone saw guide - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a osteotomy guide for guiding an osteotomy when cutting an ulna or the like.

[0002]

2. Description of the Related Art In recent years, ulnar carpal push-up syndrome (UC
As one of the treatments such as AS), ulnar shortening for shortening the length of the ulna is performed. In ulna shortening, the cut end is cut off by a desired amount after cutting the ulna, and the ulna is joined again at the cut portion to shorten the ulna. When joining the ulna at the cut portion, the fixation plate is applied along the ulna over the joint, and the fixation screw is screwed to the ulna through a plurality of holes formed in the fixation plate, so that the ulna Is fixed in the joined state.

In the ulna, a plurality of screw holes for screwing fixing screws are drilled in advance at positions corresponding to the holes of the fixing plate. However, since the ulna is later shortened by cutting, the amount of shortening is reduced. In consideration of the above, the interval between the screw holes is determined. Specifically, a template having a pair of adjacent drill guide holes with an interval dimension obtained by adding the shortening amount obtained by resection of the ulna is applied to the ulna, and a screw hole is formed in the ulna by guiding the drill guide holes. Set up.

[0004] Thereafter, a part of the space between the adjacent screw holes is cut away by an osteotomy saw with a space dimension obtained by adding the shortening amount, whereby the space dimension between the screw holes is reduced, and each hole of the fixing plate is reduced. And the respective screw holes match.

[0005] By the way, it is extremely difficult to perform a highly accurate cutting operation of the ulna using an osteotomy saw. In particular, it requires skill to operate the osteotomy accurately and freehand so that the cut surfaces of the bones are parallel, and if the appropriate resection is not performed, the joints of the ulna may be deformed. There were inconveniences that occurred.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a bone cutting saw guide which enables high precision bone resection by a bone cutting saw.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a fixing member fixed to a bone with screws.
An advancing and retreating member provided in the fixing member so as to be able to advance and retreat in parallel to the bone, and an axial line extending in the advancing and retreating direction of the advancing and retreating member, rotatably supported at the rear end of the fixing member, and A ball screw rotatably screwed to the rear end, a reciprocating member for checking the amount of reciprocation of the reciprocating member with respect to the fixed member due to rotation of the ball screw, and a scale engraved on the fixing member; The fixing member is a flat surface along the cutting direction of the bone to which the fixing member is fixed, and guides the bone cutting saw to a bone cutting position by the advanced retreating member tip, and retreats the retreating member tip. And an osteotomy guide surface for guiding the osteotomy along the osteotomy position according to (1).

More specifically, the fixing member is formed in a rectangular plate shape, and has a plurality of holes into which screws are inserted at predetermined intervals along a longitudinal direction; An advancing / retracting guide portion formed on both sides along the longitudinal direction of the fixed plate portion for guiding the advancing / retreating member in parallel to the bone; and a rotatably supporting tip of the ball screw rotatably behind the fixed plate portion. A first support portion standing at an end portion, wherein the reciprocating member is slidably held via the guide portions on both sides of the fixed member and is longer than a length dimension of the fixed plate portion and is parallel to each other. A pair of sliding portions extending rearward, a rear end of both sliding portions being integrally connected, a second supporting portion for screwing and supporting a ball screw opposed to the first supporting portion from a rear position, and both sliding portions. The end of the moving part is integrally connected, and the bone cutting saw guide surface is provided at a position forward of the fixing member. Characterized in that it is constituted by a bone saws guide.

In the case of performing osteotomy in, for example, ulna shortening by the osteotomy guide device of the present invention, the fixing member is fixed to the ulna with the distal end of the advance / retreat member facing a portion to be cut. At this time, the scale is checked, and the advance / retreat member is advanced to a size that provides a desired cutout amount by rotating the ball screw. The osteotomy guide surface is located at a bone cutting position, and cuts the ulna while guiding the osteotomy along the osteotomy guide surface. Thereby, the bone cutting saw can be accurately moved in the cutting direction, and cutting can be performed to make the cut surface flat.

Next, in one of the cut ulna, the scale is confirmed, and the advance / retreat member is retracted to a size to obtain a desired resection amount by rotating the ball screw. At this time, the advance / retreat member can be retracted to an extremely accurate position only by checking the scale and rotating the ball screw.

Then, the ulna is resected while guiding the bone cutting saw along the bone cutting saw guide surface. As described above, the cut surface is flattened by the accurate movement of the bone cutting saw, and a cut surface parallel to the cut surface of the other ulna previously cut can be formed with extremely high precision.

In the present invention, the scale is engraved on an upper surface of a sliding portion located between the osteotomy guide portion of the advance / retreat member and the second support portion and an upper surface of a fixing plate portion of the fixing member. It is preferable that the check is easy.

[0013] In the present invention, the bone cutting saw guide surface is formed to be inclined at a predetermined angle with respect to the bone to which the fixing portion is fixed.

The osteotomy method can be roughly classified into step cut osteotomy, lateral bone osteotomy, and oblique osteotomy. Among these methods, when the oblique osteotomy that can form a cut surface having a relatively large joint area is adopted, the osteotomy saw guide surface is formed so as to be inclined at a predetermined angle with respect to the bone. By doing so, the bone cutting saw can be accurately moved in the oblique direction with respect to the bone, and a highly accurate bone resection operation can be performed.

[0015]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view showing a bone cutting saw guide of this embodiment, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG.
FIGS. 4 (a) to 4 (d) are cross-sectional views taken along the line II-III. FIGS.
5A is a perspective view of a template, and FIG. 5B is a perspective view of a fixing plate.

As shown in FIG. 1, the bone cutting saw guide 1 of the present embodiment comprises a fixing member 2 fixed to a bone, and a reciprocating member 3 supported by the fixing member 2 so as to be able to advance and retreat. A ball screw 4 for moving the moving member 3 forward and backward is provided.

As shown in FIGS. 1 and 2, the fixing member 2 has a rectangular plate-like fixing plate portion 5 and a plate-like member that stands on the rear end of the fixing plate portion 5 and supports the ball screw 4. And the first support portion 6. A plurality of (two in this embodiment) bolt insertion holes 7 are formed in the fixing plate portion 5. The hole 7 is provided below (Fig. 4 shows) to pre-drilled screw-holes y ₁ and a position corresponding to y ₂ in ulnar A as. As shown in FIG. 3, a pair of forward / backward guide portions 8 are formed on both sides of the fixed plate portion 5 to guide the forward / backward member 3 so as to be able to move forward and backward.

As shown in FIGS. 1 and 3, the advance / retreat member 3 is slidable on both advance / retreat guide portions 8 of the fixed plate portion 5 so as to sandwich the fixed plate portion 5 from outside on both sides thereof. Is provided with a pair of sliding portions 9 abutting on the sliding member 9. Both sliding parts 9 are shown in FIG.
As shown in FIG. 2, the fixed plate portions 5 extend longer than the length of the fixed plate portion 5 in parallel with each other, and are integrally connected by a plate-shaped second support portion 10 standing at the rear end. The second support 10
The ball screw 4 is provided so as to face the first support portion 6 of the fixing member 2 in parallel, and the tip of the ball screw 4 is rotatably supported by the first support portion 6 via a retaining member 11. It is screwed and supported by the second support portion 10.

At the rear end of the ball screw 4, a knob 12 is provided. By operating the knob 12 to rotate the ball screw 4, the first support 6 and the second support 10 are rotated.
The distance between the moving member 3 and the moving member 3 moves forward and backward with respect to the fixed member 2.

As shown in FIGS. 1 and 2, the advancing / retreating member 3 is provided integrally with the leading ends of the two sliding portions 9 in front of the fixed plate portion 5 by connecting the two sliding portions 9 to each other. A block-shaped bone cutting saw guide 13 is provided. As shown in FIG. 2, the bone cutting saw guide portion 13 has a bone cutting saw guide surface 14 formed on the entire end surface. Bone saw guide surface 14
Is a flat surface along the cutting direction of the ulna A to which the fixing member 2 is fixed, and is provided at a predetermined angle with respect to the ulna A. Osteotomy guide surface 1 inclined in this way
4 is oblique to the ulna A as described later in FIG.
The guided bone cutting saw 31 is guided. In the present embodiment, by providing the osteotomy saw guide surface 14 in an inclined manner, as shown in FIG. The osteotomy saw 31 can be moved accurately and obliquely with respect to the ulna A in order to make it suitable for the case of adopting.
However, when the transverse osteotomy is used in another osteotomy, for example, the osteotomy guide surface 14 (not shown) may be provided so as to be perpendicular to the ulna A.

As shown in FIG. 1, a scale 15 and a reference line 16 for checking the amount of advance and retreat of the advance / retreat member 3 with respect to the fixation member 2 due to the rotation of the ball screw 4 are provided on the advance / retreat member 3 and the fixed member 2. Is engraved. The scale 15
Are engraved on the upper surface of the sliding portion 9 at predetermined intervals (every 1 mm in the present embodiment), and the amount of advance and retreat is set by a scale 15 that matches a reference line 16 engraved on the upper surface of the fixed plate portion 5. Can be checked.

Next, an example of use of the osteotomy guide 1 of the present embodiment in ulnar shortening will be described. First, a desired area including the resection x of the ulna A is exposed below the periosteum.

Next, as shown in FIG.
Using a forceps (not shown), the template 17 is cut out of the ulna A
It is fixed to a predetermined range including x. Used in ulnar shortening
As shown in FIG. 5 (a), the template 17
Formed into a plate that curves so as to adhere along the surface of bone A
5 drill holes 18 and 1
9, 20, 21, and 22 are formed. In FIG. 4 (a)
As shown, each of the drill holes 18, 1
Ulna by drill 23 through 9,20,21,22
4A shows a screw hole for a fixing bolt 24 shown in FIG.
y₁, Y_Two, Y _Three, Y_Four, Y_FiveDrilling. At this time
Screw hole y formed in bone A₁, Y_Two, Y _Three, Y_Four, Y_Five
Is the ulna A divided after resection of the resection x of the ulna A
FIG. 5 which maintains the joined state in order to join again
(B) fixing bolt for fixing the fixing plate 25 shown in FIG.
24 is screwed. That is, the template shown in FIG.
Drill holes 18,19,20,21,22
The distance between the first drill hole 18 and the second drill hole 19
Is the first hole 26 of the fixing plate 25 shown in FIG.
And the distance between the second hole 27 and the template
17 between the third drill hole 20 and the fourth drill hole 21
Distance between the fourth drill hole 21 and the fifth drill hole 22
Are the third hole 28 and the fourth hole 2 of the fixing plate 25, respectively.
9 and the distance between the fourth hole 29 and the fifth hole 30.
I am responding. And the second drill of template 17
The distance u between the hole 19 and the third drill hole 20 is equal to the cut length of the ulna A.
The second portion of the fixing plate 25 is located corresponding to the
The dimension obtained by adding the resection amount to the interval v between the hole 27 and the third hole 28
Has become the law. The resection amount of ulna A is predetermined before the operation.
Therefore, the second domain corresponding to this amount of resection is
It has an interval dimension u between the drill hole 19 and the third drill hole 20
Template 17 is used. With this,
Fixation plate after ulna A is resected by the resected amount
25 holes 26, 27, 28, 29, 30
Screw hole y formed in ulna A by plate 17₁,
y_Two, Y_Three, Y_Four, Y_FiveCorresponding to In this embodiment
The amount of ulna A removed is α mm. Therefore, the template
The port 17 has a second drill hole 19 and a third drill hole 20.
Between the second hole 27 of the fixing plate 25 and the third
The one with the dimension u which is obtained by adding αmm to the distance from the hole 28 is used.
It is.

Subsequently, as shown in FIG. 4B, the osteotomy guide 1 of the present embodiment is fixed to the ulna A from which the template 17 has been removed. At this time, the pair of holes 7 formed in the fixing plate portion 5 are inserted into the first drill holes 1 of the template 17.
The fixing plate portion 5 is connected to the ulna A by screwing the fixing bolts 24 so as to correspond to the screw holes y ₁ and y ₂ formed in the ulna A by the holes 8 and the second drill holes 19 and cut the bone. The saw guide 1 is fixed.

Next, the ball screw 4 is rotated,
The advance / retreat member 3 is advanced. Since the cut amount of the ulna A in this embodiment is α mm, the advance / retreat member 3 is advanced while checking the scale 15 (see FIG. 1) until the lower edge of the bone cutting saw guide surface 14 advances by α mm. At this time, the osteotomy guide surface 14 is in contact with the second drill hole 1 of the template 17.
9 and the third drilled hole 20, the screw hole y formed
₁ and y ₂ . And the bone cutting saw guide surface 14
The ulnar A is cut by moving the osteotomy saw 31 along.
Here, as described above, after fixing the osteotomy saw guide device 1 of the present embodiment to the ulna A, the work of making the advance / retreat member 3 advance until the lower edge of the osteotomy guide surface 14 advances by α mm. However, since the resection amount αmm of the ulna A is already determined, the advance / retreat member 3 is advanced in advance until the osteotomy saw guide surface 14 advances by αmm, and then the osteotomy guide of the present embodiment is introduced to the ulna A. The tool 1 may be fixed.

Thereafter, as shown in FIG. 4C, the ball screw 4 is rotated to move the advance / retreat member 3 backward,
While checking the scale 15 (see FIG. 1), the lower edge of the bone cutting saw guide surface 14 is retracted by α mm. As a result, a part of the ulna A to be cut off in front of the osteotomy saw guide surface 14 is exposed by α mm, and the osteotomy saw 3 is cut along the osteotomy guide surface 14.
The ulna A can be accurately resected by only α mm by simply moving the ulna A.

Then, as shown in FIG.
Of the osteotomy saw 1 from the osteotomy
Are fixed to the ulna A with the fixing bolts 24 to maintain the joint state of the ulna A.

[Brief description of the drawings]

FIG. 1 is a plan view showing an osteotomy guide according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is an explanatory view showing a method of using the osteotomy guide in ulnar shortening.

5A is a perspective view of a template, and FIG. 5B is a perspective view of a fixing plate.

[Explanation of symbols]

A: ulna (bone), 1: bone cutting saw guide, 2: fixing member,
DESCRIPTION OF SYMBOLS 3 ... advance / retreat member, 4 ... ball screw, 5 ... fixed plate part, 6 ... 1st support part, 7 ... hole, 8 ... advance / retreat guide part, 9 ... sliding part, 10
... Second support portion, 13: Bone saw guide portion, 14: Bone saw guide surface, 15: Scale.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) A61B 17/14 A61B 17/56-17/92

Claims (4)

(57) [Claims] 1. A fixing member fixed to a bone by screws, an advancing / retreating member provided on the fixing member so as to be able to advance and retreat in parallel to the bone, and an axis extending in the advancing / retreating direction of the advancing / retreating member. A ball screw rotatably supported by the rear end of the member and rotatably screwed to the rear end of the advance / retreat member, and an amount of advance / retreat of the advance / retreat member with respect to the fixed member due to rotation of the ball screw is confirmed. Scales engraved on the reciprocating member and the fixing member, and a flat surface formed at the distal end of the reciprocating member and along the cutting direction of the bone to which the fixing member is fixed, and the bone formed by the advanced reciprocating member tip A bone cutting saw guide surface which guides the bone cutting saw to a cutting position and guides the bone cutting saw along a bone resection position by the retracted distal end of the advance / retreat member. 2. The fixing member is formed in a rectangular plate shape,
A fixed plate portion formed with a plurality of holes for inserting screws at predetermined intervals along the longitudinal direction, and formed on both sides along the longitudinal direction of the fixed plate portion, so that the reciprocating member can be moved to the bone. An advancing / retracting guide portion that guides the ball screw in parallel, and a first support portion that stands rotatably at the rear end of the fixed plate portion by rotatably supporting the tip of the ball screw. A pair of sliding portions, which are slidably held via the guide portions on both sides of the member and extend in parallel with each other and longer than the length of the fixed plate portion, and rear ends of both the sliding portions are integrally connected. Then, the second support portion, which is opposed to the first support portion from the rear position and screwably supports the ball screw, and the leading ends of both sliding portions are integrally connected,
The bone cutting saw guide according to claim 1, further comprising: a bone cutting saw guide portion provided with the bone cutting saw guide surface at a position forward of the fixing member. 3. The scale is engraved on an upper surface of a sliding portion located between the bone cutting saw guide portion of the reciprocating member and the second support portion and an upper surface of a fixing plate portion of the fixing member. The bone cutting saw guide according to claim 2, characterized in that: 4. The bone cutting saw guide surface according to claim 1, wherein said bone cutting saw guide surface is formed to be inclined at a predetermined angle with respect to the bone to which said fixing member is fixed. Bone saw guide.