JP2603300B2 - Bone fixation device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bone fixing device used for fixing a fractured part or elongating a bone as an orthopedic surgical instrument.

[Conventional technology]

In general, when a bone is fractured, a bone fixing device as a surgical instrument is used to fix a fracture, and the bone fixing device is stretchable so as to adjust the elongation of the bone. Can also be used.

As shown in FIG. 8, the bone fixing device includes a telescopic body 70, and an adjusting screw mechanism 73 is provided outside the main body 70. The adjusting screw mechanism 73 has an adjusting knob.
74 are provided. At the left and right of the main body 70, a holding body 7
1, 72 are provided, and each holder 71, 72 has a pin support 75, 76.
Each of the pin supports 75, 76 holds a plurality of insertion pins 77,... 77 inserted into the bone 100.
The supports 75 and 76 for holding the insertion pins 77 and the holders 71 and 72 for supporting the supports are formed by ball joining.
The ball joint J is fixed by bolts b. The expansion and contraction of the main body 70 is also adjusted by the fixing bolt b.
Also in 6, the fastening state to the insertion pin 77 is adjusted by the fixing bolts b, b,... B.

In such a fixing device, the bolt b of the main body 70 is loosened, and the adjusting knob 74 is rotated to extend and contract the adjusting screw mechanism 73 to adjust the gap between the holding bodies 71 and 72. It is possible to loosen the fixing bolt b and loosen the ball joint J to move the supports 75 and 76 to a desired position around the ball joint J, thereby adjusting the position of the insertion pin with respect to the bone 100. Become.

[Problems to be solved by the invention]

However, in such a fixing device, since the connection between the holder and the support is performed by the ball joint J, when the fixing bolt b is loosened, the supports 75 and 76 move greatly to two three-dimensional positions. It is not preferable for bone stability. That is, when the positions of the supports 75 and 76 are determined, two positions are selected in the three-dimensional space, the fixing bolt b is first loosened, the support is moved to that position, and then the fixing bolt b is tightened. Since 75 and 76 are unstable, there is a problem that both the supports move while the fixing bolt b is being tightened, and the bone 100 cannot be stably fixed at a predetermined position.

In addition, the device can be operated to expand the interval between the affected parts 101 of the bone in accordance with the growth or elongation of the bone at regular intervals, but by rotating the adjustment knob while expanding and contracting the main body 70 while relying on intuition. I have. At this time, if the bone is excessively elongated, there is a risk of inducing complications. There was also a problem that it would. This is because the device does not have a mechanism capable of grasping an initial bone formation state that cannot be imaged by X-rays.

To complete the bone formation, at the final stage where the affected part has solidified, only the axial direction of the bone is free, and a natural load (muscular strength, weight, etc.) only in the axial direction is printed on the bone. Thus, techniques for giving more reliable bone formation have been reported. This technique is called dynamization. In this dynamization, it is necessary to select an appropriate time in the growth stage of the bone and to apply an appropriate load to the affected part 101. At this time, if the strength of the affected part 101 is insufficient, the affected part 101 is shrunk until the bones hit each other. There was a risk of getting rid of it. In the conventional fixing device, it is possible to perform dynamization by removing the outer adjustment screw mechanism 73 and loosening the fixing bolt b of the main body 70, but it is impossible to adjust the contraction amount limit. In addition, there is a problem that it is not possible to judge the timing of performing the dynamization, and it is necessary to perform the dynamization by intuition, so that accurate dynamization cannot be performed.

In view of the above, the present invention can stably and accurately perform the positioning of the bone, can accurately and safely grasp the growth state of the bone, and can accurately perform the dynamization. It is intended to provide a bone fixation device.

[Means for solving the problem]

Therefore, the present invention provides a main frame having linear rigidity and extending in the X-axis direction, and two holding members that are fixed to the main body frame so as to be position-adjustable and are inserted into bones extending in the Z-axis direction. A frame, a swinging plate that extends from the holding frame in the Y-axis direction and is swingable about an axis in the Z-axis direction of the holding frame, and is attached to the swinging plate and swings around the axis in the Y-axis direction. A pin head for detachably holding the insertion pin is provided, and a position adjusting mechanism for moving at least one of the two holding frames on the main body frame.

[Action]

Two holding frames holding the insertion pins are fixed to a main body frame having linear rigidity extending in the X-axis direction so as to be position-adjustable,
An oscillating plate is extended from the holding frame in the Y-axis direction, the oscillating plate is rotatable around an axis in the Z-axis direction, and an insertion pin inserted into a bone at the tip of the oscillating plate is detachable. Attach the pin head to be held. The pin head is swingable about an axis in the Y-axis direction at the tip of the swing plate. Thus, the two holding frames can be adjusted in position in the X-axis direction, the rocking plate can rotate around the axis in the Z-axis direction, and the pin head moves around the axis in the Y-axis direction at the tip of the rocking plate. It is rotatable, and can be independently adjusted for three axes centering on the movement in the X-axis direction, and the adjustment of the bone position is accurate and reliable, and its stability is increased.

Further, the bone fixing device includes a compression load detecting device for detecting a compression load applied to the holding frame via the insertion pin between the main body and the holding frame, and by continuously measuring the compression load. The state of bone growth can be accurately grasped, and the time for performing dynamization or the time for removing the fixing device from the affected part can be accurately grasped.

Further, at least one of the two holding frames is screwed into an adjusting screw, the adjusting screw moves the holding frame to a desired position on the body frame, and the holding frame is fixed to the body frame. The head of the adjusting screw is regulated by one end plate of the main body frame, and during the dynamizing operation, the adjusting screw is lifted from the end plate, and thereafter, a fixing device of the holding frame to the main body frame is provided. Loosen to open the holding frame. Then, a load is applied to the holding frame by the action of muscles or the like in a direction in which the insertion pins on both sides approach each other, and even if the affected part 101 is shortened, the holding frame stops in a state where the head of the adjustment screw is in contact with the end plate. . Thus, dynamization is performed without danger of a large amount of shortening. As described above, the maximum movement amount of the insertion pin in dynamization can be accurately regulated by the fixing device of the adjusting screw and the holding frame, and the end plate that regulates the movement of the adjusting screw.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

1 to 4, a bone fixing device 1 according to the present invention is shown.
Has a body frame 2 extending in the X-axis direction, and the body frame 2 is formed of four rigid slide bars 2a, 2a,... 2a. End plates 20 and 21 are provided at both ends of the body frame 2, and two holding frames 3a and 3b are slidably provided on the slide bar 2a. Guides are provided on both sides of the holding frame 3a on the left side in the figure. Plates 4, 4 are provided. Each of the guide plates 4 has a fixing plate
The fixing plate 4a is provided with fixing screws l, l. By tightening the fixing screws l, l, the fixing plate 4a is pressed against the side surface of the guide plate 4, and thus the holding frame 3a is positioned and fixed on the slide bar 2a.

The holding frame 3b is provided with guide plates 12, 12 on both sides thereof, and the guide plate 12 on the left side in FIG.
The fixing plate 13 is fixed to the fixing plate 13. The holding frame 3b is held between the end plate 21 and the fixed plate 13 so as to be able to slide by about 1 mm along the slide bar 2a.
A pressing member 31 is provided in the fixed plate 13, and the pressing member 31 is a load cell 30 provided in the guide plate 12.
Abut. The guide plate 12 of the holding frame 3b is
When the load cell 30 is pressed in the direction, the load cell 30 operates to measure the pressing force at this time, that is, the compressive load of the bone. The fixed plate
The connector 120 is provided on the side surface of the
Is connected to a recorder 17 via an amplifier 116. In this recorder 17, the state of the compressive load applied to the bone is
It is always displayed on the display device 19 at the top.

The main body frame 2 extends in the X-axis direction, and the holding frame 3a on the left side in the figure is position-adjusted and fixed at a position on the X-axis. This position adjustment is performed by a position adjustment mechanism 15, which has an adjustment screw 16, and the right end in the figure of the adjustment screw 16 is screwed into the lower part of the guide plate 4 of the holding frame 3a. ing. The adjusting screw 16 has a head 16a.
Is rotated, the holding frame 3a slides along the slide bar 2a. The adjusting screw 16 is connected to the end plate 20.
Extending through the stupid hole 40 (FIG. 5). As shown in FIGS. 2 and 3, a position measuring device 40 is provided near the left end of the slide bar 2a in the drawing, and the end of the telescopic bar of the position measuring device 40 is connected to the guide plate of the holding frame 3a. 4, the position measuring device 40 allows the position of the holding frame 3a to be accurately grasped at all times, so that the positions of the two bones 100, 100 can be accurately grasped.

Swing plates 5, 6 are held in the holding frames 3a, 3b so as to be able to swing around an axis in the Z-axis direction, respectively.
6 is locked by a locking mechanism 60 consisting of a fixing bolt 1 and a disk 10 on an axis around the Z-axis direction.
The rocking plates 5 and 6 project from the side surface of the main body frame 2 in the Y-axis direction, and pin heads 7 and 8 are attached to their ends. The pin heads 7, 8 hold a plurality of insertion pins P, P,... P inserted into the bones 100, 100 in a detachable manner. The pin heads 7 and 8 have fixing plates 9 and 110, respectively, and the fixing plates 9 and 110 removably press a plurality of insertion pins P against the main body side of the pin head by fixing bolts l, l,. These pin heads 7 and 8 are adapted to be rotatable around respective axes in the Y-axis direction, and the rotational movement about the Y-axis is locked by locking mechanisms 50 and 50 (FIG. 2). The lock mechanism 50 is provided with fixing bolts l, l,.
The lock mechanism 50 has the same mechanism as the lock mechanism 60 of the swing plates 5 and 6.

Next, a method of using the bone fixing device of the present invention will be described.

In FIG. 1, the insertion pins P are inserted into the bone on both sides of the affected part 101 of the bone 100, respectively. Then pin head 7,8
Then, the respective insertion pins P are fixed. Next, the adjusting screw 16 of the position adjusting mechanism 15 is rotated to move the holding frame 3a on the right side in the figure to a desired position while sliding on the slide bar 2a. After the holding frame 3a is moved to a desired position in this way, the fixing plate 4a of the holding frame 3a is fixed on the slide bar 2a by tightening the fixing bolts l, l. Next, the lock mechanisms 50 and 60 are respectively operated to adjust the rotational positions of the swing plates 5 and 6 in the Z-axis direction and the pin heads 7 and 8 in the Y-axis direction.

In this way, the bones 100, 100 are fixed so that a small space is created in the affected area 101 located between the left and right bones 100, 100.

As described above, in the X-axis direction, the holding frame 3a is moved to a predetermined position, and the movement of the holding frame in the X-axis direction, the movement of the rocking plate about the axis in the Z-axis direction, and the movement of the pin head in the Y-axis direction. Is performed independently, and the rocking plates 5, 6 held in the holding frames 3a, 3b do not not only move significantly, but also the pin head does not move significantly. Therefore, since the insertion pin does not largely move with respect to the axis on which the bone extends when adjusting, the positions of the bones 100, 100 on both sides can be accurately and stably adjusted, and when the position of the insertion pin is corrected, This can also be performed accurately without significant movement of the bone 100, and even in the final stage of bone formation, a slight correction of the position may be required. Further, since the fixing plates 4a, 4a are respectively attached to the guide plates of the holding frame,
Even if the adjusting screw of the position adjusting mechanism 15 is loosened, the holding frame
3a does not move and bone safety is reliably maintained.

When this device is set on both bones 100, 100, these two bones 10
The insertion pins P on both sides try to approach each other due to the muscles and muscles surrounding the 0,100. Therefore, at this time, the guide plate 12 of the right holding frame 3b comes into contact with the fixed plate 13 fixed firmly to the slide bar 2a, and a compressive load acts between these two members. The compression load is electrically returned by the load cell 30 to the amplifier 116 and output to the recorder 17 to be recorded. The recorder 17 always records the compressive load of the bone, and the state of growth of the bone is accurately grasped according to the state of the compressive load.

As shown in FIGS. 2 and 3, a position measuring device 40 is provided near the left end of the slide bar 2a in the drawing, and the end of the telescopic bar of the position measuring device 40 is connected to the guide plate of the holding frame 3a. 4
The position measuring device 40 allows the position of the holding frame 3a to be accurately grasped at all times, so that the positions of the two bones 100, 100 can be accurately grasped.

This bone fixing device can be used not only for fixing the bone at the time of the fracture but also for the purpose of extending the leg of a dwarf patient or the like.In this case, the bone growth state is always monitored while observing the bone growth state. By rotating the adjusting screw 16, the gap between the bones is gradually increased in accordance with the growth state, and thus the elongation of the bone can be promoted safely.

The rocking plates 5, 6 held in the holding frames 3a, 3b not only do not move significantly, but also the pin head does not move significantly, and therefore, can be inserted into the shaft where the bone extends. Since the pin does not move greatly during the adjustment, as shown in FIG. 6 and FIG.
Regardless of the direction in which the bone 100 is curved, the rotation of the pin heads 7 and 8 in the Y-axis direction or the rotation of the rocking plates 5 and 6
Correction can be performed correctly by rotation around the axis, and furthermore, adjustment of the position adjusting mechanism 15 enables extension of the bone even after correction. On the other hand, conventional bone correction cannot be performed only by the fixing device main body, but requires an adapter, and the adapter can perform correction in only one direction.

The recovery state of the affected part 101 of the bone and the growth state of the bone are different depending on the age difference or individual difference, but since this growth state or the recovery state is always detected by the detection member provided with the load cell 30, any The state of growth or recovery of the human bone can be accurately grasped, and the appropriate time of dynamization or the time of removing the external fixation device from the patient can be accurately grasped.

If the timing of the dynamization is accurately grasped,
The dynamization is performed as follows.

In FIG. 5, the adjusting screw 16 is screwed to the lower portion of the guide plate 4 of the holding frame 3a, and the adjusting screw 16 extends through the stupid hole 40 of the end plate 20 (FIG. 5a). Next, as shown in FIG. 5b, the head 16a of the adjusting screw 16 is rotated to lift the adjusting screw 16 from the end plate 20 by a distance W. In this state, if the fixing plate 4a of the holding frame 3a is loosened, the holding frame 3a
Can move together with the guide plate 4 to the right in the figure by a maximum W distance by a tensile load applied by a muscle or the like. As described above, if the adjusting screw 16 is lifted by the predetermined distance W in a state where no force is applied, the holding frame 3a can approach the opposing holding frame 3b by an appropriate distance. Thereby, dynamization is performed appropriately and safely. In dynamization, if there is a large displacement in which the stretched affected part contracts more than necessary, bone growth is rather hindered, but this device does not have such a risk.

〔The invention's effect〕

Since the present invention is configured as described above, the moving radius of the bone can be reduced, the bone can be corrected in two directions independently and independently for each axis, and the fixation and extension of the bone can be performed accurately and stably. It is possible to prevent excessive shortening at the time of dynamization, and furthermore, if a detection member is provided, the bone growth state can be accurately grasped at all times, and the timing of dynamization and the time of removing the fixing device can be accurately grasped. Play.

[Brief description of the drawings]

1 is a perspective view of the bone fixing device of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a side view thereof, FIG. 4 is a front view thereof, FIG. 6 and 7 are explanatory views of a bone correction state, and FIG. 8 is a front view of a conventional bone fixing device. 1 ... fixing device, 2 ... body frame, 3a, 3b ... holding frame, 4, 1
2 …… Guide plate, 5,6 …… Swing plate, 7,8 …… Pin head, 3
0: Load cell, 40: Position measuring device.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-81650 (JP, A) JP-A-59-203551 (JP, A) JP-A-62-32949 (JP, A) JP-A-63-63 139543 (JP, A)

Claims (2)

(57) [Claims] 1. A body frame having linear rigidity and extending in the X-axis direction, and two holding frames fixed to the body frame so as to be position-adjustable and holding insertion pins inserted into bones extending in the Z-axis direction. A swinging plate extending from the holding frame in the Y-axis direction and capable of swinging about the Z-axis in the holding frame; and being mounted on the swinging plate and swinging about the Y-axis direction. A bone fixing device, comprising: a pin head for detachably holding the insertion pin; and a position adjusting mechanism for moving at least one of the two holding frames on a main body frame. 2. The bone fixation device according to claim 1, wherein said bone fixation device includes a compression load detection device for detecting a compression load applied to the holding frame via an insertion pin.