CN112716586A

CN112716586A - Intramedullary fixation device for femoral fracture

Info

Publication number: CN112716586A
Application number: CN202110093428.5A
Authority: CN
Inventors: 李晖; 孟祥翔; 彭丹
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-01-25
Filing date: 2021-01-25
Publication date: 2021-04-30
Anticipated expiration: 2041-01-25
Also published as: CN112716586B

Abstract

The invention discloses a femur fracture intramedullary fixation device, which comprises an outer sleeve, a core bar, a blade set and a driving assembly, wherein a plurality of axial cutter grooves are uniformly distributed on the peripheral edge of a front end pipe orifice of the outer sleeve, an inward concave annular groove is formed near the outer edge of the pipe orifice, a threaded section is arranged on the outer side of a rear end pipe orifice of the outer sleeve, a tensioning nut is arranged on the outer side of the threaded section, the core bar is sleeved in the outer sleeve in a matching manner, the blade set comprises a rigid ring and a plurality of blades and a movable sleeve in threaded connection with the outer side of the threaded section of the core bar, and the movable sleeve drives each blade to unfold and fold. The invention can be conveniently implanted into the medullary cavity of the femur and is easy to adjust and fix, after each blade is unfolded, the invention adopts an inverted hanging mode and an outward pulling mode, so that a plurality of uniformly distributed blades simultaneously exert pulling force on the expanded part of the inner cavity of the femoral neck, thereby not only promoting the two ends of the fracture to be close inwards, but also effectively preventing the fracture part from rotating, and having simple and reliable use.

Description

Intramedullary fixation device for femoral fracture

Technical Field

The invention belongs to the technical field of reduction and fixation devices for femoral neck fracture, and particularly relates to an intramedullary fixation device for femoral fracture.

Background

Fractures of the neck and tuberosity of the femur are common frequently encountered diseases of the old. When the femoral neck fracture or intertrochanteric fracture is fixed by a screw and nail plate system, the traditional internal fixation method for the femoral neck fracture is many, and joint replacement is often finally performed due to difficult operation and many complications. The femur neck has special anatomical structure, a shaft angle and an anteversion angle on different planes, and the position is deep and hidden, so that the positioning guide pin is difficult to be correctly placed. When the internal fixation is used for treating the fracture of the femoral neck and the femoral tuberosity, a guide needle is firstly placed for positioning. The main factor of the traditional fixing method for inserting the guide pin is the problem of weak fixation, which is usually performed according to the clinical experience of doctors.

In another aspect, the femoral neck includes an outer hard bone portion and an inner loose bone portion, the loose bone portion filling the entire bone cavity as shown in FIG. 15. The loose bone part of the inner layer has large volume and low density, the intramedullary nail has fixing strength when being fixed on the hard bone part of the outer layer, but the fixing strength when being fixed on the loose bone part of the inner layer is insufficient, and most of the intramedullary nails are actually positioned on the loose bone part of the inner layer. The outer diameters of the root part and the tail end of the femoral neck are larger than that of the neck part, and part of the intramedullary nail is exposed out of the neck part, so that the problem of poor firmness in fixation of the intramedullary nail is caused.

In the prior art, a structure similar to an expansion wire is adopted, the inner wall of a bone cavity is supported in the femoral neck bone cavity through a distraction expansion part, and actually, the inner wall is supported at a loose bone part and compresses the loose bone part to the hard bone inner wall, and the expansion type bone pressing device has the following problems: (1) the expansion surface is a cambered surface, loose bone parts can not be completely stripped and directly contact the inner wall of the hard bone, so that the firmness after compression is insufficient, (2) after expansion and compression, enough constraint force of the femoral neck in the circumferential direction can not be provided, the femoral neck can be dislocated due to rotation, (3) the destructiveness of the loose bone parts is high, when the inner end of the loose bone parts is expanded, all loose bone parts in the bone cavity of the femoral neck are damaged, (4) the expansion part at the inner end of the loose bone parts can not be completely matched with the inner wall of the bone cavity of the femoral neck, and can not provide enough anti-torsion strength, the fracture reduction of a femoral neck fracture patient needs to be maintained at the internal rotation position of the lower limb, the point is embedded by the acetabulum and is not completely spherical, and the body position rotation can bring large torsion to an internal support part, so that the expansion part. For example, the "expansion fixing femoral head inner support body" provided by the publication No. CN 202146350U includes a support main body and an inner expansion screw, the support main body is sleeved outside the inner expansion screw, the top of the support main body is arc-shaped, the support main body is provided with a radial expansion wing, the expansion wing is composed of a plurality of fins, an expansion gap is formed between each fin, the inner expansion screw is provided with an expansion section, the expansion section can expand the expansion wing after the inner expansion screw is placed in the support main body, and the support main body is in threaded connection with the inner expansion screw. Also, for example, a self-locking composite interlocking intramedullary nail is fixed between the femoral tuberosities with publication number CN 2659365Y. And other solutions applied to the intertrochanteric femoral cavity for support, approximately in the form of expansion pins. The expansion nail is implanted into the inner cavity of the femoral bulge part by generally utilizing the principle of the expansion nail, the expansion degree of each expansion blade is limited, and the expansion blade is not enough to form a large enough inner support body, the screw is required to be screwed inwards to be pushed, the screw can easily reach the limit support and is propped against the end part of the inner cavity of the femur and can not continuously advance, so that the continuous expansion can not be caused, the expansion direction of each expansion blade is in an outward expansion shape, the hanging connection relation can not be formed on the inner cavity of the femoral bulge part, the expansion blade can not go deep into fluffy bone due to large width and is contacted with the hard bone wall of the outer layer, the problems of insufficient traction strength and insufficient anti-rotation capacity are caused, and secondary damage accidents can be caused by the infirm fixing state.

Disclosure of Invention

Aiming at the defects and problems of various fixing modes of the conventional femoral neck, the invention provides a method for realizing the unfolding of blades in an inner cavity between femoral tuberosities to form an inverted relation by screwing a small knob at the tail end, and locking and fixing by screwing a tensioning nut, so that the fracture part of the femoral neck can be effectively fixed from the inside, and enough twisting prevention force can be provided.

The invention adopts the technical scheme that the intramedullary fixing device for femoral fracture mainly comprises an outer sleeve, a core rod, a blade group, a driving assembly and the like. Wherein, the periphery of the front end pipe orifice of the outer sleeve is evenly distributed with a plurality of cutter grooves along the axial direction, the outer circumferential wall near the pipe orifice is provided with an inward concave annular groove, the outer side of the rear end pipe orifice of the outer sleeve is provided with a thread section, the outer side of the thread section is provided with a tensioning nut, the core bar comprises a screw rod section, the rear end of the core bar is connected with a small end knob, the core bar is sleeved in the outer sleeve in a matching way, the whole core bar can be driven to rotate relative to the outer sleeve by rotating the small end knob, the blade group comprises a rigid ring and a plurality of blades, each blade comprises a shaft hole at the tail end and an arc-shaped cutter head at the head end, each blade is respectively sleeved on the rigid ring through the shaft hole at the tail end, each blade can freely rotate relative to the rigid ring, the rigid ring is fixedly arranged in the annular groove, each blade is arranged in the corresponding cutter groove, the driving component, the periphery of the outer side of the movable sleeve is respectively provided with a protruding hinge seat, each hinge seat is respectively provided with a shaft hole and is respectively hinged with a push-pull rod through a pin shaft, the inner side of the middle part of each blade is also distributed with pin holes, and the tail end of each push-pull rod is respectively hinged in the corresponding pin hole through a pin shaft.

Furthermore, the driving assembly also comprises a fixed sleeve fixed at the front end of the outer sleeve, and the inner end of the core rod is sleeved in the fixed sleeve and can freely rotate.

And a sleeve head is fixed at the inner end of the mandrel in a sleeved mode, the sleeve head is sleeved in a central hole of the fixed sleeve in a matched mode, a base plate is sleeved at the tail end of the mandrel, namely the end portion of the sleeve head, the base plate is fixed at the end portion of the sleeve head through a penetrating wire, the penetrating wire enters the central screw hole in a spiral mode, and a small matching gap exists between the base plate and the fixed sleeve so that the base plate can rotate along with the sleeve head, namely the core rod.

In order to prevent the fixed sleeve from rotating relative to the outer sleeve, the outer edge of the fixed sleeve and the inner edge of the pipe orifice of the outer sleeve can be provided with a combined screw hole and a locking wire.

The end face of the fixed sleeve is provided with a pair of blind holes, and the fork-shaped spanner is clamped into the corresponding blind holes to carry out screwing assembly operation on the blind holes.

The outer edge of the cutter head of the blade is outwards protruded and is in a tooth shape, and the end part of the cutter head of the blade can also be in a hook shape.

When the outer side of the thread section is provided with the tensioning nut, a gasket which is close to the surface curvature of the sclerotin is sleeved on the tensioning nut.

4-8 cutter grooves along the axial direction are arranged at the front end of the outer sleeve, and a cutter blade with the matched thickness is respectively arranged in each cutter groove along the axial direction.

Still including implanting and being fixed in the intramedullary nail of thighbone intracavity, the near-end of intramedullary nail is provided with the side hole that runs through, the outer tube match run through install in intramedullary nail near-end side hole, tensioning nut and its gasket support are at the lateral wall of intramedullary nail side hole. When the intramedullary nail is matched with the device, the special-shaped hole matching or key matching is limited, namely, a key can be arranged on the outer side of the outer sleeve and a key groove is arranged on the side hole of the intramedullary nail.

The outer end of the outer sleeve is fixed with a wall plate, the center of the outer sleeve is provided with a through hole, a small knob at the tail end is led out from the through hole, at least one pair of positioning holes are arranged at the eccentric position on the end plate, a clamping piece is fixedly inserted into each positioning hole, the outer side circumference of the tensioning nut is provided with a convex-concave groove, and the clamping piece is clamped in the groove at the outer side of the circumference of the tensioning nut. When the inner side of the tensioning nut is sleeved with a gasket consistent with the surface curvature of the bone, the gasket can be provided with an insertion hole, and the clamping leading-out fork rod is inserted into the insertion hole, so that the rotation of the tensioning nut can be prevented, and the stability of the outer sleeve can be further improved.

The invention has the beneficial effects that: the device can implant in the thighbone marrow cavity very conveniently and adjust and fix very easily, adopts the mode of hanging upside down and drawing outward after each blade expandes among the device, makes a plurality of evenly distributed's blade exert pulling force outside the thighbone neck inner chamber inflation part simultaneously, not only can impel the fracture both ends inwards to be close to, can effectively prevent the fracture position moreover and rotate, and is simple to use reliable.

The device provided by the invention can also realize that the blades can be automatically unfolded to different degrees so as to contact with the inner cavity wall between the femoral tuberosities to form an independent hanging connection relationship, so that the blades can bear the external pulling pressure, the pulling force is uniformly dispersed, and the local over-compression is prevented.

Drawings

Fig. 1 is a schematic view of the present invention in use.

FIG. 2 is a schematic view of the present invention.

Fig. 3 is a schematic view of the structure of the outer sleeve of fig. 2.

Fig. 4 is a schematic view of the core rod of fig. 2.

Fig. 5 is a schematic view of the blade assembly of fig. 2.

Fig. 6 is an enlarged view of a cross-section of fig. 2.

Fig. 7 is a schematic view of the structure of the blade of fig. 2.

Fig. 8 is a through nail structure view.

Fig. 9 is a view showing the structure of the cuff.

Fig. 10 is a structure diagram of the nest.

Fig. 11 is a structure view of the movable sleeve.

FIG. 12 is a second schematic view of the present invention.

Fig. 13 is a schematic view of the fig. 12 blade in an extended state.

Fig. 14 is a view of the blade of fig. 12.

Fig. 15 is a front view of the core rod of fig. 12.

Fig. 16 is a schematic view of a six-blade configuration.

Fig. 17 is a schematic view of a linkage blade structure.

Detailed Description

Example 1: an intramedullary fixation device for femoral fracture is disclosed, as shown in figure 1, the device is placed in the medullary cavity of the femoral neck fracture part, after the corresponding area is drilled and disinfected, one end of the device is implanted into the deep part of the medullary cavity of the femoral neck, and can not be pushed, then the small end knobs are sequentially adjusted to simultaneously expand a plurality of blades in the device until the blades can not be continuously screwed, and then the tightening nuts are screwed to integrally withdraw the device until the blades are supported in the intramedullary cavity of the femoral neck, and the device can not be screwed. Thus, the device can be conveniently implanted in the femoral medullary cavity and easily adjusted and fixed. When the device is used, the tensioning nut presses a steel plate gasket, and the steel plate is matched and attached to the surface of the bone.

The specific structure of the device is shown in fig. 2, and comprises an outer sleeve 10, a core rod 20, a blade group 30 and a driving assembly 40.

As shown in fig. 3, a plurality of axial cutter grooves 11 are uniformly distributed on the peripheral edge of the front end pipe orifice of the outer sleeve 10, an inward concave annular groove 12 is arranged near the pipe orifice, a threaded section 13 is arranged on the outer side of the rear end pipe orifice of the outer sleeve, as shown in fig. 2, a tensioning nut 14 is arranged on the outer side of the threaded section 13, and a gasket 15 close to the surface curvature of the bone is sleeved on the gasket.

As shown in FIG. 4, the core rod 20 comprises a screw section 21, and a small end knob 21 is connected to the rear end of the core rod 20, and the whole core rod 20 can be driven to rotate by rotating the small end knob 21.

As shown in FIG. 1, the core rod 20 is fit-fitted in the outer sleeve 10, and both can rotate.

As shown in fig. 5, the blade set 30 includes a rigid ring 31 and a plurality of blades 32, each blade 32 includes a terminal axial hole 33 and a head arc-shaped cutter head 34, each blade 32 is respectively sleeved on the rigid ring 31 through the terminal axial hole 33, and each blade 32 can freely rotate relative to the rigid ring 31. When in processing, the rigid ring is provided with a notch in advance, the rigid ring is expanded by a tool so that the notch is enlarged, the shaft holes of the blades penetrate into the rigid ring through the notch in sequence, and then the notch is welded, ground and polished.

As shown in fig. 2 and 16, the rigid ring 31 is inserted through the front end of the outer sleeve 10, and the plurality of knife grooves 11 are formed at the front end of the outer sleeve, so that the rigid ring 31 can press the end of the outer sleeve 10 to be appropriately converged and then have a smaller diameter, and when the rigid ring 31 is pressed, the blades are simultaneously arranged in the corresponding knife grooves 11, and the end of the outer sleeve returns to a natural state after the rigid ring 31 enters the annular groove 12. Thus, each blade 32 is able to oscillate freely within the corresponding pocket 11.

As shown in fig. 6, the driving assembly 40 includes a fixed sleeve 41 fixed at the front end of the outer sleeve 10 and a movable sleeve 42 screwed on the outer side of the threaded mandrel section 21 (see fig. 8-11 for the respective assembly views of the driving assembly 40), and protruding hinge seats 43 are respectively provided on the outer peripheral edges of the movable sleeve 42, and each hinge seat 43 is provided with an axial hole 44 and is respectively hinged with the push-pull rod 36 through a pin. As shown in fig. 6 and 7, pin holes 35 are further distributed on the inner side of the middle portion of each blade 32, and the tail end of each push-pull rod is hinged in the corresponding pin hole 35 through a pin shaft.

As shown in fig. 6, the inner end of the core rod 20 is freely rotatably sleeved in the stator. Specifically, a sleeve head 45 is fixedly sleeved on the inner end of the mandrel, the sleeve head 45 is sleeved in a central hole of the fixed sleeve 41 in a matching mode, a backing plate 46 is sleeved on the tail end of the mandrel, namely the end portion of the sleeve head, as can be seen in the figure, the backing plate 46 is fixed on the end portion of the sleeve head 45 through a through wire 47, the through wire is screwed into the central screw hole 23, and a small matching gap exists between the backing plate 46 and the fixed sleeve 41 so that the backing plate 46 can rotate along with the sleeve head, namely the core rod.

It can be seen that the rigid ring 31 is constrained to the outer sleeve 10 from the outside of the front end thereof, and the stator 41 is supported from the inside of the front end of the outer sleeve 10, so that both the stator and the rigid ring can be firmly fixed to the front end of the outer sleeve by the cooperation of the rigid ring 31 and the stator 41. As can be seen, the stator 41 is screwed inside the port at the front end of the outer sleeve.

In order to prevent the fixed sleeve from rotating relative to the outer sleeve, a combined screw hole 48 is arranged on the outer edge of the fixed sleeve and the inner edge of the pipe orifice of the outer sleeve, and a locking wire is installed. In order to improve the convenience of mounting and dismounting the fixed sleeve 41, a pair of blind holes 49 are arranged on the end surface of the fixed sleeve, and a fork-shaped spanner is clamped into the corresponding blind holes to carry out screwing assembly operation.

In order to improve the clamping degree of the blade, the outer edge profile of the cutter head 34 of the blade is outwards protruded and arranged in a tooth shape, the end part of the cutter head 34 of the blade can also be arranged in a hook shape, and the outer profile of the cutter head of the blade is preferably designed to be approximately matched with the inner wall of the convex part of the intramedullary cavity of the femoral neck so as to improve the contact area.

From the assembled relationship of fig. 2 and 6, the mandrel 20 can be rotated within the outer sleeve 10 by rotating the small end knob 22, but the blades 32 are connected to the throw sleeve 42 by the push-pull rod 36 so that the throw sleeve 42 cannot rotate, and thus the throw sleeve can move axially along the mandrel as the mandrel is rotated. The axial movement of the movable sleeve forces the push-pull rod 36 to drive or pull the corresponding blade 32 for unfolding or folding. When the tool is used, the tool is inserted into the inner cavity of the neck of the femur to a deep position along a drill hole, the small end knob 22 is screwed to simultaneously unfold the blades, when the blades are unfolded to a certain degree or unfolded to a non-screwing degree, the tensioning nut 14 is screwed to pull the whole outer sleeve outwards, and the blades are further pressed to be clamped on the inner wall of the convex part of the inner cavity of the neck of the femur to form a stable supporting relation.

Example 2: on the basis of example 1, a fixing device is used which enables the blades to adapt to the degree of spreading. As shown in fig. 15, the core rod 20 has a front tapered axle head 24 at a front end thereof and a rear tapered axle head 26 at a rear end thereof, which are respectively fitted to front and rear ends of the outer sleeve 10 through bushings 25 and are constrained to rotate only but not to move axially.

Specifically, a front spindle nose 24 at the front end of the core rod is sleeved in the front fixed sleeve 41 through a shaft sleeve, a rear spindle nose 26 at the rear end of the core rod is sleeved in the rear fixed sleeve through a shaft sleeve, and the rear fixed sleeve is fixed at the rear end of the outer sleeve. The front end of the core rod is sleeved with a steel ring 38 at the inner side of the fixed sleeve, the peripheral edge of the steel ring extends outwards to form an outward-warped elastic sheet 39, and each elastic sheet 39 penetrates through the corresponding cutter groove 11 and then is supported at the inner side of the corresponding blade 32. The pin hole in the middle of the blade is a strip-shaped hole 37 as shown in fig. 14, and the pin shaft at the tail end of the push-pull rod 36 is sleeved in the strip-shaped hole 37 in a matching manner and can slide.

Thus, as shown in fig. 12 and 13, when the small end knob 22 is turned to drive the moving sleeve 42 to move forward, the unfolding power of the blades comes from the elastic pieces 39 instead of the push-pull rod 36, and the elastic pieces 32 are unfolded as shown in fig. 13, it should be noted that the blades are slightly different in degree and are mainly limited by the position and shape of the inner wall of the intramedullary canal of the femoral neck, and this scheme can ensure that all the blades can be unfolded and supported on the inner side wall of the intramedullary canal of the femoral neck. When the tightening nut 14 is adjusted, the outer sleeve is driven to move outwards so as to pull the blades to move outwards simultaneously, the blades can be supported on corresponding positions on the inner side wall of the intramedullary cavity of the femoral neck respectively to play a supporting role, and the supporting force of each blade is transmitted to the rigid ring 31 through the shaft sleeve 33 at the tail end of each blade and then transmitted into the annular groove 12 of the outer sleeve. Similarly, when the tool is removed, the tensioning nut 14 is first screwed to release the tension of the outer sleeve and the blades, and then the small end knob 22 is turned to drive the movable sleeve 42 to move backwards, the power for unfolding the blades comes from the push-pull rods 36, and the tension overcomes the elastic force of the elastic sheets, so that the elastic sheets are compressed as shown in fig. 12.

Example 3: based on the embodiment 1 or 2, the present invention can adopt six blades uniformly arranged at the front end of the outer sleeve as shown in fig. 16, and the driven sleeve and the push-pull rod synchronously drive the expansion and the contraction.

The above embodiments are only exemplary embodiments of the present invention, and other structural variations of the present invention are possible, such as designing the ratio of the length of each blade to the outer casing to optimize the application. However, it is also possible to shorten the length of each blade, while increasing the degree of radial extension of each blade as shown in fig. 17. Specifically, each group of blades is additionally provided with a first auxiliary rod 51 and a second auxiliary rod 52 shown in fig. 17, the first auxiliary rod is sleeved on the rigid ring 31 through a shaft hole at the tail end of the first auxiliary rod, each first auxiliary rod can freely rotate relative to the rigid ring 31, the second auxiliary rod is hinged on a shaft hole 44 of a hinge seat 43 corresponding to the outer side of the movable sleeve through a pin shaft, and each second auxiliary rod can freely rotate relative to the hinge seat. The middle parts of the first auxiliary rod and the second auxiliary rod are hinged together through a pin shaft 53 respectively. Each blade 32 comprises a tail end shaft hole 33 and a head end arc-shaped cutter head 34, each blade 32 is sleeved on the first auxiliary rod through the tail end shaft hole 33, and each blade 32 can rotate freely relative to the first auxiliary rod. Two tail ends of each auxiliary rod are respectively provided with an axle hole and are respectively hinged with a push-pull rod 36 through a pin shaft. The inner side of the middle part of each blade 32 is also distributed with pin holes 35, and the tail end of each push-pull rod is hinged in the corresponding pin hole 35 through a pin shaft. For example, the device is fixedly mounted in cooperation with an intramedullary nail placed in the femoral bore. For example, a locking structure is provided at the tightening nut position to prevent rotation thereof, etc.

Claims

1. The intramedullary fixing device for femoral fracture is characterized by comprising an outer sleeve (10), a core rod (20), a blade group (30) and a driving assembly (40), wherein a plurality of axial cutter grooves (11) are uniformly distributed on the peripheral edge of a front end pipe orifice of the outer sleeve (10), an annular groove (12) which is recessed inwards is formed in the outer circumferential wall near the pipe orifice, a threaded section (13) is arranged on the outer side of a rear end pipe orifice of the outer sleeve, a tensioning nut (14) is sleeved on the threaded section (13), the core rod (20) comprises a screw rod section (21), a small tail end knob (21) is connected to the rear end of the core rod (20), the core rod (20) is sleeved in the outer sleeve (10) in a matching mode, the small tail end knob (21) can be rotated to drive the whole core rod (20) to rotate relative to the outer sleeve (10), and the blade group (30) comprises a rigid ring (31) and a plurality of blades (32), each blade (32) comprises a shaft hole (33) at the tail end and an arc-shaped cutter head (34) at the head end, each blade (32) is respectively sleeved on the rigid ring (31) through the shaft hole (33) at the tail end, each blade (32) can rotate freely relative to the rigid ring (31), the rigid ring (31) is fixedly sleeved in the annular groove (12), each blade is positioned in the corresponding cutter groove (11), the driving component (40) comprises a movable sleeve (42) which is in threaded connection with the outer side of the core rod threaded section (21), the periphery of the outer side of the movable sleeve (42) is respectively provided with a convex hinging seat (43), each hinging seat (43) is respectively provided with a shaft hole (44) and is respectively hinged with a push-pull rod (36) through a pin shaft, the inner side of the middle part of each blade (32) is also distributed with pin holes (35), the tail ends of the push-pull rods are hinged in the corresponding pin holes (35) through pin shafts respectively.

2. The intramedullary fixation device of claim 1, wherein the drive assembly (40) further comprises a fixed sleeve (41) fixed to the front end of the outer sleeve (10), the inner end of the core rod (20) being rotatably received in the fixed sleeve.

3. The intramedullary fixation device for femoral fractures according to claim 2, characterized in that a sleeve head (45) is fixed in the inner end of the mandrel, the sleeve head (45) is sleeved in the central hole of the fixed sleeve (41) in a matching way, a backing plate (46) is sleeved on the end of the mandrel, namely the end of the sleeve head, the backing plate (46) is fixed on the end of the sleeve head (45) through a through wire (47), the through wire is screwed into the central screw hole (23), and a small fit clearance exists between the backing plate (46) and the fixed sleeve (41) so that the backing plate (46) can rotate along with the sleeve head, namely the core rod.

4. The intramedullary fixation device of claim 2, wherein a combination screw hole (48) is provided on the outer edge of the stator and the inner edge of the orifice of the outer cannula and a locking wire is installed.

5. Intramedullary fixation device for femoral fractures according to claim 2, characterized in that a pair of blind holes (49) are provided on the end face of the sleeve, which are screwed by means of a fork spanner snapping into the corresponding blind holes.

6. Intramedullary fixation device for femoral fractures according to claim 1, characterized in that the blade head (34) is externally convex and provided with a toothed profile and the end of the blade head (34) is also provided with a hook-like profile.

7. Intramedullary fixation device for femoral fractures according to claim 1, characterized in that on the outside of the threaded segment (13) is mounted a tensioning nut (14) fitted with a shim (15) approximating the curvature of the surface of the bone.

8. The intramedullary fixation device for femoral fractures according to claim 1, characterized in that 4 to 8 axial sipes (11) are provided in the front end of the outer sleeve, and blades of matching thickness are respectively installed in each axial sipe (11).

9. The intramedullary fixation device of claim 1, further comprising an intramedullary nail implanted and fixed in the femoral bone cavity, wherein the proximal end of the intramedullary nail is provided with a through side hole, the outer sleeve is fitted through the through hole in the proximal side of the intramedullary nail, and the tension nut and its spacer are supported on the side wall of the side hole of the intramedullary nail.

10. The intramedullary fixation device of claim 1, wherein the outer sleeve has a wall plate fixed to an outer end thereof, a through hole formed at a center thereof, and a small end knob extending from the through hole, the end plate having at least one pair of positioning holes eccentrically formed therein, each positioning hole having a locking member inserted therein, the tightening nut having a protrusion and a groove formed on an outer circumferential surface thereof, the locking member being simultaneously engaged with the groove formed on an outer circumferential surface of the tightening nut.