PT92490B - OSTEOSSINTESE APPLIANCE - Google Patents

Abstract

The present invention relates to traumatology and orthopaedics. An apparatus for osteosynthesis comprises a frame, each of two parallel walls 3, 4 thereof having a longitudinal recess 5, and at least four repositioning units, each of them including a slide 6, a rod 15 and a support element. According to the invention each of the support elements is configured as a spacing sleeve 8, having a male thread 9 and keyways, which are located near the ends of the sleeve. A set screw 12 passes through a hole in the spacing sleeve 8 and through the longitudinal recesses 5 in the walls of the frame 3, 4. <IMAGE>

Description

DESCRIPTIVE MEMORY

The present invention relates to traumatology and more specifically to an osteosynthesis apparatus. Current surgical practice uses rod-type devices for osteosynthesis of bone fragments, consisting of a support element, rods and clamping units for fixing the rods to the support element, an osteosynthesis device is known in the present art (US, A , 4,570,625), comprising a support element which is presented as a solid bar supporting a number of clamping units capable of longitudinal movement and fixation, each of said fixing units having a rod mounted and locked in place in it and rotated, with its own conical portion, within a respective bone fragment. Each of the bone fragments is fixed on two rods arranged in parallel. The smooth bar is equipped with a device for longitudinal movement of the two rods attached to the same bone fragment, so that the gradual distraction or compression of the bone fragments is ensured. However, the device being explained is unable to provide a gradual displacement (repositioning) of the bone fragments in a transversal plane, as well as in inclined planes, which places limitations in the field of application of the device. A prior art osteosynthesis apparatus (SU, A, 1 395 303) is known and comprises an oblong frame in which, each of the two parallel longitudinal walls has a longitudinal recess, and at least four repositioning units. Each of the repositioning units incorporates a cursor equipped with two crossed holes, one longitudinal and one transverse, a support element mounted in the transverse hole of the cursor with a possibility of longitudinal displacement and fixation in the longitudinal recesses of the longitudinal walls of the frame, and rod having its own taper and a threaded portion and fixed in the longitudinal hole of the cursor with a possibility of axial displacement and fixation. Each of the support elements is formed with a threaded bar. To provide a rigid construction the frame has walls whose cross-sectional profile is shaped like an angle.

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The apparatus described above is capable of imparting a gradual displacement of bone fragments along orthogonal directions in a transverse plane in any position. However, said known apparatus is unable to provide the replacement of bone fragments within six degrees of freedom. In addition, it is difficult to install the rods on the bone fragments in said apparatus, which is explained by the need for strict parallelism of the rods and difficulties encountered in fitting the threaded bars within the longitudinal frame recesses.

It is a main and essential objective of the present invention to provide an osteosynthesis apparatus, having such a constructive arrangement of each repositioning unit that the assembly time of the apparatus would be considerably reduced, during surgery, and the time for its removal after surgery. it also allows the replacement of some individual re-recycling units without removing the frame and extending the functional capabilities of the device. The said objective is achieved due to the fact that in an osteosynthesis apparatus, comprising an oblong frame, each of its two parallel longitudinal walls having a longitudinal recess, and at least four repositioning units, each incorporating a slide provided with two crossed holes, that is, one longitudinal and one transversal, a support element installed in the transversal hole of the slide with a possibility of longitudinal displacement and fixation in the longitudinal recesses of the longitudinal walls of the frame, and a rod having its own taper and a threaded portion, said rod being inserted in the longitudinal hole of the slide with a possibility of axial displacement and fixation, according to the invention, each of the support elements is formed as a spacer sleeve having a male thread and slots for a key, said slits being located near the end of the sleeve adapted to interact with the inner surface of the side walls of the frame, while a fixing screw is passed through the hole in the spacer sleeve and through the longitudinal recesses in the longitudinal walls. 338 338

0802/2 Ρ. 117205-Μ-68 —4— in the frame, it is convenient that the longitudinal walls of the frame are flattened. Such a constructive arrangement of the frame walls gives them the required elasticity in the plane of the frame arrangement. In addition, the flattened walls of the frame make it possible to install and remove each of the repositioning units, regardless of the position taken by the remaining units, which adds to the functional capabilities of the device and reduces its installation time.

it is convenient that the transverse slide hole is threaded and that the spacer sleeve is rotated within said threaded hole.

Such a constructive arrangement simplifies the construction of the repositioning unit due to the screwing of a locking nut on the spacer sleeve, when compared to the prototype which results in a lower mass of the device, reduces the amount of its component parts and reduces the time of installation of the device due to the shorter time required to fix the repositioning unit on the frame.

it is convenient to provide a slide with a sliding nut whose body is convenient to be installed with a possibility of free rotation in the longitudinal sliding hole, while the rod is reasonably to be rotated, with its threaded portion inside the sliding nut. Such a constructive feature adds to the convenience in adjusting the rods in the frame due to the fact that external access to the fastening elements is provided, although in the case with the prototype in which a key had to be manipulated in a restricted space between the frame and the frame. patient's body, as well as reducing the installation time of the device.

To increase the functional capabilities of the device due to the replacement of bone fragments along inclined directions in the transverse planes of the frame, it is convenient that the displacement nut is installed in the slide with a possibility of angular displacement in the transverse plane of the frame.

Such installation of the sliding nut also simplifies

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-5ο installation process of the rod since the requirement of mandatory parallelism of the rods in the bone fragments is no longer necessary. In addition, there are adequate securing of the rods to the frame, regardless of their orientation in relation to the frame as well as reducing the time for installing the device. To increase the functional capabilities of the device due to the possibility of fixing and repositioning the bone fragments of the femoral neck and fixing a bone fragment with a single cantilever rod maintained in relation to the frame, it is convenient that the device be equipped with a fixation of a bone fragment of the femoral neck, comprising a body with two parallel complementary cross holes, a clamping screw that is passed through each of the said complementary holes and through longitudinal recesses in the longitudinal walls of the frame, and a central hole in which the body of the sliding nut is adjusted with a possibility of free rotation with the axis of said central hole disposed at an angle of 120 to 130 ° with respect to the frame plane and a rod rotated inside the sliding nut with its threaded portion .

it is convenient that a cylindrical recess having a length equal to 0.5 or 0.8 of the length of the proper taper rod portion and a depth equal to 0.2 or 0.6 of the thread depth is provided in the rod portion proper taper near the end of the rod.

Such a constructive arrangement of the proper taper rod portion adds to the rigidity of its fixation in the cortical layer of a tubular bone which is taken into account by compensating for the widening of the initial orifice during rotation of the rod with a smaller diameter thread due rotation of the larger diameter threaded root portion.

it is convenient to provide the apparatus with at least one emergency fixing unit comprising two spacer sleeves installed with a possibility of longitudinal displacement and fixation and provided with a clamping screw that passes through the device.

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-6 through the hole of each of the said spacer sleeves and through the longitudinal recesses in the longitudinal walls of the frame, while each of the said spacer sleeves supports a slide with a collar clamp that supports a smooth stepped rod being said slide capable of rotate in relation to said spacer sleeve.

Such a constructive feature increases the functional capabilities of the device due to the provision of emergency fixation of bone fragments under field conditions, which are necessary for the transport of patients to a hospital. The application of smooth staggered rods makes it possible to expeditiously fix bone fragments, which in turn increases the surgeon's work productivity and ensures the admission of patients to the hospital without additional injuries to them during transit.

it is favorable that the longitudinal recess in each of the longitudinal walls of the frame accommodate at least one bridge subdividing the longitudinal recesses in portions.

Such a constructive feature adds to the stiffness of the frame walls in a longitudinal plane and simplifies the construction of the apparatus by dispensing with the elements for fixing the spacer sleeves such as C washers, as well as making it possible to achieve higher fixation stiffness of the bone fragments and faster installation of the device.

it is advisable to provide the apparatus with a device for the longitudinal adjustable displacement of bone fragments, which should comprise a U-shape, having longitudinal grooves in its side walls, said grooves being adapted to accommodate and fix the clamping screws of at least two repositioning units and means to provide longitudinal movement to the U-piece while the heads of said clamping screws should be provided with threaded bosses.

The provision of such a device extends the functional capabilities of the device due to an adjustable longitudinal displacement of the bone fragments. In fact, the proposed construction of dis70 338

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The device adds to the convenience of supporting the device by the patient due to the possibility of removing said device from the device after performing a next adjusted displacement of the bone fragments. Such a constructive arrangement of the device for an adjustable longitudinal displacement of the bone fragments, allows it to be used in a variety of osteosynthesis devices.

In order to provide an adjustable longitudinal displacement of the bone fragments and to speed up the installation of the device described above in the frame, it is necessary that the means of longitudinal movement of the U-piece be provided with a detachable clamp adapted to be installed in the frame's end wall and with a adjustment screw that would be adjusted in a threaded hole provided in the middle portion of the U-piece and be adapted to interact, through its end, with the detachable clamp.

Osteosynthesis apparatus, according to the invention, provides mutual repositioning of bone fragments with six degrees of freedom and makes it possible to avoid any kind of displacement of bone fragments, followed by their fixation until complete consolidation. The proposed device ensures an adjustable displacement of bone fragments in three orthogonal directions, including distraction and graduated compression. The present apparatus is also applicable for osteosynthesis of fragments of tubular bones in closed and open fractures of the limbs, in fractures aggravated by osteomyelitis, in the treatment of pseudoarthrosis, in the correction of osteotomies, in the treatment of genicular or talocrural arthrosis, for the repair bone defects with or without soft tissue plastic surgery, for reimplantation of limb segments, or in the treatment of femoral neck fractures.

In what follows the present invention is illustrated by a detailed description of some specific exemplary embodiments thereof with reference to the accompanying drawings, in which:

figure 1 is a view of the osteosynthesis apparatus, according to 338

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-δύο with ο invention;

figure 2 is a top view of figure 1;

figure 3 is a longitudinal sectional view of a spacer sleeve according to the invention;

figure 4 is a section on line IV-IV in figure 1;

figure 5 is a section on line V-V in figure 1;

figure 6 is a generic view of a rod;

figure 7 is an enlarged view of the taper rod portion according to the invention;

figure 8 is a section on line VIII-VIII of figure 7;

figure 9 is a generic view of a slider with a sliding nut according to the invention;

figure 10 is a front view of arrow A in figure 9;

figure 11 is a first embodiment of the repositioning unit, in which its cursor supports the sliding nut according to the invention;

figure 12 is a second embodiment of the repositioning unit, in which its cursor supports the sliding nut according to the invention;

figure 13 represents an osteosynthesis apparatus according to the invention incorporating an emergency fixation unit;

figure 14 is a section on line XIV-XIV in figure 13;

figure 15 is a section along line XV-XV in figure 14;

figure 16 is a front view of the arrow B in figure 13;

figure 17 is a view of a femoral neck fragment fixation unit, according to the invention;

figure 18 is a front view of the arrow C in figure 17;

figure 19 is an embodiment of a longitudinal recess having a single bridge, according to the invention;

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Fig. 20 shows a longitudinal recess of Fig. 19 provided with two bridges;

figure 21 represents an osteosynthesis apparatus according to the invention, incorporating a device for adjustable longitudinal displacement of two bone fragments;

figure 22 is a front view of the arrow D of figure 21;

figure 23 is a section along line XXIII-XXIII in figure 22;

figure 24 is a section along line XXIV-XXIV in figure 23; and figure 25 is a section along line XXV-XXV in figure 22.

The osteosynthesis apparatus according to the invention comprises an oblong frame 1 (figure 1) and at least four repositioning units 2. Two longitudinal walls of the frame 1, that is, wall 3 (figure 2) and wall 4 are flat and parallel to each other. Each of the longitudinal walls 3 and 4 has a longitudinal recess 5 (figure 5).

Each of the repositioning units 2 comprises a cursor 6 (figure 2), which has two crossed holes, one longitudinal and the other transversal. The transverse hole of the cursor 6 accommodates a support element 7 mounted with a possibility of longitudinal displacement and fixation in the longitudinal recesses 5 (figure 1) of the longitudinal walls 3, 4 (figure 2) of the frame 1. Each of the support elements 7 it is shaped like a spacer sleeve 8 (figure 3) provided with a male thread 9 and key slots 10, said slots close to the ends of the sleeve being adapted to interact with the inner surface of the longitudinal surfaces 3 (figure 4) and 4. One clamping screw 12 (figure 4) is passed through a hole 11 (figure 3) in each of the spacer sleeves 8 and through the longitudinal recesses 5 (figure 4) of frame 1 (figure 1), said clamping screw being blocked by a nut 13 from the outside.

cross hole in cursor 6 can be flat in which case cursor 6 is locked in position on spacer sleeve 8 with _ —1¾

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-10two nuts 14. On the other hand, the cross hole of the cursor 6 can be threaded which is the case shown in figure 5. In such a case the spacer sleeve 8 is to be rotated inside said hole while the cursor 6 is locked in place in the spacer sleeve 8 only with a nut 14, which provides a simpler construction (due to the smaller number of nuts 14), reduces the transverse dimensions of the device (due to the thickness of the nut 14) and therefore reduces the installation time of the device.

A rod 15 is fitted in the longitudinal hole of each cursor 6 with the possibility of axial displacement, said rod being locked in the cursor 6 by means of two nuts 16, 17.

The rod 15 is formed as a sequence of the following portions: a conical portion 18 (figure 6), a smooth portion 19, a threaded portion 20 and a back piece 21, having a polyhedral cross section for wrench. The working end of the proper taper portion 18 is blunt as for example a tapered trunk, a rounded tip or any other shape with a reduced dimension along an axis 22 (figure 7). Thread 23 of the proper taper portion 18 forms a tapered recess at an angle of 10 to 15 ° to axis 22 of rod 15 and a cylindrical recess 25 for a depth of 0.2 to 0.6 of the depth of thread 23 The depth of the tapered recess 24 equals the depth H of the thread 23 at the end of the rod 15. The length L of the cylindrical recess 25 is equal to 0.5 to 0.8 of the length L of the taper portion 18, which has a number (3 to 4) of longitudinal slots 26 (figure 8) having depth H (figure 7) of thread 23. Slots 26 can be square, triangular, trapezoidal or any other section, either with a straight line or bottom arcuate, the latter having a radius R equal to the radius of the side cutter with the aid of which the slot was milled. The slots 26 are longer than the conical recesses 24, since it is necessary to provide the formation of the cutting phases 27 (figure 8) of the thread 23 (figure 7), both in the conical recesses 24 and in the initial portion of the cylindrical recess 25. In individual cases the length a of the slots 26 po / r

7Q 338

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-lide to be equal to the length L of the proper taper portion 18, which facilitates the rotation of the latter in the first cortical layer of a bone 28 (figure 6).

device is installed as follows.

Preliminarily a first hole 29 (figure 6) is drilled in the first cortical bone layer coaxially with a second hole that is drilled in the second cortical layer, with both holes having a diameter D equal to D = D. - 2h (figure 7). When the rod 15 is rotated by means of a socket wrench, inside the first hole 29, the bezel faces 27 (figure 7) of the turns of the thread 23 remove bone chips from the faces of the hole 29 (figure 6) to form a channel shallow depth within which the rod 15 is suitably free to rotate a length a (figure 7) of the cylindrical recess 25. Since the rod is selected previously having a length L in its own taper portion 18 equal to the diameter of the bone 28 (figure 6), so that during the additional rotation of the rod 15 inside the bone, the complete profile portion of the thread 23 (figure 7) approaches the first hole 29, simultaneously with the approach of the end of the rod 15, having the conical recess 24 (figure 7), of the second hole 30 (figure 6). Thus, a helical groove is formed in the second hole 30 (figure 6) simultaneously with the deepening of the helical groove in the first hole 29. Consequently, the end of the rod 15 is tightened and rigidly fitted in the second hole 30. The blunt end of the rod 15 it goes beyond the second cortical layer of bone 28 to a depth of just 2 or 3 mm which inflicts less damage to soft tissues when compared to known rods.

The installation process of the rod 15 does not require high precision drilling of the holes 29 and 30 in the bone 28 since a suitably large depth h (figure 71 of the thread 23 and the fact that the turns of the thread 23 fit tightly to the faces of the helical canal of bone 28 (figure 6), across the entire width of it makes it possible to provide quite high stiffness

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in

-12 of the attachment of the rod 15 even when the orifice diameters 29 30 are somewhat enlarged due to the radial deviation of the drilling path. It is not necessary in a particular case to use countersinks for a precise establishment of holes 29 and 30, which considerably reduces the installation time of the rod 15. This is due to the fact that, for example, four longitudinal slots 26 (figure 8) are spaced evenly along the periphery of the thread 23 (figure 7) and made appropriately narrow, so that the resistance of the remaining portion of the thread 23 (figure 7) does not cut underneath the root and the rigid fixation of the rod 15 in the bone 28 ( figure 6) is obtained even at the location of the grooves 26 (figure 7).

Once the rods have been installed in the bone fragments 31, 32 (figure 1), for example, two rods in each of the bone fragments, the bottom nuts 16 (figures 4, 5) are to be screwed into the rear ends of the rods 15 and sliders 6 are adjusted inside them after having first installed (or rotated) the spacer sleeves 8 with nuts 14 in each of the cursors 6. Then the top nuts 17 are adjusted on each of the rods 15 after which frame 1 (figure 1) is placed parallel to the surface of the patient's body at a distance of 1.5 to 2 cm apart so that cursors 6 (figure 2) are arranged on an axis 33 of symmetry of frame 1 and the clamping screws 11 are inserted from the outside through the recesses 5 (figure 4.5) in the longitudinal wall 3, the spacer sleeve 8 and the recess 5 in the longitudinal wall 4, after which the nut 13 is adjusted on the rod 15. Then the nuts 13, 14 17 they are finally tightened to hold spacer sleeves 8 and rods 15 in place.

Whenever it is necessary to replace each of the rods, for example, in case rod 15 remains loose in bone fragment 31 or 32 (figure 1) and there is a need to replace rod 15 with one of a larger diameter, nuts 13 (figures 4, 5) are unscrewed, the clamping screw 11 is extracted, the nut 17 is turned and the cursor 6 is removed together with the spaced sleeve

15, / 70 33Θ

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-13ciadora 8. Then the rod 15 is rotated out of the bone fragment 31 or 32 (figure 1). a new rod 15 is rotated inside it and fixed in position on the frame 1 in reverse order.

To remove the frame 1 the nuts 13 (figures 4, 5) are unscrewed and the clamping screws 12 are removed after which the frame (figure 1) is taken out freely. Once the nuts 17 (figures 4, 5) have been turned out of the slides 6, together with the spacer sleeves, the meamas are removed.

The construction of the device described above provides extensive functional capabilities to it, as well as the possibility of replacing some individual repositioning units (figure 1), without removing the frame 1, but with the bone fragments 31, 32 remaining fixed in position with the assistance from the remaining 2 repositioning units.

On the contrary, the prototype of the device mentioned above can be installed by a single operator, which is important during surgery.

In order to provide the highest facility in the installation of the rods 15 in the frame 1, due to the provision of an external access to the fixing elements (nuts), unlike the case with the prototype in which a key should be manipulated in a restricted space between the frame and the patient's body, as well as to shorten the installation time of the device, the slide 6 (figure 9) is provided with a sliding nut 34 whose body 35 (figure 10) is mounted with a possibility of free rotation in the longitudinal hole of the slide 6. The slide nut 34 has a nut provided with a female thread 37. The body 35 of the slide nut 34 is expanded at one end and locked against its detachment from the longitudinal hole of the slide 6 by a stop ring 38. The rod 15 (figure 11) is rotated inside the body 35 and locked with a nut 39 (figure 12) in it, the operation of the apparatus being possible without the use of nut 39.

To increase the functional capabilities of the device to re70 338

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-14 positioning of the bone fragments along inclined directions in the transverse planes of the frame (figure 1) the sliding nut 34 (figure 9) is adjusted on the slide with a possibility of angular displacement in the transversal plane of the frame 1 (figure 1). For this purpose, a support is provided on the slide 6 (figure 10) with a possibility of rotation in a transverse plane and fixation by means of a nut 41. The sliding nut 34 is installed in the support 40 with a possibility of free rotation. The locking of the sliding nut 34 and the adjustment of the rod 15 (figures 11, 12) therein are carried out in a manner similar to that described above.

The installation of the sliding nut 34 with a possibility of angular displacement in a transverse plane simplifies the process of installing the rods 15 while the requirement of parallelism of the rods 15 in the bone fragments is no longer necessary. In addition, the reliable fixation of the rods 15 in the frame 1 (figure 1) is ensured whatever their orientations in relation to the frame 1 and the installation time of the device is shortened.

The proposed osteosynthesis device is equipped with at least one immersion fixation unit 42 (figure 13). The provision of unit 42 is essential for the emergency fixation of bone fragments 31, 32 in field conditions and for the additional transport of the patient to the hospital.

Each of the fixing units 42 comprises two spacer sleeves 8 movable longitudinally (figure 14), the clamping screw 12 being passed through the hole 11 of each of said sleeves and through the recesses 5 in the longitudinal walls 3, 4, and being the slide 6 mounted on each of said sleeves with a possibility of rotation in relation to said sleeve. The slide 6 is provided with a collar clamp 43, consisting of a collar 44 and a conical union nut 45. The collar clamp 43 tightens a smooth rod 46.

In each of the emergency fixing units 42 (figure

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-1513) the smooth rods 46 are angled towards each other at an angle of 30 to 60q in a longitudinal plane of the frame 1. Figure 13 shows the construction of the apparatus that incorporates two emergency fixing units 42 and two repositioning units 2 Each of the emergency fixation units 42 establishes, together with part of the frame 1, a rigid truncated triangle that provides reliable fixation of the bone fragment 31 or 32. An angle between the smooth rods 46 below 30 ° adversely affects the rigidity of fixation of the bone fragment, while said angle exceeding 60 ° involves a longer length of the frame 1. Each of the bone fragments 31, 32 must be fixed in place with at least one emergency fixation unit 42 provided with two smooth rods 46. To increase the operating capabilities of the device to fix these bone fragments, in which the support holes have been drilled differently different angles in relation to a longitudinal plane of the frame 1, which is dictated by the configuration of the bone fragments and by the drilling conditions in emergency situations, another embodiment of the construction of the emergency fixation unit was developed according to which a support 47 is fitted into the hole in the slide 6 (figure 15) with a possibility of rotation in a transverse plane and fixing by means of the nut 41. The collar 44 is mounted on the support 47, in which the conical union nut 45 is threaded. the support portion of the smooth rod 46 is locked in the collar clamp 43. The provision of the support 47 makes it possible to fix bone fragments in cases where the support holes have to be drilled in them, with different angles in relation to a longitudinal plane, what has proved in practice almost always to be the case.

The device equipped with the emergency fixing units 42 (figure 13) is installed as follows.

The support holes are drilled in the bone fragments 31, 32 to install all the rods 15, 46. In this case, the holes for installing the smooth rods 46 must be drilled with the necessary clearance for the required angle (30 to 60 °) while that the holes adapted to receive the rods 15 must be

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-16 scoring to a required diameter for your threads. Then the smooth rods 46 are inserted in their respective support holes and the rods 15 are screwed with their own taper portion 18 (figure 6). Then the slides 6 previously assembled together with the collar fasteners 43 (or with the slides 6 supporting the supports 47 (figure 15), with the collar fasteners 43) and with the spacer sleeves 8 (figure 12) and the nuts 14 the slides 6 (previously assembled together) supporting the support 40 with the sliding nut 34 are screwed onto the smooth rods (figure 14) in the manner described above. (figures 12, 14) have been adjusted in position with respect to the longitudinal plane of the frame 1 (figure 13) and the slides 6 (figure 11) have been adjusted in height on the rods 15 in relation to the surface of the patient's limb, the frame 1 (figure 13) is installed and the clamping screws 12 (figure 16) are passed through the longitudinal recesses 5 (figure 15) in the frame 1 and through the holes 11 (figure 15) in the spacer sleeves 8, after which the nuts13 (figure 16) are fitted in place on all emergency units 42. Then slides 6 are brought together and manually in each of the emergency fixing units 42 along recesses 5 (figure 13) of frame 1 of in order to support the excess of gaps between the support holes in the bone fragment 31 or 32 and the working portion of the smooth rods 46. Since the tension force of 2 to 3Kg force is sufficient to support the said excess of gaps and flatten the contact points of the bone fragments 31 or 32, the nuts 13 (figure 16) on the clamping screws are tightened and the emergency fixing units 42 are fixed in position on the frame 1, tightening the conical nuts 45 (figure 1) , nuts 14 (figure 14) and nuts 41 (figure 15). After which the repositioning units are fixed in position on frame 1 (figure 13) as described above.

To prevent widening of the recesses 5 in the frame 1, C-washers are used, which prevent flexing of the longitudinal components70 338

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-17 ends of each longitudinal wall 3, 4 (figure 16) of the frame 1 when tightening the clamping screws 12 and during the transport of the device by the patient.

The release of the bone fragments 31, 32 (figure 13) and the removal of the apparatus are carried out in reverse order, that is, first the nuts 13 (figure 16) are unscrewed, the clamping screws 12 are removed, the frame 1 is removed, the conical nuts 45 (figure 14) are released and the smooth rods 46 are removed, the rods 15 (figure 1) are rotated out of the support holes and the repositioning units 2 (figure 3) are removed.

The proposed device is equipped with a fixation unit 49 for the bone fragment of the femoral neck (figure 1). The aforementioned unit comprises a body 50 having two parallel holes, a screw 51 being passed through said holes and through the recesses 5 in the longitudinal walls 3, 4 (figure 18) of the frame 1 and being fixed by a nut 52. The body 50 has a central hole 53 (figure 17) whose axis makes an angle of about 120 to 130 ° with respect to the plane of the frame 1. A sliding nut 54 is mounted in the central hole 53 with a possibility of free rotation, one being body 55 of nut 54 expanded at one end and secured against loosening in central hole 53 by means of a stop ring 56. body 55 has a threaded hole 57 into which rod 15 is rotated.

apparatus provided with the fixation device 49 of the bone fragment of the femoral neck, is installed as follows. Support holes are drilled in the bone fragments 58 and 59 after which the repositioning units 2 (figure 1) are installed in the bone fragment 50 in a similar manner to that described above. Then the rod 15 is rotated inside the bone fragment 58 (figure 17), and the sliding nut 54 is adjusted in the rod 15, said nut being fitted in the body 50 of the unit 49. Then the spacer sleeves 8 and the longitudinal holes in the body 50 (figure 17) are brought to the same plane by adjusting the portion

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-18 of the slides 6 (figure 4) on the spacer sleeves 8 and the body 50 (figure 17) on the rod 15, after which the frame 1 is installed in position, the fastening screws 12 (figure 4) and 51 (figure 18) they are adjusted through the recesses 5 (figure 4) in the walls 3, 4 in the spacer sleeves 8 and therefore in the body 50 (figure 1) of the unit 49. Then the nuts 13 (figure 4) and consequently the nuts 52 (figure 1) are tight. The body 50 is blocked against transverse displacement by a nut 60.

The prediction of Unit 49 increases the functional capabilities of the present osteosynthesis apparatus, due to the possibility of fixing and repositioning the bone fragments of the femoral neck and the fixation of the bone fragment with a single rod arranged in cantilever in relation to the frame.

To add rigidity to the frame 1, in the longitudinal plane, to simplify the construction of the apparatus in all the embodiments described above, at least the bridge 61 is provided in the longitudinal recess 5 (figure 19) of each of the longitudinal walls 3, 4, said bridge the longitudinal recess 5 is divided into two portions. Figure 20 represents the longitudinal recess 5 with two bridges 61. The provision of the two bridges 61 makes it possible to dispense with the fixing elements for the spacer sleeves 8 (figure 12), such as C 48 washers as well as adding rigidity to the bone fragments and accelerating installation of the device.

The proposed osteosynthesis apparatus is provided with a device 62 (figure 21) for an adjustable longitudinal displacement of the bone fragments 31, 32. The device 62 comprises a U-piece 62 (figure 22) provided with longitudinal recesses 64 (figure 21) in its side walls 65, said recesses being adapted to accommodate and fix clamping screws 66 (figure 22) of at least two repositioning units 2, while the heads of the clamping screws 12 have threaded bosses 67. One end 68 of the U-piece 63 supports a sliding nut 69 and reinforcement ribs 70, said nuts and said ribs being held rigidly in the U-piece 63. The provision 338

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-19 active 62 is provided with means 71 (figure 71) to provide longitudinal movement to the U-piece 63 comprising said means a detachable fastener 72 and an adjusting screw 73, which is mounted on the sliding nut 69 and is provided with a button 74 and a thrust washer 75 (figure 23), said washer rotatably mounted on the end of the adjustment screw 73 by means of screw 76 blocked with a pin 77. The adjustment screw 73 has a flat part 78 (figure 24) arranged along the length of its shank, a metric scale 79 (figure 23) being provided on the flat part 78. The fastener 72 interconnects an end 80 of the frame 1 and the end of the adjusting screw 73 has an E-shaped cross section and it has a groove 81 in one of its outer walls 82. When the detachable clamp 72 is adjusted outside the frame 1, its end 80 engages in a groove 83, while another groove 84 accommodates washer thrust 75, and the groove 81 accommodates the end of the adjusting screw 73. The width of the groove 81 (figure 24) exceeds the diameter of the adjusting screw 73 but is smaller than the diameter of the thrust washer 75, which prevents loosening of the thrust washer 75 when the adjusting screw 73 is being turned and the U-piece 63 (figure 22) moves longitudinally. A U-piece 63 is thus brought in from the end 80 of the frame 1 so that the recesses 64 (figure 21) of the walls 65 slide over the ends of the clamping screws 66 (figure 22) and the ends of the threaded cups 67 of the screw heads. The U-piece 63 is fixed to the clamping screws 66 (figure 25) by means of free locking nuts 85 washers C 86 and additional outer nuts 87.

apparatus with the construction described above is installed as follows.

Before the surgery, the slides 6 and the nut 14 must be rotated for the spacer sleeves 8, so that the slides assume an average position in the spacer sleeves 8. Once the rods 15 have been fixed in the bone fragments 31, 32 during surgery, a nut 16 (figure 25), a slide 6 supporting the

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-20 spacer sleeve 8, and a nut 17 are fitted to the rear portions of the rods 15. Then the frame 1 (figure 21) is spaced 1 or 2 cm away from the patient's body so that the rods 15 are arranged on the axis 33 (figure 22 ) of the frame 1, the transverse position of the slides 6 is adjusted by turning the spacer sleeves 8, and the latter sleeves are locked in place by means of the tightening screws 12 and 76 adjusted from the outside. Once the frame 1 has been preliminarily installed, the nuts 13, 14 and 16 (figure 25), 17, 85 are tightened, thus ensuring the rigid interconnection of the rods 15 and the frame 1 (figure 22).

In order to provide a longitudinal displacement of the bone fragments 31, 32 (figure 21) in one another, the U-piece 63 is adjusted in the frame 1 from its end 80 (figure 22) in such a way that the ends of the screws tightening 66 and the threaded bosses 67 of the screw heads must engage in the recesses 64 (figure 21) on the walls 65 of said U-piece 63. Then the additional nuts 86 (figure 25) are adjusted on the tightening screws 66, after which the end of the adjusting screw 73 (figure 23) is brought to the frame end 80, and the detachable clamp 72 is adjusted from the outside at said end 80 and the thrust washer 75, the excess clearance is removed through the rotation of the adjustment screw 73 the lock nuts 85 (figure 25) are loosened at the ends of the clamping screws 66 and said nuts 85 are tightened on the walls 65 of the U-piece 63 (figure 22). In this way, the rigid support of the other bone fragment 32 (figure 21) in the U-piece 63 is obtained, as well as providing a free displacement of the spacer sleeves 8 (figure 25) along the recesses 64 (figure 21). Then the bone fragments 31, 32 are displaced longitudinally by rotating the adjustment screws 73 in both directions and the amount of relative displacement of the bone fragments 31, 32 is read on the metric scale 79 (figure 23) on the adjustment screw 73, serving the end of the sliding nut 69 (figure 23) or the end 68 of the U-piece 63 as a flduclal point, since the difference between the readings taken before and after the displacement

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0802/2 Ρ. 117205 — Μ-68

-21 are essentially equal to the amount of displacement. Once the pre-established displacement of the bone fragments 31, 32 (figure 21) has been performed, the nuts 85 (figure 22) are tightened on the frame 1, thus freeing the walls 65 of the U-shaped pieces 63 and fixing the bone fragments 31, 32 (figure 21) in a new position on the frame 1. Then the clamp 72 (figure 22) and the U-piece 63 are removed. All of the procedures described above can be performed by a single operator.

Thus, device 62 (figure 21) for adjustable longitudinal displacement of bone fragments 31, 32 is installed in frame 1 only in 3 to 5 minutes for simultaneous or multi-scaled longitudinal displacement of said bone fragments, while the rest of the operation time of frame 1 is free of said device 62. This allows the same device 62 to be used in a number of devices for extrafocal osteosynthesis, not imposing additional weight on the device during treatment and not offering inconveniences for the patient.

338

Claims (11)

CLAIMS la ^- Osteosynthesis apparatus, comprising an oblong frame having each of its two longitudinal walls a longitudinal recess and at least four repositioning units, each including a cursor equipped with two crossed holes, that is, a longitudinal and a transversal, a support element installed in the transversal hole of the cursor with a possibility of longitudinal displacement and fixation, in the longitudinal recesses of the longitudinal walls of the frame, and a rod having its own taper and a threaded portion, said rod being fitted in the longitudinal hole. cursor with a possibility of axial displacement and fixation, characterized in that each of the support elements is shaped as a spacer sleeve, having a male thread and slots for a key, said slots located in the vicinity of the sleeve ends adapted to interact in the interior surface of the later walls frames, while a clamping screw passes through the hole in a spacer sleeve and through the longitudinal recesses of the longitudinal frame walls. 2a - Apparatus according to vindication king 1, characterized in that the longitudinal frame walls are flattened. 3a - Apparatus according to claim 1, characterized in that the transverse cursor hole is threaded and the spacer sleeve is rotated in said hole. 4a - Apparatus according to claim 1, characterized in that the slider is provided with a sliding nut whose body is installed with a possibility of free rotation in the longitudinal hole of the slider, while the rod is rotated in its threaded portion inside the sliding nut. . 5 - Apparatus according to claim 4, characterized in that the sliding nut is installed on the slider with a possibility of angular displacement in the transverse plane of the frame. 6a - Apparatus according to claim 1, characterized 70 338 0802/2 Ρ.117205-Μ-68 -23 because a femur neck bone fixation unit is provided therein, comprising a body provided with two parallel and complementary transverse holes, and a clamping screw which is passed through each of the said complementary holes and through the longitudinal recesses in the longitudinal frame walls, with a central hole, in which the body of the sliding nut is adjusted with a possibility of free rotation, the axis of said central hole being arranged at an angle of 120 to 130 degrees in relation to the plane of the frame, and a rod rotated inside the sliding nut with its threaded portion. Apparatus according to claims 4 and 6, characterized in that a cylindrical recess is provided in the portion of the taper rod proper near the rod end, said recess having a length equal to 0.5 or 0.8 of the length a portion of the proper taper rod, a depth equal to 0.2 or 0.6 of the thread depth. 8a - Apparatus according to claim 1, characterized in that at least one emergency fixing unit is provided, comprising two spacer sleeves installed with a possibility of longitudinal displacement and fixation and fitted with a clamping screw passed through the hole. each of said spacer sleeves and through the longitudinal recess in the longitudinal frame walls, while each of said spacer sleeves supports a slider with a collar clamp that supports a fully staggered rod, said slider being able to rotate in relation to the spacer sleeve. Apparatus according to claim 1, characterized in that the longitudinal recess in each of the longitudinal frame walls has at least one bridge that subdivides the longitudinal recesses in portions. Apparatus according to claim 1, characterized in that a device is provided for an adjustable longitudinal displacement of the bone fragment, said device comprising a U-shaped part, having longitudinal grooves in its side walls. 70 338 0802/2 Ρ.117205 — Μ-68 -24, said slots being adapted to accommodate and secure the clamping screws of at least two repositioning units, and means to provide longitudinal movement to said U-piece, while the heads of said clamping screws are provided with threaded bosses . Apparatus according to claim 10, characterized in that the means for imparting longitudinal movement to the U-piece comprise a detachable clamp adapted to be installed in the frame end wall and an adjustment screw, which is fitted in a threaded hole provided in the medium portion in the U-piece and is adapted to interact, through its end, with the detachable clamp.