BACKGROUND OF THE INVENTION Field of the Invention This invention relates to a clip and laparoscopic clip applicator for tubal ligation, and a method of performing the procedure. In particular, the invention relates to a small profile clip to be inserted through a small incision in the abdominal cavity of a patient in order to occlude the fallopian tubes, and to a method of performing the procedure using the device.

Tubal ligation is a safe, effective, and common means of contraception for women. The operation is now usually performed endoscopically using a small rigid laparoscope which is a viewing device containing a light source and a camera. A ligation clip and applicator or cautery device designed to occlude the patient's fallopian tubes is used. Laparoscopic instruments are designed to be inserted into the operative field through small incisions in the wall of the abdomen. The operation may also be performed without the aid of an endoscope by making a larger incision in a procedure commonly referred to as

minilaparotomy. In both procedures, the patient's fallopian tubes are closed using clips which are clamped in place using an applicator.

The prevalence of minimally invasive surgery has found applications in many realms of surgical practice. In the case of tubal ligation, laparoscopic sterilization has increased and minilaparotomy has decreased.

Laparoscopic sterilization results in a shorter less painful procedure and decreased use of health care resources. However, some pain and nausea still accompany the procedure. Recent studies have suggested that performing the procedure under local anesthesia has medical benefits including avoiding the costs and risks associated with a general anaesthetic. It also leads to a quicker recovery time and less time spent in the hospital.

Importantly, known clips and applicators are not designed specifically to be used with local anaesthetic due to their larger size.

Description of the Prior Art Examples of prior art include Hulka et al. (US Patent No. 3,882,854) and Casey et aL (US Patent No. 4,489,725).

Hulka et al. (US Patent No. 3,882,854) discloses a surgicai clip and applicator.

The clip is hinged around a stainless steel pin and is held open by a U-shaped spring. When the target fallopian tube is positioned between the jaws of the clip, the same spring is pushed over the top and bottom jaws of the clip by the applicator to secure the clamp in the closed position. The clip applicator is a laparoscopic instrument adapted to receive the clip.

Casey et al. (US Patent No. 4,489,725) discloses a surgical clip with two jaws hinged by lugs extending from the upper jaw mating with corresponding apertures in the lower jaw. The clip is closed by pressure from the applicator which deforms the upper jaw causing it to lengthen and abut against a latching portion of the lower jaw.

In the last several years, manufacturers have been able to miniaturize endoscopic lenses for insertion into the abdomen through an incision no larger than 2-4 mm in size. The prior art clips are too large to fit through such an incision. Accordingly, there is a need for smaller clips and applicators specifically designed for local anesthesia to realize the benefits of this type of procedure.

In addition, there is a small but significant failure rate for the prior art clips. The most common reason for the failures is misapplication. Accordingly, there is also a need for a method and an applicator which can reduce the potential for operator error.

SUMMARY OF THE INVENTION It is an object of the invention to provide an improved clip and applicator and a method of performing a tubal ligation procedure using the clip and applicator.

The improved clip and applicator according to the invention can be cost- effectively manufactured in a size small enough to fit through an incision 5 mm or smaller, allowing it to take advantage of the new miniature endoscopic lenses and making it particularly suitable for outpatient procedures performed under local anesthesia. This allows the patient to experience the benefits of a tubal ligation performed under local anesthesia, as well as reducing the use of costly hospital resources.

Furthermore, the device and method according to the invention provides an improved locking mechanism for the clip to reduce the potential for operator error and reduce the risk of incomplete fallopian tube occlusion.

The present invention relates to a clip and applicator for clamping a fallopian tube. The clip and applicator have complementary docking means for removably attaching one to the other.

The clip, which has a forward end and a rear end, comprises an upper jaw and a lower jaw body. The upper jaw and the lower jaw body each have a forward end and a rear end. The jaws are pivotally attached by means of a hinge and are adapted to pivot between a first open position where the jaws are apart, a second substantially closed position to minimize the profile or cross section of the clip for insertion through a small incision, and a third locked position where the jaws are pressed together to close the fallopian tube. Biasing means cooperate with the hinge to bias the jaws to the open position, specifically by means of upwardly locating and biasing the upper jaw with reference to the lower jaw body. Complementary locking means at the forward ends of the upper jaw and lower jaw body operate to lock the clip in the third closed and locked position.

The applicator comprises an elongate body over which a sleeve axially slides. The sleeve covers a rear section of the lower jaw when the clip is in the open position. The sleeve is adapted to push the jaws into the substantially closed position for insertion of the clip through the incision. The sleeve is also configured to push the jaws into the closed positions and lock the jaws in the

closed position by engaging the locking means thereby occluding the fallopian tube. Preferably, two slots are defined within the front end of the sleeve to accommodate the fallopian tube as the sleeve operates to close and lock the clip.

The invention also provides a method of closing a fallopian tube comprising the steps of: (a) attaching the applicator to a clip; (b) positioning the jaws of the clip in the substantially closed position (c) inserting the clip in the substantially closed position into the abdominal cavity through an incision; (d) releasing the jaws of the clip in the open position when the clip is inside the abdominal cavity; (e) positioning the clip such that the fallopian tube is located between the jaws of the clip; (f) locking the jaws of the clip to clamp the fallopian tube; (g) releasing the locked clip from the applicator; and (h) withdrawing the applicator.

Further features of the invention will be described or will become apparent in the course of the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be more clearly understood, a preferred embodiment thereof will now be described in detail by way of example, with reference to the accompanying drawings, in which: Figure 1 A is an isometric view of the clip.

Figure 1 B is an isometric view of the clip from a direction opposite to Figure 1A.

Figure 1C is an isometric view of the clip showing the front end of the clip in cross section.

Figure 2 is a cross sectional view of the applicator and clip.

Figure 3 is another cross section view of the applicator and clip showing the clip in a closed position.

Figure 4 is another cross section view of the applicator and clip showing the clip in a locked position.

Figure 5 is a view partly in section showing the applicator ready to be attached to the clip.

Figure 6 is a view partly in section showing the clip inserted into the applicator and being rotated.

Figure 7 is a view partly in section showing the clip secured within the applicator.

Figure 8 is an isometric view of the clip and applicator at the commencement of the closing sequence.

Figure 9 is an isometric view of the clip with the faceplate removed and the applicator showing the clip in the substantially closed position.

Figure 10 is an isometric view of the clip with the faceplate removed and the applicator showing the clip in the closed and locked position.

Figure 11 is a view partly in section of the underside of the concentric sleeve showing the key.

PREFERRED EMBODIMENT To better describe the invention, the terms up, down, front and rear will be used with reference to the clip. These directions are used as guides with reference to the orientation of the clip as shown in Figure 1 C.

Referring to Figures 1A and 1B, the clip 20 is comprised of an upper jaw 1 and a lower jaw body 3. The upper jaw 1 attaches to the lower jaw body 3 by means of a hinge 2. A suitable biasing means is provided to cooperate with

the hinge to upwardly bias the upper jaw 1 such that the clip 20 always tends to and remains in an open position. In the open position the clip 20 has a jaw like profile.

The hinge 2 is comprised of a pin member 4 which fits through corresponding apertures at the rear end of the upper jaw 1 and lower jaw body 3 respectively. Preferably, the pin 4 is made of titanium. The pin is orientated transversely and fixedly secured within the corresponding apertures of the lower jaw body by means of crimping the pin. The upper jaw, which is pivotally secured to the lower jaw body by the pin, is able open and close with reference to the lower jaw body 3. The ends of the pin are flush with the lower jaw body of the clip such that the clip may be safely inserted into and guided through the abdominal cavity.

The biasing means used to upwardly bias the upper jaw (not shown in figures) may be selected from at least two options. A resilient spring element located inside of the intersection of the upper jaw 1 and lower jaw body 3 may be used. The resilient spring element may comprise, for example, an integrally formed resilient arm extending diagonally upwards from the top surface of the lower jaw body abutting the bottom surface of the upper jaw. Alternatively, the means for upwardly biasing the upper jaw may comprise

some other resilient material located inside the intersection of the upper jaw 1 and lower jaw body 3, as for example, silicon.

To close the upper jaw 1, a downward force must be applied which is greater than the upward force exerted by the upward biasing means. The biasing means tends to force the upper jaw into the open position when the downward force is removed. Substantial closure of the clip to minimize its profile is necessary for insertion of the clip into the abdominal cavity through a small incision. After insertion, the clip must be able to open inside the abdominal cavity. The operation of the clip is described in greater detail later in the specification.

The outer surface of the lower jaw body 3 is generally smooth and rounded. The top surface of the upper jaw 1, which is preferably made of titanium, is flat. Each of the upper jaw 1 and lower jaw body 3 have interior opposing clamping surfaces 16A and 16B respectively which are generally flat and approximately 4 mm by 10 mm in dimension. During operation of the clip it is the interior clamping surfaces which occlude the fallopian tube.

Referring now to Figures 1A and 1C, the clip 20 has complementary locking means formed integrally adjacent its open ends which function to close and lock the upper jaw 1 with reference to the lower jaw body 3 in a manner

described hereinafter. As well, the clip has docking means 12 at its rear for engagement with and removable attachment to an applicator used to manipulate and install the clip as hereinafter described.

The complementary locking means consist firstly of a downwardly extending locking element 4 formed integrally and located at the front end of upper jaw 1. Secondly, the locking means consist of a receiving member 6 forming a cavity located at the front end of the lower jaw body 3 and formed integrally therewith which receives the locking element to retain it within thereby locking the upper jaw with reference to the lower jaw body. Figure 1C, which is a cross sectional view of the front end of the clip, shows the locking element 4 within the receiving member 6.

Referring to Figure 1A and in particular to Figure 1C, the locking element 4 is located at the extreme forward end of the upper jaw 1 and extends downwardly at substantially 90 degrees with reference to the upper jaw. The locking element terminates at a sharp point 17 and is further comprised of two outward protrusions18 located above the sharp point, one on each side thereof. The sharp point aids in the closure and subsequent locking of the clip by piercing a membrane attached to the fallopian tube.

Each protrusion 18 has an engagement surface and a locking surface. The engagement surface of each protrusion curves gently at its base and the outside edge is tapered inwardly. The inward tapering of the protrusions facilitates the insertion of the locking element 4 into the receiving member 6 and is described in greater detail later in the specification. The locking surface of each protrusion 18 is located at the top edge thereof and is outwardly perpendicular with reference to the body portion of the locking element 4. The locking surfaces abut the receiving member 6 to prevent the egress of the locking element 4 from the receiving member when the clip is in the closed and locked position, which is hereinafter described.

Referring still to Figures 1A and 1 C, the receiving member 6 is comprised of a faceplate 19 (removed in Figure 1C) located at the extreme front end of the lower jaw body and two sets of bars, an upper set of locking bars 22 and a lower set of supporting bars 23, which connect the faceplate to the lower jaw body 3. Each set of bars function to provide support and rigidity to the front end of the clip, and in particular to the receiving member. The locking bars 22 perform an additional function. Specifically, the upper set of locking bars cooperate and engage with the protrusions 18 of the locking element 4 to lock the clip in the closed and locked position. Each locking bar has an engagement surface and a locking surface. The engagement surface of each

locking bar, located on the inside surface thereof, is tapered inwardly at an angle corresponding to the outer tapered edges of the protrusions.

During ligation of the fallopian tube, the locking element 4 is forced into contact with the receiving member 6. More specifically, the engagement surface of each protrusion 18 comes into contact with the engagement surface of a corresponding resilient locking bar 22. The maximum width of the locking element, to be taken as the distance between the outer most edge of each protrusion, is greater than the width of the space separating the upper locking bars. Therefore, as a greater downward force is applied to the upper jaw 1, each protrusion 18 simultaneously exerts a greater outward force on its corresponding locking bar 22. The locking bars are flexed outwardly and spread apart in response to the outward force. The flexing of each locking bar is aided by the curved base and tapered outside edge of each protrusion, permitting the protrusions to slide downwardly over the locking bars. Once each protrusion has slid completely over and past its corresponding locking bar, the outward force is no longer exerted. Each resilient locking bar then automatically returns to its original unflexed configuration. The flat locking surface of the protrusions prevent the egress of the locking element as each protrusion catches and abuts against the locking surface of the locking bar it engages. This operation describes the means by which the upper jaw is locked to and secured to the lower jaw body of the clip.

Referring to Figure 1 B, the docking means consist of a cam like docking tab 12 attached to the end of the clip by means of stem 14.

Referring to Figures 1 B and 2, the docking means further include anti-rotation means located on the underside of the lower jaw body 3 of the clip which engage complementary means on the applicator. The anti-rotation means on the clip comprises a keyway 13 which is open at the rear as shown. The keyway 13 extends longitudinally along the underside of the lower jaw body ending with a stop 25 short of front end of the lower jaw body as better shown in Figure 4. The function of the keyway will be later described.

The applicator is now described. The purpose of the applicator is to hold and permit the clip to be manipulated by the surgeon during the tubal ligation procedure.

Referring to Figures 2,3 and 4, the operation of the applicator is described with respect to the clip. The applicator comprises a cylindrical core body 40 and a telescoping concentric sleeve 10 external to the core body 40. The forward end of core body 40 has receiving means for the docking tab 12 and the telescoping sleeve 10 which when operated moves forwardly to close and lock the clip around a fallopian tube.

Referring now to Figures 5,6 and 7, the applicator body 40 is hollow at its front end defining a cavity. An end plate 41 is provided having an aperture 11 which communicates with the cavity. The shape of the aperture corresponds to the shape of the docking tab 12. Thus the clip may be attached to and secured within the applicator by means of insertion of the docking tab into the aperture and rotation of the applicator body and end plate attached thereto with reference to the clip an angular distance with sufficient to wedge and secure the docking tab behind the end plate in the cavity.

Referring to Figures 8,9 and 10, the telescoping concentric sleeve 10 has jaw like cut out side openings 15 on each side corresponding in length to the length of the clamping surfaces of the clip when attached to the applicator as described. Referring to Figure 11, the telescoping concentric sleeve 10 also has a longitudinal key 50 located on the interior of the bottom sleeve which aligns with and engages keyway 13 of the clip (shown in Figures 1 B and 2) to prevent the rotation of the clip within and with reference to the applicator.

The telescoping concentric sleeve accordingly can be moved forwardly and rearwardly relative to the forward end of the core body as described hereinafter.

The tubal ligation method using the clip and applicator is now described.

Referring to Figures 5,6 and 7, the clip 20 is attached to and retained within the cylindrical core body 40 of the applicator by insertion of the docking tab 12 into the aperture 11 on the cylindrical core body 40 which is rotated an angular distance of 180 degrees with reference to the clip. This action wedges and secures the cam like docking tab behind the end plate 41 and prevents longitudinal separation of the clip from the applicator. Thus, the clip is functionally and removably attached to the applicator and is aligned so that the key 50 on the applicator is in a position to engage and slide into the keyway 13 of the clip.

Referring to Figures 2 and 8, the telescoping concentric sleeve 10 is moved forwardly over the clip. This step engages the key 50 within the keyway 13 located on the underside of the clip, and prevents any rotation of the clip with reference to the applicator body. At this stage the clip is in the open position and has a jaw like profile. The upper jaw 1 and lower jaw body 3, specifically the clamping surface of each, are substantially apart.

Referring now to Figure 3, the forward movement of the concentric sleeve now depresses downwardly the upper jaw 1 over the lower jaw body 3 of the clip. This motion forces the upper jaw towards the lower jaw body. When the locking element 4 comes into contact with the receiving member 6, the

surgeon receives a tactile sensation, as the telescoping concentric sleeve no longer slides easily over the clip. As described above, in order to lock the clip, a pre-determined downward force must be exerted to overcome the resistance provided by the locking bars 22. The tactile sensation of the engagement surface of each protrusion 18 engaging its corresponding locking bar indicates that the clip is in the substantially closed position for the purpose of insertion into the abdominal cavity. A tactile indication that the clip is in the substantially closed position also assists in ensuring that the surgeon does not accidentally lock the clip, which operation is hereinafter described. It is important to note that this closed orientation of the clip presents a minimum forward profile or cross section, which is one of the important objects of the invention.

Additionally, tactile feedback to the surgeon may be provided by means of an abutment 26 located on the top surface of the upper jaw 1. Contact of the front edge of the telescoping concentric sleeve 10 with the abutment 26 provides the surgeon with a tactile indication that the clip is in the substantially closed position. An abutment provides a redundancy or additional tactile indication that the clip is in the closed position to ensure that the surgeon does not accidentally lock the clip.

In the substantially closed position, as illustrated in Figure 3, the forward profile or cross section of the clip 20 is minimized permitting insertion of the clip and applicator which is attached thereto into the patient's abdominal cavity through a small incision. No attempt is made here to describe any particular surgical technique or procedure which a particular surgeon would use. Rather the physical features of the applicator and clip and its operation are sought to be described.

When the substantially closed clip has been inserted into the patient's abdominal cavity, the surgeon, with the aid of a laparoscopic device, retracts the telescoping concentric sleeve 10 which action permits the upper jaw 1 to return to its preferred biased open position described above and shown in Figures 2 and 8. The surgeon then positions the clip such that the targeted fallopian tube (not shown) is positioned between the inner clamping surfaces 16A and 16B.

After the operator has positioned the targeted fallopian tube (not shown) between the clamping surfaces 16A and 16B, the telescoping concentric sleeve 10 is again moved forwardly over the upper jaw 1 and lower jaw body 3 of the clip. Once again, the surgeon receives the tactile sensation of the locking element coming into contact with the receiving member, or sleeve 10 coming into contact with abutment 26, prior to locking the clip as described

hereinafter. The side openings 15 on the telescoping concentric sleeves 10 provide clearance for the fallopian tube.

Referring to Figures 3 and 4, and also 9 and 10, the surgeon now moves the telescoping concentric sleeve 10 forwardly, overcoming the resistance provided by the locking bars and until the key 50 abuts against stop 25 located on the underside of the lower jaw body 3 of the clip. Figure 9 shows the locking element within the receiving member, and specifically the locking bars being forced outwards in response to the downward force applied to the upper jaw. The leading edge of the telescoping concentric sleeve continues to advance in a forward direction out over and past the locking element. As a consequence, the locking element moves downwardly such that the protrusions pass completely through the locking bars and such that the locking surface of each protrusion engages the locking surface of its corresponding locking bar as described in detail earlier in the specification, and shown in Figures 4 and 10. This operation locks the upper jaw with reference to the lower jaw body of the clip. The clip is now in a closed and locked position and the fallopian tube is occluded.

The clip 20 may now be disengaged from the applicator by rotating the core body 40 through an angular distance of 180 degrees in the opposite direction such that the docking tab and aperture are once again in alignment, while

holding the clip secure within the concentric sleeve 10 by means of the keyway 13. This operation releases the docking means and permits the applicator to be directly withdrawn from the abdominal cavity leaving the clip attached to and occluding the fallopian tube.

From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.