JP6248239B2 - External fixator for the treatment of finger joint fractures - Google Patents

Description

  The present invention relates to an external fixator for treatment in the case where a joint portion of a finger or its vicinity is broken.

  In the vicinity of the joint, a strong external force acts, so it is easy to fracture. The basics of fracture treatment is to fix the affected area, but it is better to move the joint as much as possible in terms of its function. However, it is not preferable to keep the joint surfaces in contact with each other because the fracture line extends to the joint surface in the fracture in the vicinity of the joint (so-called traction, it is better to keep the joint surfaces apart). Among these, those with the equipment coming out are called external fixators, and there are various types, but those shown in the following Patent Document 1 are well known.

In this method, a base called an attachment member is arranged on one side of a fractured joint, and a block called a pin support portion is slidably fitted into the joint, and the block is inserted into the bone and fixed to the bone. In this case, the attachment member can be bent. However, the structure is complicated as a whole, and fixing the pin support portion to a desired position of the attachment member is a difficult task (because it is a slide type). In addition, the pin support part is provided with two pins, but the pin support part is provided only on one side of the bone, and the pin is inserted only partway through the bone, so fixing is not possible. It is enough.

JP20041677062

The problem to be solved by the present invention is to provide an external fixator for treating a fracture of a finger joint, which can be easily operated with a simple structure, and can be finely adjusted to reliably perform its function.

Under the above-described problems, the present invention is a treatment tool for a case where a joint portion of a finger is fractured according to claim 1, wherein the treatment tool sandwiches the joint between the proximal phalanx and the middle phalanx or the middle phalanx. A first pin that passes through the proximal or middle phalanx at the proximal end is passed along both sides of the phalanx and the distal phalanx (the proximal phalanx and the distal phalanx in the thumb). A bolt with a screw formed on the outer periphery from the side and a long groove opened in the lateral direction at the center, and a second pin that is slidably fitted to the distal side of the bolt and penetrates the middle phalanx or the distal phalanx A ring that is passed through the long groove and penetrates in the lateral direction, a nut that is between the first pin and the second pin and screwed into the screw, and a coil spring that is fitted to the bolt between the nut and the ring. An external fixator for the treatment of fractures of the finger joints is provided.

In addition, the present invention is described above in claim 3, wherein the third pin is provided on the proximal side of the nut and penetrates the middle phalanx or the distal phalanx and the long groove. The distal end of the bolt is broken up and down and inserted into the ring, and the ring can be slid with the second pin passed through, but once inserted into the ring, the movement toward the proximal side beyond a certain level is restricted. The structure according to claim 4, wherein the locking structure is provided, and when the upper and lower sides of the bolt at the distal end side are pressed, this portion is elastically deformed so that the bolt can be pulled out of the ring. Provided is a configuration in which a movement (traction) for separating the first pin and the second pin can be performed even in a state where the proximal phalanx and the middle phalanx or the middle phalanx and the distal phalanx are bent.

According to the first aspect of the present invention, since it is based on a simple and reliable forward / backward stroke, which is a screw for traction, it can be manufactured at low cost and can reliably perform its function. In particular, since the adjustment is stepless with a screw, it can be pulled with the most favorable force for the medical condition. In addition, since the bolts supporting the pins are present on both sides of the bone, there is little tilting or sliding up to the side of the bone. According to the invention of claim 2, the tilting and sliding of the bone are further prevented. According to the invention of claim 3, the ring is prevented from falling off during assembly. According to the invention of claim 4, it can be used in many ways.

It is a perspective view of the external fixator of the present invention. It is a top view of the external fixator of the present invention. It is a top view which shows the use condition of the external fixator of this invention. It is a perspective view which shows the other use condition of the external fixator of this invention. It is a fragmentary sectional view of the other example which shows the combination of a volt | bolt and a ring.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of an external fixator (hereinafter referred to as an external fixator) for treating a finger joint fracture, and FIG. 2 is a plan view. 3 is a plan view when the external fixator is loaded on a finger. This external fixator has the following structure. The finger comprises the proximal phalanx 1, the middle phalanx 2 and the distal phalanx 3 from the proximal side (the thumb does not have the middle phalanx 2), and here the fractures were the proximal phalanx 1 and the middle phalanx. 2, and the middle phalanx 2 is pulled with respect to the proximal phalanx 1.

The configuration of the external fixator according to the present invention first includes bolts 4 arranged on both sides of the proximal phalanx 1 and the middle phalanx 2. A bolt 4a is formed on the outer periphery of the bolt 4, and a long groove 5 is formed in the central portion on the proximal end side so as to penetrate in the lateral direction and the crack is enlarged vertically at the distal end. Note that the screw 4a is formed only at the intermediate portion near the proximal end.

A hole 6a is formed in the side surface of the proximal end of the bolt 4, and the first pin 7 that penetrates the proximal phalanx 1 is inserted into the hole 6a. Note that one end of the first pin 7 (same for all pins) is pointed because it is necessary to penetrate the bone. The material of the bolt 4 is made of aluminum in order to increase the X-ray transmittance. A ring 8 is slidably fitted on the distal side of the bolt 4 (the portion cracked vertically). In this case, the long groove 5 has a sufficient length outside the ring 8 to prevent the bolt 4 from being bent, and naturally, the screw 4a does not exist in this portion. The second pin 9 also passes through the long groove 5 and is fixed to the ring 8 through the middle phalanx 2 (a hole 6b is formed therefor).

A nut 10 is screwed onto the screw 4 a of the bolt 4 (similarly where the middle phalanx 2 exists), and a coil spring 11 is wound around the outer periphery of the bolt 4 between the ring 8 and the nut 10. It has been. Further, the third pin 12 penetrates near the proximal end of the middle phalanx 2 near the proximal side of the nut 10 and passes through the long groove 5 of the bolt 4. This is near the joint and prevents the middle phalanx 2 from falling or sliding up.

Next, how to use the external fixator will be described. The ring 8, the nut 10, and the coil spring 11 are attached to the bolt 4 and are arranged on both sides of the bone sandwiching the joint, and the first to third pins 7, 9, 12 is passed. When the nut 10 is rotated toward the ring 8 in this state, the ring 8 is retracted and the action of the coil spring 11 is increased so that the middle phalanx 2 is pulled with respect to the proximal phalanx 1, and the proximal phalanx 1 And the middle phalanx 2 (joint) have a moderate gap. Since this traction force is due to tightening of the nut 10, it can be adjusted steplessly.

On the other hand, when the nut 10 is retracted from the ring 8 when it is tightened too much (when it is pulled too much), the tension of the coil spring 11 becomes weak (also stepless) and the gap becomes small. When all the pins 7, 9, and 12 are passed, the protruding portion is appropriately cut so that it does not get in the way by bending or covering the bolt 4. In particular, it is necessary to pay attention to the distance between adjacent fingers. The above is for the proximal phalanx 1 and the middle phalanx 2, but the same applies to the middle phalanx 2 and the distal phalanx 3. The same applies to the thumb.

From the above, the following can be said.
1) Good fixability and stability.
Since each pin is supported by two bolts on both sides, it does not tilt or slide up. In particular, the presence of the third pin is large.
2) Maintains joint function even during use.
When the bolt is rotated around the first pin, the distance between the second pin and the third pin does not change, so that the intermediate bone is bent with respect to the proximal bone. In this case, if the first pin and the hole through which the first pin is fitted are tightly fitted, the bending angle can be maintained.
3) The joint gap can be kept optimal.
Since it is a nut and screw system, an accurate gap can be secured. Fine adjustment is also possible.
4) Since aluminum that increases the X-ray transmittance is used as the material of the bolt, it does not significantly affect the X-ray imaging of the fractured part.

   The above is the basic form of the present invention, but the present invention may take various modified forms. For example, although the first pin to the third pin are from the proximal bone side, the reverse may be possible. In addition, it is preferable that the first pin and the bolt are fitted tightly, but if this is loose, it becomes unstable. In that sense, the pin and the hole may be fitted very tightly. However, when it is bent, the pin and the bone are rubbed and the bone is damaged, which is not preferable. Furthermore, since the ring may fall off from the bolt during assembly, it is necessary to pay sufficient attention.

FIG. 5 is a partial cross-sectional view of another example of the combination of the bolt 4 and the ring 8 in which the ring 8 does not easily fall off during assembly, but the cracked portion (tip portion 13) of the bolt 4 is formed into a slit shape. The hole 8a of the ring 8 is made smaller toward the distal side. Then, when the tip portion 13 is passed through the hole 8a, a locking structure 14 in which a step is formed on the inner side of the tip portion 13 or the like is provided so that the tip portion 13 is caught by the distal surface of the hole 8a and cannot be retracted. . Thus, once the bolt 4 is passed through the ring 8, it cannot be retracted from the portion where the locking structure 14 exists (advance is possible, and the traction force can be freely adjusted in that range).

However, since it is not good if it cannot be absolutely retracted, if the tip portion 13 is pinched with a finger, the tip portion 13 is lifted outward and the locking structure 14 is released. Although such a structure is not absolute, it is preferable to apply this configuration in all cases because it is unsanitary if the ring 8 falls down during assembly.

In addition, it is possible to pull the base phalanx 1 and the middle phalanx 2 (the distal phalanx 3) in a bent state. As shown in FIG. 4, the proximal phalanx 1 and the middle phalanx 2 (the distal phalanx 3) are bent, and in this state, the first pin 7 is moved along the bone axis of the proximal phalanx 1 (with the third pin 12 and (In the parallel direction). Furthermore, this external fixator can be applied to cases where it is not preferable to contact the joint surface due to diseases other than fractures, such as arthropathy and dislocation.

1 Basic phalanx 2 Middle phalanx 3 End phalanx 4 Bolt 4a ネ ジ screw 5 Long groove 6a Bolt hole through which the first pin passes
6b Ring hole 6c through which the second pin passes Bolt long groove 7 through which the third pin passes 1st pin 8 Ring 8a Hook hole 9 Second pin 10 Nut 11 Coil spring 12 Third pin 13 Tip portion 14 Locking structure

Claims (4)

  This is a treatment tool when the finger joint is broken, and this treatment tool is used for the proximal phalanx and the middle phalanx or the middle phalanx and the distal phalanx (the proximal phalanx and the distal phalanx in the thumb). A long groove that passes along the both sides and passes through the first pin that penetrates the proximal phalanx or the middle phalanx at the proximal end. A bolt formed by slidably fitted on the distal side of the bolt, a second pin penetrating the middle phalanx or the distal phalanx is passed through the long groove, and a first pin and the second pin An external fixator for treating a finger joint fracture, comprising: a nut between two pins and screwed into a screw; and a coil spring fitted to a bolt between the nut and the ring. The external fixator for treating a fracture of a finger joint according to claim 1, wherein a third pin is provided on the proximal side of the nut and penetrates the middle phalanx or the distal phalanx and the long groove. Although the ring can be slid with the distal end of the bolt cracked up and down and inserted into the ring and passed through the second pin, once it is inserted into the ring, it restricts the proximal movement beyond a certain level. 3. The external structure for treating a fracture of a finger joint according to claim 1 or 2, wherein a stop structure is provided and when the upper and lower sides of the distal end side of the bolt are pressed, this portion is elastically deformed and the bolt can be extracted from the ring. Fixator. The finger joint according to any one of claims 1 to 3, wherein the movement (traction) for turning the nut to separate the first pin and the second pin can be performed even in a state where the proximal phalanx and the middle phalanx or the middle phalanx and the distal phalanx are bent. External fixator for the treatment of bone fractures.