CA1331549C - External dynamic bone fixation device - Google Patents
External dynamic bone fixation deviceInfo
- Publication number
- CA1331549C CA1331549C CA000509457A CA509457A CA1331549C CA 1331549 C CA1331549 C CA 1331549C CA 000509457 A CA000509457 A CA 000509457A CA 509457 A CA509457 A CA 509457A CA 1331549 C CA1331549 C CA 1331549C
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- Canada
- Prior art keywords
- curved surface
- block
- bone
- fixation
- joint
- Prior art date
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Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/56—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
- A61B17/58—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
- A61B17/60—Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like for external osteosynthesis, e.g. distractors, contractors
- A61B17/64—Devices extending alongside the bones to be positioned
- A61B17/6425—Devices extending alongside the bones to be positioned specially adapted to be fitted across a bone joint
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- Health & Medical Sciences (AREA)
- Orthopedic Medicine & Surgery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Surgery (AREA)
- Biomedical Technology (AREA)
- Engineering & Computer Science (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Heart & Thoracic Surgery (AREA)
- Medical Informatics (AREA)
- Molecular Biology (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Surgical Instruments (AREA)
Abstract
EXTERNAL DYNAMIC BONE FIXATION DEVICE
Abstract An external fixation device for the fixation of a broken joint includes first and second fixation rods connected to bone pins intended to be introduced into the bone, and an articulating portion joining the two rods. One of the two fixation rods is connected to a sliding block that slides within the housing of the articulating portion upon a sliding surface having a virtual axis. The articulating portion housing is provided with viewing lines on its cover for accurately sighting the location of the articulation axis of the prosthetic joint.
Abstract An external fixation device for the fixation of a broken joint includes first and second fixation rods connected to bone pins intended to be introduced into the bone, and an articulating portion joining the two rods. One of the two fixation rods is connected to a sliding block that slides within the housing of the articulating portion upon a sliding surface having a virtual axis. The articulating portion housing is provided with viewing lines on its cover for accurately sighting the location of the articulation axis of the prosthetic joint.
Description
P.C. ` 70 74 EXTERNAL DYNAMIC BONE FIXATION DEVIC~
Background of the In~ention The present invention relates to medical equipmenJ
and more particularly to an apparatus for bone fixation allowing the movement of bones at a broken joint.
For the purposes of this invention, such a fixation is termed a t'dynamic fixation". This designates a bone fixation, by means of pins, bars and external supports, which has an articulation in gecmetrical relationship with an articulation of ~he human or animal body, allowin~ the fixation of bone fragments of each one of the bones which are articulated, but allowing also a pivoting movemen~ Oc the parts of.the fixation device about their axis of articulation.
. External anchoring or fixin~ of bones is an old sur~ical technique which was first used a century a~oO ~ ~.
Its application has for a long time been limited ~o complicated fractures in traumatology and conse~u2ntly in orthopedics, i.e the secondary treatment of . fractures, infections, slow knitting of the bones, pseudarthroses, difficult bone-settings, etc. Extern~l anchoring is used particularly for lons bones such as the femur, the tibia, the humerus, the radius and the --. 25 cubitus. However, it is also desirable to manu~actu~e -~- small anchoring means which can be used on small bones, such as the metatarsals and the metacarpals, and in .:
^- max.illofacial surgery as well as in experimental surgery on small animals.
External bone-anchoring elemen~s enable two kinds of bone-anchoring to be carried out:
- transfixing anchoring, wherein the pins extend from one side of the limb to the other, and ~?.` ', '~ -2 ~ 33~54q non-transfixing anchoring, wherei~ the pins are introcluced into the bone without completely transversing it.
Transfixing anchorage, which is mostly used on the leg, is more rigid than non-trans~ixing anchorage. At ~ -both sides of the bone are fitted two rods or frames~
upon which are anchored two groups of pins disposed on either side of the fracture. The two frames or the two rods are interconnected by a brace which is as stable lQ as possible and which may comprise sliding rods or bars, the length of which can be increased or reduced.
Thus the basic techniques of ~xternal b~ne fixation are already known. Consideration has already been given to extending external bone fixation to the -osteosynthesis of broken joints. This idea was to fix the bone fragments of the broken joint parts to the adjacent bones by means of thin pins, to introduce fixation pins into the other member of the joint (which may also be broken or not~ also, and to join these two parts of the external fixation device by an articula~
tion coupling. The purpose of this articulated fixa-tion is the rollowin~. Normallv, a rigid bone ixation would be a sufficient means for curing the broken bone.
However, when ~his broken bone is part of a joint, there is a great risk that the joint will remain stiff after healing, and it is considered dS absolutely ;
~'- necessary that the patient make movement exercises with - -his broken joint as soon as possible. Such movements . .
- should begin with a small angle of flexion which will gradually be increased. All these movements must of co~lrse be permitted by the mounted extexnal fixation device., and that is not the case with the rigid fixa-tion device described, for example, in U.S. Patent No.
4,365,624.
i:.
sl:
A dynamic external fixation device has been described in the French Patent Application No. 2,551,650 published March 15, 1985, of Terry A. Clyburn. This fixation devlce comprises, following the general idea mentioned above, a first proximal branch and a second distal branch, these branches being adapted for fixably receiving fixation pins, and a univeræal joint, typically a ball joint, linking said two branches.
In order to function correctly, the fixation device must of course be applied strictly in such a manner that the point of articulation between said branches of the device will lie exactly on the pivot axis of the wrist joint; otherwise, undue and painful tensions or compressions occur when the hand is to be moved with respect to the arm. However, this axis of articulation in the joints is in most cases not detectable with sufficient precision when there is a fresh fracture, all of the area being ~wollen and the joint not being pivotable. Furthermore, the location of the articulation point of this known device cannot be adjusted.
SummarY of the Invention It is a first and primary object of this invention to provide a new and useful dynamic external bone fixation device for the healing of bone fractures in the joint area which does not suffer from the disadvantages llsted above.
The invention provides a dynamic external bone fixation :~
device for the osteosynthesis of a broken joint, compriæing~
a first part comprising a first fixation rod having an axis a1 for connection to bone pins introduced into the bone on one side of said joint, (2) a second part comprising a second fixatlon rod having an axis a2 for connection to bone pins introduced into the ~'' .
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133154q :
bone on the other side of said joint, and (3) an articula~ing portion joining said first part and said second part, said articulating portlon comprising: ~a) a first curved surface to which said first part is connected and which flts with a second curved surface to which said second part i5 connected so as to allow adjustably limited movement of said first part with respect to said second part, both said first curved surface and said second curved surface having a common virtual axis spaced apart from said device, and (b) means for locating said common virtual axis so that said virtual axis may be aligned with the axis of said jolnt, wherein said means for locating said virtual axis i~
an integral element of said device.
The device allow~ exercise of the injured joint, under gradually increasing angles and with controllable moving resistance. The fixation device can be positioned by the surgeon in a very exact manner with respect to the pivot axis of the in~ured joint, and can be ad~usted, as to the extent of articulation, even after the setting of the flxation pins. The disclosed dynamic external bone fixation device for application to broken joints further permits a compression or extension treatment ln the course of the healing period of the bones so that there i~
a perfect reconstitution of the joint and of its mobility.
In order to make the terms and notions of the art more easily understood, reference is made to U.S. Patent No. 4,365,624.
It has surprisingly been found that the device of the invention can not only be used with wrist fractures but also with fractures of other ~oints such as the knee, ankle, finger, elbow, shoulder and even the pelvis and collarbone.
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4a 64680-384 The dynamic external bone fixation device ~f this invention has been developed from the basic idea that the device ~:
should not be placed laterally to the .
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~ 1 33 1 549 ~
fractured ~olnt of the body, in such a way that the center of artlculatlon of the two fixation parts lies also ln the plvot axls of said ~oint, but generally vertlcally to the jolnt, namely ln a plane higher than the plane of the body. This wlll be exp~ained below and lllustrated ln the flgures.
Thls dlsplacement of the polnt of articulatlon of the instant fixation device results ln another geometrlcal implemen-tation; the slmple plvoting movement of a universal or ball ~olnt, as known before, ls to be replaced by a simultaneous pivoting and extenslon (or contractlon) movement. Thus, the lnventlon pro-vldes, besldes two flxatlon parts to be flxed ln the bones on both sldes of the fractured ~olnt, an artlculatlng portion comprlslng curved, preferably cylindrlcally curved, slldlng surfaces; one of these surfaces ls convex and is a part of a ~'posltlve" element connected to one of sald flxatlon parts, and the other one ls concave and ls a part of a "negatlve" element connected to the other flxatlon part. When these surfaces sllde one over the other, one skllled ln the art easlly understands that the elements fixed to either surface wlll make a combined angular and longltu-dinal movement.
The concave surface is a part of a slldlng block whlchls able to sllde on a correspondlng convex surface ln the interlor of a houslng. This housing has a lateral closure, belng at a right angle to the axis of said curved surfaces. The closure and, preferably, the other lateral surface of the housing are provlded with a plurallty of stralght llnes having one point of lnter-sectlon outslde of the housing. Thls polnt of lntersectlon (and therefore the dlrectlon of sald llnes) ls selected so as to deflne the axls of the curvature of sald slldlng surfaces. Thls axls ls also the plvoting axls of the bone ~olnt. When the surgeon ~ -6- 1331549 applies the fixation device of the invention to the body, he will be able to aim at the joint axi~ in looking along said lines. He will very easily find said axis, even if the joint re~ion is swollen, and he has the possibility of readjusting, if possi~le, the fixaition device of this invention, as will be explained later.
The sliding block may be fixed by a screw which traverses a slot in the housing. This slot is curved and follows the curvature o' the sliding surfaces.
~nother screw, to be locked in said slot only, ser~Jes as a stop for limiting the movement of the sliding block in the housing. In the neighborhood of the slot, angle indications may be provided. The sliding sur-1 ~ faces m~y be c ~ er~ed by an antifrictional layer, forexample of te~e~ (PT~E) or nylon.
The materials of the instant fixation device will be selected to withstand repeated sterilization. This selection of materials is conventional for the man skilled in the art.
Furthermore, it is preferred to control the movement of the sliding block in the housing with regard to the force necessary for displacing the sliding block, in order to be able to establish a ; 25 suitable training or recovery program for the patient.
In one group of embodiments, the sliding block movement ~ is impeded by spring forces, be it a torsion spring or the elastic force of a rubber strip; in another embodi-ment, a frictional force is applied to said movement.
The amount of said frictional force may preferably be controlled between nearly zero to complete blocking.
Detailed Description of the Invention In order to explain the dynamic external bone fixation device of this invention in more detail, - : . ..
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... -.. .. ~ . .... . . . i l .. - .... ~ . . . ... . . . . ..
~ -7- 1 33 1 54q several preferred embodiments thereof will be described with xeference to the attached drawings wherein:
FIGU~E 1 is a lateral elevational ~iew of a dynamic connection member showing the neutral position of the connection bars in full lines and their maximally perrnitted position in dotted lines.
FIGURE 2 is a longitudinal sectional view of the connection member of FIGURE 1, in a first embodiment including a spring to resist the patient's movement. -FI~URES ~ and 4 are partial views similar to PIGURE 2, showing embodiments where biasing means are respectively an elastic member and a frictional bxaXe~
FIGURE 5 is a perspective view of a dynamic external wrist fixation device comprising two groups of two pins each, these groups being connected to two corresponding bars,these bars being linked to the dynamic connection member.
FIGURE 6 is a section view taken alon~ line VI-VI
in ~IGURE 5, in an embodiment in which the pins are angulated at 40.
FIGURE 7 is a partial view, taken in sectlon along line VII-VII in ~IGURE 1, showing the connection me~er in a locked position. -FIGURE 8 is an enlarged detail of FIGURE 4 which illustrates an embodiment using a frictional brake to resist the patient's movement.
The dynamic external bone fixation device represented ~ --in PIGURES 1 and 2 comprises an articulating portion 1 ioining the rods 2 and 3.
As explained below, the rod 2 is to be connected ; to the pins fixed in the patient's metacarpus by means of a coupling schematized in 4. Similarly, the rod 3 is to be linked to the patient's radius by means of the coupling schematized in 5.
` \ -8-The articulatiny portion 1 is principally consti-tuted of a housing 6 and of a sliding block 7 which are both capable o~ sliding with respect to a sliding ~.
surface 8.
In other terms, the housing 6 presents a c~nvex sliding surface 8 whereas the sliding block 7 presents a corresponding concave sliding sur~ace. These sliding surfaces are for example cylindrical surfaces, the axes ~-of the corresponding cylinders being normal to the~
sliding plane of the articulating portion 1. In the drawings, this virtual axis is represented by A and corresponds to the axes of movement of tile f.actured wrist.
The housing 6 is realiz.ed either iIl a li~ht a loy or a synthetic material capable of withstanding steri- ~ -lization, since ali components of the device must be gas or steam autocl~ved. Th~ sliding block 7`i.s made, for example, of stainless steel.
The sliding surfaces 8 of the housillg 6 and/or of ~ ~:
the slid-ng block 7 comprise a slippery covering, not shown in the drawings, for instan~e nylon or teflon ; (PTFE).
W:;th reference to FIGURE 1 or 2, one will note that the general ~orm of the housing 6 is slightly curved according to the sliding surface 8. The inferior part of housing 6 pre~ents a curved face 9.
.. A pin lO fixes the extremity of the rod 2 in.the :~
sliding block 7. The extremity of the other rod 3, which is unthreaded, is fitted in a threadad:rod 11 and .. :~
. 30 is held in place with two knurled wheels 12 and 13, - ~ ~
allowing the adjustment in length of the unit .,:.. r.. ~.
comprising the articulating portion 1 and the rods 2 and 3, whereas any lateral displacement is avoided by means of the extending element 14. The othex extremity of the threaded rod 11 cooperates with the housing 6, ~ .
, ~
1 33 1 54q elther by dlrect screwlng, or by means o~ a pin 15, as illustrated ln FIGURE 2.
Another component of the artlculatlng portion 1 ls a lateral cover 16 whose general shape follows that of the houslllg 6. -~
The vlslble face of that lateral cover 16 presents a :~ :
scale 17 for the reading of relative angular movements between the slldlng block 7 and the houslng 6 and lts lateral cover 16. Some of the graduatlons of the rounded scale 17 are enlarged and ex- :
tended to form vlewlng llnes 18, almlng at the vlrtual axls A.
One could also envlsage disposlng vlewlng llnes on the slde of the housing opposite to the cover 16 (not visible ln the drawings). -~
The scale 17 and its corresponding mentloned numbers on the one hand and the vlewlng llnes 18 on the other can either be painted or engraved ln the cover and the houslng.
As shown in the detalled cross section of FIGURE 7, the slde of the houslng 6 faclng the lateral cover 16 presents an ~ ~-openlng 19 correspondlng to the slldlng block 7. As can be seen .~ :
ln FIGURE 2, the openlng 19 ls rounded to permlt the relatlve movement between housing 6 and sllding block 7. Identlcally, the .~ ~ :
cover 16 presents a rounded slot 20, the center of whlch ls also ~ :
In FIGURE 1, the slot 20 ls represented wlth two screws 21 and 22. The flrst ls a locking screw 21, preventlng any rela~
tlve movement between housing 6 and sliding block 7 (see FIGURE : -:
7). The second ls a limltlng screw 22, whlch is ad~usted on the cover along the scale 17, to llmlt the slot 20 and consequently sald relative movement, when the screw 21 ls unlocked.
In the first embodiment represented in FIGURE 2, the relatlve movement of houslng 6 and sliding block 7 X ~ .
-lo- 1331549 I is biased by a spring 23, an extremity of which is ! fixed in ~he hvusing 6 by a pin 24 while th2 other ~ -coop2rates ~ith the sliding block 7. II1 that embodi-ment, the opening 19 includes an extension 25 in which the spring 23 is localized in the position represented in full lin~s.
Although not shown in the drawings, an~ other torsion spring lin shape or disposition) may be used to directly or indi~ectly cooperate with both housing 6 and sliding block 7.
The means of impeding t,he movement o f block 7 within the housing 6 may alternatively be a rubber strip or ribbon 26, extending through both housing 6 and sliding block 7. In th~ embodiment presented in FIGURE 3, one free end of the rubber strip 26 is held by a metallic ring 27 taking rest on a flat surface 28 provided on the sliding block 7. The other end of the rubber strip 26 is directly fixed to the housing 6 from the outside, by means of a conical screw 29 Any other fixation of a rub'~er strip can also be ' ;~
- considered without extending beyond the scope of the present invention.
FIGURE 4 represents an embodir,ler~t u~sin~ a fric- '' tional brake, the force of which can be controlled. -' This frictional brake is composed principally of~ r~
a fixed part 30~,scre~ed into the ; housing 6, - a stuffing box screw 31, adapted to be ._ . , screwed on that fixed part 30, and = . , .~
- 30 - a piston rod 32, sliding in the-stuffing box screw 31, an extremity of which extends through the ~I fixed part 30 and cooperates with the sliding block 7, by means of a pin 33 entering in a corresponding opening provided in slidin~ block 7.
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-~ .
As shown ln the detalled FIGURE 8, the flxed part 30 and the stufflng box screw 31 both present an extenslon, 34 and 35 respectlvely, lntended to cooperate with a serles of O-rlngs 36 and pressure rlngs 37 disposed around the plston rod 32. The sectlon of the pressure rlngs 37 presents an lnternal V-shape, the functlon of whlch wlll be explalned later on.
The plston rod 32 ls made of burnlshed stalnless steel or another well-pollshed materlal. The other components of thls embodlment are made of materlals capable of wlthstandlng sterlll-zatlon.
The flxed part 30 and the stufflng box screw 31 both present scales, 38 and 39 respectlvely, for readlng the amount of frlctlonal force. The lndlcatlons of scales 38 and 39 are elther -~
palnted or engraved. ;~
After the above descrlptlon of several embodlments of the present lnventlon, the posltlonlng of such a dynamlc external bone flxatlon devlce wlll now be explalned.
Wlth reference to FIGURE 5, the artlculatlng portlon ls schematlzed ln 1. Uslng the same reference numbers as ln the foregolng descrlptlon, the rods 2 and 3 are flxed ln the ball ~olnts 4 and 5, mounted on two clamps 40 and 41.
The base-plates 42 and 43 of the clamps 40 and 41 are covered by a flber-relnforced phenollc materlal to flrmly hold the serles of plns 44 and 45 dlsposed ln the metacarpus 46 and ln the radlus 47. One can remark that the base-plates 42 and 43 present holes fltted to exactly posltlon the plns 44 and 45.
Wlth reference to FIGURE 6, one can further remark that the flxatlon devlce ls very near to the ~~ -12- 1 33 1 549 fractured menlber, as the pins 44 are fixed in the second mGtacarpus 46 with an angulation up to 45, for clinical reasons which will be detailed later on.
With reference to FIGURE 5, the setting up of the device will be detailed.
According to well known techni~ues, at least two pins 44 are inserted in the second metacarpus 46. The pins 44 can be provided with continuous threads, having a self-drilling point at one end. The opposite end of the pins 44 is designed for secure insertion into a chuck, not represented in the drawings. The self-tapping thread provides maximum gripping power.
Alternatively, one can use non-self-drilling pins, which are inserted in pilot holes through both cortices. Of course, one can employ a guide to obtain the correct disposition of the pins 44. ~ ~
Both pins 44 in the metacarpus 46 are fixed in the ~ -ba~e~plate 42 of the clamp 40. .
After approximate alignment of the fracture, at least two pins 45 are similarly inserted in the radius -.~ . . .
i 47 and fixed in the base-plate 43 of the clamp ~1.
. . , Both clamps 40 and 41 are provided with ball joints 4 and 5 in which one can fix the extremities of the rods 2 and 3, by means of wing nuts 48 and 49.
When reducing the fracture, the practitioner disposes the device in the co~xect position ~y first centering the view lines 18 on the pivot axis of the joint and then fixing the device by means of the wing :~ nuts 48 and 49.
~ 30 An X-ray may then be taken to determine the .....
correct reduction of the fracture. If necessary, the wing nuts may be loosened and further manipulation may be carried out.
Further adjustment may be realized by means of the knurled wheels 12 and 13, which are first centered on :
. .
...... ., . ~... ~ ., " ,. ... ... . .
the threaded rod 11 and then dlsplaced to ensure the necessary extenslon. Durlng lnitlal heallng, the devlce ls blocked by means of locklng screw 21 (FIGURES l and 7).
As already mentloned ln the lntroductlon, lt ls deslr-able to glve progresslve motlon to the ~oint after an lnltial perlod when the devlce malntalns constant flxatlon of the frac- ~-tured member.
Wlthout glvlng a complete program, one can propose to control the amount of flexlon accordlng to the followlng table, ~:
1st week after fracture no movement 2nd " " " no movement 3rd " " " flexlon up to 10 4th " " " flexlon up to 20 5th " " " flexion up to 30 6th " " " flexlon up to 40 The amount of flexlon authorlzed wlll be determlned by the practltloner who wlll lock the llmltlng screw 22 ln the cor-responding posltlon. .
For lnstance ln FIGURE 1, the rotatlon ls llmlted by means of screw 22 to a rotatlon of 20, and consequently the rela-tlve movement of rods 2 and 3 takes place between the neutral posltlon represented ln full llnes and the maxlmum rotatlon posl-tlon, represented ln dotted llnes.
Referrlng to FIGURE 2, one can further note that ln the neutral posltlon, represented ln full llnes, the rods 2 and 3 are not allgned, but form an angle alpha of about 10. Thls ls due to the normal posltlon at rest of the wrlst. The angle of rotatlon beta represented ln thls flgure ls so comprlsed between 0 and 40.
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.. ~ ~ . ~: - . . ~ , ., ., :
As alreaay mentioned, it is significant that the mov~ment during healing can be realized again~t the influence of a force.
In the embodiment proposed in FIGURES 2 and 3, this force is generally not linear, as neither the ~--spring 23 nor the elastic member 26 creates ~ reaction of equivalent force according to its position.
To further improve the device, the embodiment of FIGURE 4 ldetailed FIGURE 8) is proposed. In this version the movement is equally biased in both directions as the reactional foxce is du~ to the friction of the rod 32 against the O-rings ~6.
Furthermore this force can be regulated, either by the patient or by 'che practitioner, by turnin~ the stuffing box screw 31. Thus when the extensions 34 and - 35 come closer together, the O-rings 36 are pressed against the piston rod 32 as they are pressed between the rings 37 whose sectional shape is a V pointin~
towards the centerO Contrarily, the force ls reduced when the extensions are separated, as consequently the pressure of the O-rings is reduced~
The graduations of the scales 38 and 39 enable thP
reading vf the value of the friction. The scales 38 and 39 can be so graduated as to form a vernier.
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Background of the In~ention The present invention relates to medical equipmenJ
and more particularly to an apparatus for bone fixation allowing the movement of bones at a broken joint.
For the purposes of this invention, such a fixation is termed a t'dynamic fixation". This designates a bone fixation, by means of pins, bars and external supports, which has an articulation in gecmetrical relationship with an articulation of ~he human or animal body, allowin~ the fixation of bone fragments of each one of the bones which are articulated, but allowing also a pivoting movemen~ Oc the parts of.the fixation device about their axis of articulation.
. External anchoring or fixin~ of bones is an old sur~ical technique which was first used a century a~oO ~ ~.
Its application has for a long time been limited ~o complicated fractures in traumatology and conse~u2ntly in orthopedics, i.e the secondary treatment of . fractures, infections, slow knitting of the bones, pseudarthroses, difficult bone-settings, etc. Extern~l anchoring is used particularly for lons bones such as the femur, the tibia, the humerus, the radius and the --. 25 cubitus. However, it is also desirable to manu~actu~e -~- small anchoring means which can be used on small bones, such as the metatarsals and the metacarpals, and in .:
^- max.illofacial surgery as well as in experimental surgery on small animals.
External bone-anchoring elemen~s enable two kinds of bone-anchoring to be carried out:
- transfixing anchoring, wherein the pins extend from one side of the limb to the other, and ~?.` ', '~ -2 ~ 33~54q non-transfixing anchoring, wherei~ the pins are introcluced into the bone without completely transversing it.
Transfixing anchorage, which is mostly used on the leg, is more rigid than non-trans~ixing anchorage. At ~ -both sides of the bone are fitted two rods or frames~
upon which are anchored two groups of pins disposed on either side of the fracture. The two frames or the two rods are interconnected by a brace which is as stable lQ as possible and which may comprise sliding rods or bars, the length of which can be increased or reduced.
Thus the basic techniques of ~xternal b~ne fixation are already known. Consideration has already been given to extending external bone fixation to the -osteosynthesis of broken joints. This idea was to fix the bone fragments of the broken joint parts to the adjacent bones by means of thin pins, to introduce fixation pins into the other member of the joint (which may also be broken or not~ also, and to join these two parts of the external fixation device by an articula~
tion coupling. The purpose of this articulated fixa-tion is the rollowin~. Normallv, a rigid bone ixation would be a sufficient means for curing the broken bone.
However, when ~his broken bone is part of a joint, there is a great risk that the joint will remain stiff after healing, and it is considered dS absolutely ;
~'- necessary that the patient make movement exercises with - -his broken joint as soon as possible. Such movements . .
- should begin with a small angle of flexion which will gradually be increased. All these movements must of co~lrse be permitted by the mounted extexnal fixation device., and that is not the case with the rigid fixa-tion device described, for example, in U.S. Patent No.
4,365,624.
i:.
sl:
A dynamic external fixation device has been described in the French Patent Application No. 2,551,650 published March 15, 1985, of Terry A. Clyburn. This fixation devlce comprises, following the general idea mentioned above, a first proximal branch and a second distal branch, these branches being adapted for fixably receiving fixation pins, and a univeræal joint, typically a ball joint, linking said two branches.
In order to function correctly, the fixation device must of course be applied strictly in such a manner that the point of articulation between said branches of the device will lie exactly on the pivot axis of the wrist joint; otherwise, undue and painful tensions or compressions occur when the hand is to be moved with respect to the arm. However, this axis of articulation in the joints is in most cases not detectable with sufficient precision when there is a fresh fracture, all of the area being ~wollen and the joint not being pivotable. Furthermore, the location of the articulation point of this known device cannot be adjusted.
SummarY of the Invention It is a first and primary object of this invention to provide a new and useful dynamic external bone fixation device for the healing of bone fractures in the joint area which does not suffer from the disadvantages llsted above.
The invention provides a dynamic external bone fixation :~
device for the osteosynthesis of a broken joint, compriæing~
a first part comprising a first fixation rod having an axis a1 for connection to bone pins introduced into the bone on one side of said joint, (2) a second part comprising a second fixatlon rod having an axis a2 for connection to bone pins introduced into the ~'' .
~
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s ., . ~ ;, . . ~ . . . . .
133154q :
bone on the other side of said joint, and (3) an articula~ing portion joining said first part and said second part, said articulating portlon comprising: ~a) a first curved surface to which said first part is connected and which flts with a second curved surface to which said second part i5 connected so as to allow adjustably limited movement of said first part with respect to said second part, both said first curved surface and said second curved surface having a common virtual axis spaced apart from said device, and (b) means for locating said common virtual axis so that said virtual axis may be aligned with the axis of said jolnt, wherein said means for locating said virtual axis i~
an integral element of said device.
The device allow~ exercise of the injured joint, under gradually increasing angles and with controllable moving resistance. The fixation device can be positioned by the surgeon in a very exact manner with respect to the pivot axis of the in~ured joint, and can be ad~usted, as to the extent of articulation, even after the setting of the flxation pins. The disclosed dynamic external bone fixation device for application to broken joints further permits a compression or extension treatment ln the course of the healing period of the bones so that there i~
a perfect reconstitution of the joint and of its mobility.
In order to make the terms and notions of the art more easily understood, reference is made to U.S. Patent No. 4,365,624.
It has surprisingly been found that the device of the invention can not only be used with wrist fractures but also with fractures of other ~oints such as the knee, ankle, finger, elbow, shoulder and even the pelvis and collarbone.
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1331549 : ~
4a 64680-384 The dynamic external bone fixation device ~f this invention has been developed from the basic idea that the device ~:
should not be placed laterally to the .
-.
~ ' : - ~
. , .. ... . .. . . , . . . , ~ , .. . . .
~ 1 33 1 549 ~
fractured ~olnt of the body, in such a way that the center of artlculatlon of the two fixation parts lies also ln the plvot axls of said ~oint, but generally vertlcally to the jolnt, namely ln a plane higher than the plane of the body. This wlll be exp~ained below and lllustrated ln the flgures.
Thls dlsplacement of the polnt of articulatlon of the instant fixation device results ln another geometrlcal implemen-tation; the slmple plvoting movement of a universal or ball ~olnt, as known before, ls to be replaced by a simultaneous pivoting and extenslon (or contractlon) movement. Thus, the lnventlon pro-vldes, besldes two flxatlon parts to be flxed ln the bones on both sldes of the fractured ~olnt, an artlculatlng portion comprlslng curved, preferably cylindrlcally curved, slldlng surfaces; one of these surfaces ls convex and is a part of a ~'posltlve" element connected to one of sald flxatlon parts, and the other one ls concave and ls a part of a "negatlve" element connected to the other flxatlon part. When these surfaces sllde one over the other, one skllled ln the art easlly understands that the elements fixed to either surface wlll make a combined angular and longltu-dinal movement.
The concave surface is a part of a slldlng block whlchls able to sllde on a correspondlng convex surface ln the interlor of a houslng. This housing has a lateral closure, belng at a right angle to the axis of said curved surfaces. The closure and, preferably, the other lateral surface of the housing are provlded with a plurallty of stralght llnes having one point of lnter-sectlon outslde of the housing. Thls polnt of lntersectlon (and therefore the dlrectlon of sald llnes) ls selected so as to deflne the axls of the curvature of sald slldlng surfaces. Thls axls ls also the plvoting axls of the bone ~olnt. When the surgeon ~ -6- 1331549 applies the fixation device of the invention to the body, he will be able to aim at the joint axi~ in looking along said lines. He will very easily find said axis, even if the joint re~ion is swollen, and he has the possibility of readjusting, if possi~le, the fixaition device of this invention, as will be explained later.
The sliding block may be fixed by a screw which traverses a slot in the housing. This slot is curved and follows the curvature o' the sliding surfaces.
~nother screw, to be locked in said slot only, ser~Jes as a stop for limiting the movement of the sliding block in the housing. In the neighborhood of the slot, angle indications may be provided. The sliding sur-1 ~ faces m~y be c ~ er~ed by an antifrictional layer, forexample of te~e~ (PT~E) or nylon.
The materials of the instant fixation device will be selected to withstand repeated sterilization. This selection of materials is conventional for the man skilled in the art.
Furthermore, it is preferred to control the movement of the sliding block in the housing with regard to the force necessary for displacing the sliding block, in order to be able to establish a ; 25 suitable training or recovery program for the patient.
In one group of embodiments, the sliding block movement ~ is impeded by spring forces, be it a torsion spring or the elastic force of a rubber strip; in another embodi-ment, a frictional force is applied to said movement.
The amount of said frictional force may preferably be controlled between nearly zero to complete blocking.
Detailed Description of the Invention In order to explain the dynamic external bone fixation device of this invention in more detail, - : . ..
: ' .:`~
... -.. .. ~ . .... . . . i l .. - .... ~ . . . ... . . . . ..
~ -7- 1 33 1 54q several preferred embodiments thereof will be described with xeference to the attached drawings wherein:
FIGU~E 1 is a lateral elevational ~iew of a dynamic connection member showing the neutral position of the connection bars in full lines and their maximally perrnitted position in dotted lines.
FIGURE 2 is a longitudinal sectional view of the connection member of FIGURE 1, in a first embodiment including a spring to resist the patient's movement. -FI~URES ~ and 4 are partial views similar to PIGURE 2, showing embodiments where biasing means are respectively an elastic member and a frictional bxaXe~
FIGURE 5 is a perspective view of a dynamic external wrist fixation device comprising two groups of two pins each, these groups being connected to two corresponding bars,these bars being linked to the dynamic connection member.
FIGURE 6 is a section view taken alon~ line VI-VI
in ~IGURE 5, in an embodiment in which the pins are angulated at 40.
FIGURE 7 is a partial view, taken in sectlon along line VII-VII in ~IGURE 1, showing the connection me~er in a locked position. -FIGURE 8 is an enlarged detail of FIGURE 4 which illustrates an embodiment using a frictional brake to resist the patient's movement.
The dynamic external bone fixation device represented ~ --in PIGURES 1 and 2 comprises an articulating portion 1 ioining the rods 2 and 3.
As explained below, the rod 2 is to be connected ; to the pins fixed in the patient's metacarpus by means of a coupling schematized in 4. Similarly, the rod 3 is to be linked to the patient's radius by means of the coupling schematized in 5.
` \ -8-The articulatiny portion 1 is principally consti-tuted of a housing 6 and of a sliding block 7 which are both capable o~ sliding with respect to a sliding ~.
surface 8.
In other terms, the housing 6 presents a c~nvex sliding surface 8 whereas the sliding block 7 presents a corresponding concave sliding sur~ace. These sliding surfaces are for example cylindrical surfaces, the axes ~-of the corresponding cylinders being normal to the~
sliding plane of the articulating portion 1. In the drawings, this virtual axis is represented by A and corresponds to the axes of movement of tile f.actured wrist.
The housing 6 is realiz.ed either iIl a li~ht a loy or a synthetic material capable of withstanding steri- ~ -lization, since ali components of the device must be gas or steam autocl~ved. Th~ sliding block 7`i.s made, for example, of stainless steel.
The sliding surfaces 8 of the housillg 6 and/or of ~ ~:
the slid-ng block 7 comprise a slippery covering, not shown in the drawings, for instan~e nylon or teflon ; (PTFE).
W:;th reference to FIGURE 1 or 2, one will note that the general ~orm of the housing 6 is slightly curved according to the sliding surface 8. The inferior part of housing 6 pre~ents a curved face 9.
.. A pin lO fixes the extremity of the rod 2 in.the :~
sliding block 7. The extremity of the other rod 3, which is unthreaded, is fitted in a threadad:rod 11 and .. :~
. 30 is held in place with two knurled wheels 12 and 13, - ~ ~
allowing the adjustment in length of the unit .,:.. r.. ~.
comprising the articulating portion 1 and the rods 2 and 3, whereas any lateral displacement is avoided by means of the extending element 14. The othex extremity of the threaded rod 11 cooperates with the housing 6, ~ .
, ~
1 33 1 54q elther by dlrect screwlng, or by means o~ a pin 15, as illustrated ln FIGURE 2.
Another component of the artlculatlng portion 1 ls a lateral cover 16 whose general shape follows that of the houslllg 6. -~
The vlslble face of that lateral cover 16 presents a :~ :
scale 17 for the reading of relative angular movements between the slldlng block 7 and the houslng 6 and lts lateral cover 16. Some of the graduatlons of the rounded scale 17 are enlarged and ex- :
tended to form vlewlng llnes 18, almlng at the vlrtual axls A.
One could also envlsage disposlng vlewlng llnes on the slde of the housing opposite to the cover 16 (not visible ln the drawings). -~
The scale 17 and its corresponding mentloned numbers on the one hand and the vlewlng llnes 18 on the other can either be painted or engraved ln the cover and the houslng.
As shown in the detalled cross section of FIGURE 7, the slde of the houslng 6 faclng the lateral cover 16 presents an ~ ~-openlng 19 correspondlng to the slldlng block 7. As can be seen .~ :
ln FIGURE 2, the openlng 19 ls rounded to permlt the relatlve movement between housing 6 and sllding block 7. Identlcally, the .~ ~ :
cover 16 presents a rounded slot 20, the center of whlch ls also ~ :
In FIGURE 1, the slot 20 ls represented wlth two screws 21 and 22. The flrst ls a locking screw 21, preventlng any rela~
tlve movement between housing 6 and sliding block 7 (see FIGURE : -:
7). The second ls a limltlng screw 22, whlch is ad~usted on the cover along the scale 17, to llmlt the slot 20 and consequently sald relative movement, when the screw 21 ls unlocked.
In the first embodiment represented in FIGURE 2, the relatlve movement of houslng 6 and sliding block 7 X ~ .
-lo- 1331549 I is biased by a spring 23, an extremity of which is ! fixed in ~he hvusing 6 by a pin 24 while th2 other ~ -coop2rates ~ith the sliding block 7. II1 that embodi-ment, the opening 19 includes an extension 25 in which the spring 23 is localized in the position represented in full lin~s.
Although not shown in the drawings, an~ other torsion spring lin shape or disposition) may be used to directly or indi~ectly cooperate with both housing 6 and sliding block 7.
The means of impeding t,he movement o f block 7 within the housing 6 may alternatively be a rubber strip or ribbon 26, extending through both housing 6 and sliding block 7. In th~ embodiment presented in FIGURE 3, one free end of the rubber strip 26 is held by a metallic ring 27 taking rest on a flat surface 28 provided on the sliding block 7. The other end of the rubber strip 26 is directly fixed to the housing 6 from the outside, by means of a conical screw 29 Any other fixation of a rub'~er strip can also be ' ;~
- considered without extending beyond the scope of the present invention.
FIGURE 4 represents an embodir,ler~t u~sin~ a fric- '' tional brake, the force of which can be controlled. -' This frictional brake is composed principally of~ r~
a fixed part 30~,scre~ed into the ; housing 6, - a stuffing box screw 31, adapted to be ._ . , screwed on that fixed part 30, and = . , .~
- 30 - a piston rod 32, sliding in the-stuffing box screw 31, an extremity of which extends through the ~I fixed part 30 and cooperates with the sliding block 7, by means of a pin 33 entering in a corresponding opening provided in slidin~ block 7.
. . .
-~ .
As shown ln the detalled FIGURE 8, the flxed part 30 and the stufflng box screw 31 both present an extenslon, 34 and 35 respectlvely, lntended to cooperate with a serles of O-rlngs 36 and pressure rlngs 37 disposed around the plston rod 32. The sectlon of the pressure rlngs 37 presents an lnternal V-shape, the functlon of whlch wlll be explalned later on.
The plston rod 32 ls made of burnlshed stalnless steel or another well-pollshed materlal. The other components of thls embodlment are made of materlals capable of wlthstandlng sterlll-zatlon.
The flxed part 30 and the stufflng box screw 31 both present scales, 38 and 39 respectlvely, for readlng the amount of frlctlonal force. The lndlcatlons of scales 38 and 39 are elther -~
palnted or engraved. ;~
After the above descrlptlon of several embodlments of the present lnventlon, the posltlonlng of such a dynamlc external bone flxatlon devlce wlll now be explalned.
Wlth reference to FIGURE 5, the artlculatlng portlon ls schematlzed ln 1. Uslng the same reference numbers as ln the foregolng descrlptlon, the rods 2 and 3 are flxed ln the ball ~olnts 4 and 5, mounted on two clamps 40 and 41.
The base-plates 42 and 43 of the clamps 40 and 41 are covered by a flber-relnforced phenollc materlal to flrmly hold the serles of plns 44 and 45 dlsposed ln the metacarpus 46 and ln the radlus 47. One can remark that the base-plates 42 and 43 present holes fltted to exactly posltlon the plns 44 and 45.
Wlth reference to FIGURE 6, one can further remark that the flxatlon devlce ls very near to the ~~ -12- 1 33 1 549 fractured menlber, as the pins 44 are fixed in the second mGtacarpus 46 with an angulation up to 45, for clinical reasons which will be detailed later on.
With reference to FIGURE 5, the setting up of the device will be detailed.
According to well known techni~ues, at least two pins 44 are inserted in the second metacarpus 46. The pins 44 can be provided with continuous threads, having a self-drilling point at one end. The opposite end of the pins 44 is designed for secure insertion into a chuck, not represented in the drawings. The self-tapping thread provides maximum gripping power.
Alternatively, one can use non-self-drilling pins, which are inserted in pilot holes through both cortices. Of course, one can employ a guide to obtain the correct disposition of the pins 44. ~ ~
Both pins 44 in the metacarpus 46 are fixed in the ~ -ba~e~plate 42 of the clamp 40. .
After approximate alignment of the fracture, at least two pins 45 are similarly inserted in the radius -.~ . . .
i 47 and fixed in the base-plate 43 of the clamp ~1.
. . , Both clamps 40 and 41 are provided with ball joints 4 and 5 in which one can fix the extremities of the rods 2 and 3, by means of wing nuts 48 and 49.
When reducing the fracture, the practitioner disposes the device in the co~xect position ~y first centering the view lines 18 on the pivot axis of the joint and then fixing the device by means of the wing :~ nuts 48 and 49.
~ 30 An X-ray may then be taken to determine the .....
correct reduction of the fracture. If necessary, the wing nuts may be loosened and further manipulation may be carried out.
Further adjustment may be realized by means of the knurled wheels 12 and 13, which are first centered on :
. .
...... ., . ~... ~ ., " ,. ... ... . .
the threaded rod 11 and then dlsplaced to ensure the necessary extenslon. Durlng lnitlal heallng, the devlce ls blocked by means of locklng screw 21 (FIGURES l and 7).
As already mentloned ln the lntroductlon, lt ls deslr-able to glve progresslve motlon to the ~oint after an lnltial perlod when the devlce malntalns constant flxatlon of the frac- ~-tured member.
Wlthout glvlng a complete program, one can propose to control the amount of flexlon accordlng to the followlng table, ~:
1st week after fracture no movement 2nd " " " no movement 3rd " " " flexlon up to 10 4th " " " flexlon up to 20 5th " " " flexion up to 30 6th " " " flexlon up to 40 The amount of flexlon authorlzed wlll be determlned by the practltloner who wlll lock the llmltlng screw 22 ln the cor-responding posltlon. .
For lnstance ln FIGURE 1, the rotatlon ls llmlted by means of screw 22 to a rotatlon of 20, and consequently the rela-tlve movement of rods 2 and 3 takes place between the neutral posltlon represented ln full llnes and the maxlmum rotatlon posl-tlon, represented ln dotted llnes.
Referrlng to FIGURE 2, one can further note that ln the neutral posltlon, represented ln full llnes, the rods 2 and 3 are not allgned, but form an angle alpha of about 10. Thls ls due to the normal posltlon at rest of the wrlst. The angle of rotatlon beta represented ln thls flgure ls so comprlsed between 0 and 40.
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As alreaay mentioned, it is significant that the mov~ment during healing can be realized again~t the influence of a force.
In the embodiment proposed in FIGURES 2 and 3, this force is generally not linear, as neither the ~--spring 23 nor the elastic member 26 creates ~ reaction of equivalent force according to its position.
To further improve the device, the embodiment of FIGURE 4 ldetailed FIGURE 8) is proposed. In this version the movement is equally biased in both directions as the reactional foxce is du~ to the friction of the rod 32 against the O-rings ~6.
Furthermore this force can be regulated, either by the patient or by 'che practitioner, by turnin~ the stuffing box screw 31. Thus when the extensions 34 and - 35 come closer together, the O-rings 36 are pressed against the piston rod 32 as they are pressed between the rings 37 whose sectional shape is a V pointin~
towards the centerO Contrarily, the force ls reduced when the extensions are separated, as consequently the pressure of the O-rings is reduced~
The graduations of the scales 38 and 39 enable thP
reading vf the value of the friction. The scales 38 and 39 can be so graduated as to form a vernier.
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Claims (16)
1. A dynamic external bone fixation device for the osteosynthesis of a broken joint, comprising, (1) a first part comprising a first fixation rod having an axis a1 for connection to bone pins introduced into the bone on one side of said joint, (2) a second part comprising a second fixation rod having an axis a2 for connection to bone pins introduced into the bone on the other side of said joint, and (3) an articulating portion joining said first part and said second part, said articulating portion comprising:
(a) a first curved surface to which said first part is connected and which fits with a second curved surface to which said second part is connected so as to allow adjustably limited movement of said first part with respect to said second part, both said first curved surface and said second curved surface having a common virtual axis spaced apart from said device, and (b) means for locating said common virtual axis so that said virtual axis may be aligned with the axis of said joint, wherein said means for locating said virtual axis is an integral element of said device.
(a) a first curved surface to which said first part is connected and which fits with a second curved surface to which said second part is connected so as to allow adjustably limited movement of said first part with respect to said second part, both said first curved surface and said second curved surface having a common virtual axis spaced apart from said device, and (b) means for locating said common virtual axis so that said virtual axis may be aligned with the axis of said joint, wherein said means for locating said virtual axis is an integral element of said device.
2. The dynamic fixation device of claim 1 wherein said adjustably limited movement of said first part with respect to said second part is along an arc of a curve and wherein said articulating portion further comprises:
(a) a housing block fixed to said first fixation rod, said housing presenting said first curved surface and (b) a block fixed to said second fixation rod, said block presenting said second curved surface fitting with said first curved surface.
(a) a housing block fixed to said first fixation rod, said housing presenting said first curved surface and (b) a block fixed to said second fixation rod, said block presenting said second curved surface fitting with said first curved surface.
3. The dynamic fixation device of claim 2 wherein said first curved surface and said second curved surface are both portions of substantially cylindrical surfaces having substantially the same virtual axis and having substantially the same radius of curvature, wherein said axis a1 and said axis a2 are substantially coplanar, wherein said device is for the osteosynthesis of a broken wrist, and wherein said device permits motion substantially only in a single plane.
4. The dynamic fixation device of claim 2 further comprising means for limiting the angular sliding movement of said block within said housing.
5. The dynamic fixation device of claim 2 further comprising friction means for loading the sliding movement of said block with a controllable frictional force.
6. The dynamic fixation device of claim 5 wherein said friction means comprises: a piston rod fixed with one end thereof to said block; a bushing screwed into said housing; O-rings placed into said bushing and surrounding said piston rod; pressure rings inserted between two adjacent O-rings; and a stuffing box screw adapted to be screwed by hand into said bushing, thereby compressing said O-rings to a greater or lesser degree and thus controlling said frictional force.
7. The dynamic fixation device of claim 6 wherein said bushing and said stuffing box screw are provided with a vernier.
8. The dynamic fixation device of claim 2 wherein at least one of the curved surfaces of said housing and said block are provided with a slippery layer of material able to withstand repeated sterilizations.
9. A dynamic external bone fixation device for the osteosynthesis of a broken joint, comprising, (1) a first part comprising a first fixation rod having an axis a1 for connection to bone pins introduced into the bone on one side of said joint;
(2) a second part comprising a second fixation rod having an axis a2 for connection to bone pins introduced into the bone on the other side of said joint, and (3) an articulating portion joining said first part and said second part, said articulating portion comprising.
(a) a first curved surface to which said first part is connected and which fits with a second curved surface to which said second part is connected so as to allow adjustably limited movement of said first part with respect to said second part, both said first curved surface and said second curved surface having a common virtual axis spaced apart from said device, and (b) means for locating said common virtual axis so that said virtual axis may be aligned with the axis of said joint, wherein said means for locating said virtual axis is an integral element of said device, and wherein a housing block is fixed to said first fixation rod so that said housing presents said first curved surface, wherein a block is fixed to said second fixation rod such that said block presents said second curved surface which fits with said first curved surface, wherein said first curved surface and said second curved surface are cylindrical surfaces, the axis of the corresponding cylinder being normal to the sliding plane of the sliding block, and wherein said means for locating said virtual axis of said first curved surface comprises viewing lines on said device, and wherein said device comprises also a lateral cover which fits over said housing block and over said block fixed to said second fixation rod and which has a curved slot with a curvature corresponding to the curvature of said first curved surface and the curvature of said second curved surface.
(2) a second part comprising a second fixation rod having an axis a2 for connection to bone pins introduced into the bone on the other side of said joint, and (3) an articulating portion joining said first part and said second part, said articulating portion comprising.
(a) a first curved surface to which said first part is connected and which fits with a second curved surface to which said second part is connected so as to allow adjustably limited movement of said first part with respect to said second part, both said first curved surface and said second curved surface having a common virtual axis spaced apart from said device, and (b) means for locating said common virtual axis so that said virtual axis may be aligned with the axis of said joint, wherein said means for locating said virtual axis is an integral element of said device, and wherein a housing block is fixed to said first fixation rod so that said housing presents said first curved surface, wherein a block is fixed to said second fixation rod such that said block presents said second curved surface which fits with said first curved surface, wherein said first curved surface and said second curved surface are cylindrical surfaces, the axis of the corresponding cylinder being normal to the sliding plane of the sliding block, and wherein said means for locating said virtual axis of said first curved surface comprises viewing lines on said device, and wherein said device comprises also a lateral cover which fits over said housing block and over said block fixed to said second fixation rod and which has a curved slot with a curvature corresponding to the curvature of said first curved surface and the curvature of said second curved surface.
10. The dynamic fixation device of claim 9 wherein said lateral cover is provided with inscriptions indicating the angular displacement of said sliding block.
11. A dynamic external bone fixation device for the osteosynthesis of a broken joint, comprising:
(1) a first part comprising a first fixation rod having an axis a1 for connection to bone pins introduced into the bone on one side of said joint, (2) a second part comprising a second fixation rod having an axis a2 for connection to bone pins introduced into the bone on the other side of said joint, and (3) an articulating portion joining said first part and said second part, said articulating portion comprising.
(a) a first curved surface to which said first part is connected and which fits with a second curved surface to which said second part is connected so as to allow adjustably limited movement of said first part with respect to said second part, both said first curved surface and said second curved surface having a common virtual axis spaced apart from said device, and (b) means for locating said common virtual axis so that said virtual axis may be aligned with the axis of said joint, wherein said means for locating said virtual axis is an integral element of said device, and wherein a housing block is fixed to said first fixation rod so that said housing presents said first curved surface, wherein a block is fixed to said second fixation rod such that said block presents said second curved surface which fits with said first curved surface, wherein said dynamic fixation device further comprises means for biasing said block towards its rest position within said housing in which said first fixation rod and said second fixation rod form a small angle as compared with a straight line of up to about ?10°.
(1) a first part comprising a first fixation rod having an axis a1 for connection to bone pins introduced into the bone on one side of said joint, (2) a second part comprising a second fixation rod having an axis a2 for connection to bone pins introduced into the bone on the other side of said joint, and (3) an articulating portion joining said first part and said second part, said articulating portion comprising.
(a) a first curved surface to which said first part is connected and which fits with a second curved surface to which said second part is connected so as to allow adjustably limited movement of said first part with respect to said second part, both said first curved surface and said second curved surface having a common virtual axis spaced apart from said device, and (b) means for locating said common virtual axis so that said virtual axis may be aligned with the axis of said joint, wherein said means for locating said virtual axis is an integral element of said device, and wherein a housing block is fixed to said first fixation rod so that said housing presents said first curved surface, wherein a block is fixed to said second fixation rod such that said block presents said second curved surface which fits with said first curved surface, wherein said dynamic fixation device further comprises means for biasing said block towards its rest position within said housing in which said first fixation rod and said second fixation rod form a small angle as compared with a straight line of up to about ?10°.
12. The dynamic fixation device of claim 11 wherein said biasing means comprises an elastomer strip fixed with one end to the housing and with the other end to said block.
13. The dynamic fixation device of claim 11 wherein said biasing means comprise a spring inserted between said block and said housing.
14. A dynamic external bone fixation device for the osteosynthesis of a broken joint, comprising, (1) a first part comprising a first fixation rod for connection to bone pins introduced into the bone on one side of said joint, (2) a second part comprising a second fixation rod for connection to bone pins introduced into the bone on the other side of said joint, and (3) an articulating portion joining said first part and said second part, said articulating portion comprising:
(a) curved sliding surface adapted to allow adjustably limited movement of said first part with respect to said second part, said sliding surface having a virtual axis spaced apart from said device, and (b) means for locating said virtual axis of said curved sliding surface so that said virtual axis may be aligned with said joint, wherein said means for locating said virtual axis is an integral element of said device, and wherein (1) a housing block is fixed to said first fixation rod, said housing block presenting a convex sliding surface, and (2) a sliding block is fixed to said second fixation rod, said sliding block presenting a concave sliding surface fitting with said convex sliding surface, and (3) a lateral cover is present having a curved slot with a curvature corresponding to that of said two sliding surfaces, and wherein said sliding block is fixed to said second fixation rod by means of a pin.
(a) curved sliding surface adapted to allow adjustably limited movement of said first part with respect to said second part, said sliding surface having a virtual axis spaced apart from said device, and (b) means for locating said virtual axis of said curved sliding surface so that said virtual axis may be aligned with said joint, wherein said means for locating said virtual axis is an integral element of said device, and wherein (1) a housing block is fixed to said first fixation rod, said housing block presenting a convex sliding surface, and (2) a sliding block is fixed to said second fixation rod, said sliding block presenting a concave sliding surface fitting with said convex sliding surface, and (3) a lateral cover is present having a curved slot with a curvature corresponding to that of said two sliding surfaces, and wherein said sliding block is fixed to said second fixation rod by means of a pin.
15. A dynamic external bone fixation device for the osteosynthesis of a broken joint, comprising: (1) a first part comprising a first fixation rod for connection to bone pins introduced into the bone on one side of said joint, (2) a second part comprising a second fixation rod for connection to bone pins introduced into the bone on the other side of said joint, and (3) an articulating portion joining said first part and said second part, said articulating portion comprising, (a) a curved sliding surface adapted to allow adjustably limited movement of said first part with respect to said second part, said sliding surface having a virtual axis spaced apart from said device, and (b) means for locating said virtual axis of said curved sliding surface, wherein said means for locating said virtual axis is an integral element of said device, and wherein (1) a housing block is fixed to said first fixation rod, said housing block presenting a convex sliding surface, and (2) a sliding block is fixed to said second fixation rod, said sliding block presenting a concave sliding surface fitting with said convex sliding surface, wherein said articulating portion has a lateral cover having a curved slot with a curvature corresponding to that of said two sliding surfaces, wherein said dynamic fixation device further comprises friction means for loading the sliding movement of said sliding block with a controllable frictional force, wherein said friction means comprises: a piston rod fixed with one end thereof to said sliding block; a bushing screwed into said housing; O-rings placed into said bushing and surrounding said piston rod; pressure rings inserted between two adjacent O-rings; and a stuffing box screw adapted to be screwed by hand into said bushing, thereby compressing said O-rings to a greater or lesser degree and thus controlling said frictional force.
16. A dynamic fixation device according to claim 15, wherein said bushing and said stuffing box screw are provided with a vernier.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/863,756 US4919119A (en) | 1986-05-20 | 1986-05-16 | External dynamic bone fixation device |
| CA000509457A CA1331549C (en) | 1986-05-20 | 1986-05-20 | External dynamic bone fixation device |
| JP61123216A JPS62286455A (en) | 1986-05-20 | 1986-05-28 | Dynamic bone fixing external apparatus |
| DE8614898U DE8614898U1 (en) | 1986-05-20 | 1986-06-03 | |
| EP86810242A EP0248138B1 (en) | 1986-05-20 | 1986-06-05 | External dynamic bone fixation device |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000509457A CA1331549C (en) | 1986-05-20 | 1986-05-20 | External dynamic bone fixation device |
| JP61123216A JPS62286455A (en) | 1986-05-20 | 1986-05-28 | Dynamic bone fixing external apparatus |
| EP86810242A EP0248138B1 (en) | 1986-05-20 | 1986-06-05 | External dynamic bone fixation device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1331549C true CA1331549C (en) | 1994-08-23 |
Family
ID=27167604
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000509457A Expired - Fee Related CA1331549C (en) | 1986-05-20 | 1986-05-20 | External dynamic bone fixation device |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4919119A (en) |
| EP (1) | EP0248138B1 (en) |
| JP (1) | JPS62286455A (en) |
| CA (1) | CA1331549C (en) |
| DE (1) | DE8614898U1 (en) |
Families Citing this family (40)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB8807026D0 (en) * | 1988-03-24 | 1988-04-27 | Sheffield City Council | Bone fixation |
| FR2632515A1 (en) * | 1988-06-10 | 1989-12-15 | Michael S France | External surgical joint fixator |
| CH680769A5 (en) * | 1989-08-23 | 1992-11-13 | Jaquet Orthopedie | |
| IT1244249B (en) * | 1990-08-03 | 1994-07-08 | Ascanio Campopiano | MANIPULATOR FOR THE EXECUTION OF REDUCING MANEUVERS IN USE IN TRAUMATOLOGICAL AND ORTHOPEDIC MEDICINE APPLICABLE TO EXTERNAL FIXATORS. |
| FR2667781B1 (en) * | 1990-10-12 | 1994-01-21 | Materiel Orthopedique Cie Gle | EXTERNAL FIXATION AND REDUCTION OF BONE FRACTURES. |
| JP3380243B2 (en) * | 1992-08-24 | 2003-02-24 | ジンテーズ アクチエンゲゼルシャフト，クール | External fixation device for osteosynthesis |
| US5391167A (en) * | 1992-09-01 | 1995-02-21 | Ortho-Motion, Inc. | Articulating external fixation device |
| WO1994010947A1 (en) * | 1992-11-10 | 1994-05-26 | Innovative Orthopaedics Manufacturing, Inc. | Dynamic external fixator for the wrist |
| US5358504A (en) * | 1993-05-05 | 1994-10-25 | Smith & Nephew Richards, Inc. | Fixation brace with focal hinge |
| DE9419514U1 (en) * | 1994-12-06 | 1995-03-30 | Orthomed Chirurgische Instr Gm | Device for fixing an elbow |
| US5595563A (en) * | 1995-09-05 | 1997-01-21 | Moisdon; Roger G. F. | Method and apparatus for maintaining the position of body parts |
| US5846245A (en) * | 1995-10-20 | 1998-12-08 | New York University | Bone-adjusting device |
| DE29619711U1 (en) | 1996-11-13 | 1998-03-12 | Synthes Ag | Device for repositioning bone fracture fragments |
| US6027504A (en) * | 1996-12-06 | 2000-02-22 | Mcguire; David A. | Device and method for producing osteotomies |
| US5897555A (en) * | 1997-05-15 | 1999-04-27 | Wright Medical Technology, Inc. | External fixation system and method |
| US5928234A (en) * | 1997-10-10 | 1999-07-27 | Manspeizer; Sheldon | External fixture for tracking motion of a joint |
| ES2284204T3 (en) | 1998-05-19 | 2007-11-01 | Synthes Gmbh | CLAMP FOR AN EXTERNAL MONOLATERAL FIXING SYSTEM FOR TRAUMATOLOGY AND ORTHOPEDIA. |
| US6030391A (en) * | 1998-10-26 | 2000-02-29 | Micropure Medical, Inc. | Alignment gauge for metatarsophalangeal fusion surgery |
| US6245071B1 (en) | 1999-03-10 | 2001-06-12 | Synthes (U.S.A.) | External fixation device for bone |
| GB0107708D0 (en) * | 2001-03-28 | 2001-05-16 | Imp College Innovations Ltd | Bone fixated,articulated joint load control device |
| FR2823093B1 (en) * | 2001-04-04 | 2003-12-19 | Newdeal Sa | GUIDE FOR ANGULAR POSITIONING OF THE BONES OF A JOINT WITH A VIEW TO ACHIEVING AN ARTHRODESIS |
| US6709433B1 (en) * | 2001-12-20 | 2004-03-23 | Biomet, Inc. | Bridging/non-bridging external bone fixator |
| US7367977B2 (en) * | 2002-02-28 | 2008-05-06 | Estrada Jr Hector Mark | Apparatus for dynamic external fixation of distal radius and wrist fractures |
| JP4028552B2 (en) * | 2002-11-19 | 2007-12-26 | アキュームド・エルエルシー | Adjustable bone plate |
| US6953313B2 (en) * | 2003-06-26 | 2005-10-11 | Gordon Tylosky | Self-locking linear adjustment mechanism |
| US7887567B2 (en) * | 2003-10-06 | 2011-02-15 | Mazer Surgical Technologies, Ltd. | Apparatus for spinal fixation of vertebrae |
| US20060229605A1 (en) * | 2005-03-18 | 2006-10-12 | Olsen Ron A | Adjustable splint for osteosynthesis with incrementing assembly for adjustment in predetermined increments |
| US7575575B2 (en) * | 2005-03-18 | 2009-08-18 | Ron Anthon Olsen | Adjustable splint for osteosynthesis with modular components |
| US7722609B2 (en) | 2005-04-25 | 2010-05-25 | Synthes Usa, Llc | Outrigger with locking mechanism |
| US7507215B2 (en) | 2005-07-08 | 2009-03-24 | Jri Development Group, Llc | Orthotic brace |
| US7731738B2 (en) * | 2005-12-09 | 2010-06-08 | Orthopro, Llc | Cannulated screw |
| FI122920B (en) * | 2009-10-05 | 2012-08-31 | Aalto Korkeakoulusaeaetioe | Anatomically personified and mobilizing external support, method of manufacture thereof and the use of a portion of the invasively attached support for determining the path of movement of the joint to be supported |
| US9737336B2 (en) | 2009-10-05 | 2017-08-22 | Aalto University Foundation | Anatomically personalized and mobilizing external support and method for controlling a path of an external auxiliary frame |
| ITBO20120576A1 (en) * | 2012-10-23 | 2014-04-24 | Citieffe Srl | ARTICULATED JOINT FOR ORTHOPEDIC DEVICES |
| US9827011B2 (en) | 2013-03-15 | 2017-11-28 | Biomet Manufacturing, Llc | Polyaxial pivot housing for external fixation system |
| ITMI20130409A1 (en) * | 2013-03-18 | 2014-09-19 | Orthofix Srl | ARTICULATED DEVICE FOR WRIST |
| US9962188B2 (en) | 2013-10-29 | 2018-05-08 | Cardinal Health 247. Inc. | External fixation system and methods of use |
| EP3164093B1 (en) | 2014-07-03 | 2024-02-14 | Acumed LLC | Bone plate with movable joint |
| CN106308903A (en) * | 2014-10-24 | 2017-01-11 | 烟台小米机械技术有限公司 | Hand bone fixator with small size |
| US11653951B2 (en) * | 2018-11-06 | 2023-05-23 | Ali Moradi | External orthopedic fixation device |
Family Cites Families (36)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US31809A (en) * | 1861-03-26 | Improvement in fire-arms | ||
| US1997466A (en) * | 1934-04-23 | 1935-04-09 | Harry Herschel Leiter | Surgical appliance |
| US3779654A (en) * | 1971-08-06 | 1973-12-18 | R Horne | Artificial joint |
| US3941123A (en) * | 1975-05-20 | 1976-03-02 | Mstislav Vasilievich Volkov | Apparatus for joint movement restitution |
| JPS5246429A (en) * | 1975-10-09 | 1977-04-13 | Jeol Ltd | Direct current high voltage power source |
| DE2745504A1 (en) * | 1977-10-10 | 1979-04-19 | Erich Strickle | DEVICE FOR RESTING OR SUPPORTING LIMBS OF PEOPLE AND ANIMALS |
| US4185623A (en) * | 1978-07-18 | 1980-01-29 | Oganesian Oganes V | Apparatus for restoration of hip joint mobility |
| GB2026321B (en) * | 1978-07-27 | 1982-12-01 | Tsnii Travmatol I Ortoped Im N | Apparatus for restoration of hip joint mobility |
| ES253459Y (en) | 1978-11-10 | 1982-04-16 | EXTERNAL CLINICAL FIXER, OF HIGH STABILITY, TO REDUCE FRACTURES. | |
| CH630798A5 (en) | 1979-01-16 | 1982-07-15 | Jaquet Orthopedie | EXTERNAL FIXER FOR OSTEOSYNTHESIS. |
| SU888978A1 (en) * | 1980-04-02 | 1981-12-15 | Харьковский Научно-Исследовательский Институт Ортопедии И Травматологии Им. Проф. М.И.Ситенко | Apparatus for treating finger phalanx fractures |
| US4356624A (en) | 1980-08-07 | 1982-11-02 | Lyall Electric, Inc. | Fabrication techniques for tubular sheathed heaters |
| US4393868A (en) * | 1981-02-20 | 1983-07-19 | Ace Orthopedic Manufacturing Inc. | Colles fracture fixature device |
| US4337764A (en) * | 1981-03-02 | 1982-07-06 | United States Manufacturing Company | Adjustable motion brace |
| US4370977A (en) * | 1981-05-04 | 1983-02-01 | Kenneth D. Driver | Knee and elbow brace |
| US4440159A (en) * | 1981-06-29 | 1984-04-03 | Cochran Phillip E | Veterinary appliance for use on a front leg of a small animal |
| US4397308A (en) * | 1981-07-23 | 1983-08-09 | Therapeutic Appliances, Inc. | Adjustable splint |
| US4548199A (en) * | 1981-11-13 | 1985-10-22 | Agee John M | Fracture splint |
| NO149831C (en) * | 1981-11-27 | 1984-07-04 | Per Helland | EXTERNAL CORRECTION AND FIXING EQUIPMENT OF THE KNOCKS |
| ES8302449A2 (en) * | 1981-12-09 | 1983-01-16 | Lazo De Zbikowski Juan | Functional attachment system for osteosynthesis |
| US4637382A (en) * | 1982-04-27 | 1987-01-20 | Brigham & Women's Hospital | Motion-guiding load-bearing external linkage for the knee |
| US4696293A (en) * | 1982-09-30 | 1987-09-29 | Ciullo Jerome V | Hinged external fixator |
| US4554915A (en) * | 1983-03-08 | 1985-11-26 | Richards Medical Company | Bone fixation frame |
| ES8506138A1 (en) * | 1983-07-25 | 1985-07-01 | Stanadyne Inc | Electronic fuel control system for a fuel injection pump. |
| US4628919A (en) * | 1983-09-09 | 1986-12-16 | Clyburn Terry | Dynamic external fixator and method of use |
| US4620532A (en) * | 1983-09-26 | 1986-11-04 | Lenox Hill Brace Shop, Inc. | Adjustment device for an articulated joint brace |
| US4523585A (en) * | 1983-10-03 | 1985-06-18 | Lamb Steve R | Anatomic fracture brace for the knee |
| US4611586A (en) * | 1983-10-06 | 1986-09-16 | John M. Agee | Articulated Colles' fracture splint |
| IT1183735B (en) * | 1984-02-13 | 1987-10-22 | Orthofix Srl | ARTICULATED EXTERNAL MINIFIXER |
| US4643177A (en) * | 1984-06-13 | 1987-02-17 | University Of Florida | Dynamic traction wrist cast brace |
| GB8424579D0 (en) * | 1984-09-28 | 1984-11-07 | Univ London | Fracture reduction apparatus |
| US4612919A (en) * | 1984-10-03 | 1986-09-23 | Best Walter E | Adjustable limb support |
| US4618147A (en) * | 1985-07-02 | 1986-10-21 | Accuswing, Incorporated | Bowling glove |
| US4730608A (en) * | 1986-03-05 | 1988-03-15 | Schlein Allen P | External bone-anchoring fixator |
| US4699129A (en) * | 1986-09-05 | 1987-10-13 | Aaserude Gordon V | Polycentric variable axis hinge |
| US4782842A (en) * | 1987-02-02 | 1988-11-08 | Fietti Jr Vincent G | Arcuate fixator |
-
1986
- 1986-05-16 US US06/863,756 patent/US4919119A/en not_active Expired - Lifetime
- 1986-05-20 CA CA000509457A patent/CA1331549C/en not_active Expired - Fee Related
- 1986-05-28 JP JP61123216A patent/JPS62286455A/en active Granted
- 1986-06-03 DE DE8614898U patent/DE8614898U1/de not_active Expired
- 1986-06-05 EP EP86810242A patent/EP0248138B1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62286455A (en) | 1987-12-12 |
| DE8614898U1 (en) | 1987-01-15 |
| EP0248138A1 (en) | 1987-12-09 |
| US4919119A (en) | 1990-04-24 |
| JPH0468945B2 (en) | 1992-11-04 |
| EP0248138B1 (en) | 1991-04-03 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |