HK1115073B - Applicator for inserting an implant - Google Patents

Description

Manipulator for inserting an implant

The invention relates to an applicator (applicator) for inserting an implant, in particular a rod-shaped implant containing an active substance, under the skin of a human or animal, comprising a housing, a cannula holder, an implant accommodated in the cannula and/or the cannula holder, a shield for the cannula and means for fixing the implant in the cannula and/or the cannula holder.

Such manipulators are well known in the art.

EP 0631794 relates to a device for introducing an implant, comprising an active substance container (designated by reference numeral 1) having an injection cannula 6 and a plunger 4. A plunger 4 is disposed within the plunger channel 3. The plunger channel 3 merges continuously into the cavity of the cannula 6. A holding device 5 for the implant 2 is arranged in the end of the plunger channel 3 on the cavity side. The clamping device comprises two bolts ("Bolzen 7, 8") which constitute obstacles of the implant ("Hindernis").

US 2001/031940 relates to a device for introducing an implant. The device is a syringe-like device having a plunger, an injection cannula and an active substance container located therebetween. The active substance container comprises two retaining elements for preventing accidental release of the implant. The retaining element is flexible and may be an O-ring.

US 5,484,403 relates to a hypodermic syringe for implanting objects in the bodies of birds, fish, animals and humans, which syringe comprises a barrel, a catheter connected to one end of the barrel and a plunger which is movable back and forth within the barrel. The user implants the article by: an article is placed into the cannula, the cannula is notched, and the plunger is then pushed, thereby moving the article from the cannula through the notch and into the body. The cannula is provided with means, in particular a crimping zone (indicated with 31), to firmly hold the implant object within the cannula from the moment of insertion of the object into the cannula until the moment of implantation.

US 5,395,319 relates to a needle (indicated by reference numeral 12) having a sharp point 14 at the tip and a needle holder 16 holding the needle at the rear end, and a spindle 24 movable within the needle and optionally a protective cover 18 enclosing the needle point and detachably connected to the needle holder, whereby an article 10, such as a long-term preparation, a label or the like, is inserted into the body of a living being. In order to ensure a positive fixing thereof in position in the needle, an article is arranged between the closure towards the needle tip and the constriction 20, for example towards the handling end. At the tip of the needle, at least a part of the area of the needle cavity may be closed by a paste-like material containing a medically active ingredient, which material continuously adheres to at least a part of the area of the article during insertion. This provides at least a precaution against inflammation. However, the closure may also be an adhesive material or a silicon plug, for example.

Many implants, especially those that slowly release the active substance over an extended period of time, are delicate. These delicate implants can be damaged by bolts, O-rings, crimped regions, and other closures within the cannula lumen.

It is an object of the present invention to provide an applicator which, on the one hand, secures an implant in a cannula and/or a cannula holder and, on the other hand, facilitates avoiding damage to the implant, especially during insertion thereof.

To this end, the invention provides a manipulator for inserting a rod-shaped implant containing an active substance under the skin of a human or animal body, comprising a housing, a cannula holder, a rod-shaped implant accommodated in the cannula and/or the cannula holder, a protective cover for the cannula and a first mechanism for securing the rod-shaped implant in the cannula and/or the cannula holder at least after the protective cover has been removed from the cannula, characterized in that the first mechanism detaches the rod-shaped implant containing the active substance during or after the cannula has been inserted and before the implant is expelled from the cannula. The first mechanism comprises a lever extending along at least part of the cannula, the lever being rotatable and/or slidable and/or bendable between a first position and a second position; wherein in a first position the implant is secured within the cannula and/or cannula holder and in a second position the implant is detached, the cannula and/or cannula holder comprising an opening enabling access to the implant and the lever comprising a protrusion aligned with the opening.

Preferably, the mechanism secures the implant within the cannula once the cover is removed, and disengages the implant prior to expulsion from the cannula.

Thus, as long as the cap is in place, i.e. typically throughout storage, substantially no force will be applied to the implant, and substantially no lateral force will also be applied to the implant upon expulsion from the cannula.

More preferably, the mechanism comprises a lever extending along at least a portion of the cannula, the lever being rotatable and/or slidable and/or bendable between a first position, in which the implant is fixed, preferably engaged by the lever itself within the cannula and/or the cannula holder, and a second position, in which the implant is disengaged.

If the cannula and/or the cannula holder comprises an opening enabling access to the implant and the lever comprises a protrusion aligned with the opening, the manipulator may be constructed in a relatively simple and efficient manner. Furthermore, if there is no implant in the cannula, the protrusion will prevent the cannula from being retracted.

In another preferred embodiment, the lever is biased towards the cannula and/or the cannula holder and (gently) pushes the implant towards the inner wall of the cannula or the cannula holder.

In another preferred embodiment, the lever locks the cannula or the cannula holder in its first position, preventing a movement in the longitudinal direction, and unlocks the cannula or the cannula holder in its second position.

The invention also relates to an applicator comprising a mechanism for locking a (detachable) cover to a housing if no implant is present in the cannula and the cannula holder. Thus, the cap is not detachable and thus hinders cannula insertion, or even prevents the implant from being inside the cannula.

Such an applicator preferably comprises a lever extending along at least part of the cannula, the lever being rotatable and/or slidable and/or bendable between a position in which the cover is locked (if no implant is present) and a position in which the cover is unlocked (if an implant is present).

It is noted that US 5,906,599 discloses a device for delivering a biological agent comprising a cannula for insertion into tissue, the cannula having a distal end with a notch formed therein. The flexible membrane extending across the cannula notch has a surface for supporting a quantity of biological agent. A displacement member is disposed within the cannula for displacing the bearing surface of the membrane laterally relative to the cannula to precisely deliver the biological agent to the tissue site or body cavity.

US 1,655,158 discloses an instrument for implanting radon tubules, which consists of three elements, an implanter 1, a trocar 2 and a plunger 3. The implanter comprises a tubular body portion 4 and a needle 5.

WO 2004/089458 discloses a device for inserting implantable articles under the skin of a patient comprising a handle for grasping the device and a base connected to the handle. The base includes a post, a sleeve, and a flexible actuator located on an angled track.

WO 01/68168 discloses a disposable device for inserting one or several implants, said device comprising: a tubular sleeve 10 provided with a tip 11, said sleeve also serving as a receptacle for the implant; a plunger 20; and a handle 30; the handle has a first end 31 facing the cannula 10 and a second end 32 facing away from the cannula.

US 5,827,297 discloses a device for transplanting small diameter hair grafts using a hand-held cutter having a body holding a tool, a rotating cylindrical tool, and a drive assembly capable of driving the tool in rotation relative to the body.

US 6,402,716 discloses a syringe assembly comprising a protective member containing an ejection elongated rod, a cover member for covering a needle having a thin rod formed in its closed end, the thin rod extending a predetermined distance towards the needle portion to hold the needle in place and to contain the injection material therein.

US 5,695,463 discloses an injection device for intramuscular or subcutaneous injection of solid or semi-solid medicaments. The device includes a body member having a needle attached thereto. The sheath is covered over the needle and is retracted into the body member when the device is pressed against the patient's skin.

US 5,279,554 discloses a device for implanting an article subcutaneously in an animal, such as implanting a hormone pellet or an electronic transponder, the device comprising: a hollow needle (1) having an operating rod (11) slidable therein; a cap (2) movable relative to the needle to enable at least the tip of the needle to be covered; and a locking mechanism in the form of a seat (10) movable into the socket (6) and from which it cannot return.

US 6,592,508 discloses an implantation device comprising an implantation needle having a bore extending longitudinally therethrough from a proximal end to a distal end, the needle bore being adapted to allow at least one seed-shaped tubule to pass therethrough.

The invention will be explained in more detail with reference to the drawings, in which two preferred embodiments of the invention are schematically shown.

Fig. 1 is a perspective view of a first embodiment of the applicator of the present invention.

Fig. 2 is a perspective view of the same operator as in fig. 1, but with its protective cover removed.

Fig. 3 and 4 are top and cross-sectional side views, respectively, of the preferred applicator of fig. 1, with the cannula in an extended position.

Fig. 5 is a cross-sectional side view of the preferred applicator of fig. 1, with the cannula in a retracted position.

Fig. 6 is an exploded view of the preferred applicator of fig. 1.

Figure 7 is a perspective view of the protective cover.

Fig. 8 shows a top view, a cross-sectional view and a rear view of a lever for the preferred operator of fig. 1.

Fig. 9 is a perspective view of a second embodiment of the applicator of the present invention.

Fig. 10 is a cross-sectional side view of the preferred applicator of fig. 9, with the cannula in an extended position.

Fig. 11 is an exploded view of the preferred applicator of fig. 9.

Figures 1 to 8 show a preferably disposable applicator for inserting an implant 2, in particular a rod-shaped implant containing an active substance, such as a contraceptive, under the skin of a human body. The operator 1 includes: a housing 3, which housing 3 is composed of two half-shells 4, 5; a metal sleeve 6 for receiving the implant 2 (fig. 2); a protective cover 7 (fig. 1 and 4), the cover 7 comprising a pin 7A extending into the tip of the cannula 6 so as to limit the free movement of the implant 2; and an actuator 8 for retracting the sleeve 6 into the housing 3. The cannula 6 is fixed to a cannula holder 9 which is slidably accommodated within the housing 3. For this purpose, the inner wall of each of the half-shells 4, 5 is provided with two parallel and longitudinal guides 10 (fig. 6), and the cannula holder 9 is provided with corresponding longitudinal grooves 11. The cannula holder 9 is connected to the actuator 8 by means of a flexible element 12, which flexible element 12 is in this example integral with the cannula holder 9 and the actuator 8. Depending on the configuration of the manipulator, it may be more advantageous to use rigid elements and/or separate actuators, flexible elements and needle holders, which are connected together when the manipulator is assembled.

In fig. 6 it can be seen that the cannula holder 9 comprises a collar 13 at its front (distal) end, at the transition to the cannula 6, and a recess 14 on its bottom surface near its rear (proximal) end. These features will serve to lock the cannula holder and thus the cannula in the extended and retracted positions, respectively, as described below.

The housing 3 comprises a handle 15 for gripping and handling the cannula 6 during insertion. The handle 15 extends above, i.e. along and spaced from, the cannula 6, preferably close to the distal end of the cannula 6, and facilitates insertion of the cannula 6 and/or accurate positioning of the implant 2. To further enhance the grip of the operator and the operating cannula, it is generally preferred that the thickness and bending stiffness of the handle is greater than the thickness and bending stiffness of the cannula, respectively.

At the top of the handle 15, a track 16 is provided for guiding the actuator 8. A guide (not shown) may be included, preferably just below the track 16, to hold and guide the flexible element 12.

The bracket 17 is inserted into the rear end of the housing 3 and snap-fitted thereto by means of two resilient fingers 18, 19, each provided with a projection 18A, 19A. The lower finger 19 also comprises a wedge-shaped protrusion 20 near its end. The bracket 17 further comprises a rod 21 which extends through a larger part of the housing 3 and into the cannula holder 9 and the cannula 6. In this example, the length of the rod 21 is adjusted to the length of the lumen of the cannula holder 9 and the cannula 6 and the length of the implant 2 such that when the cannula 6 is in the extended position, the implant 2 is completely contained within the cannula 6 and generally abuts the distal end of the rod 21. When the cannula 6 is in the retracted position, the implant 2 is fully expelled from the cannula 6, while the distal end of the rod 21 extends from the distal end of the cannula 6 (retracted).

The lever 22 has been pivotally connected to the front end of the handle 15. The lever 22 is gently biased towards the cannula 6 by means of a metal spring (not shown) extending between the lever 22 and the inner wall of the handle 15. In this preferred embodiment, the lever 22 interacts with the protective cover 7, the implant 2 and the cannula holder 9. To this end, the lever 22 includes (from left to right in fig. 8) a first projection 23 on its lower wall, a pair of lateral projections 24 on its upper edge, and a vertically extending slot 25 on its rear wall.

The protective cover 7 (fig. 7) comprises on its inner wall a pair of ridges 26 forcing a sliding engagement between the cover 7 and the casing 3, in cooperation with corresponding slots 27 on the outside of the casing halves 4, 5. The lid 7 also comprises a pair of keys 28 at its upper edge, each key 28 being interrupted by a recess 29.

Finally, the cannula 6 comprises an opening 30 (fig. 6) which enables the protrusion 23 to engage the implant 2 and thereby gently push the implant 2 against the inner wall of the cannula 6.

With the protective cover 7 in place, the lateral projection 24 of the lever 22 is supported by the key 28, while the first projection 23 is just clear of the implant 2.

If the protective cover 7 is removed, i.e. slid in the longitudinal direction and away from the housing 3, the key 28 will slide under the lateral projection 24. If no implant 2 is present in the cannula 6, the protrusion 23 on the lever 22 is free to enter the cannula 6 through the opening 30. I.e. the lever 22 will fall when the lateral protrusion 24 reaches the recess 29, thereby preventing the cover 7 from being moved further, preventing it from being removed and preventing the operator from being used further. If there is an implant 2, the lever 22 will be lowered only slightly, while the lateral projection 24 is still clear of the recess 29 and also causes the first projection 23 to rest on the implant 2 through the opening 30. Thus, on the one hand, the cover 7 will be able to be removed and, on the other hand, the implant 2 will be gently pushed against the inner wall of the cannula 6, i.e. the implant 2 is fixed within the cannula 6.

The medical professional can now grip the applicator 1 with one hand, for example with the thumb on one side of the handle 15 and the fingers on the other side, and insert the cannula 6 under the skin of the patient. During insertion, the handle 15 enables coordinated manipulation of the applicator 1 and cannula 6 and careful lifting of the skin to facilitate insertion of the implant 2 to the appropriate depth. The skin at the top of the cannula 6 lifts the lever 22 to such an extent that contact between the protrusion 23 and the implant 2 is eliminated, i.e. the implant 2 is disengaged without special action by the medical staff, and the slot 25 in the rear wall of the lever 22 is clear of the collar 13 on the front of the cannula holder 9, thereby unlocking the cannula holder 9. Subsequently, the actuator 8 is unlocked and the cannula 6 is pulled backwards, for example with the index finger of the hand holding the applicator 1. During this rearward movement, the implant 2 abuts the distal end of the rod 21 and maintains its longitudinal position. Only limited friction forces are generated between the implant 2 and the inner wall of the cannula 6, while substantially no lateral forces are exerted on the implant 2. When the needle holder 9 reaches the fully retracted position, the finger 19 (part of the bracket 17) will bend downwards and the projection 20 on this finger 19 will snap momentarily into the recess 14 on the lower surface of the needle holder 9, preferably with an audible click, indicating to the medical staff that the implant 2 has been inserted and that the applicator 1 can be removed and discarded. The projection 20 and the recess 14 likewise form a lock to prevent the operator 1 from being used again.

Figures 9 to 11 show a second embodiment of the manipulator of the invention. The main differences from the first embodiment will be discussed below. Those elements in the first embodiment which are at least substantially identical are denoted by the same reference numerals.

In the second embodiment, the housing 3 is composed of two side housings 4, 5 welded (ultrasonically) together and a single rear portion 3A, which rear portion 3A is snap-fitted to the side housings 4, 5. The handle 15 and the protective cover 7 are provided with reliefs (relief) on both sides, in this case in the form of projections 31, in order to enhance the grip and to achieve a guiding action when gripping these respective parts 15, 7. A similar protrusion 31 has been provided on the (upper) edge of the actuator 8.

Further, the cover 7 includes a stay (stay)32 on its inner bottom wall, preferably a V-shaped groove extending in the longitudinal direction of the operator 1 on its top surface. Once the protective cover 7 is placed on the housing 4, 5, the stay 32 slightly lifts the sleeve 6 and reproducibly defines the lateral position and height of the tip of the sleeve 6 with respect to the pin 7A, thus preventing contact between the needle tip and the inner wall of the cover 7.

The flexible element 12 interconnecting the actuator 8 and the cannula holder 9 comprises, preferably just below the actuator 8 and on either side of the flexible element 12, lateral protrusions 33. The inner walls of the housings 4, 5 in turn comprise two respective stops 34 which prevent the projection 33 from passing through and thus the actuator 8 from being inadvertently pulled backwards. The lateral projections 33 and the stops 34 also prevent the cannula holder 9 and the cannula 6 from being pushed towards the rear during insertion.

A guide 35 for holding and guiding the flexible element 12 is arranged just below the rail 16. The guide 35 is shaped to provide sufficient space under the actuator 8 to allow the element to bend down far enough and the lateral projection 33 to pass the stop 34 when the actuator 8 is pushed down. Thus, the cannula 6 can be retracted in one flow movement, i.e. upon application of pressure to the actuator 8, typically with an index finger, the actuator 8 flexes downwardly, away from the stop 34, and then moves rearwardly to the retracted position.

In contrast to the first embodiment, there is no collar (13) at the front (distal) end of the cannula holder 9. Instead, two resilient projections 36 are provided at the rear (proximal) end of the cannula holder 9. Two corresponding stops (not shown) are likewise included on the inner side walls of the housings 4, 5, which stops the rearward movement of the projection 33 and thereby defines the longitudinal position of the cannula holder 9 in the rearward direction. Preferably, the mechanism advances the cannula holder 9 to its most forward position, thereby preventing the implant 2 from protruding from the cannula 6. Upon actuation, the projection 33 will flex inwardly and past the stop.

As is evident from the above description, the preferred applicator of the present invention (automatically) secures the implant within the cannula upon removal of the protective cover and (again automatically) disengages the implant when insertion of the cannula under the skin of the patient has been substantially completed.

The applicator according to the invention is therefore particularly suitable for delicate implants, in particular implants which slowly release an active substance over a long period of time. A preferred example of such an implant is a single-rod contraceptive implant which prevents pregnancy over a long period of time, for example 3 years. This implant consists of a non-biodegradable rod of length 40mm and diameter 2 mm. After insertion, the rod slowly releases the progesterone hormone, i.e. the estrogen (etonogestrel).

The invention is not limited to the embodiments described above, which can be varied in a number of ways within the scope of the claims. For example, rather than pivotally mounting the lever to the housing, the lever may be formed in whole or in part from a flexible material that allows the lever to flex between its different positions.

Claims (13)

1. Applicator (1) for inserting a rod-shaped implant (2) containing an active substance under the skin of a human or animal, comprising a housing (3), a cannula (6), a cannula holder (9), a rod-shaped implant (2) accommodated in the cannula (6) and/or the cannula holder (9), a protective cover (7) for the cannula (6), and first means (22, 23) for fixing the rod-shaped implant (2) in the cannula (6) and/or the cannula holder (9) at least after the protective cover (7) has been detached from the cannula (6), characterized in that the first means (22, 23) detach the rod-shaped implant (2) containing the active substance during insertion of the cannula (6) or after insertion of the cannula (6) and before the implant (2) is expelled from the cannula (6), the first means (22, 23), 23) Comprises a lever (22) extending along at least part of the cannula (6), the lever (22) being rotatable and/or slidable and/or bendable between a first position and a second position; wherein in a first position the implant (2) is fixed into the cannula (6) and/or the cannula holder (9) and in a second position the implant (2) is detached, the cannula (6) and/or the cannula holder (9) comprises an opening (30) enabling access to the implant (2) and the lever (22) comprises a protrusion (23) aligned with the opening (30).

2. Applicator (1) according to claim 1, wherein the first mechanism (22, 23) secures the implant (2) within the cannula (6) once the protective cover (7) is removed.

3. Applicator (1) according to claim 1, wherein the lever (22) is biased towards the cannula (6) and/or the cannula holder (9) and pushes the implant (2) towards the inner wall of the cannula (6) or the cannula holder (9).

4. Applicator (1) according to claim 1, wherein the housing (3) comprises a handle (15) extending over at least part of the cannula (6), the lever (22) being rotatably connected to a distal end of the handle (15).

5. Operator (1) according to claim 1, wherein, when mounted, the protective cover forces the lever into its second position.

6. Operator (1) according to claim 1, wherein the lever (22) locks the cannula (6) or the cannula holder (9) in its first position and unlocks the cannula (6) or the cannula holder (9) in its second position.

7. Operator (1) according to claim 6, wherein the lever (22) comprises at least one protrusion or recess (25), the cannula (6) or the cannula holder (9) comprises at least one recess or protrusion (13) corresponding to the at least one protrusion or recess (25) of the lever (22), respectively, and wherein the at least one recess (25) of the lever (22) is interlocked with the protrusion (13) of the cannula (6) or the cannula holder (9) corresponding to the at least one recess (25) of the lever (22) in the first position of the lever (22).

8. Operator (1) according to claim 1, comprising a stem (21) mounted on or in the housing (3) and located at least partially inside the sleeve (6), and an actuator (8), the actuator (8) being adapted to slide the sleeve (6) and the stem (21) relative to each other.

9. Applicator (1) according to claim 1, characterized in that the second mechanism (24, 28, 29) locks the protective cover (7) to the housing (3) in case no implant (2) is present in the cannula (6) or the cannula holder (9).

10. Operator (1) according to claim 9, comprising a lever (22), which lever (22) extends along at least part of the cannula (6) and is rotatable and/or slidable and/or bendable between a position in which the protective cover (7) is locked and a position in which the protective cover (7) is unlocked.

11. Applicator (1) according to claim 10, wherein the cannula (6) and/or the cannula holder (9) comprises an opening (30) enabling access to a cavity of the cannula (6) and/or the cannula holder (9), and the lever (22) comprises a protrusion (23) aligned with the opening (30).

12. Applicator (1) according to claim 1, housed in a sterile package.

13. The applicator according to claim 1, wherein the implant is comprised of a non-biodegradable rod containing a proestrogen.