System for controlling the process of distraction osteosynthesis

Abstract

Claimed is a system for controlling distraction osteosynthesis in an automated external fixation apparatus on the basis of a reciprocal relationship between the distraction rate and the distraction forces. A control processing unit sends commands to movement assemblies according to a set treatment plan, records in a memory the progress of distraction over time in the form of the distraction force on each movement assembly, received from force sensors, and shows the progress of distraction in graph form on a display. The control unit generates a graph of the change in the distraction forces over time, determines the tangent of the angle between a tangent to a measuring point at a given moment of time and the abscissa axis and, by comparing the angle of inclination with set threshold values, generates control commands for the movement assemblies in accordance with an optimal distraction rate set by an algorithm. In the apparatus, this provides for control of the process of osteosynthesis in connection with the distraction forces.

Description

CONTROL SYSTEM FOR THE PROCESS OF DISTRACTION OSTEOSYNTHESIS

[0001] The technical solution relates to medical equipment, in particular to external skeletal fixation devices (hereinafter also referred to as "device") with electromechanical drives. It is used in traumatology and orthopedics for automatic dosed movement of bone fragments.

[0002] It is used as a system that controls and regulates the optimal speed of elongation of a limb segment through movement units in external fixation devices. The invention provides the possibility of highly fractional round-the-clock spatial movement of bone fragments in automatic control modes of the device.

[0003] From the existing level of technology, an automated spatial frame (orthopedic device) and automated spacers used with it, a system and a method for treating fractures are known [1].

[0004] The system [1] comprises a plurality of automatic columns for extending and retracting in response to one or more electrical signals. A control unit electrically connected to one or more of the plurality of automatic columns, a control unit for supplying one or more electrical signals to the plurality of automatic columns. A power source for supplying the plurality of automatic columns. A computing device that carries out the control commands. The automated space frame can be arranged and configured to determine when it is appropriate to dismantle the frame, based on, for example, data from measurements of the force on the strut obtained from load cells or strain gauges. Alternatively, the linear mechanical load of the column can be determined indirectly through the motor current, the distance traveled from the rotary encoder, and the energy supplied during this movement, as a function of the change in voltage on the capacitor.In use, wireless intelligent automated racks are arranged and configured to receive and transmit data over a wireless network, for example, using an external computing system, such as, for example, an application running on a mobile device. In one embodiment, a wireless automated rack includes a main body, a power source, an electronic control circuit, a motor electrically connected to the power source, wherein the motor and the power source are located inside the main body, a transmission connected to the motor output, and a rod (for example, a threaded rod, a diverter rod, a lead screw, or the like) connected to the transmission.The stand may also include a printed circuit board ("PCB") located inside the main body, wherein the PCB is arranged and configured to turn on and off the motor when the stand rod (e.g., a threaded rod, a retractor rod, a lead screw, or the like) reaches a certain position. In addition, the stand may include a rotary position sensor and a linear position sensor electrically connected to the printed circuit board. Moreover, the stand may include self-diagnostic / condition monitoring capabilities.In one embodiment, the system includes an external fixture including a plurality of wireless automated stands, a sensor located on the external fixture to provide identification of the stand and a controller, the controller includes a wireless communication module, a memory and a processor for sending or receiving a treatment plan, wherein the controller interacts with the stands to command the stands to follow the treatment plan. The stand may also include a printed circuit board located inside the main body, the printed circuit board includes a voltage regulator, a transformer, an ammeter, a wireless communication module, a load sensor and an accelerometer, a microcontroller and a memory, wherein the printed circuit board turns on and off the motor when the load sensor reaches a certain value. In addition, the stand may include a rotational position sensor and a linear position sensor electrically connected to the printed circuit board.for example, a force sensor 230 for monitoring stresses and loads through the bone gap and / or soft tissues (muscles, connecting cartilage or peripheral sensory nerves), a sensorimotor support 232, etc.

[0005] The platform may include a micro-USB connector located near each of the hinges for connection to the automated stand, along with at least one additional micro-USB connector for connection to the main control unit. The wireless communication interface may be, for example, a Bluetooth transceiver for communication with the external computing system 510, although the wireless communication interface may take any other form, such as, for example, Wi-Fi, RF, infrared or any other suitable communication method. Alternatively and / or in addition, the main control unit 300 may include a USB port for receiving a USB memory stick for exchanging data with the external computing system 510. The main control unit can transmit strut data back to the patient or surgeon through, for example, an external computing system, such as a mobile application running on a smartphone, tablet, etc., to provide regular updates on the progress of the treatment plan via Bluetooth, RF, infrared, Wi-Fi or any other suitable communication method that provides bidirectional communication between the main control unit and the mobile application. An example of the components of each automated rack includes: an embedded microcontroller; a regulator, an input capacitor; a motor drive; and a current sensor with a current shunt monitor. In the illustrated embodiment, the microcontroller 1061 may have part number ATSAMD11D14A-UU from Microchip Technology Inc., size: 2.43 mm x 1.93 mm, with 16 KB of flash memory and 4 KB of volatile memory; the capacitor may have part number C3216X5R1E476M160AC, available from TDK, size: 11 mm. 2 ; the regulator may have a part number LMZM23601V3SILR from Texas instruments, size: 19 mm 2 ; the input capacitor may be part number C2012X5R1V106K085AC from TDK, size: 7mm 2; the motor driver may be part number H-Bridge Motor Driver DRV8876 from Texas Instruments, size 3.0 x 3.0 mm 2; and the current shunt monitor may have a part number INA138 from Texas Instruments. The control unit is configured to receive treatment plan data that can be run in applications that work with a dynamic link library (DLL), such as LabVIEW, Visual Basic or other C / C++ development environments. The control unit 1030 may also include instructions for an embedded algorithm that converts data from a text file (e.g., JSON, XML and YAML) correction treatment plan into a format that can be used to individually control the length of the automated racks 1060. In this way, position control of the “synchronized” automated racks 1060 is provided. The control unit 1030 may also be arranged and configured to send commands, instructions, signals, etc. to each of the automated racks 1060 (e.g., to each of the embedded microcontrollers 1061) via, for example, a serial cable connection.

[0006] The disadvantages of the specified analogue [1] are as follows. The general principles of constructing a control system for automated platforms and transmitting data from them to a doctor are outlined. The methods for measuring the force on automated racks are also described in general terms based on known measurement methods without reference to specific device designs, which does not allow us to judge their applicability in small-sized drive devices. In addition, methods for measuring the force using a charging capacitor or by the current of an electric motor are unacceptable due to their low measurement accuracy. The method for controlling the process of distraction osteosynthesis is not disclosed, and the level at which the load sensor achieves the required switching on and off is not defined. The control process for continuously increasing distraction forces is not defined.

[0007] The “System for monitoring distraction efforts in the process of automated limb lengthening” is well known [Blynsky F.Yu., Sul'din M.P. “System for monitoring distraction efforts in the process of automated limb lengthening” / Vectors of well-being: economy and society. 2013. No. 3 (9). URL: https: / cyberleninka.ru / article / n / sistema-kontrolya-distraktsionnyh-usiliy-v-protsesse-avtomatizirovannogo-udlineniya-konechnosti ].

[0008] The control system contains a module for measuring distraction forces using a bridge connection of strain gauge sensors and a basic diagram of the module; an application with an interface for visualizing distraction forces has been created.

[0009] The disadvantages of this analog are as follows. The method for measuring the force applied to the limb is calculated using two unknown variables:

[0010] S – the cross-sectional area of ​​the elongated segment of bone tissue, which is practically unknown and requires measurement by radiography, and can also constantly change;

[0011] K is the elastic modulus of bone tissue, which is also unknown for the newly formed bone regenerate, the morphological data of which change during distraction osteosynthesis.

[0012] Thus, the proposed method of measuring force is practically impossible to implement without additional measurements for which the equipment has not been developed.

[0013] The system proposed to introduce a critical level of distraction forces of 60 kgf, exceeding which requires the doctor to reduce the distraction rate and, conversely, if the tension is below the required level, to increase the elongation rate.

[0014] This idea of ​​the tissue regeneration process is fundamentally wrong. The fact is that initially distraction efforts are only a reflection of the resistance to stretching on the part of soft tissues (skin, fascia, muscles) and do not exceed 25 kgf, and everything above this level is associated with the resistance of newly formed bone tissue (distraction bone regenerate), which has its own morphological features. Therefore, if a doctor, having discovered that distraction efforts have exceeded the critical level, begins to reduce the distraction rate, as recommended by the authors of the article, he will get a complication in the form of premature consolidation, will not complete the lengthening and will not solve the problem. And, conversely, if a doctor begins to maintain a low level of distraction efforts by increasing the distraction rate, he may get a complication in the form of delayed consolidation up to pseudoarthrosis and a defect in the bone being lengthened.The absence of subsequent clinical publications indicates that the direction of research was chosen incorrectly and the proposal is fundamentally unviable.

[0015] A transosseous automated distraction device and an automatic movement unit are known [2], containing supports connected to each other by automatic movement units (up to 6 pieces), each of which includes a gear motor with a controller, a longitudinal force sensor of the lead screw, electrically connected to the controller.

[0016] The device [2] contains a base unit designed to accommodate a power source and communication elements with external data processing devices (personal computer, smartphone, etc.). The base unit and controller are designed to automatically control the mechanisms according to a pre-compiled program. The control board with the controller is electrically connected to the base control unit, designed with the ability to enter a treatment program expressed through the dynamics of distraction efforts and displayed on a smartphone, tablet or personal computer.

[0017] The device [2] has an intelligent feedback with the distraction force control system in the process of automated limb lengthening. The control and movement system is formed on the principle of feedback when monitoring distraction forces arising in the device (in total from all movement nodes). The doctor analyzes the limb lengthening process by the dynamics of the total distraction forces visually via the interface and has the ability to change the distraction rate on each distraction rod of movement from 0.5 to 3.0 mm / day. An additional means of control is periodic radiography of the distraction regenerate. During a normal process, a smooth increase in distraction forces from 0 to 600 N is observed and under these conditions the doctor does not change the distraction rate and rhythm (1 mm / day).

[0018] With a reduced process of reparative regeneration of bone tissue, the level of distraction forces usually does not exceed 200 - 250 N and the doctor sets the distraction rate at 0.5 mm / day.

[0019] With increased reparative regeneration of bone tissue (risk of premature consolidation of bone fragments), a sharp increase in the level of distraction forces (above 600 N) is observed, and the doctor changes the distraction rate, increasing it to 2 and even 3 mm / day.

[0020] The disadvantages of the indicated analogue [2] are as follows. The control unit does not allow independent control and analysis of the lengthening process in real time. The control unit does not analyze the course of distraction over time and therefore cannot independently control the lengthening mode depending on the data obtained during the measurement process, reflecting the dynamics of changes in distraction forces over time.

[0021] The problems of analogs are as follows. In the automated transosseous compression-distraction device, control of the process of distraction osteosynthesis based on feedback from distraction efforts is not ensured.

[0022] The technical result consists in ensuring control of the process of distraction osteosynthesis based on feedback with distraction forces in an automated transosseous compression-distraction apparatus.

[0023] The technical result is achieved in that the control system for the process of distraction osteosynthesis based on feedback from the distraction forces of the transosseous compression-distraction apparatus with automatic movement units, containing a processor control unit that sends commands to the movement units in accordance with the treatment program specified by the doctor and records in its memory the course of distraction over time in the form of a distraction force at each movement unit, coming from the force sensor of the unit, and reflecting the course of distraction in the form of a graph on the display of a personal computer (for example, a smartphone), wherein the control unit is designed with the ability to generate a graph of the change in distraction forces over time, determine the tangent of the angle of the tangent of the measurement point at a given time to the abscissa line and, comparing the angle of inclination with the specified limit values, generate control commands to the movement units in accordance with the specified distraction rate algorithm.

[0024] A method for controlling the process of distraction osteosynthesis based on feedback with distraction forces in an automated transosseous compression-distraction apparatus, in which, during distraction, changes in distraction forces over time are recorded in the control unit, the tangent of the angle of the tangent at the measurement point to the abscissa axis is determined, control commands are generated for the movement nodes in accordance with the treatment program specified by the doctor and the specified limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction forces, while the time is measured and recorded at the moment of force measurement, and the nodal points of the curve are also recorded for automatic change of the tempo and rhythm of distraction.

[0025] Feedback of movement with distraction efforts has been introduced into the control system of the distraction osteosynthesis process in the automated transosseous compression-distraction apparatus, based on the analysis of force measurement data during a specified real time. At the same time, the control program is based on the clinically established dependence of the required distraction rate on individual sections of the typical distraction curve.

[0026] It has been previously proven that the level of distraction efforts, their dynamics, and treatment time are influenced by such factors as the etiology of the disease, the amount of shortening, soft tissue atrophy, muscle strength and range of motion of adjacent joints, and the amount of scar tissue from previous surgeries. The choice of the optimal distraction rate is based on taking into account all the indicators. The uniformity of the dynamics of distraction efforts during limb lengthening has been proven. This confirms the presence of general patterns in the process of distraction osteosynthesis. However, the level of efforts varies significantly, with the highest level differing in congenital limb shortening and in shortening after poliomyelitis. The latter complicates the use of the absolute value of distraction efforts in real time to control the lengthening process. It is more realistic to give a uniform description of the slope of the curve, and the slope angle itself does not characterize the process itself.Here the tangent of the angle (tg α) between the tangent to the curve and the abscissa axis can be used to formulate the equation of a straight line on the coordinate plane (y=kx+b).

[0027] The number k= tgα is called the angular coefficient of the line. The geometric meaning of the derivative is determined through this angle. The value of the derivative of the function at the desired point is numerically equal to the tangent of the angle of inclination of the tangent to the function at this point.

[0028] What is new is that in the system and method for controlling the process of distraction osteosynthesis based on feedback with distraction efforts in an automated transosseous compression-distraction apparatus, during distraction, changes in distraction efforts over time are recorded in the control unit, the tangent of the angle of the tangent at the measurement point to the abscissa axis is determined, control commands (electrical signals) are generated for the movement nodes in accordance with the treatment program specified by the doctor and the specified limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction efforts. For this purpose, the control unit is equipped with a measurement and recording of the current time at the moment of force measurement, recording of the nodal points of the curve for automatic change of the distraction rate and rhythm.

[0029] The technical task is to develop a control system for the process of distraction osteosynthesis based on feedback with distraction forces in an automated transosseous compression-distraction apparatus.

[0030] The problem is solved in that the control system of the distraction osteosynthesis process based on feedback with distraction efforts of the transosseous compression-distraction apparatus with automatic movement units contains a processor control unit that sends commands to the movement units in accordance with the treatment program specified by the doctor and records in its memory the course of distraction over time in the form of a distraction force at each movement unit coming from the force sensor of the unit, and reflects the course of distraction in the form of a graph on the display of a personal computer. The control unit is designed with the ability to form a graph of the change in distraction forces over time, determine the tangent of the angle of the tangent of the measurement point at a given time to the abscissa line and, by comparing the angle of inclination with the specified limit values, form control commands to the movement units in accordance with the optimal distraction rate specified by the algorithm.

[0031] In the method of controlling the process of distraction osteosynthesis based on feedback with distraction efforts in an automated transosseous compression-distraction apparatus, during distraction, changes in distraction efforts over time are recorded in the control unit, the tangent of the angle of the tangent at the measurement point to the abscissa axis is determined, control commands (electrical signals) are generated for the movement nodes in accordance with the treatment program specified by the doctor and the specified limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction efforts. For this purpose, the control unit is equipped with a measurement and recording of the current time at the moment of force measurement, recording of the nodal points of the curve for automatic change of the distraction rate and rhythm.

[0032] The process of distraction osteosynthesis is controlled based on feedback from distraction forces in an automated transosseous compression-distraction apparatus.

[0033] The control unit allows independent control and analysis of the elongation process in real time. The control unit analyzes the course of distraction over time and therefore can independently control the elongation mode depending on the data obtained during the measurement process, reflecting the dynamics of changes in distraction forces over time.

[0034] The system and method provide the ability to take into account the level of distraction efforts, their dynamics, and set the optimal distraction rate, using absolute values ​​of distraction efforts in real time to control the lengthening process.

[0035] Dynamic control over the total level of distraction efforts overcome by the external fixation device allows for the regulation of the tempo and rhythm of distraction or compression on each rod individually. This in turn provides the possibility of dosed correction of any deformation simultaneously with the elongation of limb segments. Figure 1

[0036] diagram showing the algorithm for automatic control of limb lengthening with feedback from distraction forces; Figure 2

[0037] diagram showing the dynamics of distraction forces during automatic limb lengthening: I, II and III nodal reference points are indicated; Figure 3

[0038] diagram showing the dynamics of distraction forces during incomplete osteotomy of the tibia (the lower curve reflects the rate of distraction); Figure 4

[0039] diagram showing the rapid drop in distraction forces as the leg lengthens (the lower curve reflects the rate of distraction); Figure 5

[0040] diagram showing the dynamics of distraction forces in patient K. during bilocal femur lengthening: I – proximal subsystem of the Ilizarov apparatus; II – distal subsystem of the Ilizarov apparatus;

[0041] The control system of the distraction osteosynthesis process based on feedback with distraction efforts of the transosseous compression-distraction apparatus with automatic movement units contains a processor control unit that sends commands to the movement units in accordance with the treatment program specified by the doctor and records in its memory the course of distraction over time in the form of a distraction force at each movement unit coming from the force sensor of the unit, and reflects the course of distraction in the form of a graph on the display of a personal computer or smartphone. The control unit is designed with the ability to form a graph of the change in distraction forces over time, determine the tangent of the angle of the tangent of the measurement point at a given time to the abscissa line and, by comparing the angle of inclination with the specified limit values, form control commands (electrical signals) to the movement units in accordance with the optimal distraction rate specified by the algorithm.An algorithm for automatic control of limb lengthening with feedback from distraction forces is shown.

[0042] A method for controlling the process of distraction osteosynthesis based on feedback with distraction forces in an automated transosseous compression-distraction apparatus, in which, during distraction, changes in distraction forces over time are recorded in the control unit, the tangent of the angle of the tangent at the measurement point to the abscissa axis is determined, control commands (electrical signals) are generated for the movement nodes in accordance with the treatment program specified by the doctor and the specified limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction forces. For this purpose, the control unit is equipped with a measurement and recording of the current time at the moment of force measurement, recording of the nodal points of the curve for automatic change of the distraction rate and rhythm.

[0043] Operating procedure, usage.

[0044] Dynamic control over the total level of distraction efforts overcome by the external fixation device allows to regulate the rate and rhythm of distraction or compression on each rod individually. The dynamics of distraction efforts during automatic elongation of the limb is shown: I, II and III nodal reference points are designated.

[0045] This, in turn, provides the possibility of dosed correction of any deformation simultaneously with the lengthening of limb segments.

[0046] The automatic round-the-clock high-fraction mode of limb lengthening is tolerated by patients much easier (painlessly) compared to the generally accepted method of lengthening with the Ilizarov apparatus: there is practically no inflammation of soft tissues in the area of ​​the spokes, no swelling of the limb being lengthened and no sensitivity disorders. All this allows patients to be more active, increase the functional load, which undoubtedly has a positive effect on reparative tissue regeneration.

[0047] X-ray radiological studies have established the advantage in the intensity of bone formation with automatic distraction. Already after two weeks of distraction, the first signs of bone regenerate are detected in the form of a light shadow filling the diastasis between bone fragments, and with further elongation, as a rule, a continuous bone regenerate of uniform density is formed without signs of the so-called "growth zone", which indicates high reparative activity of the bone.

[0048] Continuous monitoring of distraction forces allows us to accurately characterize the process of reparative bone regeneration and prevent possible complications by timely changing the distraction rate. For example, the absence of a complete osteotomy during surgery can be easily detected by a sharp (vertical) increase in forces from the first days of distraction - the tangent of the angle is 2.1 and higher. In this case, after a repeated fracture or osteotomy, the level of forces decreases to zero. The dynamics of distraction forces for incomplete osteotomy of the tibia is shown (the lower curve reflects the distraction rate).

[0049] Timely detection of the decrease in the tangent of the angle to negative values ​​allows for timely diagnosis of the disruption of connections between the tissues being lengthened (disruption of the continuity of the bone regenerate), temporary stopping of the lengthening, and after control radiography, understanding the reasons for what happened and then continuing the distraction in 2–3 days at a slower pace. A rapid drop in distraction forces is shown during lengthening of the tibia (the lower curve reflects the distraction rate).

[0050] Rapid growth of distraction forces at the stage of typical lengthening, when the tangent of the angle of the curve of distraction forces reaches 2.7 and more, indicates the danger of premature consolidation of bone fragments. Something similar was observed during bilocal femur lengthening in patient K. The dynamics of distraction forces in patient K. is shown during bilocal femur lengthening: I - proximal subsystem of the Ilizarov apparatus; II - distal subsystem of the Ilizarov apparatus. Distraction begins 5 days after the operation. For 30 days, distraction forces at both levels are equally uniform with an angle tangent of 0.9, after which a rapid growth of distraction forces is noted in the proximal subsystem of the Ilizarov apparatus - angle tangent of 2.75 (up to 700 N). At the same time, their sharp drop is noted in the distal subsystem - from 480 to 370 N (angle tangent -0.7).

[0051] According to the X-ray examination data, it was established that in the proximal zone there was an elongation of 2.5 cm, in the distal zone – by 5.5 cm. Consolidation of the proximal bone fragments and disruption of the continuity of the distal distraction regenerate were diagnosed. Distraction was stopped and after a closed fracture at the site of bone consolidation, it was continued only in the proximal zone at a rate of 1.5 mm per day with an angle tangent of 0.7. Treatment result: the femur was elongated, as planned, by 10 cm.

[0052] It should be noted that any deviation of the distraction force graph of the Ilizarov apparatus from the typical picture is accompanied by a warning signal on the interface.

[0053] The control unit allows monitoring the process of bone fragments movement along the length, obtaining data on distraction forces on each rod of the external fixation device and the total level of distraction forces of the device over time and the dynamics of forces over the required period of time. Visual observation of the dynamics of forces allows the doctor to justify the necessary changes in the rate and rhythm of distraction. The control unit provides the ability to change the lengthening mode automatically without the doctor's intervention, guided by the limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction forces.

[0054] Feedback with distraction efforts is introduced into the control system of the distraction osteosynthesis process in the automated transosseous compression-distraction apparatus, based on the analysis of force measurement data during a specified real time. In this case, the control program is based on the clinically established dependence of the required distraction rate on individual sections of the typical distraction curve.

[0055] It has been previously proven that the level of distraction efforts, their dynamics, and treatment time are influenced by such factors as the etiology of the disease, the amount of shortening, soft tissue atrophy, muscle strength and range of motion of adjacent joints, and the amount of scar tissue from previous surgeries. The choice of the optimal distraction rate is based on taking into account all the indicators. The uniformity of the dynamics of distraction efforts during limb lengthening has been proven. This confirms the presence of general patterns in the process of distraction osteosynthesis. However, the level of efforts varies significantly, with the highest level differing in congenital limb shortening and in shortening after poliomyelitis. The latter complicates the use of the absolute value of distraction efforts in real time to control the lengthening process. It is more realistic to give a uniform description of the slope of the curve, and the slope angle itself does not characterize the process itself.Here the tangent of the angle tgα between the tangent to the curve and the abscissa axis can be used for the equation of a straight line on the coordinate plane. y=kx+b.

[0056] The number k= tgα is called the angular coefficient of the line. The geometric meaning of the derivative is determined through this angle. The value of the derivative of the function at the desired point is numerically equal to the tangent of the angle of inclination of the tangent to the function at this point.

[0057] What is new is that a method for controlling the process of distraction osteosynthesis has been established based on feedback with distraction efforts in an automated transosseous compression-distraction apparatus, in which, during distraction, changes in distraction efforts over time are recorded in the control unit, the tangent of the angle of the tangent at the measurement point to the abscissa axis is determined, control commands (electrical signals) are generated for the movement nodes in accordance with the treatment program specified by the doctor and the specified limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction efforts. For this purpose, the control unit is equipped with a measurement and recording of the current time at the moment of force measurement, recording of the nodal points of the curve for automatic change of the distraction rate and rhythm.

[0058] The control system for the process of distraction osteosynthesis based on feedback with distraction efforts of a transosseous compression-distraction apparatus with automatic movement units comprises a processor control unit that sends commands to the movement units in accordance with a treatment program specified by a doctor and records in its memory the course of distraction over time in the form of a distraction force at each movement unit coming from a unit force sensor, and reflects the course of distraction in the form of a graph on a smartphone display. The system comprises several automatic racks for extension and retraction in response to one or more electrical signals. A control unit electrically connected to one or more of the plurality of automatic racks, a control unit for sending one or more electrical signals to the plurality of automatic racks. A power source for powering several automatic racks.A computing device that executes control commands.

[0059] The control unit is designed with the ability to generate a graph of the change in distraction forces over time, determine the tangent of the angle of the tangent of the measurement point at a given time to the abscissa line and, by comparing the angle of inclination with the specified limit values, generate control commands (electrical signals) to the movement units in accordance with the optimal distraction rate specified by the algorithm.

[0060] The control system provides for maintaining the growth of distraction forces at a tangent of 0.1-0.6 with a typical dynamic curve at an optimal distraction rate of 1.0 mm / day.

[0061] The control system provides that the growth of distraction forces is maintained at a tangent of 0.7-1.0 with a typical dynamic curve at an optimal distraction rate of 2.0 mm / day.

[0062] The control system provides for maintaining the growth of distraction forces at an angle tangent of 1.0-2.1 with a typical dynamic curve at an optimal distraction rate of 3.0 mm / day.

[0063] The control system provides that when the tangent of the angle is reduced by 0.3, nodal point II is fixed on the dynamic curve of distraction efforts, the distraction rate is reduced to 0.5 mm / day until the beginning of the subsequent growth of distraction efforts, reflected in the growth of the tangent of the angle relative to nodal point II.

[0064] The control system provides that when the tangent of the angle relative to nodal point II decreases to a negative value (-0.5), distraction stops for 3 days and nodal point III is fixed on the dynamic curve of distraction efforts, with subsequent activation of automatic distraction.

[0065] In the method of controlling the process of distraction osteosynthesis based on feedback with distraction efforts in an automated transosseous compression-distraction apparatus, the course of distraction is recorded in the control unit by changes in distraction efforts over time, the tangent of the angle of the tangent at the measurement point to the abscissa axis is determined, control commands (electrical signals) are formed for the movement nodes in accordance with the treatment program specified by the doctor and the specified limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction efforts. For this purpose, the control unit is equipped with measurement and recording of the current time at the moment of force measurement, recording of the nodal points of the curve for automatic change of the distraction rate and rhythm.

[0066] The system and method for controlling the process of distraction osteosynthesis based on feedback with distraction forces are used in an automated transosseous compression-distraction apparatus. The system includes a transosseous automated compression-distraction apparatus containing supports connected to each other by automatic movement units, each of which includes a motor-reducer electrically connected to the controller, and a control unit (base unit).

[0067] Dynamic control over the total level of distraction efforts overcome by the external fixation device allows for the regulation of the tempo and rhythm of distraction or compression on each rod individually. This in turn provides the possibility of dosed correction of any deformation simultaneously with the elongation of limb segments.

[0068] The automatic round-the-clock high-fraction mode of limb lengthening is tolerated by patients much easier (painlessly) compared to the generally accepted method of lengthening with the Ilizarov apparatus: there is practically no inflammation of soft tissues in the area of ​​the spokes, no swelling of the limb being lengthened and no sensitivity disorders. All this allows patients to be more active, increase the functional load, which undoubtedly has a positive effect on reparative tissue regeneration.

[0069] X-ray and radiological studies have established the advantage in the intensity of bone formation with automatic distraction. Already after two weeks of distraction, the first signs of bone regenerate are detected in the form of a light shadow filling the diastasis between bone fragments, and with further elongation, as a rule, a continuous bone regenerate of uniform density is formed without signs of the so-called "growth zone", which indicates high reparative activity of the bone.

[0070] Constant monitoring of distraction efforts allows us to accurately characterize the process of reparative bone regeneration and prevent possible complications by timely changing the distraction rate. For example, the absence of a complete osteotomy during surgery is easily detected by a sharp (vertical) increase in efforts from the first days of distraction - the tangent of the angle is 2.1 and higher. In this case, after a repeated fracture or osteotomy, the level of efforts decreases to zero.

[0071] Timely detection of a decrease in the tangent of the angle to negative values ​​allows for timely diagnosis of a disruption in the connections between the tissues being lengthened (a disruption in the continuity of the bone regenerate), temporary stopping of the lengthening, and after a control radiography, understanding the reasons for what happened and then continuing the distraction after 2–3 days at a slower pace.

[0072] Rapid growth of distraction forces at the stage of typical lengthening, when the tangent of the angle of the curve of distraction forces reaches 2.7 or more, indicates the risk of premature consolidation of bone fragments. Similar was observed during bilocal femur lengthening in patient K.. Distraction began 5 days after surgery. For 30 days, distraction forces at both levels are equally uniform with an angle tangent of 0.9, after which a rapid growth of distraction forces in the proximal subsystem of the Ilizarov apparatus is noted - an angle tangent of 2.75 (up to 700 N). At the same time, a sharp drop is noted in the distal subsystem - from 480 to 370 N (an angle tangent -0.7).

[0073] According to the X-ray examination data, it was established that in the proximal zone there was an elongation of 2.5 cm, in the distal zone – by 5.5 cm. Consolidation of the proximal bone fragments and disruption of the continuity of the distal distraction regenerate were diagnosed. Distraction was stopped and after a closed fracture at the site of bone consolidation, it was continued only in the proximal zone at a rate of 1.5 mm per day with an angle tangent of 0.7. Treatment result: the femur was elongated, as planned, by 10 cm.

[0074] It should be noted that any deviation of the distraction force graph of the Ilizarov apparatus from the typical picture is accompanied by a warning signal on the interface.

[0075] The control unit allows monitoring the process of bone fragments movement along the length, obtaining data on distraction forces on each rod of the external fixation device and the total level of distraction forces of the device over time and the dynamics of forces over the required period of time. Visual observation of the dynamics of forces allows the doctor to justify the necessary changes in the rate and rhythm of distraction. The control unit provides the ability to change the lengthening mode automatically without the doctor's intervention, guided by the limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction forces.

[0076] Feedback with distraction efforts is introduced into the control system of the distraction osteosynthesis process in the automated transosseous compression-distraction apparatus, based on the analysis of force measurement data during a specified real time. In this case, the control program is based on the clinically established dependence of the required distraction rate on individual sections of the typical distraction curve.

[0077] A method for controlling the process of distraction osteosynthesis based on feedback with distraction forces in an automated transosseous compression-distraction apparatus, in which, during distraction, changes in distraction forces over time are recorded in the control unit, the tangent of the angle of the tangent at the measurement point to the abscissa axis is determined, control commands (electrical signals) are generated for the movement nodes in accordance with the treatment program specified by the doctor and the specified limit values ​​of the tangent of the angle relative to the nodal points of the curve of the total distraction forces. For this purpose, the control unit is equipped with a measurement and recording of the current time at the moment of force measurement, recording of the nodal points of the curve for automatic change of the distraction rate and rhythm.

[0078] The production of the system and implementation of the method is possible using known transosseous automated distraction devices [2]. Patent literature

[0079] patent US20220354539A1.

[0080] patent RU 2763644 Non-patent literature

[0081] Blynsky Fedor Yuryevich, Sul'din Maksim Petrovich Control system of distraction efforts in the process of automated limb lengthening / Vectors of well-being: economy and society. 2013. No. 3 (9).l

Claims

A control system for the process of distraction osteosynthesis, based on feedback from the distraction forces of a transosseous compression-distraction apparatus with automatic movement units, containing a processor control unit that sends commands to the movement units in accordance with a specified treatment program and records in memory the course of distraction over time in the form of a distraction force at each movement unit, coming from a force sensor of the movement unit, and reflecting the course of distraction in the form of a graph on the display of a personal computer, wherein the control unit is designed with the ability to generate a graph of the change in distraction forces over time, determine the tangent of the angle of the tangent of the measurement point at a given time to the abscissa line and, by comparing the angle of inclination with the specified limit values, generate control commands to the movement units in accordance with a specified distraction rate algorithm. The control system according to item 1, characterized in that the growth of distraction forces is maintained at an angle tangent from 0.1 to 0.6 on the dynamic curve at a distraction rate of 1.0 mm / day. The control system according to item 1, characterized in that the growth of distraction forces is maintained at an angle tangent from 0.7 to 1.0 on the dynamic curve at a distraction rate of 2.0 mm / day. The control system according to item 1, characterized in that the growth of distraction forces is maintained at an angle tangent from 1.0 to 2.1 on the dynamic curve at a distraction rate of 3.0 mm / day. The control system according to paragraphs 2-4, characterized in that when the tangent of the angle decreases by 0.3, the nodal point II on the dynamic curve of distraction forces is fixed, the distraction rate decreases to 0.5 mm / day until the beginning of the subsequent growth of distraction forces, reflected in the growth of the tangent of the angle relative to the nodal point II. The control system according to item 5, characterized in that when the tangent of the angle relative to the nodal point II decreases to the value of “-0.5”, the distraction is stopped for 3 days and the nodal point III is fixed on the dynamic curve of distraction forces, with subsequent activation of automatic distraction. A method for controlling the process of distraction osteosynthesis based on feedback with distraction forces in an automated transosseous compression-distraction apparatus, in which, during distraction, changes in distraction forces over time are recorded in the control unit, the tangent of the angle of the tangent at the measurement point to the abscissa axis is determined, control commands are generated for the movement nodes in accordance with a specified treatment program and specified limit values of the tangent of the angle relative to the nodal points of the curve of the total distraction forces, while the time is measured and recorded at the moment of force measurement, and the nodal points of the curve are also recorded for automatic change of the tempo and rhythm of distraction.

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