DE2359644A1 - Osteosynthesis nail with guide wire lance - has spreader body at end of constantly widening cross section - Google Patents

Abstract

Osteosynthesis appts. consists of a hollow marrow nail and a wire lance to guide it. The nail has at its end at least 3 longitudinal slots distributed over the periphery. The guide lance has a spreader body at its end, with the end remote from the lance end smaller than the cross section of the nail cavity and constantly widening from this end cross section on at least part of its length to a cross section which is larger than that of the nail cavity. Preferably the nail is a Kuntscher's nail, with a longitudinally slot over its whole length, and with 2 additional longitudinal slots in the end cross section, set at 120 deg. to the through slot. The nail can be used when the point of fracture is near the joint.

Description

November 28, 1973

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Dr. med- Armin Fenselau Haibach

"Device for osteosynthesis"

The invention relates to a device for osteosynthesis, consisting from a hollow intramedullary nail and a wire skewer for Guidance of the nail. -

In the field of boil surgery, it is known in the case nail a fracture of a long long bone.

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The bone nailing is done after the fracture has been repositioned very precisely by surgically hammering in one stainless steel nail into the medullary canal under X-ray control. A well-known nail that has established itself in bone surgery is the so-called Küntscher nail, whose Cross-section essentially has the shape of a clover leaf and with one extending over the entire length of the nail Longitudinal slot is provided. Such a bone nailing in which the nails are precisely adapted to the medullary cavity until the fracture heals are left in the bone has the advantage that the fracture ends are fixed in their position by internal splinting being held. Another advantage is that the fracture site does not need to be opened surgically, so that there is little or no risk of infection. The patient does not need a plaster cast and can already after a short period of lying in bed stand up. Follow-up treatments are usually not necessary because there are no muscle atrophies or mobility restrictions appear.

The well-known principle of bone nailing is only suitable for fractures that are far enough away from the joint so that the nail used for the internal splint fixes the bone on both sides of the fracture site. Is the Break point very close to a joint, where the cancellous bone is already far back and gives way to a larger bone cavity,

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ORIGINAL IWSPECTED

so the well-known principle of bone nailing is no longer applicable reversible. In such a case · when performing a Osteosynthesis, other methods can be used, such as attaching an adapted plate outside the bone with surgical opening of the fracture site from the outside.

The invention is based on the task of providing a device

themselves

create theV, while retaining that which occurs during intramedullary nailing Advantages can also be used when the fracture ■ is close to the joint. '. . ■

The invention is based on the known from a hollow Intramedullary nail and a guide wire and solves the problem set in that the intramedullary nail has at its end at least three longitudinal slots distributed over its circumference and that the guide wire is attached its end is provided with an expansion body, the end cross section of which, facing away from the end of the spit, is smaller than the cross section of the nail cavity and which extends from this end cross-section at least over a partial length continuously up to a cross-section expanded, ■ which is larger than the cross-section of the nail cavity is. "" · - - -

When using the device according to the invention, the with the spreader provided with the guide wire after hammering in the

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The nail is retracted a little relative to the nail, with the
Spreader penetrates at least partially into the cavity of the nail and at the end of the nail between the longitudinal slots
located lamellae bends outward, so that they lay firmly on the inner wall of the enlarged bone cavity and thus fix both ends of the fracture site in their position extremely stable. The handling of the device according to the invention is extremely simple and only requires the known instruments, such as those required for thigh or lower leg nailing with the addition of three known instruments which are used to loosen jammed guide pins during trochanter nailing.

A Küntscher nail with a longitudinal slot over the entire length is preferably used as the intramedullary nail.
which is provided in its end section with two additional longitudinal slots offset from the slot at angular distances of about 120 °. When the Küntscher nail is on
is known to have the shape of a three-leaf clover, the two additional longitudinal slots are expediently made in the constrictions of the clover. The longitudinal slots can be up to 12 cm long.

The nail end can have a bevel, the bevel expediently being at an angle of 40 to 60 °, preferably of about 45 °. The bevel points at
Use of the Küntscher nail, its cloverleaf-shaped one

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ORIGINAL INSPECTED

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Cross-section is slightly asymmetrical, the advantage on that the expansion body.-relative. "to the nail cavity better is centered. For this purpose, the bevel is preferably based on the nail side provided with the longitudinal slit and extends from there obliquely upwards to the nail head.

The expansion body preferably has the shape of a blunt Double cone, the bases of the truncated cones against each other issue. The one used to expand the end of the nail For example, a truncated cone has an opening angle in of the order of. 45 to “The other truncated cone is preferred provided with a larger opening angle. The ratio of the heights of the two truncated cones is about 1: 2, the truncated cone used to widen the nail being the higher. "-..-.-" - "::

The holder of the expansion body on the guide wire; can on done different ways. It is possible to use the expansion body from the beginning firmly to the end of the guide wire associate. However, this would mean that the guide wire are inserted into the bone together with the expansion body would have to. Since this leads to the introduction of the guide wire into the. Bone and the loosening of the spreader is made more difficult the expansion body is preferably formed and is separately

only pushed in after the guide wire has been inserted. Of the Wire skewer can. .-

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ORIGINAL INSPECTED J

for this purpose have a smooth surface and on his End to be provided with a slight thickening, while the expansion body has a through hole, which is on the wire skewer forms a sliding fit. The expansion body can then be placed on the smooth wire skewer, for example with the aid of a wire skewer overlapping plastic hose are inserted, until it comes to a stop at the thickening provided at the end of the skewer. Alternatively, the wire skewer can also be used over its entire length Length be provided with a thread and also have a stop at the end, while the expansion body one of the spit thread has adapted continuous threaded hole.

In a preferred embodiment, the wire skewer has a smooth surface and is raised at the end Provided thread, while the expansion body has a threaded hole adapted to the end thread, the inner diameter of which is larger than the diameter of the wire skewer. In this embodiment, the expansion body with the help of a Plastic tube after the insertion of the wire skewer are pushed onto this and can then by rotating the guide wire, the threads come into engagement with one another the guide wire are connected so that the expansion body is both advanced and together with the guide wire can be withdrawn. To facilitate the engagement of the threads, the end facing the end of the wire skewer can be used

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of the expansion body on an enlarged hole without thread. that is larger than the outer diameter of the spit thread. ■

To prevent the guide wire from the expansion body can be screwed out and this then falls into the bone cavity The end of the expansion body bore may be designed without a thread and have a diameter that is smaller than the outer diameter of the spit thread. -

The invention is illustrated in the drawing, for example and described in detail below with reference to the drawing. Show it: .

1 shows a preferred embodiment of the device, which is set in a femur

FIG. 2 shows the lower end of the wire skewer from FIG. 1, partially in section, with the expanding body screwed on,

FIG. 3 shows a section along the line III-III from FIG. through the lower end of a Küntscher nail with a cloverleaf cross-section, which is provided with two additional longitudinal slits, and

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FIG. 4 shows a section through the lower end of the nail along the line IV-IV from FIG. 3.

According to Fig. 1 of the drawing, in which the synthesis of a femur As illustrated in Fig. 2, the device for internal splinting of the bone consists of an intramedullary nail 4, a wire skewer 6 and an expanding body 8.

The nail 4 is a modified Küntscher nail, whose cross-section according to FIG. 3 has approximately the shape of a three-leaf clover and over its entire Length is provided with a longitudinal slot 10. The longitudinal slit 10 is located in a constriction of the clover leaf, the two bulges adjoining the longitudinal slot 10 12 and 14 have a slightly larger radius of curvature than the bulge opposite the longitudinal slot 10 16. In its end section, in the two remaining constrictions of the trefoil cross-section, there is a further longitudinal slot 18 and 2o are provided, which extend from the end of the nail and are up to 12 cm long. The lower end of the nail, which is drawn inwards a little to make it easier to fold is, has a bevel 22 which extends from the side of the longitudinal slot 10 at an angle of approximately extends obliquely upwards, i.e. that the bevel 22 runs from ventral cranial to dorsal caudal. The top end of the nail is not compared to the well-known Küntscher-Nagol

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have been modified and therefore need not be described further.

The wire spike 6 provided for guiding the intramedullary nail has just like the well-known wire skewers over its length smooth surface, but the wire skewer 6 is in contrast to the well-known wire skewers at the end with a raised one Thread 24 provided, which can be produced, for example, that the thread grooves with a corresponding Tool to be pressed in so that thread projections are over raise the diameter of the wire out. The remaining .Abschnitt of the wire skewer is designed in the same way as the well-known wire skewers. ,. - ■; "

The expansion body 8, like the nail 4 and the wire skewer 6, is made of stainless steel and has the shape of a double truncated cone, with the base surfaces of the truncated cones 26 and 28 resting against one another. The truncated cone 26, which is used to widen the nail end, has an opening angle of approximately 45 ° and is approximately twice as high as the opposite truncated cone 28, which has a more obtuse opening angle. Exactly in the cone axis of the two truncated cones and 28 runs a through hole 30, which is provided in its central portion 32 with a thread, which the. , End thread 24 of the wire skewer 6 is adapted and can be screwed onto this to achieve <? * -> = './cfe "// - ^^ tr .

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In the upper region of the truncated cone 26 serving to expand the nail end, the bore 30 has a tapered section 34., the diameter of which is greater than that of the smooth area of the wire skewer 6, but smaller than the outer diameter of the raised threads of the end portion 24 of the wire skewer, so that the lower end of the tapered bore section 34 serves as a stop for the threaded section 24. On the opposite At the end of the expansion body, the bore 30 has a widened section -36, the diameter of which is greater than is the outer diameter of the threaded section 24 of the wire skewer, "so that the expansion body easily hits the threaded section 24 of the wire skewer can be drawn up and the threaded halves can be easily brought into engagement with one another.

The mode of operation of the device will be based on the following a femur nailing are explained, the femur 2 according to FIG. 1 near the knee joint has a transverse fracture 38:

First of all, the upper end of the femur 2 is opened at a typical location and the medullary level is widened as usual. Then the skewer used for the expansion is exchanged for the wire skewer 6 provided with the distal end thread 24. In order not to cause any dislocation at the break point when changing the two skewers, a guide sleeve is used Teflon tube commonly used to rinse the medullary cavity.

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The expansion body 8, the largest diameter of which is after Enlargement of the medullary cavity '(minus 0.5 mm) is now with its short truncated cone distally onto the wire skewer 6 put on and glides, possibly pushing the ■■ -. . Teflon tube, in the depth of the 'medullary cavity. The enlarged distal Bore section 36 of the expansion body enables safe guidance of the expansion body on the thread. By rotating the Wire skewer counterclockwise with the help of a Jacob's lining creates a firm connection between wire skewer 6 and Spreader 8. The risk of the thread coming out proximally ■ the bolt is unscrewed, does not exist because the end thread: 24 of the wire skewer 6 at the lower end of the tapered bore section 34 strikes.

The choice of the diameter of the marrow hail used is directed ^ in the usual way after the widening of the medullary cavity (largest Width minus 1 mm). The choice of nail length depends on the length of the wire spike in the medullary cavity (minus Length of the expansion body). ',. :

The nail is typically pushed over the wire skewer and driven into the medullary cavity with short, powerful blows. With careful selection of the nail length, the nail tip has reached the upper edge of the spreader when the entire Nail length has been driven into the medullary cavity.

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Then there will be a whipper, a skewer extractor as well Jacob's lining placed on the guide spike, as it jammed in the Küntscher trochanter nailing to remove Guide pins apply. Carefully turning the extractor pulls the wire skewer out of the Bone. The screwed-on expansion body is drawn into the nail 4 with its proximal truncated cone 26. The on The bevel 22 provided at the lower end of the nail forces the expansion body to be centered relative to the center of the nail between the three slats formed by the longitudinal slots. The nail is spread under image intensifier control up to to apply the lamellae to the corticalis.

The wire skewer is used in preparation for a later nail extraction rotated clockwise with the help of the Jacob's chuck, so that the end thread 24 from the expansion body in a distal direction unscrews. The wire skewer is then guided down to the floor of the widened medullary cavity, while the excessively long proximal The guide wire portion is bent over at the point where the nail is struck and cut off with a wire cutter.

In this state, the expansion body 8 is held in place by the lamellae of the lower end of the nail, which are expanded under tension, while the lamellae lie against the inner walls of the medullary cavity and ensure stable splinting of the fracture site.

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If after a certain tent: the fracture site collapses ■ is growing, the nail is removed. The removal is done by first looking for the nail head and pulling the wire skewer 6 out of the cavity of the nail 4, to the end thread 24 in the enlarged bore section 36 of the expansion body 8 is located. Then the wire skewer is rotated so that the end portion is in the thread 32 of the expansion body 8 screwed in. After a firm hold between the wire spike 6 and the expansion body 8 is achieved, "the Spreader body by careful blows on the nail protruding end of the wire skewer pushed down, - with the Wire skewer must be carefully guided with flat nose pliers. Then the nail is pulled out of the with the help of a ratchet hook Bones are removed and finally the wire skewer is put together pulled out of the medullary cavity with the screwed-on spreader and then closed the wound.

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Claims (1)

- 14 claims Device for osteosynthesis, consisting of a hollow intramedullary nail and a wire spike for guiding the nail, characterized in that the intramedullary nail (4) has at its end at least three longitudinal slots (1o, 18, 20) distributed over its circumference and that the guide spit (6) is provided at its end with an expansion body (8), the end of which is remote from the spit end End cross-section is smaller than the cross-section of the nail cavity and which differs from this end cross-section from at least a partial length continuously expanded to a cross-section that is larger than the cross-section of the Nail cavity is. - 2. Device according to claim 1, characterized in that that the intramedullary nail (4) is provided with a longitudinal slot (10) over its entire length Küntscher-Nagel is, in its end cross-section with two additional ones, at angular distances of about 120 ° to the Slot (10) offset longitudinal slots (18, 20) is provided. 3. Device according to claim 2, characterized in that that the Küntscher nail (4) in a manner known per se is approximately the shape of a three-leaved clover S09831 / Ö322 . "■ ■ - ■■■■■. ': .2353644 sheet and that the two additional longitudinal '-, slots (18, 20) in the constrictions of the clover leaf are provided »-.". '■.; " Λ. Device according to one of Claims 1 to 3, d a d u r c h ge k e η η ζ. ei oh η e t that the Longitudinal slots - (18 ", 20) up to 12 cm long. 5. Device according to one of claims 1 to 4, as through ge k e η η ζ e i c h η e t that that The end of the nail has a bevel (22). : 6. Apparatus according to claim 5, dad u r c h g e-k e η η draws η et that the bevel (22) at the point of the nail at an angle of 40 to 60 °, preferably of about 45 °. ' 7. Apparatus according to claim 3 and 5, since d u.r c h gek en η ζ eich η et that the bevel (22) starts from the nail side provided with the longitudinal slot (10). · """· .- ■ -'-- - 8. The device according to claim 1, d ä d u r-c h ge k e η η ζ e i c h η e t that the expansion body (8) 'the Has the shape of a truncated double cone, the 509831/0322 \. . . . ■■ "■■ .- ■ - 16 ~ Base surfaces of the truncated cones (26, 28) against one another
issue. 9. Apparatus according to claim 8, characterized in that that the truncated cone (26) used to widen the nail end has an opening angle of has about 45 °. 10. The device according to claim 9, characterized in that the expansion of the Nail end serving truncated cone (26) has an opening angle which is smaller than that of the opposite Truncated cone (28). 11. Apparatus according to claim 9 or 10, characterized
characterized in that the truncated cone (26) serving to expand the nail end is approximately twice as high as the truncated cone (28) facing away. 12. The device according to claim 1, characterized in that the wire skewer (6) has a has a smooth surface and is provided at its end with a thickening (24) and that the expansion body (8) has a through hole (30) which forms a sliding fit on the wire skewer (6). - 17 - 609831/0322 ' 13. The apparatus of claim 1, d a you r · c h characterized in that the wire skewer a has a smooth surface and at the end with a raised Thread (24) is provided and that the expansion body (8) has a threaded bore (30) adapted to the end thread, the inner diameter of which is greater than the diameter of the wire spit (6). 14. The device according to claim 1-3 »characterized in that the end of the wire · * The end of the expansion body (8) facing the skewer (6) has a widened bore (36) without a thread. greater is than the outside diameter of the end of the. skewer provided raised thread "(24). ' 15. The apparatus of claim 14, characterized in that g e k e η η ζ ei without t that the extended End section (34) facing away from the bore section (36) of the expansion body bore (30) is designed without a thread and has a diameter that is smaller than the, Outside diameter of the spit thread (24). . ..-- .; ..... 16. The apparatus of claim 1, d a d u r.c h ... characterized, that the wire skewer over his entire length is threaded and one at the end - 13 - 5U9Ö31 / Ö322 Has stop and that the expansion body has a continuous threaded hole adapted to the skewer thread) 509831/0322