KR100399004B1 - Frame fixator and operation system thereof - Google Patents

Abstract

The present invention relates to an extracorporeal fixture and a drive system thereof, comprising: an upper ring and a lower ring, and a plurality of length adjusting means having both ends coupled to the upper ring and the circular ring; The length adjusting means includes an actuator, a moving member moved by the actuator, and a digital indicator indicating the length of the length adjusting means that changes as the moving member is moved. The extension rate and the distraction frequency can be automatically adjusted, and the length change value according to manual or automatic adjustment is displayed digitally, which facilitates the length adjustment.

Description

In vitro fixation and driving system thereof

The present invention relates to a Hexapod Ring Type Frame Fixator, which is used for fixation and bone extension of a fracture, in particular, an in vitro for automatically adjusting the elongation and elongation period of the fracture fragment during bone deformation correction and bone extension. A fixture and its drive system.

In general, typical orthopedic in vitro fixation apparatuses used for fixation of fractures, bone extension, deformation correction of bone and soft tissue, etc. include EBI method, Hoffmann method, Mono method, and Ilizarov method.

Among these, Ilizarov type extracorporeal fixation mechanism can shorten the treatment period by promoting the formation of blood vessels and bones at the fracture, and can achieve stable fixation effect by being strong against external forces such as rotational deformation force, and also to fix each deformation that may occur after surgery. It shows excellent results.

However, the Ilizarov method of the IVF fixture requires considerable effort during the procedure because the apparatus must be assembled separately according to the fracture type despite the excellence of the result of the bone deformity correction and the extension of the bone. Became.

Also, every six hours, the surgeon must manually operate the instrument to adjust the draw cycle (number of treatments) and the draw rate (stretch length), so both the surgeon and the patient are inconvenient in terms of efficiency and convenience of the procedure. There was a problem that the precision is reduced due to the error caused by.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and is applied as a general-purpose fracture and deformation treatment apparatus that can be applied regardless of fracture and deformation forms by applying the six degree of freedom parallel mechanism used in robotics or machine tools. It is an object of the present invention to provide an extracorporeal fixture having a function and a driving system thereof.

Another object of the present invention is to apply a motor driving mechanism capable of adjusting the length of the strut, and to fix the bone deformation and extend the fracture rate (Distraction Frequency) of the fracture fragments at the time of bone extension To provide a drive system.

Another object of the present invention is to attach an LCD (digital indicator) to the struts to digitally display the length change value of the struts according to manual or automatic adjustment to provide an in vitro fixture and its drive system to facilitate length adjustment have.

Still another object of the present invention is to increase the regeneration cycle of bone tissue by increasing the cycle period compared to manual operation by driving the motor using a microprocessor, it is possible to gradually stretch the soft tissue damage around the bone (Soft Tissue Damage) The present invention provides an in vitro fixation device and a driving system that reduce the use of additional drugs such as analgesics by reducing the pain felt by the patient during bone stretching.

Still another object of the present invention is to provide an in vitro fastener and its driving system which can be accurately and simply adjusted only by the operation of the computer since the drive information between the motor driving system and the computer is transmitted through an external interface.

1 is an external view of an in vitro fastener according to the present invention;

2 is an external view of a strut applied to the present invention,

3 is an internal configuration diagram of an actuator provided with a motor driving mechanism according to the present invention;

4 is a cross-sectional view taken along line AA ′ of FIG. 3;

5 is a drive system for controlling the motor drive mechanism of the in vitro stator according to the present invention,

6 is a view showing an initial screen of a computer program for calculating a length adjustment schedule of a strut applied to the present invention;

7 is a diagram showing a table of the length adjustment schedule of the struts output by the computer program for calculating the length adjustment schedule of the struts applied to the present invention;

8 is an X-ray photographing view for explaining the deformation parameter applied to the present invention,

9 is an X-ray photographing view for explaining a mounting parameter applied to the present invention,

FIG. 10 is a view for explaining mechanically a process of calculating a length adjustment schedule of a strut applied to the present invention; FIG.

11 is an X-ray photographing view for explaining a residual deformation correction mode applied to the present invention.

<Explanation of symbols for the main parts of the drawings>

10: in vitro fixture 21: top ring

22: lower ring 30: strut

32: actuator 34: threaded rod

36: nut 38: LCD

40: motor 42,44: first and second gear

46: guide member 48: potentiometer

50: motor drive device 52: control means

56 interface means 80 computer

In order to achieve the above object, the extracorporeal fixture according to the present invention includes a top ring and a bottom ring, and a plurality of length adjusting means having both ends coupled to the top ring and the circular ring; The length adjusting means includes an actuator, a moving member moved by the actuator, and a digital indicator indicating the length of the length adjusting means that changes as the moving member is moved. Silver converts rotational motion into linear motion such as struts, racks and pinions, and lead screws using threaded rods, or any mechanism that performs linear motion such as hydraulic and pneumatic cylinders and linear motors.

In addition, the drive system of the IVF fixture according to the present invention includes a top ring and a bottom ring, and a plurality of length adjusting means whose length is changed as both ends are coupled to the top ring and the circular ring and the moving member is moved. The extracorporeal fixture is characterized in that the length adjusting means is driven by a motor driving device for automatically adjusting the elongation period and elongation.

The motor driving apparatus includes control means for outputting a control signal for adjusting the elongation period and elongation of the length adjusting means, a motor driven in accordance with a control signal from the control means, and the moving member in accordance with the driving of the motor. And a length measuring means for measuring a length of the transfer member for moving the length and the length adjusting means according to the moving position of the moving member. The transmission member may use not only spur gears, but also gear elements such as helical gears and worm gears, as well as power tools such as sprocket chains and belts, and the length measuring means may be a device for measuring lengths such as potentiometers and encoders. Can be used.

In addition, the drive system of the IVF apparatus according to the present invention inputs clinical data such as frame parameters, deformation parameters, mounting parameters, etc. according to the fracture or deformation state of the patient, and draws the stretching cycle of the length adjusting means by the built-in program. A computer for calculating an elongation and transmitting it to the motor drive device; Interface means for updating data periodically or aperiodically in the IVF for data communication and data reception using the computer is further provided.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is an external view of an external fixation apparatus according to the present invention, FIG. 2 is an external view of a strut applied to the present invention, and FIG. 3 is an internal configuration diagram of an actuator provided with a motor driving mechanism according to the present invention. Is AA 'sectional drawing of FIG.

As shown in FIG. 1, the IVF 10 is provided with an upper ring 21 and a lower ring 22 at an upper side and a lower side, respectively, between the upper ring 21 and the lower ring 22. There are a plurality of (eg six) struts 30 are installed, the plurality of struts 30 is a universal joint, spherical to the upper ring 21 and the lower ring 22 It is hinged by a spherical joint or the like.

As shown in FIG. 2, each strut 30 is coupled with an actuator 32 and a nut 36 to the actuator 32 to form a threaded rod that moves in accordance with the rotation of the nut 36. Is configured to (34), on the outer peripheral surface of the actuator 32, as well as digitally display the total length (mm) of the strut 30 that changes in accordance with the movement of the rod-shaped rod 34, An LCD 38 is provided which displays the mode of operation (manual / automatic), power status (voltage) and computer connection, which is protected from the outside by a transparent window.

As shown in FIGS. 3 and 4, a motor 40 is generated in the actuator 32 to generate a driving force to move the threaded rod 34. A first gear 42 is installed on the shaft, and a second gear 44 that is engaged with the first gear 42 and moves the rod 34 having the threaded portion on one side of the first gear 42 is a nut. It is coupled to (36).

In addition, one end of the threaded rod 34 is provided with a guide member 46 that moves in conjunction with the movement of the threaded rod 34, and one side of the guide member 46 is provided. A potentiometer 48 for measuring the length of the strut 30 using a voltage value or a resistance value that changes with the movement of the guide member 46 is provided.

In addition, the motor driving device 50 for driving the motor 40 to automatically adjust the length of the strut 30 according to the length adjustment schedule of the struts input and stored from the computer 80 inside the actuator 32. And a power supply unit 60 for supplying power to the motor driving device 50 and the motor 40, and one side of the motor driving device 50 to the control signal from the motor driving device 50. Accordingly, the LCD driver 70 for driving the LCD 38 is provided.

The power supply unit 60 is a portable small battery or a battery for supplying power by an external input, and includes from a daily disposable battery to recharging by an external DC supply device to driving by a DC power source directly from the outside.

Next, a driving system for controlling the motor driving mechanism of the IVF configured as described above will be described with reference to FIG.

As shown in FIG. 5, the drive system of the IVF is configured to automatically adjust the length of the strut 30 by driving the motor 40 according to the length adjustment schedule of the strut input and stored in the computer 80. Through the transmission cable 81 by calculating the length adjustment schedule of the strut (the length of the strut length adjustment and the length of the strut at this time) according to the motor driving device 50 and the fracture state or deformation (deformation) of the patient. It is composed of a computer 80 for transmitting to the motor drive device 50, the transmission cable 81 may be connected to or disconnected from the motor drive device 50 as required by the practitioner.

The motor drive device 50 is a control means 52 for automatically adjusting the length of the strut 30 according to the length adjustment schedule of the strut input and stored in the computer 80, and the control from the control means 52 The motor driving means 54 for driving the motor 40 in response to the signal, the gears 42 and 44 for moving the rod 34 in which the thread is formed in accordance with the driving of the motor 40, and the thread The potentiometer 48 measuring the length of the strut 30 according to the movement position of the formed rod 34 and inputting it to the control means 52, and the surgeon updates the length adjustment schedule of the strut periodically or aperiodically. It consists of an interface means 56 for making.

The control means 52 is a central processing unit composed of a timer, a control device, a controller storage device, a register, an ALU, a main memory device, an interface, and the like, and is generally composed of a circuit board. One microprocessor chip, consisting of a Very Large Scale Interface (VLSI), functions as a central computing unit.

The interface means 56 is an external interface for data communication and data reception using a computer 80, and the input and output means of electrical data is used as an input window of an intermediate terminal where a surgeon can be a connection of any input means. It is a means of connecting two equipments by specifying all necessary requirements for connection or interface or connection between two different devices or circuits. That is, the connection, the interface, and the connection at the common boundary when connecting the two systems or equipment, such as the motor drive device 50 and the computer 80, IEEE-488, RS-232C and the like are used.

The computer 80 analyzes the fracture state or deformation (deformation) state of the patient by looking at the X-ray photograph, and compares it with the normal state, and then three frame parameters which are initial input values. Inputting clinical data such as six deformation parameters representing the degree of deformation, four mounting parameters representing the position of the bone with respect to the center of the upper ring 21 or the lower ring 22, etc. There is a program that automatically calculates the length adjustment schedule of the in vitro.The program performs kinematic analysis based on the clinical data entered as above to prevent damage to soft tissues or nerves around the bone. Calculate the length adjustment schedule of the struts to allow the periodic 10 to move with the proper trajectory to reach the final position.

Hereinafter, the operational effects of the IVF and the driving system configured as described above will be described.

The surgeon mounts the extracorporeal fixture 10 to the procedure patient (accidental fracture treatment or chronic malformation correction) as follows.

First, X-ray photographs (front and side) of the patient are examined to determine the fracture or deformation state due to an accidental fracture or chronic malformation, and then the diameters of the upper ring 21 and the lower ring 22 are appropriately selected. Fix it perpendicular to the fracture as shown in.

At this time, the upper ring 21 and the lower ring 22 is fixed by a wire perpendicularly to the longitudinal axis (ⓧ) of each fracture piece, respectively, so that the upper ring 21 and the lower ring 22 are parallel to each other. You will not.

Next, on the screen of the computer 80 shown in FIG. 6, the deformation correction mode (Inital Deformity Correction mode or Remaining Deformity Correction Mode) and the surgical site (for example, the tibia or ), Enter three frame parameters, six deformation parameters, and four mounting parameters using the mouse or keyboard, and then set the maximum safe elongation (Max. Safe). Enter the Distraction Rate.

Subsequently, when a simulation is performed by clicking a schedule button on the screen of the computer 80 shown in FIG. 6, the program embedded in the computer 80 gradually adjusts the length of the strut 30 so that the upper ring 21 and The length adjustment schedule of each strut (the length of the strut) so that the lower ring 22 gradually moves from the state of fracture or deformation (before the initial deformation correction) to the neutral state (after completion of the initial deformation correction). Schedule and adjustment of the length of the strut at this time) is calculated and displayed. Also, as shown in FIG. 7, the contents displayed on the screen are output as a single document and not simulated every time. You can use a document that has already been printed. At this time, the length adjustment schedule of each strut is calculated so that the elongation of the fracture pieces does not exceed the maximum safe elongation.

When the length adjustment schedule of the strut is calculated as described above, the practitioner determines the length of the six struts 30 (S1 to S6) on the initial strut length on the length adjustment schedule of the strut (e.g., S1 = 223.8, S2 = 167.7). , S3 = 199.7, S4 = 195.2, S5 = 236.2, S6 = 198.0).

When the practitioner turns the nut 36 coupled to the actuator 32 of the strut 30 to manually adjust the length of each strut 30, the actuator 32 is operated according to the rotation operation of the nut 36. While the threaded rod 34 coupled to the nut 36 is linearly moved, the guide member 46 coupled to one end of the threaded rod 34 moves in tandem.

Therefore, the length of the strut 30 through the LCD 38 by measuring the length of the strut 30 according to the movement position of the rod-shaped rod 34 in the potentiometer 48 installed on one side of the guide member 46. The digital display (eg, 130 mm) allows the surgeon to easily and accurately adjust the length of the strut 30 manually.

Subsequently, six (S1-S6) struts 30 adjusted to the initial strut length on the strut length adjustment schedule as described above were universal joints to the upper ring 21 and the lower ring 22 fixed to the patient. Hinge coupling with a spherical joint or the like is assembled as shown in FIG. 1 to complete the mounting of the extracorporeal fixture 10.

Then, after completing the mounting of the IVF 10 as described above, the actuator 32 installed in each strut 30 is connected to the computer 80 through the transmission cable 81 to calculate in the computer 80 The length adjustment schedule of each strut is input to the control means 52 through the interface means 56 of the motor drive device 50 installed in each actuator 32 and stored therein.

Subsequently, the control means 52 of the motor drive device 50 receives a control signal for adjusting the length of the strut 30 according to the length adjustment schedule of the strut input and stored through the interface means 56 as described above. Output to the drive means 54.

Accordingly, the motor driving means 54 receives a control signal output from the control means 52 to drive the motor 40, and when the motor 40 is driven, the motor coupled to the shaft of the motor 40. The first gear 42 rotates and meshes with the first gear 42 so that the second gear 44 rotates to move the threaded rod 34 coupled to the nut 36.

When the threaded rod 34 moves, the guide member 46 coupled to one end of the threaded rod 34 is interlocked to move the strut 30 according to the moving position of the threaded rod 34. ) Is measured by the potentiometer 48 and input to the control means 52.

Accordingly, the control means 52 gradually adjusts the length of the strut 30 to the neutral position while comparing the length of the strut 30 measured by the potentiometer 48 with the strut length on the length adjustment schedule of the stored strut. Treat fractures or chronic deformities.

In conclusion, according to the length adjustment schedule of the struts calculated by the computer 80, the length of the struts 30 of the IVF 10 may be automatically or gradually adjusted (automatically adjusting the elongation period and elongation of the fracture pieces). When the upper ring 21 and the lower ring 22 are parallel to each other, the fracture pieces are straight and the initial deformation correction is completed.

Meanwhile, the process of calculating the length adjustment schedule of each strut in the computer 80 will be described in more detail as follows.

The three frame parameters are composed of the diameter of the upper ring 21 and the lower ring 22 and the neutral frame height. The neutral frame height is the upper ring 21 and the lower end after the initial deformation correction. It is the distance between the rings 22, and the length of the neutral strut may be used instead of the height of the neutral frame.

The six deformation parameters are values indicating the degree of deformation, and as shown in FIG. 8, the surgeon takes an X-ray photograph (front and side) and shows an initial correspondence point (ⓐ) and a postoperative procedure. Angular (A1) and Translation (T1) and Lateral (Medial-Lateral view, ML) in the Anterior-Posterior view (AP view) with the normal point angular strain A1 and linear strain T2 in view, and angular strain A3 and linear strain T3 in Axial view.

In this case, the deformation parameters have different meanings in the initial deformation calibration mode and the residual calibration mode, respectively, and represent a starting value in the initial deformation calibration mode and a target value in the residual calibration mode.

In addition, the four mounting parameters have an X-ray photograph (front, side) and represent the position of the bone with respect to the center of the reference ring (lower ring in the tibia, upper ring in the tibia), Figure 9 As shown in Fig. 2, the degree of deviation of the normal reference point (ⓢ) from the normal reference point (ⓢ) after the procedure from the height of the reference ring (Axial view offset) (01) and the center point (ⓒ) of the reference ring on the front and side surfaces. (AP view Offset, ML view Offset) (O2, O3), and the deviation angle (starting point: strut serial number order) (Rotary Offset) 04 from the center point ⓒ of the reference ring.

As described above, when 13 clinical data including three frame parameters, six deformation parameters, and four mounting parameters are input to the computer 80, the maximum safety elongation is input, and the simulation is performed, the computer 80 The kinematic analysis in the built-in program calculates the length adjustment schedule of each strut (the time of strut length adjustment and the length of the strut length at this time).

FIG. 10 shows an example of femoral operation, in which the lower ring 22 becomes a reference ring and the upper ring 21 becomes a moving ring. In addition, the front (Anterior-Posterior view, AP view), the side (ML view), and the top (Axial view) directions are represented by x, y, and x coordinates, respectively.The center point of the calibration ring is Ou, and the center point of the reference ring is Or Represented by. In addition, an origin point was arbitrarily determined for a point where two separated bones meet.

The length of each strut progressively adjusted in FIG. The kinematic formula for calculating) is shown in Equation 1 below.

In Equation 1 Is calculated by Equation 2 below as a position vector between the center of the reference ring and the center of the calibration ring. And, in Equation 1 Is a rotation matrix between the reference ring and the calibration ring, and is calculated by Equation 6 below. In addition, Is the position vector (n = 1 .... 6) of each joint with respect to the center of the calibration ring, Is the position vector (n = 1 ... 6) of each joint with respect to the center of the reference ring.

In Equation 2 Is calculated by Equation 3 below as a position vector of an origin point with respect to the center of the reference ring, Is a position vector representing the deformation amount, and is calculated by Equation 4 below, which is a start value in the initial strain correction mode, and a target value in the residual strain correction mode. Is calculated by Equation 5 below as a position vector of the origin with respect to the center of the calibration ring.

In Equation 3, the joint height margin is the height of the joint provided in the IVF.

In Equation 4 , , Are the linear transformation of the front view (AP view), the linear transformation of the side view (ML view), and the linear transformation of the upper surface (Axial view), respectively.

In Equation 6, , , Are respectively Angular of the AP view, Angular of the ML view, Angular of the Axial view, Is a rotary frame offset.

At this time, the calibration period is determined by dividing the initial deformation state (preoperative state) to the final deformation state (state after completion of the procedure) by the maximum safety elongation rate (r). Using Equation 8 , Determine.

(i = 0, 1, 2 ....... maximum number of calibrations)

Meanwhile, as shown in FIG. 11, when the upper ring 21 and the lower ring 22 are parallel to each other, when the fracture fragments are not straight, the initial deformation correction is performed. do.

In other words, in the Remaining Deformity Correction Mode, the surgeon looks at the X-ray photograph of the patient and shows three frame parameters, six deformation parameters, and four mounting parameters. Input each Mounting Parameter). Then, when the maximum safety elongation rate (Max. Safe Distraction Rate) is input and the simulation is performed, the program embedded in the computer 80 gradually adjusts the length of the strut 30 so that the upper ring 21 in a neutral state is provided. The length adjustment schedules of the respective struts for the six (S1-S6) struts 30 are calculated to move the lower ring 22 and the lower ring 22 to the deformation state for correcting the malformed state according to the schedule. The schedule is reversed from the schedule output in the initial strain calibration mode.

At this time, since the residual deformation correction is performed after the initial deformation correction, since three frame parameters and four mounting parameters are the same as before, only six deformation parameters may be input and used.

As described above, the length adjustment schedule of the strut calculated by the computer 80 is retransmitted to the control means 52 of the motor drive device 50 via the interface means 56, and the motor drive means 54 controls the control means. The control signal output from the 52 is input to drive the motor 40 to adjust the upper ring 21 and the lower ring 22 fixed in parallel to the deformed state as shown in FIG. The state will be corrected.

At the same time, the LCD driver 70 displays the length of the strut 30 digitally through the LCD 38 according to the control signal from the control means 52, so that the length of the strut 30 can be easily adjusted by the patient or the patient. Displays the operating mode (automatic) status while you confirm it.

As such, the six struts 30 (S1 to S6) hinged to the upper ring 21 and the lower ring 22 of the IVF 10 may be provided with a motor driving device installed inside each actuator 32. 50) is automatically adjusted according to the schedule, so that both the surgeon and the patient can be treated conveniently.

In addition, the draw cycle can be increased as desired, and the width of the draw rate is finely adjusted by increasing the draw cycle, thereby increasing the precision compared to manual operation.

On the other hand, in one embodiment of the present invention by using the strut 30 using a threaded rod 34 to adjust the elongation period and elongation, but described as an example, the present invention is not limited to this rack and pinion, lead Of course, the same objects and effects as those of the present invention can be achieved by using a screw, a hydraulic / pneumatic cylinder, a linear motor, or the like.

In addition, in one embodiment of the present invention, the threaded rod 34 is moved using a spur gear composed of the first and second gears 42 and 44 as an example, but the present invention is not limited thereto. Other types of gears and transmission mechanisms such as helical gears, worm gears, sprocket-chain drives, belt drives, and the like can also be used to achieve the same objects and effects as the present invention.

In addition, in one embodiment of the present invention has been described taking an example of measuring the length of the strut 30 using the potentiometer 48, the present invention is not limited to this, the same purpose and effect as the present invention using an encoder Of course it can be achieved.

As described above, according to the in vitro fastener and the drive system according to the present invention, by applying the six degree of freedom parallel mechanism used in robotics or machine tools, universal fracture and deformation treatment that can be applied regardless of the fracture and deformation form It has the function as a mechanism, and by applying a motor driving mechanism that can adjust the length of the strut, it is possible to automatically adjust the distraction rate and the distraction frequency of the fracture fragment during bone deformation correction and bone extension.

In addition, the LCD is attached to the struts to digitally display the length change value of the struts according to manual or automatic adjustment, which facilitates the length adjustment and increases the draw cycle compared to manual operation by operating the motor using a microprocessor. Promote bone regeneration and allow gradual stretching to minimize soft tissue damage around the bone while reducing pain experienced by the patient during bone stretching, thus reducing the use of additional drugs such as analgesics. have.

In addition, since the drive information is transferred between the motor drive system and the computer through an external interface, accurate and simple adjustment can be made simply by operating the computer, and the drive data for the treatment period can be stored in the controller to operate the in vitro fixture independently. Even when medical treatment is required, the database can be used to systematically manage the patient's treatment process.

Claims (5)

Top and bottom rings, It is provided with a plurality of length adjusting means is coupled to both ends of the upper ring and the circular ring; And the length adjusting means includes an actuator, a moving member moved by the actuator, and a digital indicator indicating the length of the length adjusting means that changes as the moving member is moved. In the in vitro fastener comprising a top ring and a bottom ring, and a plurality of length adjusting means that is coupled to both ends of the top ring and the circular ring and the length thereof changes as the moving member is moved, And the length adjusting means is driven by a motor driving device that automatically adjusts the elongation period and elongation. The method of claim 2, The motor drive apparatus includes control means for outputting a control signal for adjusting the elongation period and elongation of the length adjusting means, a motor driven in accordance with a control signal from the control means, and the movement in accordance with the driving of the motor. And a length measuring means for measuring the length of the length adjusting means according to the moving position of the moving member and the transfer member for moving the member. The method of claim 3, wherein When the clinical data such as frame parameters, deformation parameters, mounting parameters, etc. are input according to the fracture or deformation state of the patient, a computer for calculating the elongation period and elongation of the length adjusting means by the built-in program and adding them to the motor driving device is added. A drive system for an extracorporeal fixture characterized in that it is provided with. The method of claim 4, wherein And an interface means for updating data periodically or aperiodically to said IVF for data communication and data reception using said computer.