JPH1057398A - Turn preventive device for operation of femur and humerus fracture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a turn preventive device easier and steadier to operate for the operation of fracture in a crural distal bone in which a turning resistance of distal bone to proximal bone is much more stable than that of the fracture part. SOLUTION: A hollow cylindrical cylinder nail 5 is inserted into the hollow inside of a tibia having fracture through a fracture part B by incising the knee. Into the hollow inside of the cylinder nail 5 is put sliding an anchor nail 7 made of shape-memory alloy such as Ti-Ni alloy having two legs 7b parallel to a nail body 7a. The legs 7b are put adjacent to the inside of a pair of openings 5a of the cylinder nail 5. The anchor nail 7 being warmed up by body heat or by warm water after putting in, accordingly the parallel legs 7b change their shape to outward V letter shape and bite into the inside of tibia cortex. Into the proximal end of the cylinder nail 5 is put a proximal anchor 12 made of shape-memory alloy, which also changes its shape and bites into the inside of tibia cortex. By this, the fractured part is simply and steadily kept free from turning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for preventing rotation of a thigh, an arm or the like, particularly a distal fracture of a lower leg, and more particularly to a fracture of a tibia, which is applied to a bone portion proximal to the fracture. The present invention relates to a surgical anti-rotation device for fixing both bone parts while preventing the bone parts distal to the rotation.

[0002]

BACKGROUND OF THE INVENTION Distal leg fractures, particularly distal tibia fractures (fractures of approximately one-third from the tip of the tibia), are the most frequent fractures, and if such fractures occur, A hollow cylindrical cylinder nail is inserted into the lumen of the tibia from the knee site to the distal side through the fracture site, and penetrated through the cylinder nail into the bone portion distal to the fracture site in the transverse direction of the tibia. A screw is driven to fix a bone proximal to and distal to a fracture site.

[0003] The known methods described above are effective for fixing bones proximal and distal to a fracture site,
In addition to the necessity of skin incision, since the driving of the screw in the transverse direction is performed while observing the transmission image by the X-ray, there is a problem that the amount of exposure to the X-ray increases and it is not technically simple.

[0004]

In order to solve this object, there has been proposed a surgical rotation preventing device disclosed in JP-A-8-103453. According to this known technique, the distal end of a hollow cylindrical cylinder nail that is inserted through the fracture from proximal to distal through the fracture is formed conically in the hollow interior of the fractured tibia, An opening is formed diametrically opposite the conical portion, and two Kirschna steel wires as anchor members are inserted from the proximal end into the hollow interior of the cylinder nail, and the curved tip of the Kirschna wire is connected to the cylinder nail. Are guided through each of the openings and protrude obliquely outside of the cylinder nail and are driven into the medial tibia cortex.

[0005] More specifically, in the operation of a fracture, a knee is incised, a cylinder nail is inserted into the lumen of the tibia from the proximal to the distal, and then the nail is again inserted into the tibia. Insert a Kirschna wire into the bore of the cylinder nail.
Kirschna steel wires are inserted one by one, and at this time, the bending direction of each of the Kirschna steel wires is directed toward the inner surface of the cylinder nail. As the insertion proceeds, the tip of each Kirschna steel wire slides while its tip is pressed against the inner surface of the cylinder nail, and when it reaches the opening of the conical part at the tip, the tip of the tip ends from the opening due to the elasticity of the pressing. Project outside. This protruding operation is likely to occur because the inner surface of the conical portion has a tapered surface. Then, in a state where each Kirschna steel wire is advanced most, both Kirschna steel wires are held with a bent portion at a proximal end thereof hooked on a concave portion at a proximal end of a cylinder nail, and further a tip of the Kirschna steel wire is held. The part protrudes well out of the opening and is driven into the bone cortex and secured thereto.

[0006]

In the above-described known anti-rotation tool for surgery, when it is mounted on an affected part as described above, two Kirschna steel wires having a curved portion at the tip are used. If the tip is oriented so that it faces the hollow inner wall of the cylinder nail and then is not inserted into the cylinder nail, the Kirschna steel wire tip will eventually become the distal end of the cylinder nail. And the Kirschna wire must be pushed distally through the hollow interior of the cylinder nail while deforming it somewhat against elasticity. Therefore, this operation is not easy, requires skill, and takes time.

[0007] Further, in this known surgical rotation preventing device,
As long as the rotational moment between the two ends is small, the resulting increase in the angle of rotation between the ends is relatively small and proportional. However, when the rotational moment exceeds a certain value, there is a problem that the inclination of the proportional curve becomes steep, and the turning angle sharply increases. This means that the proportional relationship between the rotation moment and the rotation angle is not good. The anti-rotation tool for surgery requires a good rotational moment and a proportional relationship between the rotation angle, and thus there is room for improvement in this respect. Furthermore, in the above-mentioned known anti-rotation tool for surgical operation, the Kirschna steel wire is loosely inserted inside the cylinder nail, so that the Kirschna wire may move inside the cylinder nail.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a simple and reliable method for performing an anti-rotation operation on an affected part in a short time, and furthermore, to obtain a rotational moment and a rotation. An object of the present invention is to provide a surgical rotation prevention device for a fracture of a thigh, an arm, or the like, which has a good angle proportional relationship and a stable holding of an anchor nail inside a cylinder nail.

[0009]

SUMMARY OF THE INVENTION According to the present invention, there is provided a hollow cylindrical cylinder nail which is inserted into the hollow interior of a fractured bone through the fracture from proximal to distal. A cylinder nail having an opening formed at a distal end thereof, and a cylinder nail inserted into the hollow interior of the cylinder nail from a proximal end thereof and having a tip portion passing through the opening of the cylinder nail. A surgical rotation prevention device for a fracture of a thigh, an arm, etc., comprising an anchor nail protruding into the inner side of the cortex and having a shape that allows the anchor nail to be inserted into a cylinder nail at a martensitic transformation temperature or lower. An anti-rotation device for surgery comprising a shape memory alloy that has been subjected to a shape memory process so that when the temperature exceeds the martensitic transformation temperature, the tip protrudes obliquely outside through the opening of the cylinder nail. Thus it is achieved.

The opening at the distal end of the cylinder nail is formed in the longitudinal direction of the cylinder nail at a position diametrically opposed.
The tip of the anchor nail is constituted by a pair of legs, which are parallel to each other and linear when the temperature is below the martensitic transformation temperature, and pass through the slot when the temperature exceeds the martensitic transformation temperature. Can be subjected to shape memory processing so as to open in a V-shape.

Further, at least the tip of the anchor nail may be formed of a shape memory alloy, and the shape memory alloy may be formed of a Ti—Ni alloy.

Further, at the proximal end of the cylinder nail,
A proximal anchor can be provided that is driven into the cortical media through the cylinder nail.

[0013]

Next, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, the tibia is denoted by the symbol S.
, The tibia S is shown as having a fracture site B at approximately one third of the lower leg. Then, as in the case of the above-described known example, the cylinder nail 5 is dissected from the knee portion on the upper side in the figure, so that the distal end (the end farther from the human body) from the proximal end (the end closer to the human body) of the tibia S. ) Is inserted into its lumen.

As shown in FIGS. 2 and 3, thighs, arms, etc.
In particular, the cylinder nail 5, which is a member of a surgical rotation prevention device for a fracture of a distal leg, is made of, for example, a Ti-Ni alloy and has a hollow cylindrical shape. Recess 2 is formed. The recess 2 has the shape of a slot in the long axis direction. At the proximal end of the cylinder nail 5, an opening 3 which is also long in the long axis direction is provided diametrically opposed. The opening 3, unlike the recess 2, is not open at the proximal end of the cylinder nail 5. As shown in FIG. 1, the cylinder nail 5 is slightly shorter than the length of the tibia, and its distal end or tip is formed in a conical surface as indicated by reference numeral 4 and becomes thinner toward the tip. A pair of openings 5a and 5a are formed in the distal end portion including the conical portion 4 so as to face each other in the diametrical direction. These openings 5a, 5a are in the form of slots in the longitudinal direction of the cylinder nail 5. As is clear from FIG. 2, the openings 5a, 5a are located at a position in line with the recess 2 in the longitudinal direction.

The surgical rotation preventing device further includes an anchor nail 7 shown in FIGS. 4 and 5. The anchor nail 7 has a main body 7a of a cylindrical rod material, and a small hole 8 is formed at a proximal end thereof. It is desirable that a portion having the small hole 8 is formed in a flat shape. 1 from the distal end of the main body 7a
A pair of parallel legs 7b integrally project toward the distal side. The proximal ends of the legs 7b are integral with each other and
The cross-sectional shape formed by the pair of legs 7b, 7b is a shape that can be slidably fitted into the internal space of the cylinder nail 5. The outer surface 9 at the distal end of the pair of legs 7b, 7b is a tapered surface, whereby the legs 7b, 7b
Has a sharp tip. The length of the anchor nail 7 is slightly shorter than the length of the cylinder nail 5 as will be understood from the description below. Further, a small hole 10 is formed at the base end of the pair of legs 7b, 7b, and this small hole 10 communicates with a space between the legs 7b, 7b through a slit 11. The small holes 10 and the slits 11 are provided for dispersing stress as described later.

According to the present invention, the anchor nail 7 is formed entirely of a shape memory alloy. The preferred shape memory alloy is a Ti-Ni alloy. This Ti—Ni alloy has been subjected to a solution treatment and a shape memory treatment so that the martensitic transformation temperature becomes close to, for example, a human body temperature. The legs 7b, 7b are at a temperature higher than the human body temperature, for example, 35 ° C.
At the above temperature, the parallel state shown in FIG. 4 opens in a V-shape shown in FIG.

FIGS. 7 to 9 show a proximal anchor 12 for use in the surgical anti-rotation device of the present invention. The proximal anchor 12 is integrally formed from a base 12a and a pair of parallel legs 12b, 12b, and a small hole 13 is formed in the base 12a.
And a slit 14 are formed. The small holes 13 and the slits 14 are also for preventing concentration of stress as described later. The proximal anchor 12 can also be formed of a shape memory alloy, for example, a Ti—Ni alloy, like the anchor nail 7. Then, as shown in FIG.
When the temperature of the proximal anchor 12 in which b is in a parallel state exceeds the martensitic transformation temperature, for example, a temperature of 35 ° C. or more, the legs 12b and 12b open in a V-shape as shown in FIG.

Next, a description will be given of a surgical method using the above-described surgical rotation preventing device of the present invention. First, in the case of a fracture of the distal part of the lower leg in the operation of a fracture, a portion of the knee is incised, and the cylinder nail 5 is shown by a solid line in FIG. Insert as follows. As a result, the cylinder nail 5 is located from the proximal side to the distal side of the fracture site B of the tibia S as shown in FIG. When the cylinder nail 5 occupies the position shown in FIG. 1, the anchor nail 7 is inserted into the lumen of the cylinder nail 5 from the same knee site. Before inserting the anchor nail 7 into the bore of the cylinder nail 5, the anchor nail 7 is immersed in cold water, for example, water at 0 ° C.
b and 7b are set in a parallel state. Also, the legs 7b, 7b of the anchor nail 7 should be aligned with the positions of the recesses 2, 2 of the cylinder nail 5 in the circumferential direction. Therefore, the state where the anchor nail 7 is being inserted into the lumen of the cylinder nail 5 from the proximal end to the distal side is as shown in FIG. In this state, a gap is formed between the main body 7a of the anchor nail 7 and the inner peripheral wall of the cylinder nail 5, and the outer peripheral surfaces of the legs 7b, 7b are in contact with and guided by the inner peripheral wall of the cylinder nail 5. When the anchor nail 7 is further pushed from the state of FIG. 10, the legs 7 b, 7 b come to be adjacent to the inside of the openings 5 a, 5 a at the distal end of the cylinder nail 5.

In this state, hot water having a temperature equal to or higher than the human body temperature, for example, hot water at 36 to 38 ° C., is circulated from the knee to the cylinder nail 5. As a result, the legs 7 of the anchor nail 7
b and 7b open in a V-shape in 4 to 5 seconds and deform outward as shown in FIG. It is possible to deform the legs 7b, 7b outward in a V-shape depending on the temperature of the human body without circulating hot water. And, by this deformation, the leg 7
The tips of b and 7b bite into the tibia portion distal to the fracture site B and are fixed. The state is as shown by a virtual line in FIG.

Next, the proximal anchor 12 shown in FIGS. 7 to 9 is applied as shown in FIG. That is, the proximal anchor 1 in the unopened state as shown in FIGS.
2 is inserted into the proximal end of the cylinder nail 5 from the knee portion so that its legs 12b are aligned with the positions of the recesses 2 and 2 of the cylinder nail 5, respectively. Accordingly, the proximal anchor 12 is subjected to the action of the warm water or the heat of the human body, and its legs 12b, 12b open in a V-shape as shown in FIG. Dig into the tibia S proximal to the fracture site B.

In this manner, the fracture portion B of the cylinder nail 5
Through the distal opening 5a, 5a with respect to the cylinder nail 5
Legs 7b, 7b bite into the tibia S, and the legs 12b, 12b restrained by the cylinder nail 5 bite into the tibia S through the recesses 2, 2 proximal to the fracture B of the cylinder nail 5. Therefore, the portion of the tibia S proximal to the fracture B and the portion of the tibia S distal to the fracture B are prevented from rotating with each other via the cylinder nail 5.

As described above, the anchor nail 7 is formed into a non-bent shape which is easy to insert into the hollow interior of the cylinder nail 5, then inserted into the hollow interior of the cylinder nail 5, and then exposed to the human body temperature. Legs 7b, 7b of anchor nail 7
Can be automatically opened. Thus, the legs 7b, 7b naturally protrude obliquely outward from the distal end of the cylinder nail 5 and bite into the bone cortex of the distal bone from the inside. Therefore, the anti-rotation device according to the present invention is simpler to operate than conventional ones, requires no skill, and is reliable.

The small holes 10 and the slits 11 of the anchor nails 7 are formed by moving the patient after the operation of feeding the tip of the legs 7b, 7b to the tibia S, and then moving the patient.
Even when repetitive stress is applied to the root of 7b, it is effective to prevent concentration of stress and prevent fatigue fracture of the legs 7b, 7b. The same effect is obtained for the small hole 13 and the slit 14 of the proximal anchor 12.

According to the experimental results, the above-mentioned Japanese Patent Application Laid-Open No. 8-103
In the known surgical anti-rotation device disclosed in Japanese Patent No. 453, the rate of increase of the rotation angle is low and stable up to a rotational moment of about 10 kg · cm, as shown by the curve A in FIG. In the rotational moment region, the increase in the rotation angle is remarkable. On the other hand, in the case of the present invention, FIG.
As shown by the curve B of FIG. 2, it can be recognized that the increase rate of the rotation angle does not have a large difference even in a high rotational moment region in a low rotational moment region. This means that in the case of the present invention, the proportional relationship between the rotational moment and the rotation angle is extremely good. Further, in the case of the present invention, as is apparent from FIG.
Is designed to slide smoothly without rattling in the cylinder nail 5, and therefore there is an advantage that disturbance of the rotation center position hardly occurs.

[0025] The surgical rotation preventing device is removed from the body after the bone is joined at the fracture site B. In this case,
First, the proximal anchor 12 is pulled out by operating through the opening 3 using the small hole 13 of the proximal anchor 12, and then the anchor nail 7 is operated through the opening 3 using the small hole 8, and the anchor nail 7 is pulled out. Then, the cylinder nail 5 is pulled out last. The present invention can be applied to not only the distal fracture of the lower leg but also other parts (the humerus, the femur, etc.).

[0026]

As described above, according to the rotation-preventing device of the present invention, at the time of surgery, a part such as a knee is incised and a cylinder is formed from a proximal part to a distal part in a lumen of a bone such as a tibia. Insert the nail, insert the anchor nail inside the cylinder nail, slide it, and when the tip reaches the tip of the cylinder nail, simply expose it to a temperature of about body temperature, the anchor nail legs will automatically It opens in a V-shape and penetrates into the bone cortex of the tibia from the inside to be fixed. Therefore, the operation is technically relatively simple and reliable, and the rotation prevention operation can be performed in a short time. In addition, the anti-rotation device of the present invention has a good proportional relationship between the rotation moment and the rotation angle, and can easily adopt a configuration in which disturbance of the position of the rotation center is unlikely to occur. Play an effect.

[Brief description of the drawings]

FIG. 1 is a view showing a state in which a surgical rotation preventing device for a fracture of a thigh, an arm or the like according to the present invention is applied to a fracture site.

FIG. 2 is a front view of a cylinder nail of the surgical rotation-preventing device shown in FIG. 1;

FIG. 3 is a sectional view of the cylinder nail shown in FIG. 2 as viewed from the right side.

FIG. 4 is a side view of an anchor nail of the surgical rotation-preventing device shown in FIG. 1;

FIG. 5 is a front view of the anchor nail of FIG. 4;

FIG. 6 is a side view showing a state where legs of the anchor nail of FIG. 4 are opened;

FIG. 7 is a side view of a proximal anchor.

FIG. 8 is a front view of a proximal anchor.

FIG. 9 is a side view showing a state where a leg of the proximal anchor is open.

FIG. 10 is a cross-sectional view showing a process during insertion of an anchor nail into a cylinder nail.

FIG. 11 is a cross-sectional view showing a state after an anchor nail is inserted into a cylinder nail, exposed to temperature, and its legs are opened.

FIG. 12 is a comparison diagram of the relationship between the rotation moment and the rotation angle of the surgical rotation prevention device.

[Explanation of symbols]

 S Tibial B Tibial fracture 2 Recess 3 Opening 4 Conical part 5 Cylinder nail 5a Opening 7 Anchor nail 7a Main body of anchor nail 7b Anchor nail leg 8 Small hole 12 Proximal anchor 12b Proximal anchor leg

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[Procedure amendment]

[Submission date] October 16, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

[Title of the Invention] An anti-rotation device for surgery for fractures of the thigh, upper arm, etc.

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to fractures of thighs, upper arms, etc.
In particular, the present invention relates to a surgical rotation prevention device for a distal fracture of a lower leg, particularly when a tibia is fractured, while preventing rotation of a distal bone portion relative to a bone portion proximal to the fracture portion, the both bone portions are prevented from rotating. The present invention relates to a surgical rotation preventing device for fixing a device.

[0002]

BACKGROUND OF THE INVENTION Distal leg fractures, particularly distal tibia fractures (fractures of approximately one-third from the tip of the tibia), are the most frequent fractures, and if such fractures occur, A hollow cylindrical cylinder nail is inserted into the medullary cavity of the tibia from the site of the proximal end of the tibia to the distal side through the fracture site, and penetrated through the cylinder nail into the portion of the bone distal to the fracture site. It has been practiced to drive transversely a screw to fix a bone proximal and distal to a fracture site.

[0003] The known methods described above are effective for fixing bones proximal and distal to a fracture site,
In addition to the necessity of skin incision, since the driving of the screw in the transverse direction is performed while observing the transmission image by the X-ray, there is a problem that the amount of exposure to the X-ray increases and it is not technically simple.

[0004]

In order to solve this object, there has been proposed a surgical rotation preventing device disclosed in JP-A-8-103453. According to this known technique, inside the medullary cavity of a broken tibia, the distal end of a hollow cylindrical cylinder nail inserted through the fracture from its proximal to distal is formed in a conical shape, An opening is formed diametrically opposite the conical portion, and two Kirschna steel wires as anchor members are inserted into the hollow interior of the cylinder nail from the proximal end thereof. It is guided into each of the openings of the nail, passes through it, projects obliquely outside the cylinder nail and is driven into the tibia cortex.

More specifically, in the operation of a fracture, a proximal part of the tibia is incised and a cylinder nail is inserted into the medullary cavity of the tibia from the proximal part to the distal part. Insert a Kirschna wire into the bore of the cylinder nail.
Kirschna steel wires are inserted one by one, and at this time, the direction of the curved tip of each Kirschna wire is directed toward the inner surface of the cylinder nail. As the insertion proceeds, the tip of each Kirschna steel wire slides while its tip is pressed against the inner surface of the cylinder nail, and when it reaches the opening of the conical part at the tip, the tip of the tip ends from the opening due to the elasticity of the pressing. Project outside. This protruding operation is likely to occur due to the conical tip of the cylinder nail. And
In the state where each Kirschna wire is advanced most, both Kirschna wires are held with the bent portion at the proximal end hooked on the concave portion at the proximal end of the cylinder nail, and the tip portion of the Kirschna wire is It protrudes sufficiently from the opening and is driven into the inner side of the cortex and fixed thereto.

[0006]

In the above-described known anti-rotation tool for surgery, when the above-mentioned anti-rotation tool is attached to an affected part as described above, two Kirschna steel wires having a curved portion are used. If the tip is oriented so that it faces the hollow inner wall of the cylinder nail and is not inserted into the cylinder nail, the Kirschna wire tip will eventually be opened at the distal end of the cylinder nail. And the Kirschna wire must be pushed distally through the hollow interior of the cylinder nail while deforming it somewhat against elasticity. Therefore, this operation is not easy, requires skill, and takes time.

[0007] Further, in this known surgical rotation preventing device,
As long as the rotational moment between the two ends is small, the resulting increase in the angle of rotation between the ends is relatively small and proportional. However, when the rotational moment exceeds a certain value, there is a problem that the inclination of the proportional curve becomes steep, and the turning angle sharply increases. This means that the proportional relationship between the rotation moment and the rotation angle is not good. The anti-rotation tool for surgery requires a good rotational moment and a proportional relationship between the rotation angle, and thus there is room for improvement in this respect. Furthermore, in the above-mentioned known anti-rotation tool for surgical operation, the Kirschna steel wire is loosely inserted inside the cylinder nail, so that the Kirschna wire may move inside the cylinder nail.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a simple and reliable method for performing an anti-rotation operation on an affected part in a short time, and furthermore, to obtain a rotational moment and a rotation. An object of the present invention is to provide an anti-rotation device for a surgical operation for a fracture of a thigh, an upper arm or the like, which has a good angle proportional relationship and a stable holding of an anchor nail inside a cylinder nail.

[0009]

According to the present invention, the object is to provide a hollow cylindrical cylinder nail which is inserted into the medullary cavity of a fractured bone through the fracture from its proximal to distal end. A cylinder nail having an opening formed at a distal end thereof, and a cylinder nail inserted into the hollow interior of the cylinder nail from a proximal end thereof and having a tip portion passing through the opening of the cylinder nail. In a surgical rotation prevention device for a fracture of a thigh, an upper arm, or the like, comprising an anchor nail protruding outside and being driven into the inner side of a cortex, the anchor nail can be inserted into a cylinder nail at a martensite reverse transformation end temperature or lower. It has a shape and is made of a shape memory alloy that has been subjected to a shape memory process so that when the temperature exceeds the martensite reverse transformation end temperature, the tip portion projects obliquely outside through the opening of the cylinder nail. It is accomplished by the operator for rotation preventer.

The opening at the distal end of the cylinder nail is formed in the longitudinal direction of the cylinder nail at a position diametrically opposed.
The tip of the anchor nail is constituted by a pair of legs.The legs are parallel to each other at a temperature below the martensitic reverse transformation end temperature, and form a straight line. V through the slot
Shape memory processing may be performed so as to open in a character shape.

Further, at least the tip of the anchor nail may be formed of a shape memory alloy, and the shape memory alloy may be formed of a Ti—Ni alloy.

Further, at the proximal end of the cylinder nail,
A proximal anchor can be provided that is driven into the cortical media through the cylinder nail.

[0013]

Next, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, the tibia is denoted by the symbol S.
, The tibia S is shown as having a fracture site B at approximately one third of the lower leg. Then, as in the case of the above-described known example, the cylinder nail 5 is dissected from the knee portion on the upper side in the figure, so that the distal end (the end farther from the human body) from the proximal end (the end closer to the human body) of the tibia S. ) Is inserted into the medullary cavity.

As shown in FIGS. 2 and 3, a cylinder nail 5, which is one member of a surgical rotation prevention device for a fracture of a thigh, an upper arm, etc., particularly a distal leg, is made of, for example, a Ti-Ni alloy and has a hollow cylindrical shape. None, a pair of diametrically opposed recesses 2 are formed at its proximal or proximal end. The recess 2 has the shape of a slot in the long axis direction. At the proximal end of the cylinder nail 5, an opening 3 which is also long in the long axis direction is provided diametrically opposed. The opening 3, unlike the recess 2, is not open at the proximal end of the cylinder nail 5.
As can be seen from FIG. 1, the cylinder nail 5 is slightly shorter than the length of the tibia, and its distal end or tip is formed as a conical surface as indicated by reference numeral 4 and becomes thinner toward the tip. A pair of openings 5a and 5a are formed in the distal end portion including the conical portion 4 so as to face each other in the diametrical direction. These openings 5a, 5a are in the form of slots in the longitudinal direction of the cylinder nail 5. As is clear from FIG. 2, the openings 5a, 5a are located at a position in line with the recess 2 in the longitudinal direction.

The surgical rotation preventing device further includes an anchor nail 7 shown in FIGS. 4 and 5. The anchor nail 7 has a main body 7a of a cylindrical rod material, and a small hole 8 is formed at a proximal end thereof. It is desirable that a portion having the small hole 8 is formed in a flat shape. 1 from the distal end of the main body 7a
A pair of parallel legs 7b integrally project toward the distal side. The proximal ends of the legs 7b are integral with each other and
The cross-sectional shape formed by the pair of legs 7b, 7b is a shape that can be slidably fitted into the internal space of the cylinder nail 5. The outer surface 9 at the distal end of the pair of legs 7b, 7b is a tapered surface, whereby the legs 7b, 7b
Has a sharp tip. The length of the anchor nail 7 is slightly shorter than the length of the cylinder nail 5 as will be understood from the description below. Further, a small hole 10 is formed at the base end of the pair of legs 7b, 7b, and this small hole 10 communicates with a space between the legs 7b, 7b through a slit 11. The small holes 10 and the slits 11 are provided for dispersing stress as described later.

According to the present invention, the anchor nail 7 is formed entirely of a shape memory alloy. The preferred shape memory alloy is a Ti-Ni alloy. This Ti—Ni alloy has been subjected to a solution treatment and a shape memory treatment so that the martensite reverse transformation end temperature is close to, for example, the temperature of a human body. At a temperature higher than the human body temperature, for example, at a temperature higher than 35 ° C., the legs 7b are opened from the parallel state shown in FIG. 4 to the V shape shown in FIG.

FIGS. 7 to 9 show a proximal anchor 12 for use in the surgical anti-rotation device of the present invention. The proximal anchor 12 is integrally formed from a base 12a and a pair of parallel legs 12b, 12b, and a small hole 13 is formed in the base 12a.
And a slit 14 are formed. The small holes 13 and the slits 14 are also for preventing concentration of stress as described later. The proximal anchor 12 can also be formed of a shape memory alloy, for example, a Ti—Ni alloy, like the anchor nail 7. Then, as shown in FIG.
When the temperature of the proximal anchor 12 in which b is in a parallel state exceeds the martensitic reverse transformation end temperature, for example, a temperature of 35 ° C. or more, the legs 12b, 12b open in a V-shape as shown in FIG. I have.

Next, a description will be given of a surgical method using the above-described surgical rotation preventing device of the present invention. First, in the case of a fracture at the distal part of the lower leg during the operation of the fracture, a portion of the proximal end of the tibia is incised, and the cylinder nail 5 is inserted into the medullary cavity of the tibia S from the proximal to the distal side in FIG. Insert as shown by the solid line.
As a result, the cylinder nail 5 is moved to the tibia S as shown in FIG.
Will be located from the proximal side to the distal side of the fracture site B. When the cylinder nail 5 occupies the position of FIG. 1, the anchor nail 7 is inserted into the lumen of the cylinder nail 5 from the same proximal end of the tibia. Before the anchor nail 7 is inserted into the bore of the cylinder nail 5, the anchor nail 7 is immersed in low-temperature water, for example, water at 0 ° C., so that the legs 7b are parallel. Also, the legs 7b, 7b of the anchor nail 7 should be aligned with the positions of the recesses 2, 2 of the cylinder nail 5 in the circumferential direction. Therefore, the state where the anchor nail 7 is being inserted into the lumen of the cylinder nail 5 from the proximal end to the distal side is as shown in FIG. In this state, a gap is formed between the main body 7a of the anchor nail 7 and the inner peripheral wall of the cylinder nail 5, and the outer peripheral surfaces of the legs 7b, 7b are in contact with and guided by the inner peripheral wall of the cylinder nail 5. FIG.
When the anchor nail 7 is further advanced from the state of 0, the leg 7
b, 7b will be adjacent to the inner starting point of the opening 5a, 5a at the distal end of the cylinder nail 5.

In this state, the cylinder nail 5 is heated from the site at the proximal end of the tibia to a temperature higher than the human body temperature, for example, 36-3.
Circulate warm water at 8 ° C. Thereby, the anchor nail 7
The legs 7b, 7b open in a V-shape in 4 to 5 seconds and deform outward as shown in FIG. It is possible to deform the legs 7b, 7b outward in a V-shape depending on the temperature of the human body without circulating hot water. Then, due to this deformation, the tips of the legs 7b, 7b bite into the tibia portion distal to the fracture site B and are fixed. The state is as shown by a virtual line in FIG.

Next, the proximal anchor 12 shown in FIGS. 7 to 9 is applied as shown in FIG. That is, the proximal anchor 1 in the unopened state as shown in FIGS.
2 is inserted into the proximal end of the cylinder nail 5 from the proximal end of the tibia so that its legs 12b are aligned with the positions of the recesses 2 and 2 of the cylinder nail 5, respectively. This allows
The proximal anchor 12 is subjected to the action of the warm water or the heat of the human body, and its legs 12b, 12b open in a V-shape as shown in FIG. Penetrates into the proximal side of the fracture site B.

In this manner, the fracture portion B of the cylinder nail 5
Through the distal opening 5a, 5a with respect to the cylinder nail 5
Legs 7b, 7b bite into the tibia S, and the legs 12b, 12b restrained by the cylinder nail 5 bite into the tibia S through the recesses 2, 2 proximal to the fracture B of the cylinder nail 5. Therefore, the portion of the tibia S proximal to the fracture B and the portion of the tibia S distal to the fracture B are prevented from rotating with each other via the cylinder nail 5.

As described above, the anchor nail 7 is formed into a non-bent shape which is easy to insert into the hollow interior of the cylinder nail 5, then inserted into the hollow interior of the cylinder nail 5, and then exposed to the human body temperature. Legs 7b, 7b of anchor nail 7
Can be automatically opened. Thus, the legs 7b, 7b naturally protrude obliquely outward from the distal end of the cylinder nail 5 and bite into the bone cortex of the distal bone from the inside. Therefore, the anti-rotation device according to the present invention is simpler to operate than conventional ones, requires no skill, and is reliable.

The small holes 10 and the slits 11 of the anchor nails 7 are formed by moving the patient after the operation of feeding the tip of the legs 7b, 7b to the tibia S, and then moving the patient.
Even when repetitive stress is applied to the root of 7b, it is effective to prevent concentration of stress and prevent fatigue fracture of the legs 7b, 7b. The same effect is obtained for the small hole 13 and the slit 14 of the proximal anchor 12.

According to the experimental results, the above-mentioned Japanese Patent Application Laid-Open No. 8-103
In the known anti-rotation device for operation disclosed in Japanese Patent No. 453, the rate of increase of the rotation angle is low and stable up to a rotation moment of about 10 kg · cm, as shown by the curve A in FIG. In the rotational moment region, the increase in the rotation angle is remarkable. In contrast, according to the present invention,
As shown by the curve B in FIG. 12, it is recognized that the rate of increase of the rotation angle has no significant difference between the high rotational moment region and the low rotational moment region. This means that in the case of the present invention, the proportional relationship between the rotational moment and the rotation angle is extremely good. Further, in the case of the present invention, as is apparent from FIG. 11, the anchor nail 7 slides smoothly without rattling in the cylinder nail 5, so that the rotation center position is less likely to be disturbed. There is.

[0025] The surgical rotation preventing device is removed from the body after the bone is joined at the fracture site B. In this case,
First, the proximal anchor 12 is pulled out by operating through the opening 3 using the small hole 13 of the proximal anchor 12, and then the anchor nail 7 is operated through the opening 3 using the small hole 8, and the anchor nail 7 is pulled out. Then, the cylinder nail 5 is pulled out last. The present invention can be applied to not only the distal fracture of the lower leg but also other parts (the humerus, the femur, etc.).

[0026]

As described above, according to the rotation-preventing device of the present invention, at the time of surgery, a site such as the proximal end of the tibia is incised, and the region from the proximal end to the distal end is introduced into the medullary cavity of the bone such as the tibia. Insert the cylinder nail into the cylinder nail, insert the anchor nail inside the cylinder nail and slide it.When the tip reaches the tip of the cylinder nail, simply expose it to a temperature of about body temperature. It automatically opens in a V-shape and enters the tibia bone cortex from the medial side and is fixed. Therefore, the operation is technically relatively simple and reliable, and the rotation prevention operation can be performed in a short time. In addition, the anti-rotation device of the present invention has a good proportional relationship between the rotation moment and the rotation angle, and can easily adopt a configuration in which disturbance of the position of the rotation center is unlikely to occur. Play an effect.

[Brief description of the drawings]

FIG. 1 is a view showing a state in which a surgical rotation preventing device for a fracture of a thigh, an upper arm or the like according to the present invention is applied to a fracture site.

FIG. 2 is a front view of a cylinder nail of the surgical rotation-preventing device shown in FIG. 1;

FIG. 3 is a sectional view of the cylinder nail shown in FIG. 2 as viewed from the right side.

FIG. 4 is a side view of an anchor nail of the surgical rotation-preventing device shown in FIG. 1;

FIG. 5 is a front view of the anchor nail of FIG. 4;

FIG. 6 is a side view showing a state where legs of the anchor nail of FIG. 4 are opened;

FIG. 7 is a side view of a proximal anchor.

FIG. 8 is a front view of a proximal anchor.

FIG. 9 is a side view showing a state where a leg of the proximal anchor is open.

FIG. 10 is a cross-sectional view showing a process during insertion of an anchor nail into a cylinder nail.

FIG. 11 is a cross-sectional view showing a state after an anchor nail is inserted into a cylinder nail, exposed to temperature, and its legs are opened.

FIG. 12 is a comparison diagram of the relationship between the rotation moment and the rotation angle of the surgical rotation prevention device.

[Description of Signs] S Tibial B Tibial Fracture 2 Recess 3 Opening 4 Conical 5 Cylinder Nail 5a Opening 7 Anchor Nail 7a Main Body of Anchor Nail 7b Anchor Nail Leg 8 Small Hole 12 Proximal Anchor 12b Proximal Anchor Leg

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2

Claims (4)

[Claims] A hollow cylindrical cylinder nail inserted into a hollow part of a fractured bone from a proximal part to a distal part through a fractured part, and an opening is formed at a distal end thereof. A cylinder nail that is inserted into the hollow interior of the cylinder nail from its proximal end,
And an elongated anchor nail whose tip projects obliquely outside the cylinder nail through the opening of the cylinder nail and is driven into the inner side of the cortical bone. However, below the martensite transformation temperature, it has a shape that can be inserted into the cylinder nail, and when it exceeds the martensite transformation temperature, it is subjected to shape memory processing so that the tip protrudes obliquely outside through the opening of the cylinder nail. An anti-rotation device for surgery, comprising a shape memory alloy. 2. A cylinder nail having a distal end opening formed in a longitudinal direction of the cylinder nail at a position diametrically opposed.
It consists of a pair of slots.
It has a pair of legs, and these legs are subjected to shape memory processing so as to be parallel and linear to each other below the martensitic transformation temperature, and to open in a V-shape through the slot above the martensitic transformation temperature. The surgical anti-rotation device according to claim 1, wherein: 3. The surgical anti-rotation device according to claim 1, wherein at least a tip portion of the anchor nail is made of a shape memory alloy, and the shape memory alloy is a Ti—Ni alloy. 4. A surgical convolution according to claim 1, 2 or 3, wherein a proximal anchor is provided at the proximal end of the cylinder nail, which is driven into the cortex through the cylinder nail. Protective gear.