EP3193756A1

EP3193756A1 - Osteosynthesis aid for the care of subtrochanteric fractures and/or pertrochanteric fractures and/or femoral neck fractures

Info

Publication number: EP3193756A1
Application number: EP15763945.1A
Authority: EP
Inventors: Klaus-Jürgen MAIER; Ulrich Finger; Mathilde FAUCON; Christian Günsche
Original assignee: Koenigsee Implantate GmbH
Current assignee: Koenigsee Implantate GmbH
Priority date: 2014-09-19
Filing date: 2015-09-18
Publication date: 2017-07-26
Also published as: WO2016042148A1; DE102014113556A1

Abstract

The invention relates to an osteosynthesis aid (10) for the intramedullary supply of subtrochanteric fractures and/or pertrochanteric fractures and/or femoral neck fractures, comprising a femur nail (20) that can be inserted into the medullary cavity of a femur, a distal portion (21) and a proximal portion (22) having a through-opening (25) which extends obliquely with respect to the longitudinal axis (L) of the femur nail (20) and has a lateral inlet end (26), a medial outlet end (27) and a passage wall (28), wherein a load carrier (30) can be inserted into the through-opening (25). According to the invention, the lateral inlet end (26) and/or the medial outlet end (27) comprise over the entire circumference a chamfer (40) such that a chamfer surface (41) oriented towards the passage wall (28) is formed.

Description

Osteosynthesis aids for the treatment of subtrochanteric fractures and / or pertrochanteric fractures and / or femoral neck fractures

description

The invention relates to an osteosynthesis aid for intramedullary

Treatment of subtrochanteric fractures and / or pertrochanteric fractures and / or femoral neck fractures _. , comprising a femoral nail insertable into the medullary cavity of a femur, having a distal portion and a proximal portion having a passage opening extending obliquely to the longitudinal axis of the femur, having a lateral entry end, a medial exit end and a passage wall, wherein a force carrier is insertable into the passage opening The invention further relates to a force carrier for an osteosynthesis aid, according to the preamble of claim 7.

Proximal femoral nail for the osteosynthesis of femoral neck fractures and petrochanteric and subtrochanteric fractures are used in various embodiments and have been in clinical use for several decades. The distal portion of such femoral nail is angled for adaptation to the medullary cavity to the proximal portion, preferably by 3 to 7 degrees.

Optionally, such nails in the proximal portion of the nail may have a bore or aperture for receiving a force carrier, wherein the force carrier is driven by the femoral neck in the femoral head. Such a force carrier is preferably rotationally stable anchoring in the femoral head, while rotation stability between the power carrier and the rod should be guaranteed.

The known from clinical use femoral nails are usually constructed so that the power carrier can slide in its axial direction through the nail, so that a sintering or approach of the fragments of a femoral neck fracture is made possible. By sintering the fracture zone, the healing process should be improved. Infinite dynamization of the primary restoration can, in many cases, severely sinter the fracture zone of the bone during the healing process, shortening the healing bone and adversely altering the anatomy and biomechanics of the femur. Therefore, it is known from the prior art that the

Dynamization can be approximately completely canceled.

In most healing processes, however, this is beneficial only at the beginning of the fracture healing, so that blocking the dynamization by a second

Operation must be lifted. A lack of dynamization could lead to the absence of healing and a nail break.

Another important factor is the stabilization of the lateral wall, the so-called trochanter major, as well as peri-implant fractures such. B. the outbreak of the lateral wall, to muscle insufficiencies, clinical

Discomfort and healing disorders.

Consequently, the disadvantage of known femoral nails is that they hitherto only offer the possibility of either allowing an in principle unlimited dynamization or of completely canceling out the dynamization. An unlimited dynamization has the disadvantage of a strong shortening of the bone in the healing process, which in turn can lead to permanent impairment and pain in the patient.

With a complete blocking of the dynamization this can become a

Failure of bone healing and lead to a pseudoarthrosis, if such a Heiiungsproblematik is not recognized in time. The insertion of so-called femoral nails takes place via a hole at the proximal tip of the greater trochanter. Here it is necessary that the Muskelansitze located there be damaged or irritated as little as possible. Another requirement of surgeons is that the proximal

Nail diameter should be as small as possible, which at the same time must have a high load stability.

Based on the above, it is therefore an object of the invention to describe a further developed osteosynthesis aids, wherein a

Associated femoral nails on the one hand allows a dynamization and at the same time makes it possible to limit the dynamization when required, without this must be completely removed. Due to a limited dynamization bone healing should be promoted without the risk of excessive shortening of the bone.

From the foregoing, another object is to protect the lateral wall (greater trochanter).

A force carrier of an osteosynthesis aid should, according to a further object of the present invention, be designed to be load-stable in the bone and to prevent a rotation of the bone fragment. Loading stability in this context means that the force carrier is both mechanically stable enough to accommodate the cyclic loads, and is anchored so stable in the bone that it does not intersect under load, either perpendicular to its axis through the bone, or in the axial direction penetrates the bone.

A further object of the invention is to make the connection point of the force carrier with a nail of an osteosynthesis aid as stable as possible under static and dynamic load even with the smallest possible proximal Femurnageldurchmesser.

The solution of the task is done by an osteosynthesis tool for

intramedullary treatment of subtrochanteric fractures and / or pertrochanteric fractures and / or femoral neck fractures comprising a femoral nail insertable into the medullary cavity of a femur having a distal portion and a femoral nasal prone Proximal section, which has an obliquely to the longitudinal axis of the femoral nail extending through hole with a lateral inlet end, a medial Austrittsen.de and a passage wall, wherein in the

Through opening a force carrier can be used, according to claim i or by a force carrier according to claim 7. The subclaims include at least expedient refinements and developments.

It is therefore assumed that an osteosynthesis aid for the intramedullary treatment of subtrochanteric fractures and / or pertrochanteric fractures and / or femoral neck fractures, wherein a through-opening has a lateral inlet end and a medial outlet end.

According to the invention, the edges at the lateral entry end and / or at the medial exit end are provided with a chamfer, such that one for

Through wall oriented chamfer surface is formed. The edges at the lateral inlet end and / or at the medial outlet end therefore preferably have a chamfer in their entirety. The edges at the lateral entry end and / or at the medial exit end may depend on the cross section of the

Entrance end to a full edge, z. B. in circular and / or

Ellipse shape and / or oval shape act. Furthermore, it is conceivable that the edge is formed on the lateral entry end and / or on the medial exit end of a plurality of edge portions. This is conceivable, for example, if the lateral inlet end and / or the medial outlet end has a rectangular, square or polygonal cross section. The edge or the edges at the lateral inlet end and / or at the medial outlet end are therefore chamfered or curved slightly inward or outward. A chamfer is thus a chamfered or slightly inwardly or outwardly arched surface created at the edge of the lateral entrance end and / or the medial exit end.

The chamfer can have a depth of 0.05 mm - 5.0 mm, in particular 0.075 - 4.0 mm, in particular 0.1 mm - 3.0 mm, starting from the surface of the femoral nail.

During physiological loading of a femoral nail, the greatest stresses, namely tensile stresses, occur on the lateral side of the femoral nail, in particular at the lateral entry end of the passage opening of the femoral nail. By so-called FEM analyzes can be visualized that the design or the design of the circumferential edge of the lateral entrance end of the

Through hole essential influence on the stress distribution in the

Femurnage! Has. If the outer surface of the proximal part or section of the nail and the passage wall of the force carrier form a tapered edge, occur in the region of the cutting edge voltage spikes, which lead to rapid cracking and crack propagation under cyclic loading.

In addition to the risk of cracking due to tensile stresses on the lateral

There is also the risk of cracking due to compressive stresses at the medial exit end of the nail, especially if local

Voltage peaks the yield strength of the material is exceeded. A, in particular fully trained, chamfer, which is designed such that a passage wall facing towards chamfer surface is formed, causes a better stress distribution in the nail. Because of a better

Stress distribution in the nail can reduce the risk of cracking.

A substantial improvement in the stability of the femoral nail is achieved in that the peripheral edge of the lateral entry end and / or the medial exit end is provided with a chamfer or has a chamfer, wherein the nail cross section is not significantly weakened in the region of the passage of the force carrier. The chamfer surface and the passage wall of the through hole include an edge angle which is preferably> 90 degrees.

Preferably, the edge angle at the lateral inlet end and / or at the medial outlet end has an approximately equal value. As approximately the same value is understood in this context, that in connection with the chamfer surface and the passage wall sections individually formed edge angle only the range of a few degrees

differ from each other. The deviation of the values of the individual edge angles are preferably <10 degrees, in particular <7 degrees, in particular <5 degrees, in particular <2 degrees, in particular <0.5 degrees. The lateral inlet end and / or the medial outlet end preferably has a slot-shaped cross section. The lateral entry end and / or the medial exit end preferably has a cranial and caudal rounding. Between the cranial and caudal fillets, so between the ends of the slot-shaped cross-sections connecting webs are preferably formed. The fully formed bevel is preferably formed both in the region of the cranial and caudal rounding and in the region of the webs. These connecting webs are the starting point for crack formation and failure under dynamic load in femoral nails of the prior art.

The chamfer surface at the lateral entry end and / or at the medial exit end may be delimited by a first chamfer end region adjoining the passage wall, in particular full circumference, and a second chamfer end region adjoining the outer surface of the femur nail, in particular full circumference.

In a preferred embodiment, the first bevel end region and / or the second bevel end region is rounded.

The first bevel end region may be rounded in such a way that the

Through wall and the chamfer surface include an angle having a value greater than 90 degrees. Additionally or alternatively, the second

Beendendbereich be rounded so that the chamfer surface and the outer surface of the femur nail include an angle having a value greater than 90 degrees.

Preferably, the first bevel end region and / or the second

Chamfer area fully an approximately equal value. As approximately the same value is understood in this context, that in the

Relation with the chamfer surface and the passage wall and / or in connection with the chamfer surface and the outer surface of the

Femurnagels sections individually formed angles differ only in the range of a few degrees from each other. The deviation of the values of the individual angles are preferably <10 degrees, in particular <7 degrees, in particular <5 degrees, in particular <2 degrees, in particular <0.5 degrees. Preferably, the chamfer is formed at the lateral inlet end and / or at the medial outlet end such that no acute or sharp edges and / or corners are formed. The edges and / or corners that may be present in a manufacturing stage of the osteosynthesis tool are rounded.

The first bevel end region and the second bevel end region of the lateral

The inlet end and / or the medial outlet end may be complementary to each other, that is, have the same contour or the same shape, wherein the second bevel end region has a larger cross-section than the first bevel end.

In a further embodiment of the invention, the axis of the

Through hole and the longitudinal axis of the distal portion of the femoral nail an angle of 110 degrees - 160 degrees, in particular from 115 degrees - 155 degrees, in particular from 120 degrees - 150 degrees.

The axis of the passage opening is to be understood as the longitudinal axis of the passage opening, which is designed to run centrally from the lateral inlet end to the medial outlet end. The angle of the axis of the through hole and the longitudinal axis of the distal portion of the

Femoral nail is preferably associated with the CCD angle, which is generally the angle between the neck and shaft of the

Called femur.

The proximal portion of the femoral nail may have a diameter of 14-20 mm, especially 15-18 mm. The diameter of the distal portion of the femoral nail may have a diameter of 8-15 mm,

in particular from 10 to 13 mm.

Another aspect of the invention is based on that in the

Through opening of the femoral nail usable force carrier a

Femoral neck blade having a lateral and a medial portion and preferably a mounted within the femoral neck blade screw, wherein the cross section of the femoral neck blade in the lateral portion

complementary to the cross section of the passage wall of the through hole of the Femurnagels is formed and a rectangular cross section with

Having edge roundings, wherein the proximal and distal sides of the rectangular cross-section of the femoral neck blade are the shorter sides of the rectangular cross-section.

In a first embodiment of the invention, the force carrier consists only of a femoral neck blade. In a further possible embodiment of the invention, the force carrier consists of a combination of femoral neck blade and screw. The shape of the femoral neck blade in the region of the femur nail has a decisive influence on the stress distribution in the femoral nail and thus on the stability of the osteosynthesis aid during cyclic loading.

In order to avoid voltage spikes in the material of the osteosynthesis aid, in particular in the material of the femoral nail and / or the force carrier and thus to reduce the likelihood of cracking and crack propagation, the force carrier with rectangular cross-section edge rounding at least in the lateral section. As edge rounding are in particular rounded edges and / or rounded corners to understand.

The cross section of the femoral neck blade is preferably rectangular, in particular in the lateral region, wherein the edges of the rectangle are rounded or rounded and transition tangentially.

The edge radius of the edge fillets may have a value that corresponds at most to half the value of the proximal or distal side length of the rectangular cross section. In other words, the value of the edge radius is equal to or smaller than half the value of the narrow side of the rectangular cross section.

In a further embodiment of the invention, the edge radius of the edge fillets may have a value which corresponds to half the value of the proximal or the distal side length of the rectangular cross-section.

In an alternative embodiment of the invention, the edge rounding can also be carried out deviating from a circular shape, this only under the condition or condition applies that no edges and / or corners are created in the area of the edge rounding.

The shape of the femoral neck blade has in the implanted state in the region of the bone in conjunction with the screw covered by the power carrier or

The screw or support screw which is mounted within the femoral neck blade, preferably has a high tensile tensile strength in the axial direction, such as this z , B. occurs during intraoperative interfragmentary compression. At the same time the screw or support screw takes on part of the load-bearing forces through the contact with the femoral neck blade.

The femoral neck blade has, especially in the medial portion, a cranial blade leg and a caudal blade leg. The two blade legs are separated from each other or only in the lateral portion of the femoral neck blade, preferably monolithically, connected or fastened together. The cranial blade leg may be wider than the caudal blade leg. Since the femoral neck blade absorbs the majority of the carrying forces, the cranial portion of the femoral neck blade should be designed as large as possible, or with the largest possible contact surface for the forces directed from cranial to caudal.

Preferably, the cranial blade leg is formed correspondingly wider. The caudal portion of the femoral neck blade has a lower support function due to the usually lower bone density there. The caudal portion of the blade, particularly the caudal blade legs, is preferably formed with a high resistance to rotation of the bone about the femoral nail femoral sheath blade device. The width of the caudal

Blade leg can therefore be reduced in one embodiment of the invention, so that the thread of the screw or support screw is anchored optimally in the bone in order to achieve a high pull-out strength.

In addition, the femoral neck blade can be taken with reduced width of the caudal blade leg with less effort in the bone. Preferably, the caudal blade leg runs towards the medial end pointed and / or pyramidal and / or truncated pyramidal and / or

conical and / or frusto-conical too.

In a further embodiment of the invention, at least one

Side surface of the cranial blade leg and / or the caudal

Klingenschenkels have a cutout. Furthermore, it is conceivable that the four side surfaces of the cranial blade leg and the caudal

Blade legs each have a Abfräsong. As a side surface of the

Blade legs are the surfaces of the femoral neck blade or the blade leg to designate, which do not form the proximal and distal bearing surfaces to the bone when turning the femoral neck blade into the bone, but which limit the Kiingenschenkel in their width. The proximal or cranial and the distal or caudal surfaces of the blade legs can be milled so that milling edges arise. If the femoral neck blade or the two blade legs in the medial bone area at the four

Side surfaces are milled off, so that Abfräskanten arise

Side surfaces formed which provide greater resistance to rotation of the bone fragment around the implanted osteosynthesis tool. It is theoretically conceivable that the femoral neck blade of the force carrier is formed cranially or caudally asymmetric.

According to a further aspect of the invention, at least one bore, in particular a threaded bore, is formed in the proximal portion of the femoral nail between the passage opening and the proximal end of the femoral nail for receiving an anti-telescoping screw, wherein the bore axis of the bore and the axis of the passage opening obliquely, d. H. especially not parallel to each other.

Preferably, the bore is a continuous bore, so that a lateral inlet opening and a medial outlet opening are also formed in connection with this bore. In other words, the drilling axis and the axis of the passage opening are not parallel to each other. One or more Antiteleskopierschraube (s) aims or purposes the restriction of dynamization, in which the at least one

Antiteleskopierschraube the bone is a resistance when This should move due to lack of sufficient and insufficient cortical support as a result of a debris break in the direction of the force carrier on the rodent.

Preferably, in the proximal portion of the femoral nail at least two holes, in particular threaded holes, for receiving

Antiteleskopierschrauben trained. The holes are offset in the longitudinal extent of the femoral nail offset from one another. In other words, the holes are arranged one above the other in the longitudinal extension of the femoral nail.

In a plan view of the proximal end of the femoral nail, the holes may intersect each other in such a way that inserted therein

Antiteleskopierschrauben an angle of 10 degrees - 50 degrees, in particular from 25 degrees - 40 degrees, in particular from 30 degrees - 38 degrees. The point of intersection of the two inserted telescoping screws is preferably located outside of the femoral nail, in particular on the medial side spaced from the outer surface of the femoral nail.

The at least one anti-copy screw comprises a screw head and a machine threaded portion.

The at least one anti-copy screw preferably comprises one

Screw head, a bone thread section and a between the

Screw head and the bone threaded portion formed

Machine threaded portion. In other words, the

Antiteleskopierschraube a medial portion with a bone thread, which is located in the bone and a lateral portion with a machine thread, which is located in the femoral nail, and a screw head, outside the nail and the bone on. It is conceivable that the bone thread section has a cortical thread at least in sections. It is possible that the pitch of the bone thread and the machine thread are the same size. The machine thread can be designed to be catchy as well as multi-threaded.

The at least one Antiteleskopierschraube is for example in the

Femoral nail or the osteosynthesis Hilfsmittei screwed. Between the screw head and the head of the screw corresponding to the surface of the femur may be a, the support surface magnifying

Formed and / or arranged intermediate element, wherein the support element is preferably a bone plate or washer. The support of the lateral wall (trochanter major) is achieved by positioning a suitable implant or intermediate element under the screw head of one or more anti-telescoping screws in order to increase the support.

It should be noted that the inventive femur nail, the

Force carrier according to the invention and the inventive

Antiteleskopierschraube an osteosynthesis tool alone or in any conceivable combination claimed.

The invention will be explained below with reference to an embodiment and with the aid of figures.

Hereby show:

1 is a side view of an inventive osteosynthesis

Auxiliary device comprising a femur nail, a force carrier and two anti-copy screws;

FIG. 2 shows a side view of a femoral nail according to the invention of an osteosynthesis aid; FIG.

Fig. 3 is an Antiteleskopierschraube invention;

Fig. 4a-4d a femoral neck blade of an inventive

Force carrier of an osteosynthesis aid in

perspective, side and front view;

5a and 5b show a femoral nail according to the invention

Osteosynthesis aids in side view and in a sectional view according to the in Fig. 5a

illustrated section plane; 6a-6c show a femoral nail according to the invention

Osteosynthesis aids in side view and in sectional views according to the in Fig. 6a

shown sectional planes in another

Embodiment.

As can be seen from FIG. 1, an osteosynthesis aid 10 for the intramedullary treatment of subtrochanteric fractures and / or pertrochanteric fractures and / or femoral neck fractures comprises a femoral nail 20 which can be introduced into the medullary canal of a femur and has a distal section 21 and a femur

proximal portion 22, which has an obliquely to the longitudinal axis L (see Fig. 2) of the femoral nail extending through opening 25 with a lateral inlet end 26, a medial outlet end 27 and a passage wall 28, wherein in the passage opening 25, a power carrier 30 is inserted.

In the proximal portion 22 of the femoral nail 20 are between the

Through hole 25 and the proximal end 23 of the femur nail 20 two threaded holes 24 for receiving two Antiteleskopierschrauben 50 is formed, wherein the bore axes of the threaded bores 24 and the axis of the through hole 25 extend obliquely to each other. The holes, in particular the threaded holes 24, are aligned so that possible

Antiteleskopierschrauben 50 collision-free to each other and collision-free in relation to a force carrier 30 and come to rest within the femoral neck.

The force carrier 30 comprises a femoral neck blade 31 having a lateral portion 32 and a medial portion 33 and one within the

Femoral neck blade 31 mounted screw or support screw 35th

In Fig. 2, the femoral nail 20 is shown in a rotated by 90 degrees to the left. Thus, it is clear that the passage opening 25, starting from the lateral inlet end 26 to the medial outlet end 27 extends obliquely. For illustrated longitudinal axis L, the through hole 25 extends with the

Through wall 28 in the direction obliquely upward. The edges 29 at the lateral inlet end 26 have a chamfer 40 completely, such that a chamfer surface 41 oriented towards the passage wall 28 is formed. The drilling axes of the threaded holes 24 are asymmetrical to

Longitudinal axis L of the femur nail 20. It is conceivable that the drilling axes of the threaded holes 24 in the longitudinal sectional plane of the femoral nail 20 intersect. Furthermore, neither the bore axes of the threaded bores 24 nor the axis of the passage opening 25 and the bore axes of the threaded bores 24 run parallel to one another. Overall, an oblique _. , ie, not parallel, arrangement of the drilling axes and the axis of the through hole 25 formed to each other.

In the distal portion 21 of the femoral nail 20, two openings 15, namely transverse openings can be seen, in which z. B. bolts and / or

Locking screws for locking the femoral nail 20 with the diaphysis of the femur can be used.

In Fig. 3 is a Antiteleskopierschraube 50 of the invention

Osteosynthesis tool 10 shown. Accordingly, the

Antiteleskopierschraube 50 a screw head 51, a

Bone thread portion 52 and a formed between the screw head 51 and the bone thread portion 52, the machine thread portion 53. The bone thread portion 52 may be sections of a cortical thread. Between the machine thread portion 53 and the bone thread portion 52, a screw portion 54 may be formed which has no thread. The thread of the machine thread section 53 may be single or multi-threaded. In a particularly preferred embodiment of the invention, the thread of the

Machine threaded portion 53 have the same pitch as the thread of the bone thread portion 52.

The screw portion 55 formed between the machine screw portion 53 and the screw head 51 also has no thread. Thus, it is for example possible that between the screw head 51 and the screw head 51 corresponding surface of the femur, a the

Auflägef laugh enlarging intermediate element (not shown) is formed and / or arranged, wherein it is at the intermediate element to a support surface increasing implant, such. As a washer or a bone plate, can act. FIG. 4 shows a femoral neck blade 31 with a lateral section 32 and a medial section 33, wherein the cross section 36 of the femoral neck blade 31 shown for example in FIG. 4 d is formed in the lateral section 31 complementary to the cross section of the passage wall 28 and has a rectangular cross section Edge rounding 37, wherein the proximal side 38 and distal side 39 of the rectangular cross-section 36 are the shorter sides of the rectangular cross-section 36.

The edge radius r of the edge fillets 37 preferably has a value that corresponds at most to half the value of the proximal or distal side length I of the rectangular cross-section 36

Edge rounding avoids stress peaks in the material, which increases the likelihood of cracking and crack propagation in the material

Femoral nail 20 and in the force carrier 30 and in the femoral neck blade 31 under dynamic load of the osteosynthesis aid 10 avoided or

be reduced,

In a particularly preferred embodiment of the invention, the

Edge radius r of the edge fillets 37 has a value which corresponds to half the value of the proximal or distal side length I of the rectangular cross-section 36. From the illustration of Fig. 4c and 4d shows that the

Edge fillets 37 are characterized as a tangential transition of side and end faces.

The femoral neck blade 31 has, in particular in the medial section 33, a cranial blade leg 60 and a caudal blade leg 61. The two blade legs 60 and 61 are spaced apart from each other and form with the lateral portion 32 of the femoral neck blade 31 has a substantially U- or C-shape. The two blade legs 60 and 61 are connected to one another in the lateral section 32.

As can be seen from FIG. 4 a, the cranial blade limb 60 is wider than the caudal blade limb 61. Furthermore, in the width 62 of the cranial blade limb 60, a curvature of the blade limb 60 is formed. In the illustrated example, both the two side surfaces 63 and 63 'of the cranial blade leg 60 and the side surfaces 64 and 64' of the caudal blade leg are provided with a cut or a ground 67, 67 '. The width 65 of the caudal blade leg 61 is accordingly in comparison is greatly minimized to the width 62 of the cranial blade leg 60, so that the

Bone thread portion of the support screw 35 can be anchored sufficiently in the bone to achieve a high tear resistance. As shown in Fig. 4c, the caudal blade leg 61 tapers towards the medial end 69 of the blade leg.

Since the femoral neck blade 31 absorbs the majority of the carrying forces, it is important that the cranial blade leg 60 has the largest possible contact surface 66. Due to the cutouts 67, 67 'in the side surfaces 63, 63' and 64, 64 'of the femoral neck blade 31, the surfaces thus formed provide the greatest possible resistance to rotation. Due to the cutouts 67 and 67 'further edges 68, 68' are introduced into the surface of the femoral neck blade 31. In the area of the caudal blade leg 61, the

Milled cuts 67 'extend to the lateral portion 32 of the femoral neck blade 31 zoom.

FIG. 5b shows a sectional view of the femoral nail 20 according to section A-A in FIG. 5a. Accordingly, the edges at the lateral entry end 26 are fully provided with a chamfer 40, which forms a chamfer surface 41 oriented towards the passage wall 28. The chamfer 40 may have a depth t of 0.05 mm to 5.0 mm, in particular from 0.075 mm to 4.0 mm, in particular from 0.1 mm to 3.0 mm. The chamfer surface 21 and the passage wall 28 include an edge angle a or α ', which has a value> 90 degrees. The edge angle α or α 'at the lateral entry end 26 preferably has approximately the same value. As approximately equal values, such angular dimensions are to be understood that deviate from one another by a maximum of 7 degrees, in particular by a maximum of 5 degrees, in particular by a maximum of 2 degrees, in particular by a maximum of 0.5 degrees.

Since the edges 29 of the lateral entry end 26 are provided with a chamfer 40, without appreciably weakening the cross section of the femur nail 20 in the region of the passage of the force carrier 30, an essential Improved stability of the osteosynthesis tool 10 under dynamic load with respect to the femoral nail 20 in the region of the through hole 25 and the force carrier 30 located therein achieved.

FIGS. 6b and 6c show sectional views of the femoral nail 20 in another embodiment according to section AA and section BB of FIG. 6a. According to this embodiment, the lateral entry end 26 is fully enclosed with a chamfer 40 which has a chamfer surface oriented towards the passage wall 28 41 forms provided. In addition, the medial outlet end 27 is fully provided with a chamfer 40 'which forms a chamfer surface 4 1' oriented towards the passage wall 28.

The chamfer surfaces 41, 41 'are bounded in each case by a first fully formed chamfer end region 42, 42' adjoining the passage wall 28 and a second, fully formed chamfer end region 43, 43 'adjoining the outer surface 18 of the femur nail 20.

Both the first bevel end regions 42, 42 'and the second

Bevel end 43, 43 'are rounded. These roundings are both in the cranial regions 44, 44 'of the inlet opening 26 and the

Outlet opening 27, as well as in the caudal areas 45, 45 'of the

Inlet opening 26 and the outlet opening 27 is formed. In addition, the rounded portions in the region of the webs 46, 46 'of the inlet opening 26 and the outlet opening 27 are formed, As webs 46, 46' are respectively the

Connecting walls between the caudal areas 45, 45 'and the cranial areas 44, 44' of the respective ends 26 and 27 to understand. 2, the lateral entry end 26 is also shown with a cranial region 44, a caudal region 45 and the two connecting webs 46.

The first bevel end region 42, 41 'is in each case rounded off in such a way that the

Through wall 28 and the chamfer surface 41, 4 1 'an angle ß, ß' include, which has a value greater than 90 °.

The second bevel end region 43, 43 'is in each case rounded off in such a way that the chamfer surface 41, 41' and the outer surface 18 of the femur girder 20 enclose an angle φ, φ, which has a value greater than 90 °. Preferably, the angles ß, ß 'and φ, φ' are fully formed substantially the same.

LIST OF REFERENCE NUMBERS

10 osteosynthesis aids

15 transverse opening or slot

18 outer surface femur nail

20 femoral nail

21 distal section femoral nail

22 proximal section femoral nail

23 proximal end femoral nail

24 threaded hole

25 passage opening

26 lateral entry end

27 medial exit end

28 passage wall

29 edge entry end

30 power carrier

31 femoral neck blade

32 lateral section femoral neck blade

33 medial section femoral neck blade

35 carrying screw

36 cross section

37 edge rounding

38 proximal side cross section

39 distal side cross section

40, 40 'bevel

41, 4 1 'chamfer surface

42, 42 'first bevel end

43, 43 'second bevel end

44, 44 'cranial region entry end / exit end

45, 45 'kaudater area entrance / exit end

46, 46 'bridge entry end / exit end

50 anti-copy screw

51 screw head 52 bone thread section

53 Machine thread section

54 screw section

55 screw section

60 cranial blade legs

61 caudal blade leg

62 Width of cranial blade leg

63, 63 'lateral surface of cranial blade legs

64, 64 'side surface of caudal blade leg

65 Brette caudal Klingerkelkel

66 bearing surface

67, 67 'milling

68, 68 'edges

69 Medial end of caudal blade leg r Edge radius

t depth of the chamfer

I distal side length

L longitudinal axis femoral nail

α, α 'edge angle

β, ß 'angle through wall chamfer surface φ, φ' angle chamfer surface outer surface

Claims

claims

1. Osteosynthesis aids (10) for intramedullary care

subtrochanteric fractures and / or pertrochanteric fractures and / or femoral neck fractures, comprising a femoral nail (20) insertable into the marrow of a femur, having a distal portion (21) and a proximal portion (22) oblique to the longitudinal axis (L) of the femoral nail (20) extending through opening (25) having a lateral inlet end (26), a medial outlet end (27) and a

Through wall (28), wherein in the passage opening (25), a power carrier (30) can be used,

d a d u rc h e ke n ze ze ch n et that

the lateral entry end (26) and / or the medial exit end (27) have a chamfer (40, 40 ') completely in such a way that one for

Through wall (28) facing chamfer surface (41, 41 ') is formed.

2. osteosynthesis aid (10) according to claim 1,

d ad rc h e s n e s n e s that

the chamfer (40, 40 ') has a depth (t) of 0.05 mm - 5.0 mm, in particular of 0.075 - 4.0 mm, in particular of 0.1 mm - 3.0 mm.

3. osteosynthesis aid (10) according to claim 1 or 2,

characterized in that net

the chamfer surface (41, 41 ') of a first, on the passage wall (28) adjacent, in particular full-circumference, bevel end region (42, 42 ^* ) and of a second on the outer surface (18) of the femoral nail (20) adjacent, in particular full-scale, Bevel end region (43, 43 ') is limited.

4. osteosynthesis aid (10) according to claim 3,

dad u rch geke nnzeich n et that

the first bevel end region (42, 42 ') and / or the second bevel end region (43, 43') is / are rounded off.

5. osteosynthesis aids (10) according to claim 4,

dadu rch marked that the first bevel end region (42, 42 ') is rounded off in such a way that the

Through wall (28) and the chamfer surface (41, 41 ') an angle (ß, ß') include, which has a value greater than 90 °, and / or the second bevel end region (43, 43 ') is rounded such that the chamfer surface (41, 41 ') and the outer surface (18) of the femur (20) include an angle (φ, φ') having a value greater than 90 degrees,

6. osteosynthesis aid (10) according to any one of claims 1 to 5,

dad u rch netsi ch n et that

the axis of the passage opening (25) and the longitudinal axis of the distal portion (21) of the femur (20) an angle of 110 degrees - 160 degrees, in particular from 115 degrees - 155 degrees, in particular from 120 degrees - 150 degrees.

7. force carrier (30) for an osteosynthesis aid (10), in particular according to one of claims 1 to 6, for intramedullary care

subtrochanteric fractures and / or pertrochanteric fractures and / or femoral neck fractures, wherein the osteosynthesis aid (10) insertable into the medullary cavity of a femur femur nail (20), with a distal portion (21) and a proximal portion (22), the one obliquely to the longitudinal axis (L) of the femoral nail (20) extending

Through opening (25) having a lateral inlet end (26), a medial outlet end (27) and a passage wall (28) comprises, wherein in the through hole (25) of the force carrier (30) is insertable,

there is no sign that

the force carrier (30) comprises a femoral neck blade (31) having a lateral (32) and a medial section (33), the cross section (36) of the femoral neck blade (31) in the lateral section (32) being complementary to the cross section of the passage wall (28) is trained and one

having rectangular cross-section (36) with edge fillets (37), wherein the proximal (38) and distal (39) sides of the rectangular cross-section (36) of the femoral neck blade (31) are the shorter sides of the rectangular cross-section (36).

8. force carrier (30) according to claim 7,

dadu rc hge ken nze i ch net that the edge radius (r) of the edge fillets (37) has a value which corresponds at most to half the value of the proximal or distal side length (I) of the rectangular cross-section (36),

9. power carrier (30) according to claim 8,

That's how I think it is

the edge radius (r) of the edge fillets (37) has a value which corresponds to half the value of the proximal or distal side length (I) of the rectangular cross-section (36)

10. power carrier (30) according to any one of claims 7 to 9,

I think that's what I mean

the femoral neck blade (31), in particular in the medial section (33), has a cranial blade leg (60) and a caudal blade leg (61).

11. power carrier (30) according to claim 10,

there is no sign that

the cranial blade leg (60) is wider than the caudal blade leg (61).

12. force carrier (10) according to claim 10 or 11,

d e a n d i nc e s that

at least one side surface (63, 63 ') of the cranial blade leg (60) and / or at least one lateral surface (64, 64') of the caudal one

Blade leg (61) has a cutout (67, 67 *).

13. power carrier (30) according to claim 12,

d a d u rc h e ke n ze i c h n et that

the four side surfaces (63, 63 '64, 64') of the cranial blade leg (60) and the caudal blade leg (61) each have a cutout (67,

67 ').

14. A force carrier (30) according to any one of claims 7 to 13,

marked by

a screw (35) mounted within the femoral neck blade (31).

15. osteosynthesis aid (10) according to any one of claims 1 to 6 and / or with a force carrier (30) according to any one of claims 7 to 14, for the intramedullary supply of subtrochanteric fractures and / or pertrochanteric fractures and / or femoral neck fractures, comprising a in the medullary canal of a femur insertable femoral nail (20) having a distal portion (21) and a proximal portion (22) extending obliquely to the longitudinal axis (L) of the femoral nail (20)

Through opening (25) having a lateral inlet end (26), a medial outlet end (27) and a passage wall (28), wherein in the passage opening (25) is a force carrier (30) can be used, dadu rch ken n zei ch n et that

in the proximal portion (22) of the femoral nail (20) between the

Through hole (25) and the proximal end (23) of the femoral nail (20) at least one bore, in particular a threaded bore (24) for receiving a Antiteleskopierschraube (50) is formed, wherein the drilling axis and the axis of the through hole (25) obliquely to each other run.

16. osteosynthesis aid (10) according to claim 15,

there are signs that

the Antiteleskopierschraube (50) a screw head (51) and a

Machine thread Absektion (53).

17. osteosynthesis aid (10) according to claim 16,

d a d u rc h e ke n ze i c h n et that

the anti-copy screw (50) comprises a bone screw portion (52), wherein between the screw head (51) and the

Bone thread portion (52) of the Maschinengewindeabsehnitt (53) is formed.

18. osteosynthesis aids (10) according to claim 17,

there is no such thing that

the thread of the machine thread section (53) is designed to be catchy or more continuous.

19. osteosynthesis aid (10) according to claim 17 or 18,

d a d u rch geken nzeich n et that

the bone thread section (52) has a cortical thread.

20. An osteosynthesis aid (10) according to any one of claims 16 to 19, characterized in that there are no

the thread of the machine thread section (53) and the thread of the bone thread section (52) have the same pitch,

21. osteosynthesis aid (10) according to any one of claims 16 to 20,

I can tell you that

between the screw head (51) and the surface of the femur corresponding to the screw head (51), the bearing surface

enlarging intermediate element is formed and / or arranged, wherein the intermediate element is preferably a bone plate or washer washer.