CN111603233A - A kind of bone lengthening intramedullary nail device - Google Patents

Abstract

The invention discloses a bone lengthening intramedullary nail device, which relates to the technical field of bone lengthening and comprises an intramedullary nail and an external stator; the intramedullary nail comprises a near-end nail body and a far-end nail body, wherein the near-end nail body is of a hollow structure with an opening at one end, a screw rod is rotatably arranged in the near-end nail body, a rotor is fixedly sleeved at one end of the screw rod, one end of the far-end nail body is slidably arranged in the near-end nail body, and one end of the far-end nail body, which is positioned in the near-end nail body, is in threaded connection with the screw; the rotor is uniformly provided with a plurality of permanent magnets at the circumference, the magnetic poles of one ends of two adjacent permanent magnets close to the rotor are opposite, the external stator is provided with a three-phase winding coil, and the external stator can be coupled with the rotor after being electrified to drive the rotor to rotate. The intramedullary nail device for bone lengthening can drive the bone to stretch in the inner part, can relieve the pain of a patient compared with a stretching mode of external machinery, is easy to operate and control, and can effectively avoid secondary damage to the patient during the bone lengthening.

Description

A kind of bone lengthening intramedullary nail device

technical field

The invention relates to the technical field of bone lengthening, in particular to a bone lengthening intramedullary nail device.

Background technique

Definition of bone lengthening: that is, distraction osteogenesis, that is, the bone is cut open, the soft tissue and blood supply are preserved, the two ends are fixed with a special traction device, and the tensile force is gradually applied to slowly stretch the bone segment, constantly stimulating the body tissue. , to stimulate the regeneration potential of human tissue, so that new bone can be formed in the osteotomy space to achieve the purpose of bone regeneration. In the prior art, for patients with uneven legs caused by bone defects, the medical method of extending the bones by external mechanical stretching is used for treatment. In this method, since the traction device is installed outside the body, it is difficult to accurately control the stretching direction, stretching force and stretching amount, etc., which will bring great pain to the patient during treatment; at the same time, it is difficult for doctors to control the operation, and there are certain medical risks.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a bone lengthening intramedullary nail device, which drives the intramedullary nail inside the bone to stretch the bone. Compared with the external mechanical stretching method, it can reduce the pain of the patient, At the same time, it is easy to operate and control, which can effectively avoid the secondary injury to the patient during the period of bone lengthening.

The purpose of this invention is to realize through the following technical solutions:

A bone-lengthening intramedullary nail device, comprising an intramedullary nail and an external stator;

The intramedullary nail includes a proximal nail body and a distal nail body, the proximal nail body is a hollow structure with one end open, a screw rod is rotatably arranged in the proximal nail body, and one end of the screw rod is fixedly sleeved There is a rotor, one end of the distal nail body is slidably arranged in the proximal nail body, and one end of the distal nail body located in the proximal nail body is connected with the screw rod through threads;

The rotor is provided with a number of permanent magnets evenly distributed around the circumference. The magnetic poles of two adjacent permanent magnets close to one end of the rotor are opposite. The outer stator is provided with three-phase winding coils. It is coupled with the rotor to drive the rotor to rotate.

Further, it also includes a frequency conversion governor, which is electrically connected to the three-phase winding coil of the external stator.

Further, the proximal nail body includes a proximal locking nail tail, a rotor shell and a proximal nail body shell,

The proximal nail tail includes a connecting seat, a locking nail seat a and a locking cap arranged in sequence, a locking nail a is laterally inserted into the locking nail seat a, and one end of the connecting seat is fixedly provided with a connection the screw, the locking nail seat a and the locking cap are all threadedly connected with the connecting screw;

The rotor shell includes a lower shell seat and an upper shell seat, one end of the lower shell seat and one end of the upper shell seat are connected by threads, and one end of the upper shell seat away from the lower shell seat and the connecting seat away from the lock One end of the screw seat a is fixedly connected by bolts;

One end of the proximal nail body shell and the end of the lower shell seat away from the upper shell seat are connected by bolts, the screw rod is rotatably arranged in the proximal nail body shell, and the rotor is arranged at the inside the rotor housing.

Further, one end of the screw rod is fixedly connected with a guide column, the other end of the guide column is fixedly connected with a connecting shaft, and the rotor is fixedly sleeved on the connecting shaft,

The guide column is matched with the inner wall of the proximal nail body shell, and one end of the proximal nail body shell, the lower shell seat, the upper shell seat and the connecting shaft are all connected by bearings.

Further, the distal nail body includes a sliding column, the side wall of the sliding column is provided with a sliding rail, the inner wall of the proximal nail body shell is processed with a sliding groove, and one end of the sliding column is slidably arranged. In the proximal nail body shell, the sliding rail is adapted to the sliding groove;

The other end of the sliding column is fixedly provided with a connecting screw b, and the connecting screw b is sequentially connected with a locking nail seat b and a nail head through threads, and a locking nail b is laterally inserted into the locking nail seat b. .

The beneficial effects of the present invention are:

The bone-extending intramedullary nail device includes an intramedullary nail and an external stator. The intramedullary nail includes a proximal nail body and a distal nail body. The proximal nail body is rotatably provided with a screw rod, and one end of the screw rod is fixedly sleeved with a rotor. One end of the distal nail body is slidably arranged in the proximal nail body and is connected with the screw rod through threads. A three-phase winding coil is arranged on the outer stator, and a rotating magnetic field is generated in the outer stator when it is energized, which can drive the rotor to rotate, thereby driving the distal nail body to translate to realize the pulling process of strand extension. In the above stretching process, the stretching force and the stretching speed are determined by the rotation speed of the rotor, and the operation of the rotor is controlled by the size and frequency of the energized current in the external stator. The control process is simple, convenient and accurate. The rotating rotor and the screw part are set inside the internal nail without contact with the diseased body. During stretching, the stretching direction is limited by the structure of the intramedullary nail, which is stable and controllable. In addition, the above-mentioned stretching force and stretching speed can be accurately controlled. When using it for treatment, it can effectively relieve the pain of the patient and avoid the secondary injury caused to the patient during the bone lengthening.

Description of drawings

FIG. 1 is a schematic diagram of the overall structure of a bone lengthening intramedullary nail device according to the present invention;

FIG. 2 is a schematic diagram of the split structure of an intramedullary nail in a bone-extending intramedullary nail device of the present invention;

FIG. 3 is a schematic diagram of the coupling structure of the external stator and the rotor in a bone lengthening intramedullary nail device of the present invention;

FIG. 4 is a schematic diagram of the disassembled structure of the proximal nail body in a bone lengthening intramedullary nail device of the present invention;

FIG. 5 is a schematic view of the disassembled structure of the connecting part between the proximal nail body and the distal nail body in a bone lengthening intramedullary nail device of the present invention;

FIG. 6 is a schematic view of the disassembled structure of the distal nail body in a bone lengthening intramedullary nail device of the present invention.

Detailed ways

The technical solutions of the present invention are further described in detail below with reference to the accompanying drawings, but the protection scope of the present invention is not limited to the following.

As shown in FIG. 1 , a bone-lengthening intramedullary nail device includes an intramedullary nail and an external stator 10 .

As shown in FIG. 2, the intramedullary nail includes a proximal nail body 30 and a distal nail body 20. The proximal nail body 30 has a hollow structure with one end open. A screw rod 42 is rotatably arranged in the proximal nail body 30. The screw rod 42 A rotor 41 is fixedly sleeved at one end of the distal nail body 20 , and one end of the distal nail body 20 is slidably disposed in the proximal nail body 30 . Because the distal nail body 20 can only slide in the proximal nail body 30, its rotational freedom following the rotation of the screw rod 42 is limited, and the two form a set of screw transmission mechanism. When the screw rod 42 rotates, the distal nail body can be rotated Body 20 moves axially along proximal staple body 30 .

The above-mentioned rotor 41 is provided with several permanent magnets evenly distributed around the circumference, and the magnetic poles of two adjacent permanent magnets close to one end of the rotor are opposite; The structure is shown in Figure 3, and the principle is similar to that of a permanent magnet synchronous motor. When the three-phase winding coils on the outer stator 10 are supplied with alternating current, a rotating magnetic field will be generated in the outer stator 10, while the permanent magnets fixedly installed on the rotor 41 will generate a relatively fixed magnetic field, which attracts and repels according to the same-sex attraction and opposite-sex repulsion. According to the principle, the rotor 41 will start to rotate in the rotating magnetic field, thereby driving the above-mentioned axial movement of the distal nail body 20 .

During specific implementation, due to the small size of the rotor 41 itself, in order to ensure its convenient manufacture and sensitive rotation, four permanent magnets can be set on the inner rotor 41, and the outer sides thereof are N-level, S-level, N-level, and S-level in sequence. Under the action of the rotating magnetic field generated by the outer stator 10, the outer magnetic poles of each permanent magnet are subjected to a force of attraction or repulsion, thereby driving the rotor 41 to rotate. The three-phase winding coils on the outer stator 10 can be set to be reversely wound on opposite coils, that is, the current flows inward on one side and the current flows outward on the other side. generate a magnetic field. Due to the different phases when each phase winding is energized, the magnitude of the magnetic field generated by each phase is different. For the magnetic field formed in the entire outer stator 10, the combined magnetic field direction will rotate, so as to realize the above process of driving the rotor 41 to rotate.

Further, the bone-extending intramedullary nail device further includes a frequency conversion speed regulator 11 , and the frequency conversion speed regulator 11 is electrically connected to the three-phase winding coils of the external stator 10 . When in use, the variable frequency governor 11 is connected to the variable frequency power supply, and the magnitude and frequency of the current can be adjusted by the variable frequency governor 11, and the strength and rotation speed of the rotating magnetic field in the external stator 10 can be adjusted accordingly. When applying, it is necessary to formulate a medical plan in advance, and select an appropriate intramedullary nail for femoral lengthening: for example, during the stretching process, if you stretch 1mm a day and divide it into three stretches, stretch 0.2mm-0.3mm each time; The pitch of the screw 42 can convert the length of each stretch into the number of turns required to rotate the thread. At the same time, the force required for one rotation of the thread, the strength of the external rotating magnetic field, and the duration of energization of the outer stator were determined by simulating the environment. Then use these data as the standard to actually operate. When used clinically, the above intramedullary nail is placed in the medullary cavity of the patient's bone, and the two ends of the intramedullary nail are respectively fixed to the bone by locking nails. In this position, the external stator 10 outside the body is set at a position coupled with the rotor 41, and then the power-on control is performed according to the parameters measured by the above simulation, and the rotor 41 is driven to rotate by the rotating magnetic field in the external stator 10, so that the distal nail body is rotated. 20 Moving axially, the proximal end and the distal end of the intramedullary nail move away from each other, so as to realize the above-mentioned stretching process. When stretched to a specified length, the power supply of the three-phase winding coils on the outer stator 10 is cut off, the rotating magnetic field in it disappears, the rotor 41 stops rotating, and the stretching process is stopped.

In the above setting, the rotation speed of the rotor 41 is precisely controlled by the frequency converter 11, and its operation is simple and convenient; the intramedullary nail is arranged in the bone marrow cavity, and the rotor 41 is internally driven to provide power, and there is no external mechanical stretching mechanism. The rotating rotor 41 and the screw 42 are both located inside the intramedullary nail, which is not in contact with the patient. At the same time, the elongation direction of the intramedullary nail is stable and controllable. Pain and avoid secondary injury to the patient during bone lengthening.

In a specific implementation, as shown in FIGS. 4 to 6 , the proximal nail body 30 includes a proximal locking nail tail, a rotor housing and a proximal nail body housing 37 . The proximal nail tail includes a connecting seat 34, a locking nail seat a32 and a locking cap 31 arranged in sequence, a locking nail a33 is inserted laterally on the locking nail seat a32, and one end of the connecting seat 34 is fixedly provided with a connecting screw, and the locking Both the screw seat a32 and the locking cap 31 are threadedly connected with the connecting screw. The locking nail a33 is used for positioning and fixing the proximal nail body 30 and the bone. After the locking seat a32 is connected with the connecting screw, it can be tightened by the locking cap 31, so that the overall connection structure is stable. The rotor shell includes a lower shell seat 36 and an upper shell seat 35, one end of the lower shell seat 36 and one end of the upper shell seat 35 are connected by screws, and one end of the upper shell seat 35 away from the lower shell seat 36 and the connecting seat 34 away from the locking nail seat One end of a32 is connected by bolts. One end of the proximal nail body shell 37 is connected with the end of the lower shell seat 36 away from the upper shell seat 35 by bolts. Because before each application, in order to ensure the reliability of the stretching action, it is necessary to measure the lifespan of the permanent magnets on the rotor 41 to verify their magnetic properties. Therefore, the above-mentioned split structure of the proximal nail body 30 is adopted, and each part is connected by threads or bolts, so that it can be quickly disassembled and assembled, which is good for use.

Further, one end of the screw rod 42 is fixedly connected with a guide column 43 , the other end of the guide column 43 is fixedly connected with a connecting shaft 44 , and the rotor 41 is fixedly sleeved on the connecting shaft 44 . One end of the proximal nail body shell 37, the lower shell seat 36 and the upper shell seat 35 and the connecting shaft 44 are all connected through the bearing 45, and the rotation process of the screw 42 is smooth; It is adapted to be limited and supported by the inner wall of the proximal nail body shell 37 during rotation, which is beneficial to the stability of the rotation process.

Further, the distal nail body 20 includes a sliding column 21, the side wall of the sliding column 21 is provided with a sliding rail, the inner wall of the proximal nail body shell 37 is processed with a sliding groove, and one end of the sliding column 21 is slidably arranged at the proximal end. In the nail body shell 37, the slide rail is matched with the chute; the other end of the slide column 21 is fixedly provided with a connecting screw b22. A locking nail b24 is laterally inserted into the seat b23. Through the adaptation of the sliding rail and the sliding groove, the sliding of the sliding column 21 plays a guiding and guiding role, so that it can move in a designated direction when the screw rod 42 rotates, and the pulling direction is ensured.

The foregoing are only preferred embodiments of the present invention, and it should be understood that the present invention is not limited to the forms disclosed herein, and should not be construed as an exclusion of other embodiments, but may be used in various other combinations, modifications, and environments, and Modifications can be made within the scope of the concepts described herein, from the above teachings or from skill or knowledge in the relevant field. However, modifications and changes made by those skilled in the art do not depart from the spirit and scope of the present invention, and should all fall within the protection scope of the appended claims of the present invention.

Claims (5)

1. An intramedullary nail device for bone lengthening, characterized in that it comprises an intramedullary nail and an external stator (10); The intramedullary nail includes a proximal nail body (30) and a distal nail body (20), the proximal nail body (30) is a hollow structure with one end open, and the proximal nail body (30) is rotatable inside is provided with a screw (42), one end of the screw (42) is fixedly sleeved with a rotor (41), and one end of the distal nail body (20) is slidably arranged on the proximal nail body (30) Inside, one end of the distal nail body (20) located in the proximal nail body (30) is connected with the screw rod (42) through threads; The rotor (41) is provided with a number of permanent magnets evenly distributed around the circumference, and the magnetic poles of two adjacent permanent magnets close to one end of the rotor are opposite, and the outer stator (10) is provided with three-phase winding coils, so After the external stator (10) is energized, it can be coupled with the rotor (41) to drive the rotor (41) to rotate. 2. An intramedullary nail device for bone lengthening according to claim 1, characterized in that it further comprises a frequency converter (11), the frequency converter (11) being connected to the external stator (10) The three-phase winding coils are electrically connected. 3. An intramedullary nail device according to claim 2, characterized in that the proximal nail body (30) comprises a proximal locking nail tail, a trochanter shell and a proximal nail body shell (37) , The proximal nail tail includes a connecting seat (34), a locking nail seat a (32) and a locking cap (31) arranged in sequence, and a locking nail is laterally inserted into the locking nail seat a (32). a (33), one end of the connecting seat (34) is fixedly provided with a connecting screw, and the locking nail seat a (32) and the locking cap (31) are both threadedly connected with the connecting screw; The rotor housing includes a lower housing seat (36) and an upper housing seat (35), one end of the lower housing seat (36) and one end of the upper housing seat (35) are connected by threads, and the upper housing seat (35) The end away from the lower housing seat (36) and the end of the connecting seat (34) away from the locking nail seat a (32) are fixedly connected by bolts; One end of the proximal nail body shell (37) and the end of the lower shell seat (36) away from the upper shell seat (35) are connected by bolts, and the screw rod (42) is rotatably arranged at the proximal end. Inside the end nail body casing (37), the rotor (41) is arranged in the rotor casing. The bone lengthening intramedullary nail device according to claim 3, wherein one end of the screw rod (42) is fixedly connected with a guide column (43), and the other end of the guide column (43) is fixed A connecting shaft (44) is connected, and the rotor (41) is fixedly sleeved on the connecting shaft (44), The guide post (43) is adapted to the inner wall of the proximal nail body shell (37), one end of the proximal nail body shell (37), the lower shell seat (36) and the upper shell Both the seat (35) and the connecting shaft (44) are connected through a bearing (45). 5. An intramedullary nail device for bone lengthening according to claim 3, characterized in that, the distal nail body (20) comprises a sliding column (21), and a side wall of the sliding column (21) is provided with There are sliding rails, the inner wall of the proximal nail body shell (37) is processed with a sliding groove, and one end of the sliding column (21) is slidably arranged in the proximal nail body shell (37), and the sliding The rail is matched with the chute; The other end of the sliding column (21) is fixedly provided with a connecting screw b (22), and the connecting screw b (22) is sequentially connected with a locking nail seat b (23) and a nail head (25) through threads, so A locking nail b (24) is laterally inserted into the locking nail base b (23).

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