WO1999048414A2

WO1999048414A2 - Fracture external fixator

Info

Publication number: WO1999048414A2
Application number: PCT/KR1999/000122
Authority: WO
Inventors: Hong Jun Han
Original assignee: Hong Jun Han
Priority date: 1998-03-21
Filing date: 1999-03-19
Publication date: 1999-09-30
Also published as: KR19990075902A; WO1999048414A3; KR100271670B1

Abstract

The purpose of this invention which is about fracture external fixation is to settle an inconvenience and a restriction of patients' action caused in conventional ring fixators and unilateral fixators. This invention is composed of a rod (1), a ring (2) of an arch shape, a rod-to-ring clamp (3) for joining the rod (1) with the ring (2), a half-pin (5) for fixing a fracture portion, being stuck in the bone, a pin-to-rod clamp (6) for joining and fixing the half-pin (5) to the rod (1), a pin-to-ring clamp (7) for fastening the half-pin (5) into the hole (2a) of the ring (2), to thereby enable to simultaneously perform the ring fixation and unilateral fixation methods through a mutual combination among component elements and to execute a mutual change of the unilateral fixation and the ring fixation according to a union progress state of the fracture. Such construction in the fracture external fixator provides a free change from the unilateral fixation into the ring fixation or from the ring fixation into the unilateral fixation, and also furnishes an optimum fixation method through a use of the minimum instruments, resulting in minimizing the patient's inconvenience, remarkably reducing the patient's pain caused by its putting-on and his active restriction in comparison with the conventional external fixator, and providing the fixator with a neat external shape.

Description

DESCRIPTION

FRACTURE EXTERNAL FIXATOR

Technical Field

The present invention relates to a fracture external fixator capable of effectively performing a fracture external fixation operation by combining ring fixation and unilateral fixation; and, more particularly, to a fracture external fixator capable of operation in a hybrid type of a ring fixation and a unilateral fixation, the fracture external fixator being composed of a rod, a ring of an arch shape having numerous holes piercing through its upper and lower surface, a rod-to-ring clamp for joining the rod with the ring, a ring-to-ring clamp for combining and fixing the ring and the ring, a pin for fixing a fracture region, being stuck in the bone, a pin-to-rod clamp for joining and fixing the pin to the rod, a rod-to-rod clamp for connecting the rod to the rod, and a pin-to-ring clamp for combining and fixing the pin into the hole of the ring.

Background Art

A fracture unilateral fixation device is a device for recovering an original state from a fracture state by fixing and correcting a region displaced by fracture on an outer side of the fracture.

In a former fracture external fixation device, there are well-known a unilateral pin fixator, a ring fixator and a hybrid type external fixator of the unilateral fixation and the ring fixation.

In a basic concept of the unilateral pin fixator, a thick iron rod. a pin and a clamp fixing the pin to the iron rod are used, in order to attain a remedy recovery effect from a fracture displaced portion by fixing the fracture portion on its outer side. In other words, since the pin is set in the rod standing perpendicularly so as to fix the bone, in case that a fracture region is on the proximal or on the distal of the long bone, namely, near to the joint, or in a case of an a segmental fracture that the fracture occurs over two regions thereof, or in case that a butterfly fragment is contained, a use of the fixator is impossible or the fixator has a problem that an efficiency in its fixing force drops. As its example there can be presented an orthofix. It is also impossible to add the ring and to change its shape according to some necessity since there is not a ring portion, even though its fixation operation is executed on several regions under the fracture state occurring over two regions. As its example it can be presented an AO monofixator. Further, in a neglected fracture or in a fracture having a severe bone shortening, the lengthening or distraction of the bone or an angulation correction force falls in its efficiency, and there occurs a cantilever effect caused by the unilateral distraction and the pressure in a case of the distraction and the compression.

In the basic concept of the circular fixatior, there are constructed a circular ring, a rod for fixing upper and lower rings, a K-wire piercing through both cortices of the bone so as to compress and fix the bone, and a clamp for fixing the K-wire to the ring. Under such construction, the fracture region is fixed, or the bone can be distracted or compressed. This ring fixator is formed by combining the circular ring with the rod having a thread provided through an overall outer circumference face thereof and by fixing both ends of the K-wire into the circular ring. With such construction, an interval between the upper and lower circular rings is modified by fastening or unfastening the bolt, to thereby enable the bone to be lengthened or compressed. Also, the angulation correction of the bone is available by installing a hinge of a constant shape between the upper and lower rings. But a severe pain is accompanied by the K-wire completely piercing through the bone and the muscles, and a limitation of the joint motion is caused, and furthermore, a danger possibility upon the blood vessel and the nerve injury is high. A user feels severe inconvenience in his movement since this fixator is used as a circular shape, and excepting of a specific purpose such as a bone lengthening etc., there are many improper elements in an application as a external fixator for a simple fracture, and too expensive cost of the product is also caused as the problem.

A development for a fracture external fixator based on a new method has been required in order to improve the problems of such existing ring fixator and unilateral pin fixator, and in order to attain such purpose, the fracture external fixator having the structure that the unilateral fixation and the ring fixation can be executed together has been ever presented under the Utility Application No. 96-20932 in Republic of Korea.

Such external fixator device is constructed by a long and short rod set having threads on its both ends or on its overall face, a ring set of an arch shape having different central angles, and a nut for combining the ring and the rod. With this construction, the rod and the ring are combined in various types, and after that, the pin or the K-wire is fixed to a hole formed on the ring and to the rod, so as to simultaneously g.et an effect of the ring fixation and the unilateral fixation, or enable to convert the unilateral fixation into the ring fixation and the ring fixation into the unilateral fixation according to a necessity. In addition, construction elements can be removed according to a recovery state of the fracture.

Despite of the above-mentioned many merits, the presented external fixator depends upon only the bolts in a combination of the ring and the rod, and thus bring about a complication in fastening and unfastening procedures of the component elements. In the midst of using the fixator, when it should be changed from the ring fixation state using two 1/2 rings to the unilateral fixation using the 1/3 rings, all the 1/2 rings should be removed and then the 1/3 rings must be combined there with because there are also provided, in the ring construction, 1/2 rings with the center angle of 180 degrees, 1/3 rings with the center angle of 90- 120 degrees and 1/10 rings.

Accordingly, much inconvenience is followed. If only one 1/2 ring out of two 1/2 rings is removed in a state that another 1/2 ring is used in the unilateral fixation as it is, in order to lessen such inconvenience in changing the ring fixation state to the unilateral fixation state, it is not externally neat since its length is too long in comparison with the length required for the unilateral fixation, which can also cause some inconvenience for a patient's action.

Disclosure of Invention

Accordingly, the present invention is directed to an optimum fracture external fixator on the basis of the presented external fixator capable of simultaneously performing the conventional unilateral fixation and ring fixation through a settlement of the following technical subjects.

It is, therefore, a primary object of the invention to provide a fracture external fixator, in which, not only a unilateral fixation and a ring fixation can be independently executed, but also a rod can be additionally set or can be removed according to a necessity under a state that a pin stuck into a fracture region is maintained, without causing some problems on a stability of the fracture^', and a change from the unilateral fixation to the ring fixation, or from the ring fixation to the unilateral fixation, can be freely attained, and the ring fixation and the unilateral fixation can be simultaneously performed so as to cope with the complicated fracture.

Another object of the invention is to provide a fracture external fixator capable of fixing the bone on an optimum position and direction. resulting in obtaining an optimum combination between component elements including a rod-to-ring clamp for joining a rod with a ring, a ring-to-ring clamp for connecting the ring and the ring, and a rod-to-rod clamp for combining the rod with the rod according to a type of the fracture, a free change of the fixation method, and an effective operation thereby.

A still another object of the invention is to provide a fracture external fixator capable of carrying out an optimum operation necessary for patients by using instruments based on the minimum number, minimizing a restriction for an action of the patient followed in an instrumental use, and thereby maximizing a satisfaction extent of the operated person by maintaining a neat external shape.

In accordance with the present invention for achieving the above objects, a fracture external fixator consists of a rod, a ring of an arch shape having numerous holes piercing through its upper and lower surface, a rod-to-ring clamp for joining the rod with the ring, a ring-to-ring clamp for combining and fixing the ring and ring, a pin for fixing a fracture region, being stuck in the bone, a pin-to-rod clamp for joining and fixing the pin to the rod, a pin-to-ring clamp for fastening the pin into the hole of the ring, and a rod-to-rod clamp for connecting the rod to the rod.

Brief Description of Drawings

The above and other objects and features of the instant invention will become apparent from the following description of preferred embodiments taken in conjunction with the accompanying drawings, in which:

Fig. 1 shows a construction view representing a basic combination in a fracture external fixator in accordance with the present invention;

Fig. 2 indicates a constructive view of a rod; Fig. 3 sets forth a constructive view of a ring;

Figs. 4a through 5b illustrate embodiment views of a rod-to-ring clamp and its use state views;

Figs. 6a and 6b furnish embodiment views of a ring-to-ring clamp;

Figs. 7a and 7b represent embodiment views of a pin-to-rod clamp and its use state views;

Figs. 8a and 8b depict embodiment views of a pin-to-ring clamp and its use state views;

Fig. 9 is an embodiment view of a rod-to-rod clamp;

Figs. 10 through 13c illustrate state views of an operation applied in the present invention; and

Figs. 14a and 14b indicate operation views for a segmental fracture state in a conventional unilateral pin fixator under.

Best Mode for Carrying Out the Invention

The preferred embodiments of the present invention are described in detail as follows, referring to the accompanying drawings.

An inventive fracture external fixator is constructed by a rod (1), a ring (2) of an arch shape, a rod-to-ring clamp (3) for joining the rod with the ring, a pin (5) for fixing fracture region, being stuck in the bone, a pin-to-rod clamp (6) for joining and fixing the pin to the rod, a pin-to-ring clamp (7) for combining and fixing the pin into the hole of the ring, and herewith, there are additionally constructed a ring-to-ring clamp (4) for combining and fixing the ring and ring and a rod-to-rod clamp (8) for connecting the rod to the rod.

Fig. 1 represents a basic combination embodiment based on the above construction, and such combination may be provided in various types according to the number of the component rods and a shape of ring. The rod 1 fixes the ring (2) or the pin-to-rod clamp (6), and in the rod (1⁾ there are threaded rods (la) having threads over its overall length and smooth rod (lb) as shown in fig. 2. These respective rods are classified into long, medium and short threaded rods and also long, medium and short smooth rods, which are respectively formed in different lengths.

A diameter of each rod is decided within a range enough to maintain the least friction force for preventing a rotational deformity in a combination with the clamp. Namely, the rod ( 1) can be prevented from itself excessive weight by determining the diameter thereof as around 8mm, and simultaneously, it can be ensured the adhesive force necessary for a fixation of the clamp. A length of the rod 1 is formed in a scope of 500- 100mm according to its long and short length under a consideration of the maximum length required in fixing the bone of a leg.

The ring (2) of the arch shape is decided by considering the maximum diameter of the operation region, since it is operated in such a type that the ring (2) externally surrounds around the calf or the thigh, that is, the ring (2) is constructed by a half-diameter of around 120-200mm. a width of around 15mm and a thickness of about 3mm.

There are also provided in such construction the rings (2) in series, wherein each of the rings has holes (2a) which are formed, piercing through its upper and lower sides with a constant interval, and the respective rings have mutually different center angles.

The center angle of the ring (2) is formed in a range enough to maintain an optimum fixation state of the fracture and to minimize an activity restriction of a patient. As shown in Fig. 3, it is desirable to employ, e.g., a 2/3 ring (2') having the center angle of around 225-240 degrees, a 1/3 ring (2") having the center angle of around 120- 135 degrees, and a 1/10 ring (2"') having the center angle of around 12-40 degrees, since they have a high rate in the practical use in performing an actual operation.

In the inventive ring 2 of the arch shape, it can be achieved a fixation effect same as the circular ring used in the conventional ring fixation, and at the same time, the burdensome feeling of the patient can be largely mitigated and his action can become free.

That is, it is operated in such a way that an opening part of the 2/3 ring (2') with the center angle of 225-240 degrees is directed to the backside of the knee joint, to whereby attain a sufficient fixation effect like a result a K-wire is used, even in operating on a region near to the joint by a fracture occurring on the proximal and the distal of the long bone, and also not to cause any inconvenience in a flexion of the patient's knee joint.

If necessary, the ring (2) of the arch shape can be used as the circular ring by joining and fixing the 1/3 rings through a use of specific rin-to-ring clamps, and also, according to a necessity, the 1/3 ring can be separated therefrom and a fixation effect can be obtained only by the 1/3 ring.

Each of the holes formed on each ring has a diameter of around 8mm in such a way that the rod can freely pass through the hole. A central distance between the hole and the hole is provided in about 15mm so as to ensure an installment space of the clamp used for a fixation of the pin.

In joining through the clamp, a chamber (2b) may be provided on upper and lower sides of the hole so as to maintain a contact pressure between the surface of the arch ring and the pin. Therefore, a pin hole of the pin clamp may be formed on a position a little lower than a taper part inserted into the hole, to thus ensure a fixation force based on a contact among the pin, the clamp and the ring in tightening up the clamp, and to accordingly enable to use the pin-to-ring clamps of various types.

In joining the rod 1 with the ring 2, it is performed by using a rod fixation nut (9) in a case of the threaded rod ( la) and using the rod-to-ring clamp (3) in a case of the smooth rod (lb).

The rod-to-ring clamp (3) is provided so as to realize a technical spirit for fixing the rod and the ring through various shapes and structures.

As shown in Figs. 4a and 4b showing one embodiment of the rod-to-ring clamp, there are constructed a rod insertion hole (3b) formed piercing through upper and lower sides of a cylindric body (3a), a ring insertion flute (3c) formed with a given depth from one end thereof, and a bolt hole (3d) formed from another end thereof, piercing through the ring insertion flute, so as to be fastened by a tightening bolt (3e).

As shown in Fig. 5, under a state that the hole (2a) formed on the ring coincides with the rod insertion hole (3b) formed on the clamp after inserting the ring (2) into the ring insertion flute (3c), the rod 1 is inserted and the tightening bolt (3e) is tightened up. Then, an end part of the tightening bolt pressurizes and fastens an outer side of the ring so that the rod and the ring may be joined.

Accordingly, the rod-to-ring clamp (3) with such construction provides an effect from very simple combination between the smooth rod and the ring.

The rod-to-ring clamp (3) may be also formed as shown in Fig. 5a by such a construction that an opening part (30 connected to the rod insertion hole (3b) thereof is provided on one side face of the body (3a).

In the rod-to-ring clamp based on such construction, as shown in Fig. 5b, the rod ( 1) is first inserted into a corresponding hole (2a) of the ring in order to join the ring and the rod, and then, the rod and the ring are inserted through the opening part, to thereby settle an inconvenience caused by joining the rod after a coincidence of the hole of the ring and the rod insertion hole of the clamp, namely to perform very simple combination between the ring and the rod.

The ring-to-ring clamp (4) is provided to obtain a circular arc shape of the ring necessary for an operation by joining the ring (2) and the ring (2) and may be provided in various structure for executing the combination of the ring an the ring.

Figs. 6a and 6b set forth one embodiment through a use of the ring-to-ring clamp (4). A body (4a) of the ring-to-ring clamp (4) shown in Fig. 6a is formed as a sectional shape of a V type, which is provided with a ring insertion flute (4b) formed on one side part thereof; and two bolt insertion holes (4c) formed piercing through upper and lower parts of the body and coinciding with the holes of the ring. Under this construction, both ends of a ring (2) to be joined with are inserted into the ring insertion flute, and bolts (4d) are fastened into the bolt insertion holes (4c).

The ring-to-ring clamp (4) shown in Fig. 6b has also the structure that a jaw (40 is formed on an outer side face of the body (4e) having the circular arc shape and two bolt insertion holes (4c) are formed piercing through the upper and lower faces of the body and coinciding with the holes of the ring.

The ring-to-ring clamp (4) combines the 2/3 ring with the 1/3 ring to produce a circular ring, and after a ring fixation by the circular ring, a fracture fixation method can be changed by partially separating some part of the ring according to a necessity.

The pin-to-rod clamp (6) is provided to maintain a fixation state between the rod and the pin, and can be used in assembling the body of the clamp with the rod and fixing the pin to the body of the clamp. Its detailed structure may be constructed in various types. Fig. 7a illustrates one embodiment of the pin-to-rod clamp (6). The pin-to-rod clamp (6) includes a body (6a) having a head part (6b) and a bolt part (6c) whose connection part is formed by a taper (6d) provided in a constant slant type, and also having a rod insertion hole (6e) piercing through upper and lower sides of the head part in a shape that a partial portion of the taper can be contained in its formation of the rod insertion hole (6e); and tightening metal (60, (6f) provided symmetrically on the right and left having a bolt insertion hole (6g) formed on its center, a taper formed on one tightening metal, for accommodating the taper, and a pin insertion hole (6h) formed on upper and lower sides of an adhesive part of the tightening metal (60, (6D; and a tightening nut (6i) assembled with the bolt part (6c) which passes through the center of the tightening metal and is projected to one side end of the tightening metal.

As shown in Fig. 7b, in the pin-to-rod clamp, the rod (1) is inserted into the rod insertion hole in a state that the right and left tightening metal is a little opened by loosing the tightening nut, and a top of the rod is determined by considering a direction and a position of the pin (5) stuck into the bone, and then the nut is tightened in a state that the body of the pin is inserted into the pin insertion hole (6h) to thereby fix the rod by a friction force between the surface of the tightening metal of one side and the rod insertion hole and fasten the pin by the contact pressure from the both tightening metal.

The pin-to-rod clamp rotates 360 degrees centering on the rod to thereby select its position and direction, and the tightening metal rotates 360 degrees against the clamp body to easily select an optimum fixation location based on the type of the fracture.

The pin-to-ring clamp (7) is constructed by a unit for joining and fixing the clamp body to the ring and a unit for fastening the pin to the clamp body. With such construction, the pin is fixed by using the holes formed on the ring. And the pin-to-ring clamp (7) may be provided in various structures or used as it is.

Fig. 8a furnishes one embodiment of the pin-to-ring clamp (7), and there are included a thread part (7c) formed from an end part of a taper ⁽7b) in a given length, a body (7a) having a pin insertion hole (7d) piercing through upper and lower sides thereof, and a tightening nut (7e) assembled with the thread part of the body.

The pin-to-ring clamp (7) with such construction is available to be rotated by 360° centering on the hole of the ring, and as shown in Fig. 8b, the pin is inserted into the pin insertion hole in a state that the thread part pierces through and is inserted into the hole of the ring, and the nut is tightened, then the fixation of the pin is completed.

The taper (7b) end of the pin-to-ring clamp is inserted into the chamber (2b) formed in the hole of the ring, then a lower part of the pin insertion hole is provided under the surface of the ring, accordingly the fixation of the pin is attained by a friction contact between the pin and the ring surface in tightening up the nut.

In a method for connecting the rod and the rod, two rod-to-ring clamps above-mentioned and the 1/3 ring can be used, but as shown in Fig. 9, two rod-to-rod clamps (8) and one rod can be also used, two rod-to-rod clamps (8) being provided equally to the same construction as the pin-to-rod clamp, and at the same time, being provided with the construction that a rod insertion hole having the same diameter as an outer diameter of the rod is formed on a position where the pin hole was located.

In such above case, the rod-to-rod clamp is joined on two rod standing perpendicularly, and a specific rod is combined horizontally with the clamp, therefore, the rod and the rod can be connected with each other and the pin can be fixed to the horizontal rod also by using the pin-to-rod clamp. The fracture external fixator with the above construction is described in detail as follows, referring to the accompanied drawings. Fig. 10 depicts an external fixation method in a case of a segmental fracture ( 11⁾ occurring on upper and lower parts of the long bone (10). In this fixation method, 1/3 rings (2") are disposed on upper, middle and lower parts on the front of the fixatior, and each smooth rod (lb) is joined with end parts of the rings, and in such state, two pins (5) fastened on the upper ring are fixed to a proximal segment (12). Then, one pin fixed to the middle ring and another pin fixed to the rod make a middle segment to be fixed. Also, one pin fixed to the lower ring and another pin fixed to the rod make a lower segment to be fixed.

In the above-mentioned method, accordingly, the pin can be fixed on a position where an operator wants, by the number of the pins the operator desires, through the hole formed on the ring and the pin-to-rod clamp installed on the rod. According to some necessity, 2/3 ring may be connected therewith on the backside by using the ring-to-ring clamp, to thus convert the first shape into a ring shape so that the fixation using the K-wire(including olive K-wire) is gained. Thereby, the compression and the distraction can be performed.

It is an established theory that a union of the fracture is promoted if the compression force operates upon the fracture region.

After the bone unite in some extent through the compression, the 2/3 ring positioned on the backside is removed to then reduce an inconvenience of the patient and make the patient's walk easy.

In such case, in selecting the conventional orthofix as shown in Fig. 14a, the fixation of the bone is not attained on three regions, namely the upper, middle and lower regions, thus instability or deformity of fracture can be occurred. In selecting the unilateral pin fixator as shown in Fig. 14b, the fixation only through the rod is gained, but the fixation through the ring is not gained, even though the fixation on three regions is achieved. That is, the compressing force is not provided on the overall bone but unilaterally operates towards a direction the half-pin is stuck, and not only the compression can not be well performed, but also the K-wire is not mixed in its use and a change into the ring type is impossible. In comparison with the conventional fixator, the inventive external fixator can settle these problems.

Fig. 1 1 offers a fixation method in a case of a fracture occurrence on the upper portion of the long bone. Referring to Fig. 11, the 1/3 rings (2") are disposed so as to be positioned on upper and lower parts of the fracture, a smooth rod (lb) of a long length is joined in a center part of the ring, and threaded rods ( la) of a short length is assembled at both ends of the ring. Under such state, the proximal segment of the bone is fixed by two pins fastened to the upper ring, and the lower segment is fixed by two pins fastened to the lower ring and is also fixed by two pins fastened on the smooth rod exposed in the lower direction.

The performance of the compression and the distraction is also available in the above fixation method.

In other words, the compression can be done by tightening up the rod fixation nut (9) of the right and left threaded rods in a state that the bolt of the rod-to-ring clamp (3) is a little unfastened, and the distraction can be attained by unfastening the nut (9).

Fig. 12a gives a fixation method in a case that a line of the fracture is very approximate to the joint. The 1/3 ring (2") and the 2/3 ring (2') are combined by the ring-to-ring clamp (4), to then produce two circular rings. Two circular rings are disposed on the upper and lower positions, and the rods are inserted into four components to join the ring and the rod. Under such state, the proximal segment is fixed by the K-wire (14) and two pins by using the upper ring, and the distal segment is fixed by the K-wire and three pins fastened on the lower ring and the central rod.

Two out of 4 rods used in such case can be changed to threaded rods, and the distraction and the compression upon the fracture region can be gained by adding another threaded rod.

Fig. 12b shows a state that the 2/3 ring and the K-wire positioned on the backside are removed according to the status of the bone union, after the fixation execution in Fig. 12a, and a change into the a unilateral fixation state is provided. This change can be easily gotten by unfastening the ring-to-ring clamp and can provide the patient with a remarkably free action comparatively with the ring fixation state.

Fig. 13a presents a fixation for the fracture occurring on a middle portion of the long bone by using the smooth rods of long and short length and the ring segment connecting the rod with the rod. In this case, as shown in Fig. 13b, the fixation can be obtained by connecting the rod and the rod through a use of the rod-to-rod clamp (8).

In such method, a restriction to the patient's action may be lessened with instruments of the minimum number in the unilateral fixation, and a stability on the fracture region can be maximized in the unilateral fixation.

Fig. 13c indicates a change of fixation from unilateral 2-plane fixator to unilateral 1 -plane fixator in which one rod and four pins are used, when it needs to perform other operation such as a skin graft after a union of the bone is progressed by some extent from the state in Fig. 13b or in the midst of the treatment, and such method can be applied even to a simple fracture with good stability.

On the contrary, firstly, other operation such as the skin graft etc. is finished in the simple fixation state shown in Fig. 13c. and after that, an additional pin can be used for the fixation by using the rod-to-rod clamp as shown in Fig. 13b, or the additional pin can be used by installing the ring. In non-described numbers in the drawing, 15 represents a clamp for fixing a half-pin. 16 provides a thread, and 17 indicates a rod-to-rod clamp used in former unilateral fixator.

In using the inventive system additionally to the fixation methods described on the above, more various and optimum combination state based on a fracture type may be provided. In accordance with the present invention, further, it can be available to change to an effective fixation method for minimizing the patient's inconvenience according to the patient's fracture state or the fracture union state, in other words, it is available to change from more complicated unilateral multiplane fixation to the unilateral 1 -plane fixation, or from the ring fixation to the unilateral fixation. Like this, various operating methods having a difficulty caused in the conventional unilateral or ring fixation systems can be used in the present invention.

As afore-mentioned, the inventive fracture external fixator includes the rod, the ring, the rod-to-ring clamp for joining the rod with the ring, the half-pin for fixing a fracture region, being stuck in the bone, the pin-to-rod clamp for joining and fixing the half-pin to the rod, the pin-to-ring clamp for combining and fixing the half-pin into the hole of the ring, the ring-to-ring clamp for combining and fixing the ring and ring and the rod-to-rod clamp for connecting the rod to the rod. In such inventive construction, an effective and appropriate operating method can be freely performed in various types of the fracture, and an inventive basic spirit can be realized, namely a change from the unilateral fixation to the ring fixation, or from the ring fixation to the unilateral fixation, according to the necessity. In addition, the above-mentioned operation method or the detailed embodiments of component elements are not to limit the basic spirit of the present invention, but the concrete shape and structure of the clamp can be changed to various types based on the optimum operation method and O 99/48414

some necessary functions.

In accordance with the present invention, as the above-mentioned, not only a unilateral fixation or a ring fixation is independently used by joining a rod and a ring, but also it is freely executed to change from a unilateral fixation to a ring fixation, or from the ring fixation to the unilateral fixation, according to the necessity, under a state that a half-pin stuck into the fracture region is maintained, to accordingly gain an effect of the optimum fracture treatment by partially unfastening the instrument or by a change of the fixation method, correspondingly to a union state of the fracture. That is, the optimum fixation method .can be herein achieved through a use of the minimum instruments to whereby minimize an inconvenience of the patients. Furthermore, a proper fixation method based on an operator's intention can be selected to thus curtail the labor for operation, remarkably reduce a pain or an activity restriction caused by putting on the fixator, and also provide a neat external shape.

Although the invention has been shown and described with respect to the preferred embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims

Claims^

1. A fracture external fixator comprising: a rod; a ring of an arc shape; a rod-to-ring clamp for joining the rod with the ring; a half-pin stuck in the bone, for fixing a fracture region; a pin-to-rod clamp for assembling and fixing the said half-pin to the rod; and a pin-to-ring clamp for combining and fixing the half-pin into a hole of the ring, thereby enabling to comp╬▒sitely perform a unilateral fixation and a ring fixation by mutually assembling respective component elements and mutually change a unilateral fixation method and a ring fixation method according to a union progress state of the fracture.

2. The fixatior of claim 1, wherein the said rod comprises: a threaded rod having a formation of a thread on an overall length there of; and a smooth rod, the said rods being respectively provided as long, middle and short threaded rods and as long, middle and short smooth rods.

3. The fixator of claim 1, wherein the said ring of arc shape comprises a 2/3 ring having a center angle of around 225-240┬░, a 1/3 ring having the center angle of around 120-135┬░, and a 1/10 ring having the center angle of around 12-40┬░, the said ring of the arc shape being constructed by serial rings formed by different center angles from one another, and the said rings being provided with the holes piercing through upper and lower sides thereof with a constant interval.

4. The fixator of claim 1, 2 or 3, further comprising: a ring-to-ring clamp for combining and fixing the ring and the ring; and a rod-to-rod clamp for connecting the rod to the rod.