JP2002360592A - Drill and reamer for bone perforation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drill structured for preventing fixing of the drill and a guide member caused by the compression of bone powder, etc., generated in bone perforation in a gap between the guide member and the drill, concerning the drill for bone perforation having an axis hole which a guide member inserted to a bone is put through slidably. SOLUTION: A horizontal hole 13 formed putting through from the inner surface 11b of the axis hole to the outside surface 1b of the drill and having a diameter ranging 0.5 to 2 time of the diameter of an axis hole 11 is formed so that at least a part of this hole 13 may exist at a position within three times of the diameter of the hole 11 from a drill tip 1a. Thus, the bone powder, etc., B having entered in a gap 12 from the tip 1a is discharged from the hole 13 to prevent the compression of the bone powder B within the gap 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bone drill and a bone reamer used for drilling a hole for an implant in a surgical operation such as orthopedic surgery, oral surgery, and dentistry.

[0002]

2. Description of the Related Art In general, implants such as fracture treatment members, artificial bones, artificial joints, and artificial roots, which are used in the medical fields such as orthopedic surgery, oral surgery, and dentistry, are commonly used to replace internal bones (living bones) by surgical operations. It is attached.

For example, a screw which is a screw member for crimping and fixing a bone at a fracture site is used as a member for treating a fracture, and a screw member for attaching an implant such as an artificial bone, an artificial joint or an artificial tooth root to a living bone. However, it is very difficult to screw the screw into a predetermined position during the operation.

[0004] Therefore, in order to screw the screw into a predetermined position, generally, a prepared hole is made in the bone using a drill or a reamer, and then a thread is formed in the prepared hole with a tap, and finally, The procedure of screwing in the screw is adopted, but if the screw length is long or if you want to make the screwing position accurate, before drilling the pilot hole, guide pins and guide wires (hereinafter referred to as “guide members”) Is inserted into the bone, and the screwing position of the screw is determined in advance.

Since the guide member is smaller in diameter than the screw, it can be easily inserted into the bone, the insertion position can be easily corrected, and the insertion can be performed while observing by X-ray photography. Position can be determined accurately.

[0006] A drill having a shaft hole through which the guide member can be inserted along the rotation axis of the drill from the rear end side of the guide member inserted into the bone and not buried in the bone,
The shaft hole is aligned with the guide member and inserted, and the guide member is used as a guide to slide the drill to drill a bone (see FIG. 3). After drilling with a drill, the drilled holes are sequentially processed using a reamer or tap having a shaft hole through which a guide member similar to the drill can be inserted to form a female screw, and after removing the guide member, screw in the screw. Thereby, the screw is accurately mounted at a predetermined position.

However, when drilling is performed using the above-mentioned guide member, as shown in FIG. 3, bone fragments and bone powder (hereinafter referred to as “bone powder etc.”) B, which are cutting chips of the bone A, are drilled at the tip of the drill. There is a case where the guide member 2 and the drill 1 enter the gap 12 between the guide member 2 and the shaft hole 11 of the drill 1 one after another, are compacted by the rotation of the drill, and eventually close the gap 12, thereby fixing the guide member 2 and the drill 1. is there. When the guide member 2 is fixed to the drill 1, the rotation of the drill 1 causes the guide member 2 to rotate together with the drill 1.
May be further inserted from a predetermined position or may be pulled out together with the drill 1 when the drill 1 is pulled out, so that the function as a guide at the time of thread cutting by a reamer or a tap is lost. Further, when the guide member 2 is further inserted from a predetermined position, there is a possibility that the guide member 2 may penetrate the bone A and insert into a dangerous part in the body.

[0008] When the hole is finished by a reamer after drilling, the same problem as described above may occur.

In order to avoid such a problem of sticking, it is conceivable to increase the shaft hole diameter of the drill (or reamer) to increase the gap between the drill and the guide member. It cannot be adopted because there is a problem that the displacement of the rotating shaft increases and the drilling accuracy decreases.

[0010]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a structure for preventing the guide member and the drill (or reamer) from sticking to each other by bone dust or the like when cutting the bone using the guide member. To provide a drill (or reamer).

[0011]

According to a first aspect of the present invention, a shaft hole is formed along a rotation axis of a drill, and a guide member inserted into a bone is slidably inserted into the shaft hole. It is a drill for bone drilling comprised as mentioned above, Comprising: A horizontal hole penetrating from the inner surface of this shaft hole to the outer surface of the drill is formed.

According to a second aspect of the present invention, at least a part of the opening of the lateral hole on the inner surface side of the shaft hole is located at a position within three times the diameter of the shaft hole from the tip of the drill toward the rear end of the drill. The bone drill according to claim 1, wherein:

According to a third aspect of the present invention, the diameter of the opening of the side hole on the inner surface side of the shaft hole is 0.5 to 2 times the diameter of the shaft hole. It is a drill for bone perforation described.

According to a fourth aspect of the present invention, a bone hole is formed along the rotation axis of the reamer, and a guide member inserted into the bone is slidably inserted into the shaft hole. A bone piercing reamer, characterized in that a lateral hole penetrating from the inner surface of the shaft hole to the outer surface of the reamer is formed.

According to a fifth aspect of the present invention, at least a part of the opening of the side hole on the inner surface side of the shaft hole is present at a position within three times the diameter of the shaft hole from the tip of the reamer toward the rear end of the reamer. The bone piercing reamer according to claim 4, characterized in that:

According to a sixth aspect of the present invention, the diameter of the opening of the lateral hole on the inner surface side of the shaft hole is in the range of 0.5 to 2 times the diameter of the shaft hole. 6. The reamer for bone perforation according to 5. [Operation] According to the invention of claim 1, bone powder or the like that has entered the gap between the guide member and the shaft hole of the drill from the tip of the drill,
It is pushed toward the rear end of the drill, and eventually reaches the position of the lateral hole, and is sequentially discharged to the outer surface of the drill through the lateral hole, so that bone powder and the like do not stay and consolidate in the gap. Thus, the guide member and the drill are prevented from sticking to each other.

According to the second aspect of the present invention, since the distance from the tip of the drill to the side hole is not excessive, bone powder or the like that has entered from the tip of the drill easily reaches the side hole before being compacted too much in the gap. Since it is discharged, the prevention of sticking can be performed more reliably.

According to the third aspect of the present invention, by setting the diameter of the side hole to the predetermined range, it is possible to easily discharge bone meal and the like within a range that does not excessively reduce the strength of the drill itself.

It is apparent that the above-mentioned functions and effects can be similarly obtained by replacing the drill with a reamer.
The same functions and effects as those of the inventions of the first to third aspects are obtained.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a bone drill according to the present invention will be described in detail with reference to the drawings. (Note that, as described above, since the bone drilling reamer has the same operation and effect as the bone drilling drill,
In the description of the embodiment, a bone drill is used as a representative. )
FIG. 1 is a schematic view illustrating the behavior of bone meal and the like when a bone drill having a side hole according to one embodiment of the present invention is used in combination with a guide pin as a guide member. FIG. It is an image figure which shows the distribution of the powder pressure of the drill longitudinal direction inside the clearance gap between a shaft hole and a guide pin, (a) has used the conventional drill which does not have a horizontal hole, (b) has the horizontal hole of this invention. This is the case where a drill is used.

As shown in FIG. 1, the drill according to the present embodiment has a predetermined diameter penetrating from the inner surface 11b of the shaft hole 11 to the outer surface 1b of the drill 1 at a position separated from the drill tip 1a by a predetermined distance. Two cylindrical lateral holes 13 are formed at target positions with respect to the drill rotation axis at right angles to the drill rotation axis. Bone meal etc. generated by cutting with drill 1 B
Enters the gap 12 from the drill tip 1a, but is sequentially discharged from the lateral hole 13, so that the powder pressure in the gap 12 is slightly closer to the rear end from the drill tip 1a as shown in FIG. However, since the pressure is released at the opening of the lateral hole 13, the pressure does not rise above a certain value and does not lead to fixation. On the other hand, when a conventional drill having no lateral hole 13 is used, since there is no escape route for the bone powder B or the like, the powder is compacted with time and the powder pressure increases, and finally, as shown in FIG. The maximum pressure exceeds the pressure at which sticking occurs.

If the position of the lateral hole 13 is too far away from the tip 1a of the drill, it becomes difficult to discharge the bone powder B and the like, so that at least a part of the lateral hole 13 exists at a position within about three times the diameter of the shaft hole 11. It is preferable to form it. Shaft hole 1
The reason why the diameter is set to be within about three times the diameter of one is that the position where a fixed substance is generated in the gap 12 when drilling with a conventional drill having no lateral hole is the position from the drill tip 1a to about three times the diameter of the shaft hole 11. This is because it is often the case (see examples described later) that it is desirable to discharge the bone powder B or the like to this position.
The position of the side hole 13 is preferably from the viewpoint of prevention of sticking because the bone powder B is discharged immediately as the position is closer to the drill tip 1a. However, if the position is too close to the tip 1a, the cutting edge of the drill tip is easily damaged. It is preferable to form them at an appropriate distance from the substrate.

The diameter of the lateral hole 13 is preferably larger as the bone powder B is easily discharged, but if it is too large, the strength of the drill 1 is excessively reduced.
It is recommended to select from a range of about twice.

The shape of the lateral hole 13 is not particularly limited, and may be an elliptical column or a polygonal column in addition to the columnar shape of the present embodiment.
It is also preferable to use a tapered shape in which the cross section increases toward b, since bone powder and the like are unlikely to be clogged in the lateral hole. Also, the side hole 13
There is no particular limitation on the direction of the drill hole, and the drill hole is formed in a direction perpendicular to the drill rotation axis of the present embodiment.
Can be formed diagonally in the direction away from the drill tip 1a toward the outer side surface 1b of the drill from the gap 12 to the side hole 1
3 is preferable because the flow of bone meal and the like to 3 becomes smooth.

The number of the lateral holes 13 is not particularly limited either, and may be one or three or more in addition to the two in this embodiment, and may be appropriately selected in combination with the diameter and shape of the lateral holes 13. is there. In the case of the present embodiment, the drill tip 1a
In this example, two pieces are arranged so as to face each other at the same length in the circumferential direction. However, a plurality of pieces may be provided at different lengths from the drill tip 1a, and a plurality of pieces may be provided. A plurality may be provided in the circumferential direction.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to confirm the effect of the present invention, a lateral hole is formed in the outer surface near the tip of a blade portion of a conventional drill and reamer used for drilling bone in combination with a guide pin as a guide member. The present invention was used as an example, and a conventional product having no side hole was used as a comparative example, and a test was conducted in which the femur of a pig was drilled using each drill or reamer and whether or not the shaft hole of the drill or reamer was fixed to the guide pin. Was carried out.

Table 1 shows the specifications and test results of drills and reamers which are drilling tools used in the test. The drill and reamer had the same outer diameter of 8 mm, the diameter of the shaft hole was 3.6 mm, and the diameter of the guide pin was 3.2 mm. The horizontal hole was formed in a columnar shape perpendicular to the rotation axis of the drill or reamer, and the center of the horizontal hole was formed at a position 8 mm from the tip of the blade of the drill or reamer.

As shown in Table 1, No. 1 was not provided with a horizontal hole.
When the drill No. 1 was used, sticking between the drill and the guide focus occurred in one of the four repetitive tests, and No. 1 in which no lateral hole was provided. When the reamer No. 4 was used, sticking between the reamer and the guide pin occurred in two of the four repetitive tests. The fixed substance such as bone powder formed in the gap between the drill or reamer and the guide pin after the fixing occurs is relatively soft near the tip of the drill or reamer, but becomes harder toward the rear end, and its length is about 5 to 10 mm. Met.

On the other hand, No. 2 and No.
No. 3 drill, No. 3 When the reamer No. 4 was used, none of the reamers was fixed to the guide pin. As a result of observing the gap between the drill or reamer and the guide pin after the test, a lump of slightly hard bone powder or the like was observed from the drill or reamer tip to the side hole, but bone powder or the like was found from the side hole to the rear end side. Was scarcely present, and even if present, it was very soft.

[0030]

[Table 1]

From the above test results, in the case of the conventional product (comparative example) having no horizontal hole, the sticking to the guide pin as the guide member may occur. It has been confirmed that the use of the reamer can prevent sticking to the guide pin as the guide member.

[0032]

As described above, according to the present invention, fixation of the drill (or reamer) to the guide member can be reliably prevented with a simple structure, and more accurate and accurate bone drilling can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating the behavior of bone meal and the like when the drill for drilling bone according to the present invention is used in combination with a guide member (guide pin).

FIG. 2 is an image diagram showing a powder pressure distribution in a longitudinal direction of a drill inside a gap between a drill shaft hole and a guide member (guide pin).

FIG. 3 is a schematic diagram illustrating the behavior of bone meal and the like when a conventional bone drill is used in combination with a guide member (guide pin).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Drill, 1a ... Tip, 1b ... Outer surface 2 ... Guide member (guide pin) 11 ... Shaft hole, 11b ... Inner surface 12 ... Gap 13 ... Side hole A ... Bone B ... Bone meal etc.

Claims (6)

[Claims] 1. A bone drilling drill wherein a shaft hole is formed along a rotation axis of the drill, and a guide member inserted into a bone is slidably inserted through the shaft hole. hand,
A drill for bone drilling, wherein a lateral hole penetrating from the inner surface of the shaft hole to the outer surface of the drill is formed. 2. A method according to claim 1, wherein at least a part of the opening of the lateral hole on the inner surface side of the shaft hole is present at a position within three times the diameter of the shaft hole from a drill tip to a drill rear end. The drill for bone drilling according to claim 1. 3. The bone according to claim 1, wherein the diameter of the opening of the side hole on the inner surface side of the shaft hole is in a range of 0.5 to 2 times the diameter of the shaft hole. Drill for drilling. 4. A bone piercing reamer, wherein a shaft hole is formed along a rotation axis of the reamer, and a guide member inserted into a bone is slidably inserted into the shaft hole. hand,
A reamer for bone drilling, wherein a lateral hole penetrating from the inner surface of the shaft hole to the outer surface of the reamer is formed. 5. The apparatus according to claim 5, wherein at least a part of the opening of the side hole on the inner surface side of the shaft hole is present at a position within three times the diameter of the shaft hole from the tip of the reamer toward the rear end of the reamer. The reamer for bone drilling according to claim 4. 6. The bone according to claim 4, wherein the diameter of the opening of the side hole on the inner surface side of the shaft hole is in a range of 0.5 to 2 times the diameter of the shaft hole. Reamer for drilling.