Orthopedic impact devices

Abstract

An orthopedic impact device comprises an electric motor (3), an actuator (2c), an anvil (4) that can be detachably coupled to a surgical instrument to be inserted or removed, a striking element (5) adapted to interact with the anvil (4) to facilitate the insertion or removal of the surgical instrument, and a motion transmission system (7) adapted to transmit motion from the electric motor (3) to the striking element (5). The anvil (4) has two contact surfaces (4a, 4b) that interact with the striking element (5), the two contact surfaces (4a, 4b) consisting of one first indentation surface (4a) and one second withdrawal surface (4b). The motion transmission system (7) comprises a pusher element (6) adapted to move the striking element (5) by two elastic elements (13) that can selectively amplify the thrust exerted by the striking element (5) on one of the two contact surfaces (4a, 4b) of the anvil (4). The anvil (4) is a hollow cylinder, with a striking element (5) housed inside it, and a pusher element (6) housed inside the striking element (5).

Description

Technical Field

[0001] The present invention relates to an impact device for orthopaedics. In particular, the present invention is mainly used as an auxiliary tool for surgeons during the insertion or removal of surgical tools such as broaches or prostheses inside the femoral canal.

[0002] Such devices are generally portable and battery-driven, mainly aimed at facilitating such operations for surgeons, and are substitutes for conventional hand hammers.

Background Art

[0003] Several impact devices for orthopaedics are known in the market.

[0004] Document EP3162314 describes a battery-driven electrical device that can directly apply thrust in two opposite directions, one direction being used to push in the surgical tool and the other direction being used to remove the surgical tool.

[0005] Functionally, the system consists of a piston moved by a connecting rod and a crank. The piston acts on a chamber in which air is alternately compressed or decompressed. The impact element, which is essentially a second free piston moved by the compressed air generated by the first piston, is the part that actually exerts a mechanical action on the anvil (or an adapter to which a broach or other tool is attached). The mass of the impact element and the speed it obtains result in an energy pulse being transmitted.

[0006] This patent describes several functional modifications, such as the use of valves to control the generated pressure and accordingly vary the magnitude of the impact, or the use of a catch to hold the impact element and release it only when the pressure reaches a high value.

[0007] Instead, to obtain a reverse strike used for removing or, conversely, removing a tool, this patent describes a lever gear actuated by a movable pin struck by a striking element. The striking element then strikes a system of levers, causing the lever to strike a head and apply the necessary reverse pressure to facilitate the removal of the prosthesis or tool.

[0008] Such systems function well, but are nevertheless fragile. This is due to the presence of levers that can break due to the high force of the impact they receive.

[0009] Generally, the systems currently known are difficult to handle, structurally complex and heavy, which makes them unsuitable for surgeons.

[0010] Furthermore, impact forces are not always correctly directed and concentrated to maximize their impulsive effect; rather, they are partially dispersed due to the presence of structural action and motion transmission. Known devices have numerous structural components for motion action, and therefore, in addition to dispersing the transmitted energy, are structurally fragile and prone to failure over time.

[0011] Furthermore, in systems with several mechanical moving parts, the increased vulnerability necessitates applying less force than actually required, resulting in a reduced effectiveness of the blow. Consequently, it becomes necessary to increase the number of blows required to insert or remove the instrument or prosthesis.

[0012] The objective of this invention is to overcome the shortcomings of the prior art.

[0013] In particular, an object of the present invention is to propose an orthopedic impact device that is structurally simple and easy to handle in order to facilitate grasping and use by surgeons.

[0014] Therefore, the object of the present invention is to provide an orthopedic impact device that achieves direct transmission of motion internally, without using linkage mechanisms or joint movements, in order to concentrate the force applied to insert or remove a surgical instrument.

[0015] A further object of the present invention is to provide an orthopedic impact device that can deliver high-energy direct blows, thereby reducing the number of blows required to complete surgery.

[0016] Another objective of the present invention is to provide an orthopedic impact device that shortens surgical time and is durable.

[0017] These objectives and further objectives and benefits are achieved by the orthopedic impact device set forth in the attached claims. [Overview of the Initiative]

[0018] A first aspect of the present invention provides an orthopedic impact device comprising an electric motor, an actuator, an anvil detachably coupled to a surgical instrument to be inserted or removed, a striking element adapted to interact with the anvil to facilitate the insertion or removal of the surgical instrument, and a motion transmission system adapted to transmit motion from the electric motor to the striking element. Advantageously, the anvil has two contact surfaces for interacting with the striking element, the two contact surfaces comprising a first indentation surface and a second withdrawal surface. The motion transmission system comprises a pusher element adapted to move the striking element by two elastic elements capable of selectively amplifying the thrust applied by the striking element to one of the two contact surfaces of the anvil.

[0019] Preferably, the anvil is a hollow cylinder, and the striking element and the pusher element are housed inside it. Advantageously, the pusher element is housed inside the striking element.

[0020] An orthopedic impact device comprises a confinement sleeve, which houses an anvil, a striking element, and a pusher element.

[0021] Preferably, the pusher element, striking element, and anvil are linearly movable in a vibratory motion along the longitudinal axis of the orthopedic impact device.

[0022] The confinement sleeve has a first open end through which an anvil slides and at least partially exits, and a second end connected to the compartment, which houses an electric motor and at least partially a motion transmission system inside.

[0023] The anvil can vibrate along its longitudinal axis within the impact device between a retracted position, where it is fully housed inside the containment sleeve, and an extended position, where it is at least partially outside the containment sleeve.

[0024] The first indentation surface and the second extraction surface are parallel to each other, define the bottom of the cylinder constituting the anvil, and are perpendicular to the longitudinal slide axis. The first indentation surface is located near the first end of the containment sleeve.

[0025] The motion transmission system includes a worm screw that works in cooperation with a nut screw operably coupled to the pusher element to facilitate axial vibration in both directions of movement of the pusher element between a top dead center located near the first end of the confinement sleeve and a bottom dead center located near the second end of the confinement sleeve.

[0026] The striking element is moved by the pusher element and vibrates with it inside the anvil.

[0027] The pusher element, housed within the striking element and sliding axially within it, has a head portion between two elastic elements.

[0028] These elastic elements are a pair of coil springs with the head of the pusher element interposed therebetween, and the axial movement of the pusher element cooperates with the coil springs to generate vibrations along the axis of the striking element.

[0029] The pusher element is connected to the striking element only by the spring.

[0030] The motion transmission system converts the rotational motion of the electric motor into the linear oscillating motion of the pusher element, and the pusher element pulls the striking element along the longitudinal axis in translation by the coil spring. The elastic stretching action of the coil spring can enhance the impact force of the striking element on one of the two abutting surfaces of the anvil, like a slinging effect.

[0031] Advantageously, the direction of this linear oscillating motion is determined by the rotational direction of the worm screw.

[0032] Preferably, the striking element has a cylindrical shape with a first wall parallel to each other defining the bottom of the striking element and a second wall facing the first wall. The first wall of the striking element collides with the first pushing surface of the anvil and pushes the anvil out of the impact device when the anvil is in the retracted position inside the confinement sleeve and the pusher element is at the top dead center.

[0033] The second wall of the striking element collides with the second extraction surface of the anvil and pulls the anvil in, pulling it into the interior of the impact device when the anvil is in a position at least partially withdrawn from the confinement sleeve and the pusher element is at the bottom dead center.

[0034] The pusher element vibrates along the longitudinal axis with a constant movement amplitude inside the confinement sleeve. The interaction and collision of the striking element with the first or second abutting surface of the anvil depend on the position of the anvil relative to the confinement sleeve.

[0035] Orthopedic impact devices also include a pair of springs positioned around the anvil between the outer surface of the anvil and the inner surface of the containment sleeve. The outer springs are adapted to hold the anvil in a neutral position, which is intermediate between the retracted and pulled-out positions.

[0036] Advantageously, the first wall of the striking element has a circular impact surface, and the second wall of the striking element has an annular impact surface. [Brief explanation of the drawing]

[0037] The present invention will become more apparent from the following detailed description with reference to the accompanying drawings provided for illustrative purposes only. [Figure 1] A perspective view of an impact device according to the present invention is shown. [Figure 2] Figure 1 shows a cross-sectional perspective view along the longitudinal plane of an orthopedic impact device. [Figure 3] The side cross-section of the subject of the orthopedic impact device of the present invention, along the longitudinal plane, is shown in a non-operating neutral configuration. [Figure 4] Figure 3 shows a magnified view of the first portion of the cross-sectional view. [Figure 5] Figure 3 shows a magnified view of the second portion of the cross-sectional view. [Figure 6-7] A side cross-section of the subject of the orthopedic impact device of the present invention, along its longitudinal plane, is shown in two different operating steps, namely the removal step in Figure 6 and the insertion step in Figure 7. [Modes for carrying out the invention]

[0038] In the figure above, the orthopedic impact device according to the present invention is shown as 1 overall.

[0039] The orthopedic impact device 1 preferably comprises a confinement casing or case 2 extending along a longitudinal axis 2a, the confinement casing or case 2 housing an energy source 3 such as an electric motor inside.

[0040] In a preferred embodiment shown in the attached drawings, particularly with reference to Figures 1 and 2, the orthopedic impact device 1 has the shape of an electric drill, having a handle 2b with a main central body and an actuator 2c extending along a longitudinal axis 2a.

[0041] As can be seen in Figures 3, 6, and 7, the orthopedic impact device 1 can be divided internally into two parts: a rear section P (shown enlarged in Figure 5) which houses the electric motor 3, and a front section A (shown enlarged in Figure 4) which houses a movable vibrating component adapted to produce an actual impact and shock effect.

[0042] As best seen in Figure 4, the front A contains the containment sleeve 8, and the rear P, best seen in Figure 5, contains a housing compartment 9 for the electric motor 3 and the motion transmission system 7. The containment sleeve 8 and the housing compartment 9 are essentially connected to each other inside the containment casing 2 of the orthopedic impact device in an intermediate zone M along the longitudinal deployment of the orthopedic impact device 1.

[0043] At the front A, the orthopedic impact device 1 includes an anvil 4 which is reversibly coupled to a surgical instrument such as a broach that needs to be inserted into or removed from the human body. The anvil 4 is movable along the longitudinal axis 2a between two extreme positions, namely a first position in which it is fully housed in the containment casing 2, and a second position in which it is at least partially pulled out from the containment casing 2. The anvil 4 exits the containment casing 2 through a first end 8a of the containment sleeve 8.

[0044] Conveniently, Anvil 4 is a hollow cylinder, as will be described later.

[0045] The orthopedic impact device 1 has an open first end 1a through which the confinement sleeve 8 and anvil 4 partially protrude. This first end 1a is therefore oriented toward the surgical instrument to be inserted or removed. The orthopedic impact device 1 also has a second end 1b opposite to the first end, which defines the extent of the posterior zone P.

[0046] The orthopedic impact device 1 further comprises a striking element 5 adapted to interact with the anvil 4 in order to facilitate thrust and traction of the anvil in the manner described later, and thus generally for the insertion or removal of surgical instruments.

[0047] As shown in the attached drawing, the striking element 5 is housed inside the containment casing 2. More specifically, the striking element 5 is housed inside the anvil.

[0048] The orthopedic impact device also includes a motion transmission system 7 adapted to transmit motion from an electric motor 3 to a striking element 5. Specifically, the motion transmission system 7 includes a pusher element 6 that can actuate the striking element 5.

[0049] The striking element 5 is then moved by the pusher element 6, still in an oscillating motion along axis 2a. Both the striking element 5 and the pusher element 6 are of the translational type along the longitudinal axis 2a, which facilitates the thrust of the anvil 4 along the longitudinal axis 2a. Specifically, both the striking element 5 and the pusher element 6 move linearly in an oscillating motion along the longitudinal axis 2a. This motion of the striking element 5 relative to the anvil 4 results in a linear oscillating motion of the anvil 4 itself along the longitudinal axis 2a.

[0050] The electric motor 3 operates the motion transmission system 7, which can transmit motion from the electric motor 3 to the pusher element 6, and thus can operate the striking element 5.

[0051] Motor 3 is advantageously controlled by an electronic circuit board and is activated by pressing a button located on the handle of the impact device itself or by pressing the actuator 2c. The energy supplied is adjusted by adjusting the stroke of button 2c.

[0052] Activation can occur either through a single pulse or through continuous operation based on the duration of button press.

[0053] As previously mentioned, the anvil 4, striking element 5, and pusher element 6 are housed inside the containment casing 2 of the impact device. More specifically, the containment sleeve 8 described above is located inside the containment casing 2 of the impact device, which is positioned at the front A, and the anvil 4, striking element 5, and pusher element 6 are housed in its middle section.

[0054] The confinement sleeve 8 has a first open end 8a through which the anvil 4 slides and at least partially exits, and a second at least partial open end 8b on the opposite side of the first open end.

[0055] The front part A of the orthopedic impact device 1 thus extends along the longitudinal length occupied by the containment sleeve 8, while the rear part P coincides with the housing compartment 9 for the electric motor and motion transmission system 7.

[0056] Referring in detail to Figures 4 and 5, the motion transmission system 7 comprises a worm screw 10 cooperating with a nut screw 11 operably coupled to a pusher element 6. An electric motor 3 actsuates the worm screw 10, which in turn causes the worm screw 10 to rotate on its own about the longitudinal axis 2a, thereby causing the nut screw 11 to translate. The nut screw 11 is confined inside a transmission sheath 14. The transmission sheath 14 is connected to the pusher element 6 and causes its translation along the longitudinal axis 2a in one direction or the other, depending on the direction of rotation of the worm screw 10.

[0057] In this way, the pusher element 6 can vibrate axially in both directions of movement along the longitudinal axis 2a between the top dead center TDC, which is facing the first end 1a of the orthopedic impact device 1 (or the first end 8a of the confinement sleeve 8), and the bottom dead center BDC, which is facing the second end 8b of the confinement sleeve 8.

[0058] The anvil 4 comprises two contact surfaces 4a and 4b, each adapted to interact with the wall of the striking element 5. These two contact surfaces 4a and 4b constitute a first indentation surface 4a and a second withdrawal surface 4b, respectively, located forward and close to the first open end 8a of the confinement sleeve 8, and thus close to the first end 1a of the orthopedic impact device 1. The first indentation surface 4a passes through the open end of the sleeve and the orthopedic impact device. The withdrawal surface 4b, on the other hand, is located near an intermediate zone M close to the second end 8b of the confinement sleeve 8. The two contact surfaces 4a and 4b are parallel to each other, located at both ends of the anvil 4, and perpendicular to the longitudinal axis 2a of translational motion passing through their center points. The anvil 4 preferably has a cylindrical shape, and the aforementioned contact surfaces define the end walls of this cylinder.

[0059] Advantageously, the indentation surface 4a has a solid circular shape and is equipped with a pin 12 that protrudes outward axially away from the anvil. This pin 12 allows for connection to a surgical instrument or prosthesis.

[0060] Instead, the extraction surface 4b has a substantially annular shape because it is necessary to secure space in the center for the motion transmission system 7, particularly the screw 10 and the sheath 14, to pass through.

[0061] The striking element 5 comprises a first wall 5a or front wall and a second wall 5b or rear wall opposite the first wall. Advantageously, the striking element 5 is hollow inside.

[0062] The striking element 5 preferably has a cylindrical shape.

[0063] The walls of the striking element 5 also have a circular shape at the front, so that the first wall 5a facing the first end 1a of the impact device and interacting with the pressing surface 4a of the anvil is circular, while the rear or second wall 5b has an annular shape, leaving the central zone open for the passage of the motion transmission system 7. The first wall or front wall 5a of the striking element 5 interacts with and collides with the pressing surface 4a of the anvil 4, while the second wall or rear wall 5b of the striking element 5 interacts with and collides with the withdrawal wall 4b of the anvil 4.

[0064] The striking element 5 is housed inside the anvil 4, just as the pusher element 6 is floating and housed inside the striking element 5.

[0065] In other words, the anvil 4 is a hollow cylinder containing the striking element 5, and the pusher element 6 contains the striking element 5, and these are nested within each other. The anvil 4, striking element 5, and pusher element 6 are coaxial, concentric, and interlocked with each other.

[0066] The pusher element 6 floats within the striking element 5 between two elastic elements 13 that amplify the thrust of the striking element 5 against the anvil 4, as will be described later.

[0067] The anvil 4 can vibrate and translate along the longitudinal axis 2a within the containment casing or case 2 of the impact device. Specifically, the anvil 4 can vibrate and translate along the longitudinal axis 2a within the containment sleeve 8 between a fully retracted position (Figure 7) in which it is completely housed inside the orthopedic impact device 1, and an extended position (Figure 6) in which it is at least partially outside the orthopedic impact device 1.

[0068] As shown in Figure 7, when the surgeon presses the impact device 1 against the patient and therefore against the surgical instrument to be inserted, the anvil 4 is in a fully retracted position (and therefore fully inserted into the sleeve 8). The first wall 5a of the impact element 5 strikes the pressing surface 4a of the anvil 4. Both of these are located near the first end 1a of the orthopedic impact device 1. The first wall 5a of the impact element 5 acts as a kind of hammer against the anvil 4, and therefore the anvil 4 is pushed out of the confinement sleeve 8, thereby pushing the surgical instrument through its connection with the connecting pin 12. In this way, the insertion of the instrument itself into a predetermined position inside the human body is facilitated.

[0069] In contrast, as shown in Figure 6, when a surgical instrument is to be removed, the surgeon pulls the impact device toward himself, away from the patient, and at least partially pulls out the anvil 4, which is connected to the surgical instrument inserted into the human body via a pin 12. The relative translational motion between the anvil and the sleeve of the impact device pulls the impact device away from the human body, causing the anvil 4, connected to the instrument to be removed from the human body, to at least partially exit the sleeve 8. In this pulled-out position, or at least partially pulled-out position of the anvil (Figure 6), the second wall 5b of the striking element 5 begins to interact with and act on the removal surface 4b of the anvil as a result. By impacting the anvil 4, the striking element 5 pulls the anvil 4 toward the inside of the impact device 1, which then facilitates the removal of the surgical instrument connected to it by the pin 12. In other words, the pushing action of the striking element against the removal surface 4b of the anvil is similar to the pushing action of a hammer, but acts in the opposite direction to the insertion direction described in the previous situation in Figure 7, and therefore acts for removal. The surgical instrument is thus pulled in by the pin 12 connected to the anvil 4. The anvil 4 is pulled away from the human body, and as a result, the surgical instrument is removed.

[0070] The motion transmission system 7 includes and is connected to a pusher element 6, which can be considered to be floating in the sense that it is held in an elevated position by the worm screw 10 and especially by the transmission sheath 14, without being directly connected to the striking element 5.

[0071] The striking element 5 is moved by the pusher element 6 and vibrates together inside the anvil 4.

[0072] In fact, the pusher element 6 is connected to the striking element 5 by two elastic elements 13, which can amplify the thrust of the pusher element 6 exerted on the striking element 5, and thus selectively amplify the impact force of the striking element 5 to one of the two contact surfaces 4a and 4b of the anvil 4, depending on whether the tool is inserted or removed.

[0073] In particular, the pusher element 6 is housed inside the striking element 5 and slides axially within it, and has a head 6a between the aforementioned elastic elements 13.

[0074] In other words, the two elastic elements 13 and the pusher element 6 are housed inside the striking element 5.

[0075] These elastic elements 13 are preferably a pair of coil springs, with the aforementioned head 6a of the pusher element interposed between them.

[0076] The first spring 131 is positioned between the first end 5a of the striking element 5 and the head 6a of the pusher element 6, and the second spring 132 is positioned between the head 6a and the second end 5b of the striking element; both are located inside the striking element 5.

[0077] The axial movement of the pusher element 6 works in cooperation with the coil springs 131 and 132 to generate vibrations of the striking element 5 along the longitudinal axis 2a. The pusher element 6 is connected to the striking element 5 only via the two coil springs 131 and 132.

[0078] Therefore, the rotation of the electric motor 3 and the worm screw 10 is converted into translational motion of the pusher element, and thus the striking element 5, via the nut screw 11 and the transmission sheath 14. The elastic stretching action of the coil springs 131 and 132 can amplify the impact force of the striking element 5 against one of the two contact surfaces 4a or 4b of the anvil 4, similar to a sling effect.

[0079] The translational motion of the striking element exhibits oscillating motion in both directions along the longitudinal axis 2a as a result of the reversal of the rotational direction of the worm screw 10.

[0080] The vibration of the pusher element 6 inside the confinement sleeve 8 has a constant displacement amplitude. That is, the interaction and collision of the striking element 5 with the first contact surface 4a or the second contact surface 4b of the anvil 4 depends on the position of the anvil 4 relative to the confinement sleeve 8.

[0081] The impact device 1 further includes additional elastic elements 15 positioned around the anvil 4 within a gap 16 provided between the anvil 4 and the confinement sleeve 8, particularly between the outer surface 4e of the anvil 4 and the inner surface 8i of the confinement sleeve 8.

[0082] These additional elastic elements 15 preferably consist of a pair of coil springs 151 and 152 separated by annular partitions 17 that project radially from the outer surface of the anvil 4.

[0083] The first spring 151 is located between the front shoulder 81 of the sleeve 8 and the bulkhead 17, and the second spring 152 is located between the bulkhead 17 and the rear shoulder 82 of the sleeve 8.

[0084] These coil springs 151 and 152, positioned around the anvil 4, serve to hold the anvil 4 in a neutral position where no interaction occurs between the striking element 5 and the anvil 4 (as shown in Figure 3).

[0085] Advantageously, sensors are also provided that are not shown in the figures but can detect the position of the anvil and actuate a motor to rotate the screw in one direction or the other, thereby actinguating the striking element in one direction or the other.

[0086] The following situations may occur during use.

[0087] The situation of inserting surgical instruments into the human body.

[0088] Starting from the neutral position of the anvil (as can be seen in Figure 3), in which the outer coil springs 15 positioned around the anvil 4 hold the anvil in an intermediate position between the retracted insertion position and the pulled-out removal position, the surgeon pushes the impact device by pressing the broach, which is engaged with the pin 12, against the bone.

[0089] The anvil then retracts, moving from an intermediate position to a fully retracted position (Figure 7) where it is inserted into the sleeve 8. In fact, under the pressure applied to the impact device by the surgeon, the second coil spring 152 is compressed, thus causing the anvil to reach the retracted position and enabling the thrust or contact of the striking element against the anvil's recessed surface. In fact, at this fully retracted position inside the sleeve, the sensor detects the anvil's position and sends a signal to the motor, which acts to activate the motion transmission system, which then acts the striking element and releases the movement of the entire device. Since the anvil is in the fully retracted position, inserted into the confinement sleeve, the striking element interacts with the anvil by bringing its first surface into contact with the anvil's first surface. Both are positioned facing the first open end of the impact device (Figure 7).

[0090] Then the instrument is inserted.

[0091] If the surgeon wishes to interrupt the thrust, they release the pressure against the bone, and the anvil returns to its neutral position. Sensors detect the anvil's new position, and the striking mechanism stops.

[0092] To remove the instrument, the entire impact device needs to be pulled in or retracted. The surgeon pulls the device towards himself to remove the broach, which extends the second coil spring 152, and since the broach is trapped in the bone, the anvil is also pulled outward (Figure 6). This is because the broach tries to remain fixed to the bone.

[0093] The sensor thus releases the movement of the striking mechanism, which has been given an outward-advancing position for the anvil, and the withdrawal continues. Since the anvil is in a position that is at least partially withdrawn, the striking element strikes the second contact surface of the anvil with its second contact surface. Both surfaces are positioned toward the intermediate zone of the orthopedic impact device (Figure 6).

[0094] The present invention achieves its intended purpose by providing an orthopedic impact device that is extremely easy to handle, lightweight, structurally simple, and robust, thanks to its internal motion mechanism that lacks linkages that would otherwise make the structure fragile.

[0095] The subject of the impact device of the present invention is that, thanks to the presence of elastic supports such as two coil springs, it is possible to apply a considerable impact force in a constant and concentrated manner without energy dissipation, and the elastic supports increase and enhance the impact force of the selective impact element against the pushing or pulling surface as they dynamically amplify the velocity of the impact element during the impact step. The velocity of the pusher element follows a profile established and optimized to maximize impact performance.

[0096] In this way, it is also possible to reduce the number of blows that need to be delivered to complete the necessary surgery.

[0097] The described orthopedic impact device makes surgical procedures simpler and easier for surgeons by replacing the traditionally used hammer with a handle.

[0098] The impact device in question is equipped with a battery-powered electric motor that releases energy, causing the device to apply selectively controlled forces to the two impact surfaces of the anvil, thereby creating a precise impact at its ends. This impact acts alternately in two opposing directions depending on the relative position between the anvil and the impact device, thus generating an insertion or extraction force. [Prior art documents] [Patent Documents]

[0099] [Patent Document 1] EP3162314

Claims

1. An orthopedic impact device comprising an electric motor (3), an actuator (2c), an anvil (4) that can be detachably coupled to a surgical instrument to be inserted or removed, a striking element (5) adapted to interact with the anvil (4) to facilitate the insertion or removal of the surgical instrument, and a motion transmission system (7) adapted to transmit motion from the electric motor (3) to the striking element (5), The anvil (4) has two contact surfaces (4a, 4b) that interact with the striking element (5), The two contact surfaces (4a, 4b) are composed of one first pressing surface (4a) and one second extraction surface (4b), The motion transmission system (7) includes a pusher element (6) adapted to move the striking element (5) by two elastic elements (13) that can selectively amplify the thrust applied by the striking element (5) to one of the two contact surfaces (4a, 4b) of the anvil (4), An orthopedic impact device, wherein the anvil (4) is a hollow cylinder inside, the impact element (5) is housed inside the anvil (4), and the pusher element (6) is housed inside the impact element (5).

2. The orthopedic impact device according to claim 1, comprising a confinement sleeve (8) in which the anvil (4), the striking element (5), and the pusher element (6) are housed.

3. The orthopedic impact device according to claim 1 or 2, wherein the pusher element (6), the striking element (5), and the anvil (4) are linearly movable by vibration motion along the longitudinal axis (2a) of the orthopedic impact device (1).

4. The orthopedic impact device according to claim 2, wherein the confinement sleeve (8) has a first open end (8a) through which the anvil (4) slides and exits at least partially, and a compartment (9) through which a second end (8b) connected to the compartment (9) houses the electric motor (3) and at least partially the motion transmission system (7).

5. The orthopedic impact device according to claim 2, wherein the anvil (4) can vibrate within the impact device along the longitudinal axis (2a) of the orthopedic impact device between a retracted position in which it is fully housed within the confinement sleeve (8) and an extended position in which it is at least partially outside the confinement sleeve (8).

6. The orthopedic impact device according to claim 5, wherein the first pressing surface (4a) and the second withdrawal surface (4b) are parallel to each other, define the bottom of the cylinder constituting the anvil (4), and are perpendicular to the longitudinal axis (2a) of the slide, and the first pressing surface (4a) is located near the first end (8a) of the confinement sleeve (8).

7. The orthopedic impact device according to claim 2, wherein the motion transmission system (7) comprises a worm screw (10) cooperating with a nut screw (11) operably coupled to the pusher element (6) to promote axial vibration in both directions of movement of the pusher element (6) between a top dead center (TDC) located near the first end (8a) of the confinement sleeve (8) and a bottom dead center (BDC) located near the second end (8b) of the confinement sleeve (8).

8. The impact element (5) is moved by the pusher element (6) and vibrates together with it inside the anvil (4), as described in any one of claims 1 to 7.

9. The orthopedic impact device according to claim 8, wherein the pusher element (6) is housed inside the impact element (5) and slides axially therein, and the pusher element (6) has a head portion (6a) between the two elastic elements (13).

10. The orthopedic impact device according to claim 9, wherein the elastic element (13) is a pair of coil springs (131, 132) with the head portion (6a) of the pusher element (6) interposed between them, and the axial movement of the pusher element (6) cooperates with the coil springs (131, 132) to generate vibration along the axis of the impact element (5).

11. The orthopedic impact device according to claim 10, wherein the pusher element (6) is connected to the impact element (5) only by the coil springs (131, 132).

12. The motion transmission system (7) converts the rotational motion of the electric motor (3) into linear vibrational motion of the pusher element (6), the pusher element (6) pulls the striking element in translation along the longitudinal axis (2a) by the coil springs (131, 132), the elastic stretching action of the coil springs (131, 132) can enhance the impact force of the striking element (5) against one of the two contact surfaces (4a, 4b) of the anvil (4), as described in any one of claims 1 to 11.

13. The orthopedic impact device according to claim 7 or 12, wherein the direction of the linear vibration motion is determined by the rotation direction of the worm screw (10).

14. The impact element (5) has a cylindrical shape with a first wall (5a) and a second wall (5b) opposite to the first wall that define the bottom of the impact element (5), wherein the first wall (5a) of the impact element collides with the first pushing surface (4a) of the anvil (4) when the anvil (4) is in a retracted position inside the confinement sleeve (8) and the pusher element (6) is at top dead center (TDC), pushing the anvil (4) out of the impact device, as described in claim 2.

15. Orthopedic impact device according to claim 14, wherein when the anvil (4) is at least partially withdrawn from the confinement sleeve (8) and the pusher element (6) is at the bottom dead center (BDC), the second wall (5b) of the striking element (5) collides with the second withdrawal surface (4b) of the anvil (4), pulling the anvil (4) inward and into the impact device.

16. The orthopedic impact device according to any one of claims 1 to 15, wherein the pusher element (6) vibrates along the longitudinal axis (2a) with a constant amplitude of movement inside the confinement sleeve (8), and the interaction and collision of the impact element (5) with the first contact surface (4a) or the second contact surface (4b) of the anvil (4) depends on the position of the anvil (4) relative to the confinement sleeve (8).

17. An orthopedic impact device according to claim 2, comprising a pair of springs (151, 152) positioned around the anvil (4) between the outer surface (4e) of the anvil (4) and the inner surface (8i) of the confinement sleeve (8), wherein the outer springs (151, 152) are adapted to hold the anvil (4) in a neutral position intermediate between the retracted and pulled-out positions.

18. The orthopedic impact device according to claim 14, wherein the first wall (5a) of the impact element (5) has a circular impact surface, and the second wall (5b) of the impact element (5) has an annular impact surface.

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