Patent ID: 12201305

DETAILED DESCRIPTION

With reference to those figures, and in particular to the example ofFIG.1, a driving system for an ultrasonic device according to the present disclosure is globally and schematically indicated with the reference number1.

It is worth noting that the figures represent schematic views and are not drawn to scale, but instead they are drawn so as to emphasize the important features of the disclosure. Moreover, in the figures, the different elements are depicted in a schematic manner, their shape varying depending on the application desired. It is also noted that in the figures the same reference numbers refer to elements that are identical in shape or function. Finally, particular features described in relation to an embodiment illustrated in a figure are also applicable to the other embodiments illustrated in the other figures.

The system1according to the present disclosure allows to drive, by implementing a given method, a handset which is able to generate ultrasounds for medical use. In particular, the system1is used for bone cement removal or also for osteotomy operations. It is also pointed out that, in the context of the present disclosure, the driving system1will also be indicated using the term “generator”, as known in the art.

As shown schematically inFIG.1, the system1comprises a housing2which encloses all its main components.

In particular, the system1comprises first of all a power supply unit3(indicated also as PSU) for converting the input voltage into a DC voltage to be supplied to the system components. The PSU3is therefore connected to the power supply input of the components of the system1to be powered, such as a control unit, a pair of power boards, etc. In order to reduce the electromagnetic interferences, an EMI filter4is arranged at the input of the PSU3, as known in the art.

In an embodiment, the PSU3provides a DC voltage of 24 V, as well as a second DC voltage of 48 V which is used in particular for the generation of ultrasounds.

The driving system1according to the present disclosure is in fact intended to control the operation of a handset5used for the removal of bone cement during prosthesis revision procedures, as well as for cutting bone portions during osteotomy operations, by using ultrasounds. Conveniently, as it will be described in detail below, the system1allows only one type of handset5to be used for both the bone cement removal and osteotomy operations.

More specifically, the handset5comprises a main body which encloses and acts as a protective element for ultrasound generating means, which include a piezoelectric transducer and a horn, as known in the art. The handset5is connected to the driving system1by means of an electric cable, said electric cable being associated with the handset5by means of a suitable socket formed preferably at the distal end of the body of the handset5. The piezoelectric transducer is designed to transform the electric energy supplied by the generator into mechanical vibrations, having a frequency of about 28.350 kHz. However, the system1according to the present disclosure is able to control the generation of ultrasounds within a wide range of frequencies, i.e. from 20 kHz to 100 kHz, with power levels ranging from 0 to 350 W, this system being particularly versatile and able to be used in various applications.

The horn of the handset5is apt to amplify and transfer the vibrations generated by the piezoelectric transducer to a tool T (also called “probe”) connected to it.

The handset5therefore comprises connection means for connecting it to the tool T to which the generated ultrasounds are transmitted. Preferably, the connection means are in the form of a threaded connection at the proximal end of the horn.

The tools T associated with the handset5may have different forms and functions and will not be described in the present detailed description, the form and functions of these tools (as well as the internal structure of the handset5) not forming part of the present disclosure. What is of importance for the purposes of the present description is that specific tools T are intended for specific operations, their form and size varying depending on the operations carried out and that, conveniently, the system1according to the present disclosure is able to drive a single handset5to be used in each operation and to identify the tool T associated with this handset, as will be described further below.

The system1according to the present disclosure comprises a central control unit6intended to control and manage its main functions, such as the generation of the ultrasounds, the communication between the various components of the system1, the communication with the handset5and the control thereof.

In particular, the control unit6comprises a control board6′ which receives at its input 24 volts from the PSU3and is provided with its own integrated CPU which carries out specific instructions for controlling the ultrasounds.

For example, the CPU is configured to receive data from an analog-digital converter integrated in the control board6′ and connected to it, in particular in order to evaluate the actual frequency deviation of the generated ultrasounds from the nominal frequency, the amplitude of the output current and the output voltage and their temporal relationship. More particularly, the data input to the analog-digital converter is for example feedback data from the handset5or other components of the system. The CPU is therefore able to receive voltage and current data from the handset5in order to track the operating frequency thereof and therefore check the correct generation of the ultrasounds. In accordance with a method described further below, this CPU is structured and configured to check also the state of the piezoelectric transducer and the tools T associated with the handset5. By way of a non-limiting example, the CPU of the control board6′ may be an ARM Cortex processor.

Furthermore the CPU of the control board6′ is operationally connected to a PWM controller (not shown in the figures), which is also integrated in the control board6′ and is adapted to manage phase-shifted PWM signals from which activation signals are generated, these activation signals being then used by a power board for the generation of ultrasounds, as will be described further below.

In an embodiment, the analog-digital converter and the PWM controller are integrated in the ARM Cortex processor and form part of the same control loop for management of the ultrasounds, said control loop being managed by the CPU as indicated above.

The control board6′ also comprises a power supply input apt to receive from the PSU3the DC voltage, in particular a 24 volt DC voltage. This power supply input is provided with mechanical elements which ensure protection against potential vibration of the control board6′. Furthermore, the power supply input of the control board6′ also provides filtering of the high-frequency disturbance components so as to increase the performance of the system.

The control board6′ also comprises a portion for data communication with the handset5which allows the latter to be interfaced with the system1. In particular, the control board6′ comprises a series of I/O ports for the communication with the handset5. The communication with the handset5is managed by a communication buffer using the RS485 standard and, according to a preferred embodiment, it is performed by means of a communication circuit, as will be described below.

The system1according to the present disclosure also comprises means which produce as an output a high-voltage signal for the generation of the ultrasounds. In particular, the system1comprises at least one power board7connected to the control unit6and adapted to receive from it a series of signals (for example four PWM signals) and to generate, based on these signals, a signal with a power suitable for being sent to the handset5for generation of the ultrasounds.

The power board7receives the 24 volt and 48 volt power supplies from the PSU3and communicates with the control unit6, as indicated above.

The power board7therefore comprises means able to generate and send to the piezoelectric transducer of the handset5a signal suitable for the generation of the ultrasounds.

Furthermore, the power board7is provided with its own CPU able to manage its operation independently and control the generation of the ultrasounds. For example, this CPU is adapted to generate a logic signal for driving those components of the power board7especially designed for the generation of the ultrasounds.

The CPU integrated in the power board7also receives data from the handset5for identification thereof and is able to manage a system for controlling the temperature of the power board7on the basis of data from a temperature sensor integrated therein.

Preferably, the system1comprises a pair of power boards7which are connected to two corresponding output channels, wherein during operation of the system1only one of these output channels is activated by the control unit6. It is also pointed out that, although the system according to the present disclosure preferably has two power boards7, any number of power boards may be provided depending on the requirements and/or the circumstances. The presence of a second additional power board7ensures a greater safety and efficiency of the system, since it provides a second output available during the operations.

Furthermore, the system1according to the present disclosure comprises connection means13which allow it to be connected to the handset5, in particular allow connection between the handset5and the control unit6, as well as the connection between the handset5and the power board7. Each power board7is therefore preferably arranged between the control unit6and the connection means13.

The connection means13are adapted to transmit to the handset5both data and the power supply necessary for the operation thereof and comprise a socket that allows physical interfacing of this handset5with the system1.

The handset5is connected to the connection means13of the system1by means of a cable (not shown in the figures), which allows the transfer of both data and power supplies. This cable comprises a connector with four poles, two of which are used for the transmission of the signal for generating the ultrasounds (in particular two high-voltage signals, for example of 600 V), one of which is used for powering the handset and one for data transfer, this cable comprising an outer silicone sheath. Two screening braids are also provided for transfer of the reference potential, both of the earth protection and the communication bus.

The connection means13comprise a communication circuit (or communication interface) connected to the socket for connection to the handset5. The communication circuit of the connection means13receives from the power board7the high-power signal for generating the ultrasounds and transmits it to the handset5, and it is also connected to the control unit6, in particular to the control board6′, in order to send/receive data and receive a 24 V power supply. The communication circuit is also provided with its own CPU which manages the data communication with the handset5, said communication being performed using the RS485 standard.

In other words, the control unit6is able to communicate with the handset5, for example in order to identify the handset itself, receive its activation signal or check the frequency of the ultrasounds, by means of the communication circuit of the connection means13, which is provided with its own RS485 transceiver for continuous communication with said handset5.

Similarly, the power board7sends to the handset5the high-voltage signal for generation of the ultrasounds by means of a special circuit of the communication means13, said circuit being for example arranged alongside the communication circuit and being provided with means for isolation against nominal voltages of up to 600 V, so as not to interfere with the communication bus of the communication circuit, said screening being separate from the communication circuit of the handset.

The communication bus is instead used only for data communication, preferably by means of the RS485 transceiver, as indicated above.

The handset5has an architecture comprising a circuit similar to the communication circuit of the connection means13and in communication therewith. In particular, the handset5also is provided with a communication circuit (comprising for example a microprocessor) which in turn comprises a memory unit (for example an EEPROM memory) containing all the information useful for the identification thereof. For example, the memory unit of the handset5may comprise its serial number, which is communicated to the control unit6of the system1as soon as this handset5is connected, thus allowing immediate identification of the handset. The circuit also comprises a temperature sensor, means for driving an LED indicating the status of the system and, in a preferred embodiment, a Hall-effect sensor for activation thereof, the control unit6being configured to receive the data from these sensors.

The control unit6is therefore configured to communicate and receive data from this communication circuit integrated in the handset5, said communication occurring via the communication circuit of the connection means13, as indicated above. Essentially, the driving system1provides for the powering of the handset5(via the circuit of the connection means13) and is characterized by a two-way (bidirectional) data exchange with said handset.

Furthermore, the control board6′ is operationally coupled to a memory unit MEM adapted to store data of the system1. In particular, the memory unit MEM is included in the control unit6and is connected to control board6′ so as to keep stored all the operating parameters for the different types of operation, such as the operating parameters for the bone cement removal operations or the operating parameters for the osteotomy operations.

Even more particularly, the memory unit MEM is included in a computerized unit8of the control unit6, this computerized unit8being in data and power communication with the control board6′ and supporting the software which manages all the functions and the logic of the system1. The control board6′ is responsible for the management of the communication between the computerized unit8and the power board7. In accordance with the architecture described above, the computerized unit8includes the system software, while the control board6′ includes the firmware. The control board6′ and the computerized unit8communicate with each other via the RS485 standard. Obviously, as illustrated above, the architecture described does not limit the scope of the present disclosure and other types of architecture may be used depending on the particular requirements and/or circumstances.

The memory unit MEM contains data matrices comprising all the information relating to the handset and the tools which can be associated with it, wherein all the operating parameters and the expected operating conditions are associated with each operation mode which can be selected. As will be described in detail below, the system1according to the present disclosure allows the operator to select the desired operation mode and automatically sets the parameters stored for that mode, whereby a given tool to be connected to the handset corresponds to said mode.

Advantageously according to the present disclosure, the control unit6is configured to send a signal Sg1to the handset5and to receive from it a response Sg2to said signal Sg1which has been sent.

In particular, when executing the instructions of the software contained in the memory unit MEM, the control board6′ sends to the piezoelectric transducer of the handset5the signal Sg1, which may be defined as being a low-power stimulus signal, and measures the response Sg2with the aim of checking an operating condition (or operating state) of the ultrasonic device based on said response Sg2received from the handset5.

The signal Sg1which is sent to the handset5is in particular a signal with a frequency variable within a given frequency range, from a minimum frequency fmin to a maximum frequency fmax, as indicated inFIG.2. Clearly the selected frequency range may vary depending on the application.

Even more particularly, the frequency range [fmin, fmax], which represents therefore the scanning range of the handset5and of any tool5associated with it, is chosen so that the expected resonance and anti-resonance frequencies of the tool T fall within this scanning range (which may be for example between 25 and 35 kHz). The resonance and anti-resonance frequencies are determined beforehand by means of numerical simulations of the response of the tool T to the variable-frequency signal Sgt. The signal Sg1is therefore a wide-band and low-power stimulation signal (with frequency variable within the spectrum concerned), and therefore is not destructive even in the case of a fault of the handset or the cable. Moreover, the signal Sg1is preferably a sinusoidal voltage signal, the amplitude of which is confined within a range defined between a minimum amplitude Vmin and a maximum amplitude Vmax, as shown inFIG.2. It is also pointed out that, although the handset/tool system has a multitude of resonance frequencies, the scanning range is such that only one longitudinal resonance (and anti-resonance) frequency is identified.

Even more particularly, the system1of the present disclosure is such that, by means of the control unit6and the aforementioned signal Sg1, it is able to check a plurality of operating conditions of the ultrasonic system, including at least one of the following: the state of the piezoelectric transducer of the handset5, the type of tool T associated with the handset5, and/or the state of said tool T. In the context of the present disclosure, the particular operation mode is for the example the type of operation to be performed, while “operating condition” is understood as meaning for example the state of the handset or the type of tool associated with it, said operating condition being checked by means of the signal Sg1and the response Sg2and compared with the expected values for the particular operation mode selected. This is particularly interesting since, in accordance with the present disclosure, a single handset5is used for all the types of operations and therefore an optimum feedback is obtained for the operator.

The signal Sg1sent to the handset5is the same both for evaluating the state of the piezoelectric transducer (namely for evaluating the response of the handset5without the tool T connected) and for evaluating the handset5with the tool T connected thereto, also checking the quality of the connection.

During the frequency scanning, the driving system1is configured to measure continuously the electric current absorbed and the electric potential based on the response Sg2. In an embodiment, knowing the temporal variations of the voltage V and the current I, V(t) and I(t), respectively, the driving system1is configured to calculate, by means of the central unit6, the impedance (in a manner known in the art) as a function of the time of the system, Z(t). In this way, knowing the frequency variation of the signal as a function of the time, f(t), it is possible to create a graph [f(t), Z(t)] which represents the so-called impedance curve of the system. In other words, by means of the response signal Sg2, it is possible to calculate the impedance curve of the system, namely the impedance as a function of the scanning frequency, as shown inFIG.2, thus providing the frequency response of the system.

For example, when a system comprising the handset5and tool T is scanned, as shown inFIG.2, owing to the longitudinal resonances and anti-resonances (namely the longitudinal deformations which propagate in the mechanical system), the impedance curve shows two characteristic peaks: the first peak identifies the resonance frequency fr (minimum value thereof) while the second peak identifies the anti-resonance frequency fAR (maximum value thereof). In addition to the aforementioned values, it is possible to obtain characterizing information also from the specific behaviour of the first and second derivatives Z′(f) and Z″(f). Each handset-tool system has its own characteristic impedance curve, such that different tools, owing to their form factor (generally they are narrow and elongated), modify substantially the impedance curve and therefore are characterized by their own specific curve, such that the type or category of tools connected to the handset5may be identified automatically by means of an analysis of the said impedance curve, as will be illustrated below.

The analysis of the impedance curve also allows the state of the piezoelectric system to be determined and in particular any breakages in the mechanical components of the handset-tool system to be detected.

The handset5alone, instead, does not have such a characteristic impedance curve.

In the case where the operating condition checked by the control unit6is the state of the piezoelectric transducer of the handset5(and therefore when the tool T is not associated with the handset), the signal Sg1is defined as above and the response Sg2of the handset5to this signal Sg1which is sent corresponds to the frequency response curve of the piezoelectric transducer, namely corresponds to the characteristic response (again in the form of an impedance curve) of the handset alone assessed without the tool T, providing an indication of the state of this transducer. The frequency response curve of the piezoelectric transducer, measured when no tools T are associated with the handset5, therefore represents the basic model of the ultrasound generating system which comprises the piezoelectric transducer and the whole mechanical amplification and transmission system. It has its peak at the emission frequency of a piezoelectric transducer which is functioning correctly (e.g. about 28.350 kHz).

In the context of the present disclosure, the term “frequency response” therefore always indicates the variation in impedance of the system which is stressed by a variable-frequency voltage. Obviously, other physical parameters equivalent to the impedance may be calculated following the stimulus, if required by the circumstances.

The memory unit MEM comprises data relating to the optimum frequency response curve of the piezoelectric transducer, so that it is possible to check the state of this transducer by carrying out a comparison between the measured real curve and the stored expected curve, as will be described further below in greater detail.

As illustrated above, in the case where a tool T is associated with the handset5(and therefore in the case where the control unit6checks the type of tool T associated with the handset5or the state of this tool), the response of the handset5to the sent signal Sg1varies depending on the type of tool T connected, since the different form of the tools leads to different responses, in particular different resonances.

In particular, the control unit6, in response to the sending of the check signal Sg1(which is the same as that for the handset5alone), is configured to measure the characteristic impedance curve of the tool T upon variation of the frequency within the frequency range as previously defined, said impedance curve being unique for each tool T or in general for each category of tools T.

The driving system1is therefore configured to recognize the tool T by performing a comparison with the stored data, comparing in particular the resonance frequencies.

In this case, the memory unit MEM comprises data relating to the impedance curve as a function of the frequency for all the tools T which may be associated with the handset5, and the control unit6is configured to compare the measured response curve with the stored expected response curve for a given tool associated with the operation mode selected by the operator.

In general, the comparison carried out by the control unit6allows the settings of the ultrasonic system to be checked for their correctness, and an error signal is generated in the case the values measured do not tally with the expected values, thereby increasing the efficiency, the reliability and the safety of the system.

Even more particularly, the evaluation of the response signal Sg2of the system is carried out over the whole scanning range, defining a data vector (and therefore a multi-dimensional vector having modulus and phase for each frequency of the band) having a frequency step variable between 0.1 Hz and 20 Hz. The aforementioned evaluation is based on the calculation of the distances between the expected vector and the vector defined according to the response Sg2(and therefore not only on the mono-dimensional values of the resonance frequencies).

In other words, preferably, the checking of the tool associated with the handset is performed not only by comparing the resonance frequency value with an expected value for that tool, but also by comparing (by means of classification and clustering) the whole impedance curve of the tool T with a set (or “cluster”) of stored reference curves of similar tools. The control unit6is therefore configured to implement a multi-dimensional comparison which takes into account different mathematical characteristics of the impedance curves (form, maximum values, minimum values, first derivative, second derivative, etc.). Clearly, the aforementioned comparison also involves, at least indirectly, a comparison between the resonance and anti-resonance frequencies. Consequently, the algorithms implemented by the control unit allow to compare the entire impedance curve in its mathematical characterization (values of the resonance and anti-resonance frequencies, first, second and third derivatives, etc.), in particular by means of machine learning or artificial intelligence techniques, with reference models (sets of previously classified impedance curves) which characterize the expected behaviour that is specific for each handset-tool combination.

An error is generated by the control unit6if the measured values do not match with the expected values which have been stored.

The driving system1is configured to provide the response signal Sg2by means of the feedback from the voltage and current vectors which power the handset5, suitably conditioned and galvanically isolated from the output of the driving system1, which by means of two galvanic barriers, both for the voltage feedback and for the current feedback, electrically separate the signals sent to the analog-digital converter from the signals sent to the piezoelectric transducer. The isolation barrier uses the transmission of the magnetic field to separate the high-voltage primary circuits from the secondary measurement circuits and is such that it does not alter the phase relationship between the respective voltage and current vectors generated. The voltage and current feedback of the secondary circuits of the barrier is conditioned by wide-band, linear, differential amplifiers before being applied to the analog circuits for extraction of the effective value and the power factor of the original parameters and then applied to the analog sampling circuits of the analog-digital converter.

As mentioned above, according to the present disclosure, the system1allows the operator to select the desired operation mode from a plurality of operation modes stored in the memory unit MEM, each operation mode corresponding to a specific tool T to be associated with the handset5.

In this connection, the system1according to the present disclosure comprises a user interface9configured to allow the entry and display of operating parameters or the selection of the desired operation mode from among a plurality of operation modes whose operating parameters have been stored beforehand in the memory unit MEM, said user interface9thus allowing direct interaction with the system. Based on the settings entered by the operator via the user interface9, the control unit6sets the most appropriate inputs/outputs for the power board7.

Preferably, the user interface9is a touch screen interface, even though other solutions obviously fall within the scope of the present disclosure.

The operation of the user interface9is controlled by the computerized unit8andFIG.3shows an example of such an interface in accordance with an embodiment of the present disclosure.

In particular, the user interface9is such as to display to the operator initially a plurality of operation modes to be selected and, once the desired mode has been selected, the corresponding operating parameters are automatically set. At this point, the operator has the option of activating (for example by pressing a given pushbutton) the function for checking the state of the handset5and/or the tool T associated with it (namely the operating condition check), wherein the control unit6is configured to generate the control signal Sg1and compare the response Sg2received with information stored in the memory unit MEM, as indicated above. In accordance with an embodiment of the present disclosure, the checking of the state of the system may also be performed automatically each time the system is activated. In this way, the check may be performed either manually or automatically or following a confirmation request of the user interface9, for example after a tool T has been associated with the handset5.

As shown inFIG.3, in the case where the measured response differs from the expected response, an error signal is generated by the central unit6and is converted into an error message which is displayed by means of the user interface9.

With reference again toFIG.1, acoustic signalling means12(such as a loudspeaker) are also provided, said means12being able to signal to the operator any error or danger situations.

Furthermore, it is pointed out that, when a tool T is associated with the handset5, the response Sg2of the handset5to the input signal Sg1is determined by the combination of the effect due to the piezoelectric transducer and the effect due to the presence of the tool T, and consequently any deterioration of the piezoelectric transducer causes a deviation of the characteristic response of the tools from that which is expected.

Advantageously, the control unit6is also configured to discriminate between the response due to the piezoelectric transducer and the response due to the type of tool T used.

The control unit6is in fact able to implement an automatic learning procedure which makes use of machine learning and/or artificial intelligence techniques. In particular, the learning procedure is based on classification and clustering. In this way, by means of the machine learning procedure, the control unit6is able to process the response Sg2from the handset5so as to determine the extent to which the response is due to the deterioration of the piezoelectric transducer. This is particularly advantageous since a variation of the response of the piezoelectric transducer (for example due to ageing) could result in incorrect identification of the tool T associated with the handset5.

In this way, conveniently, it is possible to establish in an efficient and reliable manner whether the tools T mounted on the handset5effectively correspond to the operation mode selected.

The control unit6is also able to check, by means of an analysis of the frequency response of the handset5, the state of the tools T, for example the presence of any fissures which cause a variation in the response.

Furthermore, it is known that, during operation of the ultrasonic system, the temperature of the tool T associated with the handset5, as well as the temperature of the treated area, may reach high levels which are potentially dangerous for the instrument and the patient. For this reason, the handset5comprises a duct for circulation of a cooling medium which is supplied at the tool and therefore at the treated zone of the patient.

The flow of the cooling medium (which normally consists of a physiological solution) is ensured by means of a peristaltic volumetric pump10which is incorporated in the housing2of the driving system1and is able to control and meter the flowrate of the cooling medium.

The pump10is operated by an actuator11, such as a footswitch, this actuator11being connected to the central unit6, in particular to the control board6′ and sending an activation signal to said control board6′. The control board6′, in response to the activation signal received from the actuator11, sends in turn an activation signal to the pump10which is thus able to convey the cooling fluid to the handset5via a duct14connected to the duct of the handset5. The operation of the pump10is therefore controlled by the control board6′, with which it is able to communicate.

By means of a series of pipes passing through the pump10, it is possible to connect a cooling medium container (which may be situated outside the housing2of the system1) to the duct14of the system1and the handset5, the latter being able to convey the correct amount of cooling medium into the treatment zone.

Again with the aim of reducing the problems associated with the increase in temperature of the treated area, the control unit6is configured to time the operation of the handset5. More specifically, at predefined intervals (for example every 30 seconds) the activation of the piezoelectric transducer is interrupted for a given time period (generally a few seconds), with the interruption of the power supply towards the ultrasound system. This mode of operation ensures indirect control of the temperature and also gives the operator time to clean and check the working area. Furthermore, such a functional feature is able to overcome the problems associated with drilling of the cortical bone.

In any case, as illustrated above, the handset5is provided internally with a temperature sensor and the control unit6is able to receive data relating to the temperature reached inside the handset5. In the case of risk of damage to the device, the control unit6is able to interrupt for a given period of time (for example a few seconds) the power supply and therefore the generation of the high-power signal emitted by the power board7.

Furthermore, the control unit6, which is in communication with the handset5, is able to signal any excessive pressure and/or flexing of the tool exerted by the surgeon during the operations. This feedback ensures optimum use of the instrument, at the same time safeguarding the piezoelectric transducer and the tools T, thus increasing the safety for the operator and the patient.

Furthermore, the system1according to the present disclosure is able to alert the operator (for example by means of a message displayed on the user interface9or an acoustic signal emitted by the acoustic signalling means12) when the tool T comes into contact with materials having different density, such as steel, titanium, etc. For this purpose, the control unit6is configured to implement feedback control, for example based on the measurement of the frequency of the ultrasonic resonances, which may vary depending on the material with which the tool T makes contact.

As mentioned above, conveniently according to the present disclosure, the driving system1is such that a same handset5may be used both for bone cement removal and for osteotomy operations; in this case it is only required to select and associate with the handset5the tool T suitable for the operation to be performed. The system1according to the present disclosure is therefore able to drive a same piezoelectric transducer for different types of operation, providing different powers and managing different frequencies so as to be compatible with both applications. The adjustment of the power of the piezoelectric transducer is managed by the control unit6, ensuring extreme flexibility of the system.

The possibility of checking the correctness of the tool T associated with the handset5by means of frequency scanning, as described above, is thus particularly advantageous, since both tools for bone cement removal and tools for performing osteotomy operations may be associated with a same handset.

With reference now toFIG.4, the present disclosure also refers to a method for driving an ultrasonic device for bone cement removal and/or osteotomy operations, said method comprising the preliminary step of establishing a connection between a control unit6and a handset5of the ultrasonic device by means of specially designed connection means13.

The method then comprises a step of sending a signal Sg1to the handset5and a subsequent step of receiving from the handset5a response Sg2to said sent signal Sg1.

Finally, advantageously, based on the response received from the handset5, a step of checking an operating condition of the ultrasonic device is performed.

In particular, in accordance with the method according to the present disclosure, the checking step comprises a step of sending to the handset5a variable-frequency test signal as defined above, said step being followed by a step of comparing the frequency response curve of the piezoelectric transducer with previously stored information. In this way, when no tools are associated with the handset5, it is possible to check the state of the piezoelectric transducer and therefore the condition of said handset5.

Conveniently, the method also comprises a step of selecting, via a suitable user interface9, an operation mode from among a plurality of stored operation modes. For example, it is possible to choose between a bone cement removal mode and an osteotomy operation mode. Once the desired mode has been selected, all the operating parameters are automatically set, and the operator is able to carry out the operation. Clearly, it will be necessary to associate with the handset5the appropriate tool T for the mode selected, said handset5comprising a single threaded connection for each type of tool and therefore being able to be used both for cement removal operations and for osteotomy operations.

Even more conveniently, the method comprises a step for checking that a tool T, or a category of tools, associated with the handset5corresponds to the operation mode selected.

More specifically, the check comprises firstly a step of sending to the handset5the signal Sg1defined above and then measuring the characteristic impedance curve of the tool T upon variation of the frequency in response to the signal sent.

Furthermore, the method comprises a step of generating and displaying an error signal if the response from the handset5differs from the expected response.

In particular, a step of generating and displaying an error signal is envisaged if the responses measured are different from the previously stored expected responses. In particular a comparison at least of the measured resonance frequencies and the expected frequencies is carried out (generally a comparison of data vectors is carried out, as described above) and the error signal is generated if the frequencies measured are outside a predefined range around the expected frequencies.

Furthermore, the aforementioned step of displaying the error signal also comprises the indication of a solution to said error, so as to assist the operator in the most efficient manner possible. Help messages for the operator are in fact provided both during set-up and during error resolution, significantly improving the interaction between system and operator.

If instead no errors are generated, the operation of the handset5is enabled, said handset5being therefore ready to generate the ultrasounds for example following the pressing of a given control button by the operator.

A temperature control step is also provided: in particular it is possible to check whether the temperature inside the handset5is above a given threshold value.

Furthermore, a step of checking whether a tool T associated with the handset5comes into contact with various materials is also provided, this being based in particular on the measurement of the variation in the ultrasonic resonance frequencies.

In conclusion, the present disclosure provides to equip an ultrasonic device with a driving/control system configured to send to a handset of the device an input signal and to measure the characteristic response of the handset and/or the tool associated with the handset to this input signal, this response being compared with expected responses previously stored in the memory of the driving system. In this way, the present disclosure allows data exchange between the handset and the driving system, providing the operator with useful information such as feedback about the state of the handset and the type of tools associated with it and/or their state.

Advantageously according to the present disclosure, the proposed system is configured to exchange data bidirectionally with the handset and, following suitable checks, provides the operator with a plurality of feedbacks, increasing the efficiency and at the same time the safety of the ultrasonic device.

In fact, once the operation to be performed has been selected, the operator is firstly guided when choosing the tool suitable for the operation selected, and the system, by executing the instructions of a suitable computer program, allows to evaluate whether the chosen tool corresponds to the selected mode, and at the same time evaluate the state of the piezoelectric transducer, thus carrying out a full diagnosis of the ultrasonic system. This diagnosis is carried out in real time and very rapidly, by executing a frequency scan of the handset by means of the control unit of the system according to the present disclosure.

The proposed system therefore effectively solves the technical problem of the present disclosure, improving significantly the interaction between ultrasonic system and operator, providing immediate feedback about the operating conditions of said ultrasonic system.

There is also the possibility of using a single handset for each type of operation, the system according to the present disclosure allowing a feedback relating to the type of tool used, and therefore being able to indicate whether the tool associated with the handset is the right one.

Finally, it is also envisaged the possibility of measuring the state of the tools, again with the aim of improving the performance and the safety of the ultrasonic device.

From the foregoing it will be appreciated that, although specific embodiments of the disclosure have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the disclosure, all included in the protection scope as defined by the appended claims.

The various embodiments described above can be combined to provide further embodiments. These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.