MEDICAL INSTRUMENT WITH IMPROVED HAPTIC HANDLING

Description

[0001] The present invention relates to a medical instrument, in particular for arthroscopic interventions in the knee, hip or ankle, which enables simplified handling and has improved haptic properties.

[0002] Medical instruments for arthroscopic procedures are known in various designs from the prior art. The medical instrument typically comprises a handpiece and a blade holder. The handpieces are connected to a drive or have a drive so that cutting instruments can be driven in rotation in the blade holder to remove tissue or other biological material, particularly from a joint area. Such medical instruments typically also have a suction device for sucking out severed material, which is passed through the medical instrument. Furthermore, the blade holder is detachably attached to the handpiece to enable appropriate cleaning of the parts of the medical instrument. The detaching and reconnecting of the handpiece and blade holder should be as quick, easy, and safe as possible.Such a connection arrangement is known, for example, from EP 1 790 292 A1. However, this connection arrangement comprises a relatively large number of parts and is relatively difficult to clean after use. Furthermore, optimal handling by a surgeon during an operation must also be possible. During the operation, the surgeon usually does not look at the hand in which he is holding the medical instrument. To operate the medical instrument, the handpiece is usually equipped with several individual buttons which the surgeon must press with a finger, often with the thumb, in order to rotate the medical instrument counterclockwise or clockwise or to perform suction. Incorrect operation by pressing the wrong button could lead to undesirable results during the operation.Since the handpieces are reused after an operation, residue-free cleaning of the handpieces must also be ensured. WO 2006 / 12558 A1 discloses an instrument with a rocker switch in which a first or second contact can be actuated by rocking about a rocker axis, or both contacts can be actuated simultaneously by moving the rocker axis. FR 2 368 790 A1 further discloses a switch in which three sensors can be actuated separately. Furthermore, JP 2004-179 047 A discloses a button switch which can contact one of three contacts by pivoting a button holder connected to a button. EP 2 564 795 A1, US 2008 / 287925 A1 and US 6 500 169 B1 describe medical devices with a handpiece having three buttons. The buttons are arranged independently in a row at a distal end.

[0003] It is therefore an object of the present invention to provide a medical instrument which, with a simple structure and simple, cost-effective manufacture, enables safe and simple operation and makes particularly simple and quick cleaning possible.

[0004] This object is achieved by a medical instrument having the features of claim 1. The subclaims show preferred developments of the invention.

[0005] The medical instrument for arthroscopic procedures with the features of claim 1 has the advantage that haptic perception for a user of the medical instrument is significantly improved. In particular, the medical instrument according to the invention is suitable for being operated with only one finger, preferably with one thumb of the user. The instrument according to the invention provides the user with optimal feedback when a button on the handpiece is pressed. This is achieved according to the invention in that a button arrangement for actuating the medical instrument is provided, which is located near a distal end of the handpiece, at which a cutting edge holder is arranged on the handpiece. The button arrangement comprises three buttons, but only two touch contacts. A first button is configured to actuate a first touch contact.A second button is configured to actuate a second touch contact. A third button is configured to actuate the first and second touch contacts simultaneously. The medical instrument thus has a significantly simplified structure because there is not one touch contact for each button, but rather two touch contacts can be actuated in different ways using three buttons. Furthermore, the arrangement of the button arrangement near the distal end of the handpiece, at which the cutting edge holder, which has an outer hollow tube and an inner hollow cutting edge tube with cutting edges at a distal end of the inner tube, can be reached, so that the medical instrument lies very well in the hand. The medical instrument is very well balanced in the user's hand, so that in particular the button arrangement can be operated easily and safely using the user's thumb.

[0006] Furthermore, the keys are arranged on a common, rigid keyplate. This not only allows for particularly simple and cost-effective manufacturing, but also offers significant advantages in terms of cleaning, as there are fewer gaps and cracks between the keys. The rigid keyplate has the further advantage of easily ensuring that both key contacts can be actuated simultaneously using the third key. The rigid keyplate is preferably made of metal, especially stainless steel.

[0007] Furthermore, the rigid key plate is loosely arranged on the first and second key contacts. The rigid key plate is held on its axial longitudinal sides to a lid, cover, or the like, with a projecting portion of the key plate engaging behind an undercut in the lid.

[0008] Particularly preferably, the three buttons of the button arrangement are arranged in a row in the axial direction of the handpiece. The third button, which is configured to simultaneously actuate the first and second button contacts, is arranged between the first and second buttons. As a result, the three buttons are positioned very compactly on the handpiece, making operation very simple. The button arrangement is particularly preferably arranged on an upper side of the handpiece. As a result, the handpiece can be held in the hand such that the thumb is positioned on the upper side of the handpiece in the area of ​​the button arrangement and the underside of the handpiece rests on the user's remaining fingers and can be held securely.

[0009] Particularly preferably, the rigid keyplate has specially designed keys formed on an upper side of the rigid keyplate. The rigid keyplate has a first raised area on the first key at a distal end of the keyplate. The second key has a second raised area at a proximal end. Furthermore, the third key, which is located midway between the first and second keys, has a third raised area. By providing the raised areas, the three keys of the keyplate can be easily and reliably located and actuated accordingly.

[0010] Particularly preferably, the first key tapers towards the third key and the second key also tapers towards the third key. This means that the key plate has raised areas at both ends and the third raised area is provided in the middle area of ​​the third key. Starting from the raised area of ​​the first key, a user can feel that the first key tapers towards the middle, then the next raised area is the third key with the third raised area. By moving the thumb further towards the second key, the user can first feel the end of the third key and then the gradual rise up to the second raised area of ​​the second key. This ensures that the three keys can be operated safely and easily without looking.

[0011] Preferably, in the unactuated state, a distance of the first raised region, the second raised region and the third raised region from a central axis of the medical instrument is the same.

[0012] According to a further preferred embodiment of the invention, the medical instrument further comprises a control board integrated into the key arrangement. The control board is preferably arranged below the rigid key plate. The first and second key contacts are arranged between the rigid key plate and the control board. Reset elements are preferably arranged between the key contacts and the control board. The control board is preferably designed such that contact areas are provided on a surface of the control board, which contact areas can be contacted by actuating the key plate in order to enable corresponding control commands, in particular a rotating drive of the inner cutting tube.

[0013] Particularly preferably, the button assembly comprises a first and a second reset element. The two reset elements are arranged on the first and second pushbutton contacts, respectively, and enable the button assembly to be reset to a non-actuated initial position. The reset elements are preferably arranged below the pushbutton contacts. The reset elements are particularly preferably snap-action discs, preferably made of spring steel.

[0014] The first and second return elements are preferably each a resilient snap-action disc, which, upon deformation, generates an acoustic signal, such as a click, so that a user also receives acoustic feedback regarding the pressing of a button. The snap-action disc also generates an acoustic signal upon its return to its original position.

[0015] The third key on the rigid keyplate is preferably designed as a small cylindrical protrusion on the keyplate. The third key is preferably button-shaped.

[0016] Further preferably, the rigid key plate has a symmetrical constriction in the axial direction in the region of the third key. The width of the rigid key plate is smaller in the region of the third key than in the region of the first and second keys. This further simplifies the user's ability to identify where their finger is currently positioned.

[0017] Furthermore, the medical instrument has the advantage that a cutting edge holder can be quickly and easily detached from a handpiece and quickly connected to the handpiece. Furthermore, both the handpiece and the cutting edge holder can be cleaned very easily and thoroughly in a short time. This is achieved because the medical instrument has a connecting arrangement for detachably connecting the handpiece to the cutting edge holder. The cutting edge holder comprises an outer tube and an inner tube with cutting edges at the distal end. The connecting arrangement has two arms extending in the axial direction of the medical instrument and arranged on the cutting edge holder. The arms lie opposite one another and have a locking element at their free ends. Furthermore, the arms each have a pressing area for actuation and an elastic area.The handpiece has a receptacle with an undercut for the locking elements on an inner circumference. In addition, the handpiece has two recesses at a distal end region, which serve to partially accommodate the arms. The locking elements and the undercut provide axial securing of the cutting edge holder to the handpiece. The two recesses at the distal end region of the handpiece and the regions of the arms arranged in the recesses provide anti-twist protection. Thus, the connection arrangement according to the invention between the handpiece and the cutting edge holder not only provides axial securing but also anti-twist protection. The number of parts in the connection arrangement is very small. Furthermore, the parts of the connection arrangement can be cleaned quickly and easily. This makes the connection arrangement particularly suitable for use with reusable cutting edge holders.However, since the connection arrangement can also be manufactured relatively inexpensively, for example from a plastic, the connection arrangement is also suitable for use with disposable instruments.

[0018] Preferably, the pressing areas protrude radially outward from the arms. The pressing areas particularly preferably protrude outward from an outer circumference of the handpiece in the region of the connecting arrangement, thus enabling simple actuation, in particular for releasing the cutting edge holder from the handpiece.

[0019] More preferably, the locking elements on the arms have a ramp. The ramp preferably has an angle of ≤ 45°. This allows for a particularly simple connection through a relative axial displacement between the cutting edge holder and the handpiece, so that the cutting edge holder can be easily placed on the handpiece and moved in the axial direction. The arms then slide along the ramps in an interior area of ​​the handpiece and engage resiliently behind the undercut on the handpiece.

[0020] Further preferably, the arms are formed integrally with a ring, with the elastic region of the arms located between the ring and the pressing regions. This allows the connecting arrangement to be attached to the cutter holder by means of the ring, and the arms only need to perform the functions of anti-twist and axial locking.

[0021] The ring to which the arms are attached is preferably detachably connected to the blade holder by means of a clip connection. This also makes it possible for the ring, including the arms, to be detached from the blade holder, allowing separate cleaning of the blade holder and this part of the connecting arrangement with the ring and arms.

[0022] The recesses in the handpiece for accommodating parts of the arms are preferably U-shaped. The arms have U-shaped sections corresponding to the recesses, particularly in the pressing areas of the arms.

[0023] Further preferably, the button arrangement is arranged circumferentially between the recesses for receiving the arms of the connecting arrangement. This enables a particularly compact design of the medical instrument, particularly in the axial direction.

[0024] This key layout design allows for a significant structural simplification of the key arrangement. Two key contacts can be actuated differently by three keys, enabling three operating states of the medical instrument with just two key contacts. For example, the first key is configured for clockwise rotation of the medical instrument, the second key is configured for anticlockwise rotation of the medical instrument, and the third key is configured for an oscillating movement of the medical instrument in a left-to-right direction. The rigid key plate is positioned above the first and second key contacts. The rigid key plate is preferably tiltable about a tilt axis perpendicular to the central axis XX of the medical instrument.

[0025] More preferably, the medical instrument further comprises a suction control arranged on the handpiece in line with the button arrangement. This allows the medical instrument to be used in one-handed operation, while simultaneously actuating the cutting instrument in the appropriate direction and regulating the suction of severed tissue.

[0026] The medical instrument is preferably used in joint surgery or meniscus surgery or other endoscopic procedures.

[0027] A preferred embodiment of the invention will be described in detail below with reference to the accompanying drawings. In the drawing: Fig. 1 is a schematic, perspective view of a medical instrument according to a preferred embodiment of the invention, Fig. 2 is a schematic, perspective exploded view of a button arrangement of the medical instrument of Fig. 1 , Fig. 3 a schematic plan view of the key arrangement, Fig. 4 a schematic sectional view along the line IV-IV of Fig. 3 , Fig. 5 a schematic longitudinal sectional view through the button arrangement in the unactuated state, Fig. 6 a schematic longitudinal sectional view of the button arrangement in an actuated state, Fig. 7 a schematic sectional view through a handpiece of the medical instrument of Fig. 1 , Fig. 8 a schematic view of the cutting edge holder with a part of the connecting arrangement for connection to the handpiece, and Fig. 9 a schematic, perspective view of the part of the connecting arrangement arranged on the cutting edge holder.

[0028] The following is based on the Fig. 7 to 9 a medical instrument 1 for arthroscopic procedures according to a first preferred embodiment of the invention is described in detail.

[0029] As from Fig. 1 As can be seen, the medical instrument 1 comprises a handpiece 2 and a blade holder 3.

[0030] In the handpiece 2, for example, a drive is arranged in the cavity 22 or alternatively the handpiece can be connected to a drive.

[0031] The cutting edge holder 3 comprises an outer hollow tube 30 and an inner cutting edge tube 31 with cutting edges 32 at a distal end.

[0032] Furthermore, a part of a connecting arrangement 4 is arranged on the cutting edge holder 3. The connecting arrangement 4 is shown in detail in the Fig. 7 to 9 visible.

[0033] As is particularly evident from Fig. 9As can be seen, the part of the connection arrangement 4 arranged on the cutting edge holder 3 comprises a ring 46, from which two arms 40 protrude in the axial direction XX of the medical instrument. The two arms 40 are located opposite one another on the ring 46. The ring 46 comprises a clip connection 47 with which the ring can be clipped onto the cutting edge holder 3. The ring 46 is thus detachably arranged on the cutting edge holder 3.

[0034] The two arms 40 are constructed identically and have a locking element 41 at a distal end, a pressing area 42 for actuation and an elastic area 43. The elastic area 43 is arranged in the axial direction XX between the pressing area and the ring 46. The pressing area 42 is a solid body area which projects radially outwards on the arms 40. As can be seen in particular from the Fig. 1 and 3As can be seen, the pressing areas 43 thus protrude laterally from the medical instrument 1. This allows easy gripping and actuation of the pressing areas to release the blade holder 3 from the handpiece 2.

[0035] How to continue Fig. 7 As can be seen, the connection arrangement 4 in the handpiece 2 in a hollow handpiece body 20 further comprises a receptacle 44 with an undercut 44a. The undercut 44a runs as a groove-shaped depression along the inner circumference of the hollow handpiece and comes into contact with the locking elements 41 when the cutting edge holder 2 is mounted on the handpiece 2. The locking elements 41 each have ramps 41a, so that a connection can be established by simply sliding the cutting edge holder 3 axially onto the handpiece 2.

[0036] Furthermore, two U-shaped recesses 45 are formed in the handpiece body 20. The recesses 45 serve to accommodate the pressing areas 42. The two recesses 45 also serve as a guide area during the sliding process of the cutting edge holder 3 onto the handpiece 2.

[0037] When the cutter holder 3 is mounted on the handpiece 2, the pressure areas 42 are accommodated in the recesses 45 and protrude radially outward beyond the handpiece 2. Thus, the pressure areas 42, in conjunction with the recesses 45, form a rotation lock for the cutter holder 3 relative to the handpiece 2. The locking elements 41, which are engaged at the undercut 44a, form an axial lock for the cutter holder 3 on the handpiece 2.

[0038] Thus, a twist-proof connection can be realized between the blade holder 3 and the handpiece 2. Since the connecting assembly 4 is also removable from the blade holder 3, particularly easy cleaning of the parts of the medical instrument is also possible.

[0039] The connecting arrangement 4, which is arranged on the blade holder 3, is preferably a plastic part. The protrusion of the pressing areas 42 from the arms 40 also allows for simple and safe operation by a user of the medical instrument.

[0040] Furthermore, a suction channel 21 is provided in the handpiece body 20, through which suctioned tissue, which emerges from the blade holder 3 through an outlet opening 33, can be removed.

[0041] A button arrangement 5 for actuating the medical instrument is also arranged on the handpiece 2. The button arrangement 5 comprises a first button 51, a second button 52, and a third button 53. As can be seen from Fig. 1 and 3 As can be seen, the three buttons 51, 52, 53 are arranged in a row in the axial direction XX of the medical instrument. Button arrangement 5 is positioned at a distal end of the handpiece 2, close to the transition to the cutting edge holder 3.

[0042] The first, second and third keys 51, 52, 53 are integrated on a rigid key plate 50, preferably made of stainless steel. Fig. 2 and 3As can be seen, the key plate 50 is elongated and lies above a first key contact 55 and a second key contact 56. Between the two key contacts 55, 56 is a tilt axis YY of the key arrangement. The tilt axis YY is perpendicular to the axial direction XX of the medical instrument 1. The three keys 51, 52, 53 are thus key areas on the rigid key plate 50.

[0043] The key assembly 5 further comprises a cover 57, which partially protects the key plate and in particular the key contacts 55, 56 from external influences. As can be seen from Fig. 2As can be seen, two lateral recesses 59 are provided in the cover 57, which extend in the axial direction XX. Two lateral projections 58 are provided on the key plate 50, which also extend in the axial direction XX and, when assembled, engage in the lateral recesses 59 in the cover 57. This secures the key plate 50 in the vertical direction perpendicular to the axial direction XX and also in the axial direction XX.

[0044] Furthermore, a control board 6 is integrated into the button arrangement 5 below the first and second pushbutton contacts 55, 56. This makes it possible for electronic control elements on the control board 6 to be directly activated by actuating the first and / or second pushbutton contacts 55, 56 in order to control the medical instrument 1.

[0045] The key arrangement 5 thus comprises only exactly the two pushbutton contacts 55, 56. The first pushbutton contact 55 is arranged below the first button 51 and the second pushbutton contact 56 is arranged below the second button 52. Thus, by pressing the first button 51, the first pushbutton contact 55 can be activated and by pressing the second button 52, the second pushbutton contact 56 can be activated. As can be seen from Fig. 1 and 5 As can be seen, the third button 53 is arranged between the first button 51 and the second button 52. The button device 5 is now configured such that by pressing the third button 53, both button contacts 55, 56 are actuated jointly by means of the rigid button plate 50.

[0046] Fig. 5 shows the inoperative state of the key arrangement 5. The rigid key plate 50 rests loosely on the first and second key contacts 55, 56. As can be seen in particular from the Figs. 5 and 6As can be seen, a reset element is arranged between the control board 6 and the first and second pushbutton contacts 55, 56. More precisely, a first reset element 7 is arranged below the first pushbutton contact 55, and a second reset element 8 is arranged below the second pushbutton contact 56. The two reset elements 7, 8 are designed as snap-action discs, which, when actuated, press directly onto the control board 6 and accordingly close a contact on the control board 6.

[0047] Fig. 6 shows the state in which the first button 51 is pressed. A user presses, as indicated by the arrow A in Fig. 6 indicated, on the first key 51, whereby the first key contact is moved towards the control board 6 and the first return element 7 is deformed to establish contact with the control board. Since the key plate 50 is rigid, as shown in Fig. 6indicated by arrow B, the second key 52 moves in the opposite direction from the second key contact 56. The rigid key plate 50 pivots about the tilt axis YY.

[0048] To protect and seal the control board 6, a first housing 11 is provided on the first push button 55 and a second housing 12 is provided on the second push button 56. The two housings 11, 12 are connected by means of a holding plate 13 (see in particular Fig. 2) is held on the handpiece body 20. The first and second housings 11, 12 have a substantially cylindrical guide region in which the first and second pushbutton contacts 55, 56, which are cylindrical components in this exemplary embodiment, are arranged. A seal (not shown) is formed between the cylindrical pushbutton contacts 55, 56 and the cylindrical housing parts of the first and second housings 11, 12. The control board 6 can thus be protected from the environment in a fluid-tight manner in a simple manner, so that even during cleaning in an autoclave or using other cleaning techniques, no damage to the button arrangement 5 and the control board 6 occurs.

[0049] As is particularly evident from Fig. 1As can be seen, the button arrangement 50 is arranged on an upper side of the handpiece 2. This allows a user to hold the handpiece, for example, in such a way that the buttons of the button arrangement 5 are actuated with the thumb and the handpiece can be held securely with the remaining fingers in the hand.

[0050] In particular, a significantly improved haptic feedback is possible through the key arrangement 5. As can be seen in particular from the Figs. 5 and 6As can be seen, the rigid key plate 50 has a first raised area 51a on the first key 51 at a distal end and a second raised area 52a on the second key 52 at a proximal end of the rigid key plate 50. Starting from the first raised area 51a, the key plate tapers towards the third key 53. Also starting from the second raised area 52a, the key plate tapers towards the third key 53. The third key 53 also has a button-shaped third raised area 53a in the middle.

[0051] Thus, each key has different geometric dimensions, which can be felt simply by running a thumb over the keys. This enables intuitive operation of the key arrangement 5 without the user having to look at the key arrangement. This allows operations in which the surgeon usually monitors the position of the medical instrument inside the body on a screen to be carried out safely. Since the key plate 50 is rigid, this results in particularly good feedback for the user. In particular, by using the rigid key plate 50, it can always be reliably determined whether a key is pressed or not. This is a particularly significant advantage over other possible designs of keys with soft areas.

[0052] How to continue Fig. 5As can be seen, the first, second, and third raised areas 51a, 52a, 53a are equidistant from the central axis XX in the unactuated state (distance 14). This allows the height differences of the first, second, and third keys 51, 52, 53 to be easily sensed by touch.

[0053] The return of the rigid key plate 50 to the Fig. 5 The initial position shown is then achieved by resetting the reset elements 6, 7. Since the first and second reset elements 6, 7 are snap-action discs, an acoustic signal can also be integrated into the snap-action discs both when a button is pressed and when it is reset. This makes the operation of the medical instrument even more convenient and safe.

[0054] Thus, the button assembly 5 with three buttons 51, 52, 53 and two pushbutton contacts 55, 56 can provide three different operating modes of the medical instrument 1. For example, the first button can cause the inner cutting tube to rotate anticlockwise, the second button can cause the inner cutting tube to rotate clockwise, and the third button can enable an oscillating back-and-forth movement of the inner cutting tube.

[0055] Furthermore, the handpiece 2 comprises a suction regulator 54, which, as in Fig. 1 shown, arranged in series after the button arrangement 5. This allows a user of the medical instrument to typically operate the buttons of the button arrangement 5 and the suction control 54 for regulating the suction strength of the medical instrument with one hand or one finger.

[0056] Thus, a medical instrument 1 can be provided which has a connecting arrangement 4 that enables a very simple connection between the blade holder 3 and the handpiece 2, as well as a very simple detachment and attachment of the blade holder 3 from / to the handpiece 2. The push-button areas 42 of the connecting arrangement 4 protruding beyond the housing of the handpiece 2 also enable a simple visual actuation for detaching the blade holder 3 from the handpiece 4.

[0057] Furthermore, by providing two arms 40, which are arranged opposite one another on the handpiece 2, an unintentional detachment of the cutting edge holder 3 from the handpiece 2 can be prevented. This is particularly important when using the medical instrument 1, since a user usually holds the handpiece in the area of ​​the button arrangement 4 and thus close to the connection arrangement 4 between the handpiece 2 and the cutting edge holder 3. This does not completely rule out the possibility that the user inadvertently presses the pressing area 42 with a finger. However, by providing two opposing pressing areas 42 on the handpiece 2, even in the unintentional event that the user accidentally presses a pressing area 42, the cutting edge holder 3 is still securely fixed to the handpiece 2.This prevents accidental detachment of the cutting holder 3 from the handpiece 2 during an operation when the cutting holder 3 is located within a part of a patient's body.

[0058] Connecting the cutting edge holder 3 to the handpiece 4 can be achieved by simply sliding the cutting edge holder 3 axially onto the handpiece 4, since the two U-shaped recesses 45 in the handpiece 2, with their walls, allow the connecting assembly 4 to be guided at the pressing areas 42. Furthermore, the ring 46 with the arms 40 formed integrally thereon can also be detached from the cutting edge holder 3, thus allowing the cutting edge holder 3 and the connecting assembly 4 to be cleaned separately.

[0059] The button arrangement 5 according to the invention with a rigid button plate 50, three buttons, and exactly only two button contacts further improves the handling of the medical instrument in a surprising way. In addition to a structural simplification of the button arrangement, reliable actuation of the three buttons 51, 52, 53 and the suction control 54 is also possible. In particular, fewer plastic parts are required with the button arrangement 5 according to the invention, since all components of the button arrangement 5 can be made of a metal material. This is particularly advantageous when cleaning with liquids, since plastic parts dry only very slowly or with additional effort. This is not the case when metal parts are used. Particularly in conjunction with the connection arrangement 4, a significantly improved medical instrument can thus be provided, which has significantly simplified handling and better haptic properties during operation. List of reference symbols

[0060] 1Medical instrument 2Handpiece 3Cutting edge holder 4Connection arrangement 5Button arrangement 6Control board 7First reset element / first snap-action disc 8Second reset element / second snap-action disc 11First housing for the first touch contact 12Second housing for the second touch contact 13Holding plate for the first and second housing 14Gap 20Handpiece body 21Suction channel 22Cavity in the handpiece body 30Outer hollow tube 31Inner cutting edge tube 32Cutting edges 33Exit opening 40Arms 41Locking element 41aRamp 42Pressing area 43Elastic area 44Receptacle 44aUndercut 45U-shaped recess 46Ring 47Clip connection 50Button plate 51First button 51aFirst raised area 52Second button 52aSecond raised area 53Third Button 53athird raised area / button-like area 54extraction control 55first touch contact 56second touch contact 57cover 58lateral projection 59lateral recess in the cover Aactuation BWooling movement X-XAxial direction Y-YTiling axis of theKey layout

Claims

1. A medical instrument for arthroscopic procedures, comprising: - a handpiece (2), - a blade holder (3) with an outer hollow tube (30) and an inner hollow blade tube (31) with blades (32) at a distal end of the inner tube, and - a button arrangement (5) to operate the medical instrument, wherein the button arrangement (5) is arranged at the handpiece (2) close to a distal end of the handpiece (2), - wherein the button arrangement (5) comprises a first button (51), a second button (52) and a third button (53) as well as a first button contact (55) and a second button contact (56), wherein the first button (51) is configured to operate the first button contact (55), the second button (52) is configured to operate the second button contact (56), characterized in that the third button (53) is configured to operate the first and second button contacts (55, 56) simultaneously, - wherein the buttons (51, 52, 53) are arranged at a common, rigid button plate (50), - the rigid button plate (50) is arranged loosely at the button arrangement (5), and rests loosely on the first and second button contacts (55, 56), and is held at a first and second axial side at a cover (57) of the button arrangement (5).

2. The instrument according to claim 1, - wherein the three buttons (51, 52, 53) of the button arrangement (5) are arranged in series in axial direction (X-X), such that the third button is arranged between the first and second buttons, and / or - wherein the button arrangement (5) is arranged at an upper side of the handpiece (2).

3. The instrument according to any of the preceding claims, wherein the rigid button plate (50) is made of a metal material, in particular stainless steel.

4. The medical instrument according to any of the preceding claims, wherein the rigid button plate (50) comprises a first raised portion (51a) at the first button (51) at a distal end, a second raised portion (52a) at the second button (52) at a proximal end of the button plate, and a third raised portion (53a) at the third button (53) in the middle between the first and second buttons.

5. The medical instrument according to claim 4, wherein a distance (14) of the first raised portion (51a), the second raised portion (52a) and the third raised portion (53a) from a center axis (X-X) of the medical instrument is the same.

6. The medical instrument according to claim 4 or 5, wherein the first button (51) tapers towards the third button (53) and wherein the second button (52) tapers towards the third button (53).

7. The medical instrument according to any of the preceding claims, wherein the button arrangement (5) further comprises a control board (6), which is integrated into the button arrangement (5).

8. The medical instrument according to claim 7, further comprising a first resetting element (7) and a second resetting element (8), wherein the first resetting element (7) is arranged between the control board (6) and the first key contact (55) and the second resetting element (8) is arranged between the control board (6) and the second key contact (56).

9. The medical instrument according to claim 8, wherein the first and second resetting elements are each snap discs, which emit an acoustic signal when deformed.

10. The medical instrument according to any of the preceding claims, wherein the third button (53) is a particularly cylindrical protrusion on the rigid button plate (50) and / or wherein the rigid button plate (50) comprises a symmetrical narrowing in the portion of the third button (53).