TWI523634B - Bone fracture fixation device - Google Patents

Description

Bone marrow internal fixation device

The invention is applied to the field of fracture treatment, in particular to a medical auxiliary device which utilizes the characteristics of a shape memory alloy, automatically resets a fracture at the same time when fixing a fracture, saves the time of manual reduction, and improves the treatment effect of the fracture.

For patients with fractures, the main treatment method is to return the fracture to the normal position by external force, and then apply the fixation device, and let the affected part heal itself after a period of time. Because the treatment time is not short-lived, if the fixation is improper, it will seriously hinder the patient's daily activities. Therefore, how to effectively fix the affected part of the fracture? It is a very important research topic.

A common method of fracture fixation is to adopt an external fixation method, that is, a fixture is placed outside the limb to maintain the normal position of the limb. However, the external fixation method will produce an unnatural appearance in the operation area, affecting the daily activities of the patient. Even worse, the patient will be reduced in activity and the injured limb will be atrophied, thus creating an additional rehabilitation course.

Therefore, at present, for the treatment of fractures of long bones such as femur, humerus, ulna, tibia, and tibia, an internal fixation method with intramedullary needles has been developed. Because the intramedullary needle itself has the advantages of solid structure and firm fixation, it can replace most of the external fixation methods of fractures, which is beneficial to the early life of the injured limb. Move to reduce the need for rehabilitation in the future.

Regarding the fixing method of the intramedullary nail, the principle of three-point fixation is mainly used to provide support. Since the outer diameter of the intramedullary nail is too small to use the traditional locking method, the stability is insufficient. Therefore, the prior art is such as "System for intermedullary rod fixation and method" of US 2007/0100342, which has an intramedullary fixation device, which passes through an intramedullary fixation rod through several bone nails, and then presses the intramedullary fixation with a compression screw. Rod and bone nails for a stable combination. This prior art technique improves the fixation stability of the intramedullary nail, but the surgical procedure is quite complicated and difficult, so it is not a good solution.

Compared with the locking intramedullary nail, although the fixation effect is good, but the outer diameter is limited, the patient whose medullary cavity is too small cannot be used. Therefore, the prior art, such as the Chinese medical CN 2087948U "memory intramedullary needle with expansion and compression function", mainly includes a memory intramedullary needle with expansion and compression function, with open flaps and central ends The pressure flap can be pressed against the medullary cavity to achieve a stable fixation effect after being implanted into the body. The shape memory effect of the shape memory alloy is used to deform after being implanted into the body without using the fixed screw. A disadvantage of the prior art is that the pressure flap is fully erected and pressed against the wall of the medullary cavity to achieve a fixed fracture function, the compression portion including the fracture area, and the pressure flap has an opening; therefore, when the bone at the fracture When the bone cells are self-healing, the bone cells in the growth tend to enter the pressure flap opening and cover the intramedullary nail, so that the intramedullary nail cannot be taken out after the fracture is healed in the future.

In addition, for irregular bone fractures at the end of the human body, often because of the lack of appropriate fixation devices, only general nail fixation can be used, and the fixation effect is not good. Thus, conventional techniques such as the "Intramedullary fixation device for small bone fractures" of US 2009/0275946 include a fracture fixation device having a curvature and an end opening flap that can be inserted after implantation into the medullary cavity. The body temperature is heated to restore the original shape, and the shape memory effect of the memory alloy is used to deform and fix after implantation into the body, thereby producing a fixed fracture effect. Although the prior art is suitable for the fixation of irregular bones, it has only a slender rod and its anti-torsion ability is weak.

Obviously, all of the above-mentioned conventional techniques have their applied fracture states, but none of the prior art techniques can solve most of the problems, and it is necessary to improve them.

In view of this, the creators of this case have improved and innovated, and successfully developed and completed the bone marrow internal fixation device, which can provide a better patient fixation device for fracture patients.

The main object of the present invention is to provide an intramedullary fixation device which utilizes the shape memory property of a shape memory alloy to have good plasticity in a low temperature state, and is deformed after being heated to deform after being implanted in the medullary cavity of the fracture. The original form, at the same time the treatment of automatic fracture reduction. Then, the inner component is cooled down along the cavity of the hollow outer tube, and then heated to restore the complex shape, thereby generating the anchoring effect and increasing the anti-torsion function of the intramedullary nail mechanism.

Another object of the present invention is to provide an intramedullary fixation device that eliminates the need for a distal locking screw, eliminates the steps and time of implanting the locking screw, and reduces the wound to maintain aesthetics.

An intramedullary fixation device according to an embodiment of the present invention is disposed in a medullary cavity of a bone as an auxiliary treatment device for a fracture, and mainly comprises: a hollow outer tube, an inner component and a positioning member, the hollow outer tube The inner component is made of a shape memory alloy, and is implanted into the medullary cavity after being cooled in vitro, and then deformed by heating, so that the hollow outer tube and the inner component automatically reset the fracture of the bone, and the hollow outer tube The deformation of the inner component is pressed against the wall of the medullary cavity to produce a fixation effect.

The hollow outer tube is disposed in the medullary cavity, and one end of the hollow outer tube is provided with an abutting portion, the yoke portion is composed of a plurality of claw lobes, and the plurality of claw lobes are from one end of the hollow outer tube The center axis direction is split toward the other end, and the plurality of claws are pressed and heated to be pressed against the wall of the medullary cavity, and the other end of the hollow outer tube is provided with a pressing portion, and the pressing portion is composed of a plurality of connecting lobes. The plurality of connecting flaps are also pressed against the wall of the medullary cavity by heating, so that the urging portion and the pressing portion generate sufficient supporting force at both ends of the hollow outer tube, and the supporting portion and the pressing portion Between the bone engaging region, the bone engaging region is located at the fracture of the bone when it penetrates into the medullary cavity, and is used for correcting the fractured limb portion so that the number of connecting flaps of the pressing portion does not contact when opened. At the fracture site, the bone cells at the fracture are prevented from entering the space pressing portion of the connecting flap.

The hollow outer tube has a through hole at both ends thereof, and the inner component is inserted into the hollow outer tube by the cavity, and the inner component is provided with a riveting portion, and the riveting portion is composed of a plurality of claws And the plurality of claws are formed by splitting one end of the inner component along the central axis thereof toward the other end, and the through hole is provided with a through hole on the hollow outer tube, and the plurality of claws of the riveting portion The flap is opened by heating, and is inserted into the through hole and pressed against the wall of the medullary cavity.

The plurality of connecting lobes can openly surround a space, and the positioning member passes through the opened plurality of connecting lobes to limit the hollow outer tube to twist in the medullary cavity.

The hollow outer tube and the inner component are provided with a fixing hole, and the fixing hole is inserted with a fixing bolt to prevent the hollow outer tube from rotating relative to the inner component.

By the above description, the present invention utilizes the shape memory property of the shape memory alloy to have good plasticity in a low temperature state, allowing the hollow outer tube to pass through a fracture along a guiding steel wire, and is heated (for example, body temperature or non-contact). After the magnetic field is heated, it deforms and returns to its original shape. At the same time, the fractured limb is reset, and then the inner component is cooled down along the lumen of the hollow outer tube, and then heated to restore the complex shape, thereby creating an anchoring effect and increasing the anti-torsion function of the intramedullary nail mechanism.

10‧‧‧Bone marrow fixation device

1‧‧‧ hollow outer tube

11‧‧‧ cavity

12‧‧‧Resistance Department

13‧‧‧Pressing Department

14‧‧‧through holes

15‧‧‧Fixed holes

2‧‧‧Inside components

21‧‧‧ Riveting Department

22‧‧‧Fixed holes

3‧‧‧ Positioning parts

4‧‧‧ bones

41‧‧‧Mental cavity

42‧‧‧Fracture

5‧‧‧Guided steel wire

6‧‧‧Fixed bolt

16‧‧‧Bone joint area

121, 211‧‧‧ claws

131‧‧‧Connecting flap

S‧‧‧ Space

1 is a perspective exploded view of the present invention; FIG. 2 is a perspective sectional view of the present invention; FIG. 3 is a view showing an embodiment of the present invention;

In order to make the objects, technical solutions and advantages of the present invention more comprehensible, the present invention will be further described in detail with reference to the accompanying drawings.

As shown in FIG. 1 to FIG. 3, an intramedullary fixation device 10 according to the present invention is provided in a medullary cavity 41 of a bone 4 as an auxiliary treatment device for a fracture, which mainly comprises a hollow outer tube 1 An inner component 2 and a positioning component 3.

The hollow outer tube 1 and the inner component 2 are made of a shape memory alloy, and are implanted into the medullary cavity 41 after being cooled outside the body, and then deformed by heating to cause the hollow outer tube 1 and the inner component 2 to fracture the bone 4. The portion 42 is automatically reset, and the hollow outer tube 1 and the inner assembly 2 are deformed and pressed against the wall of the medullary cavity 41 to produce a fixing effect.

The hollow outer tube 1 is disposed in the medullary cavity 41, and the hollow outer tube 1 has a through-two The end channel 11 is for inserting the inner component 2. One end of the hollow outer tube 1 is provided with an abutting portion 12, which is composed of a plurality of claws 121, and the plurality of claws 121 are from one end of the hollow outer tube 1 toward the central axis thereof toward the other The claws 121 of the abutting portion 12 are heated and opened and pressed against the wall of the medullary cavity 41; the other end of the hollow outer tube 1 is provided with a pressing portion 13 which is composed of a pressing portion 13 The plurality of connecting petals 131 are formed on the other end of the hollow outer tube 1 with respect to the supporting portion 12, and the plurality of connecting petals 131 of the pressing portion 13 are also pressed by heating. The wall of the medullary cavity 41 is such that the urging portion 12 and the pressing portion 13 are at a proper distance from each other at the opposite ends of the hollow outer tube 1 to generate sufficient supporting force. The positioning member 3 extends through the hollow outer tube 1 for The hollow outer tube 1 is restricted from twisting within the medullary canal 41.

In addition, the abutment portion 12 and the pressing portion 13 have a bone engaging region 16 which is located at the fracture portion 42 of the bone 4 when penetrating into the medullary cavity 41 for correcting the fracture The limb portion does not contact the fracture portion 42 when the number of the connecting flaps 131 of the pressing portion 13 is opened, and the bone cells of the fracture portion 42 are prevented from entering the space of the plurality of connecting petals 131.

The inner assembly 2 is inserted into the hollow outer tube 1 by the cavity 11. The inner assembly 2 is provided with a riveting portion 21, which is composed of a plurality of claws 211, and the claws 211 The 211 is formed by splitting one end of the inner component 2 along the central axis thereof toward the other end, and the through hole 14 is disposed on the hollow outer tube 1 with a through hole 14 disposed on the bone. The portion of the rib portion 211 of the rivet portion 21 is heated and opened, and is stuck outside the through hole 14 to be pressed against the wall of the medullary cavity 41. on.

The plurality of connecting lobes 131 of the pressing portion 13 can openly surround a space S, the positioning member 3 passes through the opened space S, and the positioning member 3 protrudes from the opposite ends of the space In addition to S, the torsion resistance of the hollow outer tube 1 is increased to limit the hollow outer tube 1 in the medullary cavity 41 Reversed.

In addition, the inner component 2 protrudes through the through hole 14 via the caulking portion 21 and is pressed against the hollow outer tube 1 , and the fixing hole 15 is disposed on the other end of the hollow outer tube 1 at a position opposite to the through hole 14 . A fixing hole 22 is disposed on the other end of the inner component 2 with respect to the position of the riveting portion 21, such that the hollow outer tube 1 and the fixing hole 15, 22 of the inner component 2 are adjacent to the pressing portion 13, and are located on the bone Outside the junction area 16. The fixing hole 15 of the hollow outer tube 1 corresponds to the fixing hole 22 of the inner assembly 2, and is passed through the fixing hole 15, 22 of the hollow outer tube 1 and the inner assembly 2 by a fixing bolt 6 (Fig. 3). To further prevent the hollow outer tube 1 from rotating relative to the inner assembly 2.

The hollow outer tube 1 and the inner assembly 2 are made of a shape memory alloy, mainly made of nickel-titanium alloy, and the manufacturing process includes: 1. titanium-nickel alloy extraction control process; 2. pipe mechanical processing; 3. shape memory process processing ; and 4. Surface passivation treatment.

The intramedullary fixation device 10 required by the present invention can be completed by the aforementioned simple manufacturing process.

The surgical procedure for the intramedullary fixation device 10 of the present invention includes the following steps: Step 1. Lowering the hollow outer tube 1 and the inner assembly 2 to produce plasticity; Step 2. Passing a guiding steel wire 5 through the fracture portion 42; Step 3 The hollow outer tube 1 passes through the fracture portion 42 along the guiding steel wire 5; step 4. heating (for example, body temperature or non-contact magnetic field heating), the hollow outer tube 1 is deformed, and the hollow outer tube 1 is restored. Morphology, while reducing the bones of the bones of the fracture site 42; Step 5. The inner component 2 is implanted along the cavity 11 of the hollow outer tube 1 and heated to restore the complex shape to produce an anchoring effect; step 6. The insertion positioning member 3 is fixed and the anti-twist function is increased.

The intramedullary fixation device of the patent utilizes the shape memory property of the shape memory alloy, and the alloy can be easily plasticized after cooling, and returns to the appearance after heating, and has the following advantages:

1. Automatically reset the fracture, eliminating the need for manual reset time.

2. With the shape memory feature, you do not need to use the distal locking screw, eliminating the steps and time to insert the locking screw.

3. No need for distal locking screws to reduce the wound, in line with the principle of minimally invasive and aesthetic.

The detailed description of the preferred embodiments of the present invention is intended to be limited to the scope of the invention, and is not intended to limit the scope of the invention. The patent scope of this case.

10‧‧‧Bone marrow fixation device

1‧‧‧ hollow outer tube

11‧‧‧ cavity

12‧‧‧Resistance Department

13‧‧‧Pressing Department

14‧‧‧through holes

15‧‧‧Fixed holes

2‧‧‧Inside components

21‧‧‧ Riveting Department

22‧‧‧Fixed holes

3‧‧‧ Positioning parts

6‧‧‧Fixed bolt

16‧‧‧Bone joint area

121, 211‧‧‧ claws

131‧‧‧Connecting flap

S‧‧‧ Space

Claims (5)

An intramedullary fixation device for being disposed in a medullary cavity of a bone, the intramedullary fixation device comprising: a hollow outer tube having a cavity formed through the two ends thereof, the hollow outer tube having a support portion and a a pressing portion and a continuous hole extending through the wall of the tube, the supporting portion and the pressing portion are used for forcing the inner wall of the medullary cavity, and the bone engaging region is formed between the supporting portion and the pressing portion The bone engaging region is located at the fracture of the bone when penetrating into the medullary cavity, the through hole is disposed outside the bone engaging region; an inner component is disposed in the cavity of the hollow outer tube, the inner component a rivet portion is disposed on the outside of the through hole for urging the inner wall of the medullary cavity; and a positioning member is inserted through the hollow outer tube for limiting the hollow outer tube to the medulla In-cavity torsion; wherein the hollow outer tube and the inner component are tubular members made of a shape memory alloy, the hollow outer tube and the inner component are each provided with a fixing hole, and the fixing hole of the hollow outer tube corresponds to the a fixing hole of the inner component for receiving a fixing bolt, the hollow outer tube and the inner component Holes adjacent to the fixing portion is pressed against, and is positioned outside of the bone engagement region. The intramedullary fixation device according to claim 1, wherein the abutting portion is composed of a plurality of claws, and the plurality of claws are from one end of the hollow outer tube toward the central axis thereof toward the other One end is cracked. The intramedullary fixation device according to claim 2, wherein the pressing portion is composed of a plurality of connecting lobes formed at the other end of the hollow outer tube relative to the supporting portion, And the plurality of connecting lobes can openly surround a space, and the positioning member is disposed in the plurality of connecting lobes, and the locating members protrude from the two connecting lobes at opposite ends. The intramedullary fixation device according to claim 1, wherein the rivet portion is composed of a plurality of claws, and the plurality of claws are from one end of the inner component along a central axis thereof. The direction is split toward the other end, and the plurality of claws are stuck and extend beyond the through hole. The intramedullary fixation device of claim 4, wherein the through hole is adjacent to the abutting portion.