Patent Application
20050096667
1. Field of the Invention
The present invention relates generally to devices and methods for the treatment of female urinary incontinence, and more particularly, to a guide to be used in conjunction with such devices and methods.
2. Background Discussion
Women account for more than 11 million of incontinence cases. Moreover, a majority of women with incontinence suffer from stress urinary incontinence (SUI). Women with SUI involuntarily lose urine during normal daily activities and movements, such as laughing, coughing, sneezing and regular exercise.
SUI may be caused by a functional defect of the tissue or ligaments connecting the vaginal wall with the pelvic muscles and pubic bone. Common causes include repetitive straining of the pelvic muscles, childbirth, loss of pelvic muscle tone, and estrogen loss. Such a defect results in an improperly functioning urethra. Unlike other types of incontinence, SUI is not a problem of the bladder.
Normally, the urethra, when properly supported by strong pelvic floor muscles and healthy connective tissue, maintains a tight seal to prevent involuntary loss of urine. When a woman suffers from the most common form of SUI, however, weakened muscle and pelvic tissues are unable to adequately support the urethra in its correct position. As a result, during normal movements when pressure is exerted on the bladder from the diaphragm, the urethra cannot retain its seal, permitting urine to escape. Because SUI is both embarrassing and unpredictable, many women with SUI avoid an active lifestyle and shy away from social situations.
One device and method for treating female urinary stress incontinence is described in detail in U.S. Pat. No. 5,899,909, which is incorporated herein by reference in its entirety. This patent discloses a surgical instrument comprising a shank having a handle at one end and connecting means at the other end to receive, one at a time, two curved needle-like elements which are connected at one end to one end of a mesh intended to be implanted into the body. In practice, the mesh is passed into the body via the vagina first at one end and then at the other end, at one side and the other, respectively, of the urethra to form a loop around the urethra, located between the urethra and vaginal wall. The mesh is extended over the pubis and through the abdominal wall and is tightened. The mesh ends are cut at the abdominal wall, and the mesh is left implanted in the body. This trans-vaginal procedure is exemplified by the TVT product sold by the Gynecare franchise of Ethicon Inc., a Johnson & Johnson Company, of Somerville, N.J., USA. In this procedure two 5 mm needles pass a PROLENE mesh trans-vaginally and through the abdomen to create a tension-free support around the mid urethra.
Sub-urethral slings have also been place by a different approach, wherein a needle is passed first though the abdominal wall, along the same path as described above, and eventually exiting through the vaginal incision. The tape is then coupled to the needle in some manner, and pulled back through the body from the vaginal incision and out through the abdominal incision. The chosen approach, vaginal or abdominal, will often depend on the preferences of the surgeon.
Yet another approach for implanting a sub-urethral sling has also been recently developed, wherein the implanted sling extends from beneath the urethra, and out through the obturator hole on either side. This “transobturator” procedure may involve inserting an appropriately configured needle from a vaginal incision and subsequently out through the obturator hole, or vice versa. The former technique (an “inside-out” approach) is described in further detail below. With these techniques, it has been found to be desirable to provide some sort of guide element to facilitate the path of the needle and to ensure that the needle does not nick or otherwise injure organs or nerves that are in the vicinity of the passageway of the needle. To this end, known guide elements have consisted simply of a small stainless steel tube, a portion of which has been removed to leave a straight, but C-shaped element. Such guide elements have proven less than optimal, however, as they are difficult to maintain in place without slipping, and don't provide protection against over-insertion which can lead to damage to surrounding tissues and organs. The present invention provides an improved guide device that can be used in conjunction with a transobturator approach for placing a sub-urethral sling.
These and other features and advantages of the present invention will become apparent from the following more detailed description, when taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
a, 7b and 8 illustrates steps that may be used in when using the guide element of the present invention to implant a sling; and
a-9c illustrate steps in a method for manufacturing a guide according to the present invention.
Before explaining the present invention in detail, it should be noted that the invention is not limited in its application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. The illustrative embodiments of the invention may be implemented or incorporated in other embodiments, variations and modifications, and may be practiced or carried out in various ways.
Referring now to
According to one embodiment, the extension portions each are further comprised of a stationary portion 112 that is fixed relative to the stem portion and a movable portion 114 that is movable relative to the stem portion. In the illustrated embodiment, the stationary portions are fixedly secured to the stem portion and the movable portions are movably secured to the stationary portions at one or more hinges 116 (see
In a preferred embodiment, the overall length L of the device is approximately 90 mm, but any length from approximately 80-120 mm or greater would be suitable. The overall length l of the extension portions is preferably 30 mm, but could be approximately 20-50 mm. The entire device is preferably made of stamped ¼ hard stainless steel having a thickness of approximately 0.5 mm (with approximately 0.25-1.0 m being a suitable range). The proper dimensions of the device will be further appreciated following the discussion below of the medical procedure with which it may be used.
As indicated above, the guide of the present invention may be used in conjunction with a surgical device and method to place a sub-urethral sling via a pathway that extends through the obturator foramen. In a preferred embodiment, the guide is used in conjunction with a surgical instrument 600 such as that shown in
To perform the procedure, the patient is first placed in the dorsal lithotomy position with the hips hyperflexed over the abdomen, and the bladder emptied. Next, the exit points 702 (
Next, the guide element 100 is inserted as shown in
The extension portions provide the added safety of having a “stop” to prevent the guide from accidentally being pushed too far into the body. To fully understand the benefits of the present invention, it is important to recognize that the obturator nerve and vessels are approximately 8.5-9.5 cm away from the entry point of the guide. This nerve and vessels are critical to avoid, as injury thereto could possibly cause paralysis. Thus, for most patients, to ensure safety of the guide element its length (the length that can be inserted) need not exceed approximately 6 cm. However, as indicated above, some patients either have larger pelvic frames, or are obese, rendering a guide length of 6 cm sub-optimal at best. Therefore, using known guides consisting simply of a straight transected cylinder (7 cm+3 cm) suitable to be inserted a full 10 or more cm, a surgeon would either have to always have available multiple guides having different lengths (i.e., one having an insertable length of approximately 6 cm and a second one having an insertable length of approximately 7 cm to accommodate patients with larger pelvic frames or obese patients), or rely on skill in using a single 7 cm round guide which could be inadvertently inserted to an unsafe depth of 7 to 10 cm for all patients. The latter is obviously dangerous and subject to human error, particularly with surgeons that are not highly experienced with the procedure. The former leads to added expense and waste. The guide of the present invention overcomes these problems by providing extensions to protect against over-insertion, (which the earlier invention did not prevent), with the extension having bendable portions for varying the insertable length of the stem to enable safe use in any patient.
Referring once again to the procedure, once the guide element is fully inserted on one side as described above, the surgical passer 602 with associated tube element 606 for that side of the body is then inserted. The assembly is positioned within the C-shaped stem portion and passed through the dissected tract following the channel of the stem portion of the guide element from the vaginal incision and through the obturator membrane. Once the tip of the assembly traverses the obturator membrane, the guide element is removed. The assembly is rotated the remainder of the way through until the tip emerges from the skin at the exit point. The end of the tube element is then grasped, and the surgical passer reverse rotated to bring it back through the dissected tract and out through the vaginal incision. Subsequently, the tube element is pulled through the skin incision until the tape 610 exits the skin incision. The process is then repeated on the patient's other side and the tape adjusted, leaving the tape to form the sub-urethral sling beneath the mid-portion of the urethra as shown in
Thus, with the aid of the guide device of the present invention, the procedure described above can be performed more safely and efficiently. The guide element ensures that the surgical assembly remains clear of any organs and nerves, while its configuration ensures its own safety by utilizing extensions to prevent over-insertion. Further, the above-described guide element is versatile enough to be used with any patient.
The above-described guide is preferably made using a unique stamping technology developed specifically for this application. Manufacturing processes that utilize stamping are well known. In general, a dye having the shape of the desired product “stamps” a sheet of metal to cut or punch the desired shape out of the metal. Stamping stainless steel produces sharp burrs around the edges that must be removed, particularly when the end product is a surgical device such as the present guide element. Stamping annealed stainless steel is even more difficult, as the softer the grade the more difficult burrs are to control given the gummy nature of the annealed stainless steel. The guide of the present invention requires a somewhat softer grade of stainless steel to allow the movable portions of the extensions to be bent (sometimes repeatedly) without breaking off.
Known tumbling, bead blasting, or chemical treatments are commonly used to remove burrs. Such treatments, however, tend to distort other product features. It is particularly important to avoid such distortion in the areas of the hinges. Hand removal techniques are labor intensive and expensive. Thus, known manufacturing techniques fail to offer a reliable and efficient way to use stamping technology to manufacture the above-described guides. Accordingly, a new stamping technique was developed that enables production of nearly burr-free stainless steel guides.
This new technique involves first using traditional stamping techniques and dyes to produce an initial specimen from which the burrs must be removed. A first dye 900 (
It will be apparent from the foregoing that, while particular forms of the invention have been illustrated and described, various modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims.
