JP2001212151A - Punch stopper for bone operation and punch for bone operation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a punch stopper for a bone operation capable of simply constituting an internal structure and easily operating to engage an engaging part with an engaging groove of a shank of a punching member. SOLUTION: The stopper 10 is used in a state in which a shank 22 of a reamer 20 is inserted into an axial hole 11p of a first member 11 and an axial hole 12p of a second member 12. Then, if the member 11 is sufficiently deeply engaged with the member 12 and a tapered surface 12d of the member 12 pushes an engaging sphere 13 to an opening 11d, the sphere 13 is partly protruded through the opening 11d in the hole 11p. As a result, a groove 22d formed at the shank 22 is engaged with the sphere 13. The stopper 10 is axially held of the shank 22 is such a state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling stopper for bone surgery and a drilling tool for bone surgery, and more particularly, to an apparatus for controlling a drilling depth when drilling a bone with a drilling member.

[0002]

2. Description of the Related Art Generally, in various types of bone surgery, in order to introduce various kinds of implants such as bone screws into bone, an introduction hole for introducing the implant may be formed in advance. Examples of a drilling member for drilling a bone include a guide wire, a drill, and a reamer. In some cases, a perforation stopper for bone surgery for restricting (restricting) the depth of an introduction hole formed in a bone is attached to these perforation members. As this kind of drilling stopper for bone surgery, a stopper configured to be fixed to an outer peripheral surface of a shaft body portion of a drilling member using a set screw or the like is provided, and a stopper extending in a circumferential direction to the shaft body portion of the drilling member. There is a type in which a mating groove is formed periodically in the axial direction, and is provided with an engaging portion which can be disengaged by pressing an operation button while engaging with these engaging grooves.

[0003]

However, in the above-described conventional stopper for bone surgery, the stopper is engaged with or released from the shaft of the boring member.
In each case, it is necessary to keep pressing the operation button in order to operate the set screw or release the stopper from the engagement state of the perforated member with the shaft, so that the operability is not always good. There is a point.

In a stopper having a structure to be engaged by a set screw, if an engaging groove is formed in the shaft portion of the piercing member, it is difficult to know the position of the engaging groove. It is difficult to screw the set screw into the engagement groove, and if the engagement groove is not formed in the shaft portion, the set screw is screwed and the tip is brought into contact with the outer surface of the shaft portion. It is difficult to accurately set the position of the stopper, for example, the stopper is displaced in the axial direction at the time.

Further, in a stopper having a structure for releasing the engagement with the shaft portion by pressing the operation button, the shaft is turned in the opposite direction to the pressing operation based on the pressing operation of the operation button. A complicated interlocking mechanism is required to enable the operation of disengaging the engagement portion from the engagement groove of the body portion, which increases the manufacturing cost and increases the size of the stopper.

SUMMARY OF THE INVENTION Accordingly, the present invention is to solve the above-mentioned problem, and its object is to provide a simple internal structure and to engage an engaging portion with an engaging groove of a shaft portion of a piercing member. It is an object of the present invention to provide a bone surgery drilling stopper that can easily perform an operation for performing the drilling.

[0007]

According to the present invention, there is provided a bone surgery drilling stopper according to the present invention, wherein the bone surgery drilling stopper is mounted so as to be inserted through a shaft of a drilling member for drilling bone. A first member having a first shaft hole through which the shaft body portion can be inserted, the first member being a bone surgery drilling stopper configured to be positioned by engaging with an engagement structure formed in the first member; First
A second member configured to be screwable to a member and configured to communicate with the first shaft hole, the second member having a second shaft hole through which the shaft body portion can be inserted, and the first member Has the first
An opening facing the shaft hole is formed, and an engaging member is configured to protrude partially into the first shaft hole through the opening so as to be engageable with the engaging structure. An inclined surface portion inclined in a direction is formed, and whether or not the inclined surface portion presses the engaging member against the opening is determined by a screwing depth of the first member and the second member. It is characterized by comprising.

According to this invention, by changing the screwing depth of the first member and the second member, the engaging member is pressed against the opening by the inclined surface portion, and the engaging member protruding through the opening is perforated. It is possible to engage the engaging structure of the shaft portion of the member or release the state of pressing the engaging member by the inclined surface portion to release the engagement of the engaging member with the engaging structure of the shaft portion. it can. Therefore, it is possible to easily fix and release the position of the stopper with respect to the shaft portion of the perforated member simply by changing the screwing depth of the first member and the second member, thereby improving operability. Further, the engaging member is pressed against the opening by the inclined surface portion, and a part of the engaging member protruding through the opening is engaged with the engaging structure of the shaft portion. Since the ambiguity of the engagement state of the joining member is reduced, the engagement position of the stopper can be set accurately. Furthermore, since the internal structure related to the engagement / disengagement operation can be simplified, the manufacturing cost can be reduced and the size can be reduced. Here, it is desirable that at least the surface of the protruding portion of the engaging member is spherical, and it is particularly desirable that the engaging member is spherical. Preferably, the inclined surface is formed in a trumpet shape (tapered shape) so as to open in a screwing direction (axial direction) of the second member to the first member.

In the present invention, the first member is provided with the first shaft hole at a position axially away from the opening by an engagement cycle in the engagement structure or a natural number multiple of the engagement cycle. It is preferable that a movable engagement portion that is configured so as to be able to protrude and retract and that is urged in the protruding direction is provided. According to this means, the movable engagement portion urged in the direction protruding into the first shaft hole engages with the engagement structure of the shaft portion, thereby regulating the positional relationship between the shaft portion and the stopper. In this state, the engagement member can also be securely engaged with the engagement structure of the shaft portion, so that it is necessary to perform alignment between the engagement member and the engagement structure of the shaft portion. And the operability can be further improved. Here, it is desirable that at least the surface of the protruding portion of the movable engaging portion is spherical.

[0010] In the present invention, the relative rotation of the second member in the direction in which the screwed state of the first member and the second member is released may be brought into contact with the screwed portion of the first member. A stop member configured to prevent the first member and the second member is not separated from each other due to a contact between the stop member and the screw portion, and the engaging member is not escaped. Preferably, it is configured. According to this means, even when the second member is to be detached from the first member, the stop member attached to the second member is configured to be in contact with the screw portion (male screw portion or the like) of the first member. Due to this conflict, the second member cannot be removed from the first member, and the engagement member is configured not to escape from between the first member and the second member. It is possible to prevent the first member and the second member from being disassembled by mistake or the engaging member from coming off. Here, it is preferable that the stop member is attached by screwing in from the outside of the second member.

In the present invention, it is preferable that the first shaft hole has a substantially non-circular cross section. According to this means, if the first shaft hole has a non-circular cross section, the cross section of the shaft portion of the piercing member has a cross-sectional shape that matches the non-circular cross section of the first shaft hole. Can be configured so as not to rotate around the axis with respect to the shaft body, so that wear and deformation of the engaging member that engages with the engaging structure of the shaft body can be reduced. Here, as a specific mode in which the first shaft hole has a substantially non-circular cross section, the first shaft hole has a circular cross section, protrudes into the first shaft hole, and has an opening cross-sectional shape of the first shaft hole. It is desirable to attach to the first member an opening limiting member having a tip that can change the angle.

Next, a bone surgery piercing tool according to the present invention includes the above-described bone surgery piercing stopper, and a piercing member having the shaft portion inserted through the first shaft hole and the second shaft hole. It is provided. According to this boring device for bone surgery, the engaging structure of the shaft portion (preferably, the engaging grooves extending in the circumferential direction arranged in a plurality of cycles in the axial direction) and the engaging member can be easily engaged. , Which can be released, so that the positioning operation of the stopper can be easily performed, and since the internal structure is simple, it can be manufactured at a low cost.
Positioning accuracy can also be improved. Here, as the engagement structure formed in the shaft portion, an engagement groove having an open inclined side surface having a V-shaped cross section or a trapezoidal cross section extends in the circumferential direction, and the engagement groove has a constant pitch in the axial direction. It is desirable that they are arranged in a sequence.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a bone surgery drilling stopper and a bone surgery drilling tool according to the present invention. FIG. 1 is an exploded perspective view showing an entire piercing tool 100 including a stopper 10 and a reamer 20 (a piercing member) according to the present embodiment. Also, FIG.
FIG. 3 is an enlarged exploded cross-sectional view showing the structure of the stopper 10 in an enlarged manner.

The stopper 10 includes a bolt-shaped first member 11.
And a nut-shaped second member 12. First member 11
Has a head 11a having a circumferential uneven structure on the outer surface,
It comprises a cylindrical portion 11b extending in the axial direction from the head 11a and having a smaller diameter than the head 11a. A male screw portion 11c is formed on the outer peripheral surface of the cylindrical portion 11b. A shaft hole 11p having a circular cross section is formed inside the head 11a and the cylindrical portion 11b. On the wall surface of the cylindrical portion 11b, substantially circular openings 11d that open into the internal shaft hole 11p are formed at three locations set at equal angular intervals around the axis.

A recess 11e is formed in the head 11a of the first member 11 in a radial direction from the inner peripheral surface facing the shaft hole 11p. A stepped hole 11f penetrating the inside and outside of the head 11a is formed at a position shifted in the direction. The stepped hole 11f has a stepped portion 11g facing the outer peripheral side.

On the other hand, the second member 12 has an outer peripheral surface 12a having an uneven shape in the circumferential direction, and has a shaft hole 12p formed therein. A screw hole 12b penetrating through the shaft hole 12p is formed in the outer peripheral surface 12a. A female screw portion 12c is formed on the inner peripheral surface facing the shaft hole 12p.
2c is configured to be screwed into the male screw portion 11c of the first member 11. Also, of the inner peripheral surface facing the shaft hole 12p, a portion on the head 11a side of the first member 11 when screwed with the first member is inclined so as to open toward the head 11a. A tapered surface portion 12d is formed. The internal opening of the screw hole 12b facing the shaft hole 12p is formed near the boundary between the female screw portion 12c and the tapered surface portion 12d.

At the opening 11d of the first member 11, engagement balls 13 having an outer diameter larger than the opening diameter of the opening 11d are arranged from the outside. It is screwed into the male screw part 11c of the shape part 11b. FIG. 3 shows a state in which the female screw portion 12c is screwed into the male screw portion 11c.
As shown in (b), the engagement ball 13 is disposed between the opening 11d of the first member 11 and the tapered surface 12d of the second member 12.

At this time, since the set screw 16 is screwed into the screw hole 12b of the second member 12, the second member 12 is
The second member 12 cannot be removed from the first member 11 because the inner end of the set screw 16 is in contact with the male screw portion 11c even if the screw is rotated in the direction away from the member 11. Further, for the same reason, the engagement ball 13 is also prevented from escaping outside from between the first member 11 and the second member 12.

A ball plunger 14 is accommodated in a concave hole 11e facing the shaft hole 11p of the first member 11. An elastic member (not shown) (such as a coil spring) is accommodated in the ball plunger 14, and the ball 14a is urged by the elastic member so as to protrude. The ball 14a is configured to sink into the main body by receiving a stress from the inside that overcomes the elastic force of the elastic member.

Further, a screw member 15 is screwed into the stepped hole 11f of the first member 11. The screw member 15 has a step 15
b is screwed until the step 15b of the screw member 15 comes into contact with the step 11g of the stepped hole 11f, so that the flat distal end surface 15a of the screw member 15 is
It is configured to protrude into 1p.

As shown in FIG. 1, the reamer 20 has a cutting edge portion 21, a shaft portion 22, and a rear end portion 23.
A cutting blade 21a is formed at the distal end of the hole 1, and is inserted into the bone and rotated to process the inner surface of the hole. A plurality of engaging grooves 22c formed in the shaft portion 22 so as to extend in the circumferential direction on the outer peripheral surface of the portion near the rear end portion 23 are formed so as to be arranged in the axial direction at a constant pitch. . The engagement groove 22c has a trapezoidal cross section. That is, the groove shape has side portions inclined so as to open before and after in the axial direction, respectively, and a bottom portion between the side portions. However, the shape is not limited to such a groove shape, and may be a V-shaped cross-sectional shape or a concave cross-sectional shape. Also,
The outer surface of the shaft portion 22 is basically formed in a substantially cylindrical shape, but the portion near the rear end portion 23 of the shaft portion 22 is substantially the same as the formation range of the engagement groove 22c. 5, a flat portion 22d having a shape in which a part of the outer circumferential surface of the shaft portion 22 is removed is formed to extend in the axial direction.

The rear end portion 23 is connected to a rotating tool or a rotation driving source (not shown) and has a different shape having a plurality of flat surface portions in the circumferential direction for rotational driving. Reamer 2 above
A shaft hole that penetrates the entirety in the axial direction is formed in the inside of 0, and is configured so that a guide wire described later can be inserted into the shaft hole.

The surface of the flat portion 22d is formed almost flat. A plurality of scales or marks are formed on the flat portion 22d in an array along the axial direction of the shaft portion 22. These scales or marks are
This is for aligning the end faces of the head 11a of the first member 11 constituting the stopper 10 when it is set so as to be inserted into the shaft portion 22 of the reamer 20 as described later.
For example, the head 11a is placed on a scale formed on the flat portion 22d.
When the end faces are combined, in the method of use described later, the reamer 20 can be introduced into the bone only to the depth described on the combined scale, so that the tip does not enter a depth position higher than the depth. .

The stopper 10 is, as shown in FIG.
The shaft hole 11p of the first member 11 and the shaft hole 12 of the second member 12
It is used in a state where the shaft portion 22 of the reamer 20 is inserted through p. At this time, if the first member 11 and the second member 12 are screwed sufficiently deeply and the tapered surface portion 12d of the second member 12 presses the engagement ball 13 against the opening 11d, the engagement ball 13
Partially project through the opening 11d into the shaft hole 11p. As a result, the engagement groove 22d formed in the shaft body 22 is formed.
Is engaged with the engagement ball 13, and in this state, the stopper 10 is held in the axial direction of the shaft portion 22.

The engagement groove 22c also engages with the ball 14a of the ball plunger 14. Here, the projecting position of the ball 14a of the ball plunger 14 into the shaft hole 11p and the projecting position of the engaging ball 13 into the shaft hole 11p are exactly the engagement grooves formed in the shaft body portion 22. It is configured to match the formation pitch of 22c.

Further, the flat portion 22 d of the shaft portion 22 is formed on the distal end surface 15 of the screw member 15 attached to the first member 11.
It is configured so as to oppose a through a slight gap. Therefore, the distal end of the screw member 15 does not prevent the axial body portion 22 from moving in the axial direction, but since the flat distal end surface 15a of the screw member 15 is disposed inside the shaft hole 11p, In the shaft hole 11p, the shaft body portion 22 cannot rotate around the axis.

In this embodiment, by reducing the screwing depth of the second member 12 with respect to the first member 11, the tapered surface portion 12d does not press the engaging ball 13, and as a result, the engaging ball 13 The movement of the shaft portion 22 in the axial direction is not hindered. At this time, the ball plunger 1
4 is pressed against the outer peripheral surface of the shaft portion 22 by the elastic force, but the ball 14a is pushed back into the plunger body by the stress from the shaft portion 22, so that the stopper 10 is connected to the axis of the shaft portion 22. It can be moved in the direction with a click feeling. Further, since the ball 14a of the ball plunger 14 is engaged with the engaging groove 22c of the shaft portion 22 by elastic force, the stopper 10
The projection position of the ball 14a always matches the engagement groove 22c, and stops in the engaged state.

In such a state, the stopper 10 is moved along the outer peripheral surface of the shaft portion 22 of the reamer 20, and the stopper 10 is positioned at a desired position according to the scale or mark as described above. Then, the second member is screwed into the first member so that the stopper 10 is connected to the shaft portion 2.
2 can be fixed.

In this embodiment, for example, as shown in FIG. 4, the intramedullary nail 30 is introduced from the proximal end of the femur,
When screwing the lag screw 31 into the head of the femur through the inclined hole 30a formed at 0, it can be used for drilling a pilot hole for introducing the lag screw 31 in the femur.

In this case, the intramedullary nail 30 is inserted into the medulla through a perforation formed in the proximal end of the femur while being connected to the tip of the mounting arm 41 of the target device (positioning device) 40. . Support arm 4 of target device 40
2, a guide structure facing the inclined hole 30a is formed, and a sleeve 43 is guided and fixed to the guide structure. By passing through the inside of the sleeve 43 attached to the support arm 42, various implants and tools (guide wire, drill, reamer, etc.) including the lag screw 31 are accurately introduced toward the inclined hole 30a. You can do it.

Normally, a guide wire (not shown) is introduced into the femur along the sleeve 43, and the guide wire is passed through the shaft hole of the shaft portion 22, so that the reamer 20 of the above embodiment is removed. After being inserted through the sleeve 43 shown in FIG. 4, the cutting edge 21 is directed into the inclined hole 30 a of the intramedullary nail 30. At this time, by loosening the screwed state between the first member 11 and the second member 12, the stopper 10
Is made movable in the axial direction with respect to the shaft portion 22 of the reamer 20, and the end surface of the head 11a of the first member 11 is marked on a scale on a flat portion 22d of the shaft portion 22 in which a preset numerical value is written. Match. Then, by tightening the second member 12, the engagement ball 13 is pressed against the opening 11d by the tapered surface portion 12d, and the engagement ball 13 is engaged with the engagement groove 22c of the shaft portion 22. When the engagement state between the engagement ball 13 and the engagement groove 22c is held in a state where the engagement ball 13 is pressed by the tapered surface portion 12d, the stopper 10
Does not move at all in the axial direction.

In this state, T is attached to the rear end 23 of the reamer 20.
A wrench is connected and rotated to drive the reamer 20
The cutting edge portion 21 is guided into the bone along the guide wire, and forms a pilot hole for introducing the lag screw 31 shown in FIG. 4 through the inclined hole 30a. As the reamer 20 is introduced into the bone, the shaft 22 of the reamer 20 also moves toward the bone in the sleeve 43, and eventually,
When the cutting edge 21 reaches a preset depth, the end face of the head 11a of the first member 11 in the stopper 10 abuts on the end face of the base end 43a of the sleeve 43, and the cutting edge 21 is further inserted into the bone. It is regulated not to enter.

It should be noted that the bone surgery stopper and the bone surgery piercing tool of the present invention are not limited to the above-described illustrated examples, and that various changes can be made without departing from the gist of the present invention. Of course. For example, in the above embodiment, a case where a reamer is used as a piercing member is described. However, the present invention can be applied to various piercing tools such as a drill and a self-tapping screw in addition to the reamer.

[0034]

As described above, according to the present invention,
Only by changing the screwing depth of the first member and the second member, the position of the stopper with respect to the shaft of the perforating member can be easily fixed and released, so that the operability is improved. Further, the engaging member is pressed against the opening by the inclined surface portion, and a part of the engaging member protruding through the opening is engaged with the engaging structure of the shaft portion. Since the ambiguity of the engagement state of the joining member is reduced, the engagement position of the stopper can be set accurately. Furthermore, since the internal structure related to the engagement / disengagement operation can be simplified, the manufacturing cost can be reduced,
The size can be reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing the entire configuration of an embodiment of a bone surgery puncture device according to the present invention.

FIG. 2 is an exploded sectional view of the stopper according to the embodiment.

FIGS. 3A and 3B are a sectional view and a right side view showing an operation state of the stopper according to the embodiment.

FIG. 4 is a partial cross-sectional view showing a completed state of an operation for embedding an intramedullary nail in which the same embodiment can be used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Stopper 11 1st member 11b Tubular part 11c Male screw part 11d Opening 11p Shaft hole 12 Second member 12b Screw hole 12c Female screw part 12d Tapered surface part 12p Shaft hole 13 Engaging ball 14 Ball plunger 15 Screw member 16 Lock screw Reference Signs List 20 reamer 21 blade tip 22 shaft body 22c engagement groove 22d flat part 23 rear end

Claims (5)

[Claims] 1. A bone which is mounted so as to be inserted into a shaft portion of a drilling member for drilling a bone, and is configured to be positioned by engaging with an engagement structure formed on the shaft portion. A surgical drilling stopper, wherein the first shaft body portion can be inserted.
A first member provided with a shaft hole, and a second shaft hole configured to be screwable with the first member, configured to communicate with the first shaft hole, and capable of inserting the shaft body portion. An opening facing the first shaft hole is formed in the first member, and an engaging member partially projects into the first shaft hole through the opening to form the first member. Is configured to be engageable with the engagement structure,
An inclined surface portion inclined in the axial direction is formed on the second member, and the inclined surface portion presses the engaging member against the opening by a screwing depth between the first member and the second member. A puncture stopper for bone surgery, characterized in that it is configured to determine whether or not it is. 2. The method according to claim 1, wherein the first member includes:
At a position axially away from the opening by an engagement cycle of the engagement structure or a natural number multiple of the engagement cycle in the engagement structure, it is configured to be able to protrude and retract with respect to the first shaft hole and to be attached in a protruding direction. A piercing stopper for bone surgery, wherein a urged movable engaging portion is provided. 3. The first member according to claim 1, wherein the second member has a relative rotation operation in a direction in which the first member and the second member are disengaged from each other. A stop member configured to contact and hinder the screwing portion is attached, and the first member and the second member do not separate from each other due to the collision between the stop member and the screwing portion. A puncture stopper for bone surgery, wherein the joint member is configured not to escape. 4. The bone surgery stopper according to claim 1, wherein the first shaft hole has a substantially non-circular cross-section. 5. The bone surgical drilling stopper according to claim 1, further comprising: the shaft body portion inserted through the first shaft hole and the second shaft hole. A drill for bone surgery, comprising a drilling member.