The present invention relates to medical surgical devices suitable for aiding doctors during surgery.

More in particular, the device comprises the kit of necessary tools to allow a surgeon to repair bone fractures, with an acceptable level of compression in the peri-implant vascular bed. As is known, in orthopedic and other kinds of surgery one of the techniques employed to repair bone fractures is to provide for the insertion of stabilization screws, which are potentially associated with a stabilization plate. For this purpose, the surgeon utilizes a drilling tool that drills and threads the implant sites for the screws.

The correct insertion of the screws entirely depends on the surgeon's medical judgment and professional experience and on his evaluation of the bone quality, which, as is known, may radically vary from one implant site to the next even in the same bone.

The surgeon must therefore adjust the implant to the type of bone he believes to have identified so as to achieve a physiological balance between the primary stability of the implanted screws and compression of the vascular bed at the peri-implant site.

In order to carry out a stable and secure implant for the patient, the surgeon must therefore correctly evaluate the density of the bone tissue being operated on.

It follows that the speed and rotation torque of the drill (from which power can be obtained), as well as the diameter of the milling and/or tapping drill bit must be matched to the density of the bone, as subjectively evaluated by the surgeon from time to time.

An objective of the present invention is therefore to provide a kit for orthopedic and other kinds of surgery, which exploiting "power" and "electricity" and the analysis of "sound waves" during the work, becomes particularly advantageous in the repair of bone fractures, allowing to overcome the technical limitations encountered in the prior art.

Within this scope, a further objective of the present invention is to provide a kit for orthopedic and other kinds of surgery used in the repair of bone and other types of fracture, which may aid the surgeon in the successful outcome of the surgery.

A further objective of the present invention is to provide a kit for orthopedic and other kinds of surgery, in particular used in the repair of bone and other types of fracture, well suited for achieving the desired primary stability of the implant and with acceptable compression of the peri-implant vascular bed.

Another objective of the present invention is to provide a kit for orthopedic and other kinds of surgery, in particular for the repair of bone and other types of fracture, aiding in speeding up the regeneration process thus limiting the potential for infections caused by the implanted devices and tools.

Further characteristics and advantages of the present invention will become more apparent hereinafter from the following description of a preferred, though not exclusive, embodiment of the kit for the repair of bone and other types of fracture, which is illustrated, by way of an indicative, but not limitative, example in the accompanying drawings, where:

Figure 1 is a schematic view of the kit for orthopedic and other kinds of surgery, according to the present invention, when employed during an orthopedic surgery to repair a bone fracture;

Figure 2, is an enlarged view of the work area of the surgical instrument;

Figure 3, is a reproduction of the surgical instrument;

Figure 4, is a block diagram of the orthopedic surgery kit with all its components;

Figure 5, shows a Fast Fourier Transform (FFT) analysis of the spectrum of background noise sample records, in a three-dimensional graph;

Figure 6, shows a FFT analysis of the spectrum of background noise sample records, in a two-dimensional graph;

Figure 7, shows a FFT analysis of the spectrum of background noise sample records , while the motor is turned on, in a three-dimensional graph; said figure depicts the same features as in figures 5 and 6, with the addition of a feature slightly below 40 kHz, which represents the noise of the motor;

Figure 8, shows a FFT analysis of the spectrum of background noise sample records , while the motor is turned on, in a two-dimensional graph; said figure depicts the same features as in figures 5 and 6, with the addition of a feature slightly below 40 kHz, which represents the noise of the motor;

Figure 9, shows a FFT analysis of the spectrum of sample records, during work with a dedicated endodontic motor, with a programmed number of rpm (Revolutions per Minute) and torque for rotating or reciprocating nickel-titanium (NiTi) instruments and the failure of an endodontic instrument utilized in the root canal of a suitably prepared freshly extracted human tooth, in a three-dimensional graph. Note the vertical feature at 13.45 seconds, corresponding to the moment of failure; some peaks are present at the instant of failure at particular frequencies. Furthermore, similar features are present at other times, preceding the moment of the failure but without the failure itself;

Figure 10, shows a FFT analysis of the spectrum of sample records, during work with dedicated endodontic motor, with a programmed number of rpm and torque for rotating or reciprocating NiTi instruments and the failure of the endodontic instrument utilized in the root canal of a suitably prepared freshly extracted human tooth, in a two-dimensional graph;

Figure 11, is a two-dimensional image of the same work as in figures 9 and 10, a few seconds before the failure where features similar to the time of the failure itself were recorded approximately at 10.6 s and 10.9 s;

Figure 12, is the representation of the sound spectrum of the sample records obtained with dedicated motor, with a programmed number of rpm and torque for dental implants with pilot drill on a fresh spongy bovine bone, classified as D4 (softest);

Figure 13, is the representation of the sound spectrum of the sample records obtained with dedicated motor, with a programmed number of rpm and torque for dental implants with pilot drill on a fresh bovine cortical bone, classified as Dl (hardest); here the spectrum displays higher frequency sound waves (denser graph);

Figure 14, shows a FFT analysis of the spectrum during the work in figure 12 (bone classified as Dl);

Figure 15, shows a FFT analysis of the spectrum during the work in figure 13 (bone classified as D4).

With reference to the above mentioned figures, a kit for orthopedic and other kinds of surgery is shown in its complex, particularly for the repair of bone and other kinds of fracture, which has been generally indicated by the reference number 1.

The kit comprises one or more screws 4, suitable for being implanted, each one at an intraosseus implant site 5.

Screws 4 are manufactured by means of a laser sintering process (one suitable manufacturing method is Selective Laser Sintering), which permits manufacturing a screw whose external surface area and internal volume allow a better attachment with the growing bone tissue.

Whenever the circumstances should require it, the kit also provides for the insertion of a stabilization plate 2, which can be applied to a fractured bone 3 by means of screws 4, as shown in figure 2.

The kit also includes a surgical instrument 7 comprising a handpiece 8 provided with a head 9 for the support of a tool 10, a surgical motor 11 for the rotation of the head 9, and an external LED cold light illumination system 19 to illuminate the area of intervention.

There exist straight handpieces 8, as shown by way of example in figure 3, or contra- angle handpieces; regardless of the shape, in any event the handpiece 8 provides a grip 15 transversal to its axis suitable for exercising an incremental axial force^ Handpiece grip 15 may also be double handed. The grip further provides controls 23 for clock-wise rotation, counter clock-wise rotation, and stop. Handpiece 8 is provided with its own lighting system 21 shining light with the same characteristics as external system 19, which however illuminates a restricted area immediately next to the area being perforated in order to avoid reduced visibility caused by potential shadows of the handpiece 8 itself.

Kit 1 further provides a plurality of tools 10 of different size and function, including one or more drill bits of different diameter and/or length to drill a precise hole 6 corresponding to each implant site 5, one or more taps of different diameter and/or length to tap precise threads at each hole 6, and one or more screw-drivers to screw the different types of screw at each threaded hole 6 created.

Motor 11, is provided with detection means of the resisting moment of the bone material being drilled by tool 10 or screw 4, at implant site 5. It further provides rotation speed detection means of the tool (drill or tap). Measuring the instantaneous value of the resisting moment and speed permits calculating the power employed in the drilling and tapping processes.

Monitoring the "power" variable makes estimating the degree of hardness independent from constant speed, and hence speed may be variable, thus obtaining a more versatile instrument that responds optimally when the physical and/or mechanical conditions change during work.

Finally there is a system which enables measuring the temperature of the organic tissues during the drilling, tapping, and screwing procedures.

Kit 1 further provides a means 12 suitable for measuring the sound waves generated by the tool and/or the bone tissue during work. Materials have the property of emitting particular sound waves when being worked and/or perforated, and their mechanical characteristics are being altered. Bone tissue also generates specific sounds during the drilling to create the implant tunnel.

Recognizing the modified characteristics through particular sound waves, which may be part of the audible spectrum or not, may for instance signal the failure of the tool or the bone tissue, and/or validate the degree of hardness and density of the bone, already estimated by the power figure. Preventing the failure in advance permits avoiding damage to the work of the surgeon and ultimately enables the correct implementation of the implant site.

The same principle could be used in endodontic practice when shaping the root canal with rotating NiTi instruments driven by a handpiece attached to a motor. Kit 1 may further be integrated with a cone beam tomography instrument (not displayed in the figures) capable of measuring the shape and direction of the hole while it is being drilled.

Kit 1 further provides a central processing unit 16 suitable for processing the data measured during the utilization of the tools and the data measured by the sensors. More precisely, the processing unit 16 transforms the data acquired during the use of the drill into a first numeric value representing the bone density measured at implant site 5. Furthermore the processing unit 16 transforms the data acquired during tapping into a second numeric value representing bone density, transforms the data acquired during the use of a screwdriver into at least a third numeric value representing the primary stability of screw 4 together with the level of compression of peri-implant vascular bed, and finally transforms the temperature data acquired during all the previous operations into the respective numeric values representing the level of acceptability of the tissue, in order to prevent its degradation.

Kit 1 also comprises a graphical and/or alphanumeric visualization means 17 of the processed data, temperature during the various phases, and the 3D visualization of the hole being drilled in relation to the surrounding bone thickness.

Clearly processing unit 16 is connected on one side to visualization means 17, and on the other to cone beam tomography measurement means. Processing unit 16 is also provided with a storage means (generic electronic media) for the data measured during the entire operation so that they are available to be viewed at a later time upon request.

Processing unit 16 and visualization means 17 are preferably present on a terminal 13 to which the surgical instrument 7 is connected by means of a wire or wireless communication channel 14.

The data sent to the unit 16 include the average power and/or peak power values recorded, and/or the curve representing the trend of the power during the operation of the tool 10, and/or the integral of the curve representing the resisting moment trend. Additional information including the average and/or peak recorded values of the resisting moment, and/or the curve representing the trend of the resisting moment when driving the screw into place, and/or the integral of the curve representing the resisting moment trend.

Visualization means 17 comprises a screen displaying the graph of curve 18 representing the trend of power (Y) during progress (X) of tool 10, while A specifies the present value of progress of the tool measured by the proximity sensor in the handpiece and described in the following (related one to one to the bone layer being crossed), B and C respectively specify the average and peak values of power, and D specifies the value of the integral of the resisting moment curve, so as to provide a visual trace of the work carried out during boring and/or tapping. E specifies the instantaneous temperature measurement related one to one to the progress of the tool. When driving screw 4 into place, the display will show the graph of the curve representing the torque trend (Y) during progress (X) of the screw, while A specifies the present value of the progress of the screw (directly related to the pitch of the threads and the number of turns of the screw, and furthermore related one to one to the bone layer being crossed), B and C respectively specify the average and peak torque value, while D specifies the value of the integral of curve 18. Graphs 18 and values A, B, C, and D are displayed in a color key in order to ease the interpretation of the values: green = acceptable value, yellow = value close to the acceptable limit, red = unacceptable value.

It is possible to transmit some or all of the most significant and timely data to a second display terminal 20 which may be more accessible to the surgeon during the operation. For this purpose said visualization means 20 may comprise a heads up display on the protective helmet of the surgeon, so as to eliminate the need to divert the eyes from the work area in order to view the information on display 17 and/or 20.

In a preferred embodiment, the surgical instrument 7 comprises a chilled sterile saline solution injection system (not shown) in order to lower the temperature of implant site 5. In particular, the injection system is connected to the processing unit 16 to establish a closed loop that automatically engages upon reaching a threshold value in one or more parameters related to the measured power and/or the sound waves and/or the bone density, or which may otherwise be activated or deactivated by the surgeon. An important issue is to obtain bone regeneration by means of "PRP system" or "PRFG" or similar growth factors which permit avoiding the risks of a long recovery period, elevated costs for the patient and the health provider, risk of multiple infections, the advantage of being able to prepare the substance at the clinic at the time of the surgery, avoiding supply errors that may occur when ordering the substance from external laboratories. The growth factors are obtained from a small blood sample from the patient itself before surgery and are injected into the implant site at the end of the threading procedure according to well defined dose parameters; and may additionally contain antibiotic and/or antiseptic solutions.

It is also possible to provide an acoustic warning (not shown) which automatically activates a particular alarm sound upon reaching or exceeding a preset temperature threshold value. In this way the surgeon receives the signal to stop the drilling and/or remove the tool from the bone.

The surgical instrument 7 may comprise a proximity sensor (not shown) to detect the proximity of tissue other than bone during drilling. In particular, said sensor is able to detect the electric potential difference. It is also possible to generate an acoustic alarm signal when the proximity sensor produces a positive signal. In this way the surgeon receives a warning signal to stop the drilling and/or remove the tool from the bone.

The use of the surgical instrument to drill holes 6 and the subsequent implant of screws 4 are illustrated hereinafter.

At least two surgery stages are foreseen (at least one drilling stage and one tapping stage) for drilling a hole 6 in the chosen implant site 5, and at least one surgery stage to insert a screw 4 into the drilled hole 6.

The drilling stage is carried out by engaging handpiece 8 with drilling bit 10.

During progress of drilling through the bone layers the system measures and records the resisting moment of the bone and the speed in order to obtain the drilling power. These data and the acquisition of the sound waves permit calculating the degree of hardness of the bone displayed on display 17 of terminal 13 (and transmitted to display 20 when present) to guide the progress of the surgery the surgeon must adopt in the present drilling stage previous to the other stages.

If the system already detects a moderate degree of hardness in the bone during the initial stage of drilling, it automatically generates and displays a warning message to the surgeon concerning a maximum upper limit for the speed and rotation torque in order to achieve a correct drilling operation. Identifying the degree of hardness of the bone already in the drilling stage also affects the choice of the next surgery stage, which may be an additional drilling stage with a larger diameter drill bit 10, before the tapping stage, or may otherwise affect the choice of tap, or may finally also affect the choice of type of screw to employ and the tightening torque of the same.

In particular provisions can be made so that when the bone is identified to have a low degree of hardness, the system may display a warning message to stop the rotation of tool 10 or reducing its rotation speed, when exceeding a certain rotation speed threshold, in order to prevent creating permanent damage to the implant site. Furthermore, provisions can be made to automatically display a warning message and/or a specific alarm sound for stopping the rotation of tool 10 or reducing the rotation torque when exceeding a certain rotation torque threshold, in order to prevent cavitation of the screw inserted into the implant site.

The tapping stage is carried out by engaging the handpiece 8 with tap 10. During this tapping stage the system processes all the data received to provide the surgeon with the essential information to accurately define the density of the bone tissue and choose the following surgery stages.

The insertion stage is carried out by engaging the handpiece 8 with screw-driver 10. In this insertion stage the system reprocesses graph 18, which supplies to the surgeon the essential information for accurately defining the level of primary stability of the screw, the level of compression exerted by the screw on the vascular bed in the area, and the optimal value of the tightening torque, giving the surgeon the option to accept the value or modify it. In particular, the quality of stability is specified by the average B value of the resisting moment and the integral D of the curve displayed in graph 18, which substantially represents the work carried out by screw-driver 10 to overcome the resistance of the bone tissue.

As shown in figures 5 to 15, by analyzing the sound characteristics recorded during some of the endodontic work stages for some types of bone, the orthopedic surgery kit according to the present invention is capable of intelligently assisting the surgeon and eliminate the human error factor. This further provides for the availability of objective information in connection with the condition of the bone being repaired: the patient may therefore be informed of the post-operative risk that the implant may fail by means of the data stored on the electronic media.

Various modification and variations can be made to the orthopedic surgery kit without departing from the spirit of the present invention. Further, all the details may be replaced by technically equivalent elements.