Patent Description:
A penile prosthesis (a device is a prosthesis prior to implant and a prosthetic after implantation) could be a malleable and non-inflatable device or an inflatable device. The malleable device has a flexible core that is bendable to various orientations, which for example allows the user to bend the penile implant to a desired erect shape or to a relaxed state. An inflatable penile prosthesis typically includes a pair of cylinders implantable in the penis, a reservoir implantable in the abdomen, and a pump implantable in the scrotum that is employed to move liquid from the reservoir into the cylinders. Pumping liquid from the reservoir to the cylinders inflates the penile implant to allow for penetrative intercourse.

Each of these penile prostheses has a portion that is implanted within the penis. The distal portion of the penile prosthesis is implanted within a dilated corpus cavernosum, and the proximal portion is implanted within a dilated crus penis. There is often a variation in the depth and width of the dilated crus penis, even within an individual patient. The surgeon desires to appropriately fit the proximal portion of the penile prosthesis within the crus and might desire to attach length-extenders to the implant to adjust for the depth of the crus penis. These length-adjusting accessories should be easy to attach yet resistant to detaching from the implant in the case of explant.

Exemplary length extenders are known from <CIT>, <CIT>, <CIT>.

Surgeons and users would benefit from devices that improve the fit of an implantable penile prosthesis within the penis.

The accompanying drawings are included to provide a further understanding of embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and together with the description teach principles of this disclosure. Other embodiments and the intended advantages of embodiments will be readily appreciated as they become better understood by reference to the following detailed description.

A rear tip extender for a penile prosthesis is disclosed. The rear tip extender includes multiple locks for connecting the rear tip extender over a proximal end of the penile prosthesis. The multiple locks advantageously secure the rear tip extender to the penile implant so that, in the event of a future explantation of the implant, the rear tip extender is removed along with the removal of the distal penile implant. At least one of the multiple locks on the rear tip extender mates smoothly with an exterior surface of the penile prosthesis to limit or prevent the formation of a gap or space between the rear tip extender and the penile prosthesis. The multiple locks allow the rear tip extender to maintain engagement with the prosthesis and limit gap formation between these two components even when bending forces are present during use, thus reducing or eliminating tissue ingrowth between the rear tip extender and the prosthesis over the life span of the implant, which is beneficial in case of a future explant procedure.

In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as "top," "bottom," "front," "back," "leading," "trailing," etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments can be positioned in different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized, and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense.

The features of the various exemplary embodiments described in this application may be combined with each other, unless specifically noted otherwise.

The term "proximal" as employed in this application means that part that is oriented closest to a center of the human body.

The term "distal" as employed in this application means that part that is situated farthest away from the center of the human body. A distal end is the furthest endmost location of a distal portion of a thing being described, whereas a proximal end is the nearest endmost location of a proximal portion of the thing being described. As relates to penile implants, the proximal portion of the penile implant is implanted in the crus penis and the distal portion of the penile implant is implanted in the pendulous (external portion) of the penis.

The length and width of the penile prosthesis that is implanted in the distal portion of the penis is selected by the surgeon after the surgeon measures the length and girth of each dissected corpus cavernosum. Common sizes for the penile prosthesis implanted in each corpus cavernosum are characterized as "standard" or "narrow. " The length of the prosthesis implanted in the crus penis may be adjusted by using one or more rear tip extenders that are attached to the proximal portion of the prosthesis.

Surgeons desire rear tip extenders that are easy to attach and resistant to detaching from the implant. Tissue will naturally grow around an implant. It is advantageous to have durable rear tip extenders that can withstand bending forces without forming a gap between the location where the rear tip extender engages the prosthesis. Reducing or avoiding the formation of the gap between the two components of the penile implant avoids eventual tissue accumulation in the gap, which could complicate a possible later explant procedure.

We describe a rear tip extender having multiple locks for coupling with a penile prosthesis. The multiple locks advantageously secure the rear tip extender to the penile implant, which in the event of a future explant, ensures the rear tip extender is removed along with the penile implant. The rear tip extender mates with the penile prosthesis in a way that prevents the formation of a gap or space between the rear tip extender and the penile implant, even if the rear tip extender experiences bending forces during use. The reduction or elimination of the gap spaces between the two components reduces or eliminates tissue ingrowth into the gap or space, which is also beneficial in the case of a future explant.

We describe a system of a rear tip extender attachable to a penile prosthesis including multiple locks that improve the resistance of the rear tip extender from removal from the penile prosthesis by double (a factor of <NUM> in pull-off force) over compared to the pull-off force specification for conventional rear tip extenders and penile implants. Embodiments of the system of the rear tip extender attachable to the penile prosthesis described below also reduce or eliminate separation of the rear tip extender away from the location where it is joined to the penile implant, as can sometimes occur in the presence of bending of the implant during use. The multiple locks connecting the rear tip extender to the penile prosthesis thus reduces or eliminates the formation of a gap between the components after implantation that can lead to undesirable tissue ingrowth between the components. Consequently, embodiments of the rear tip extender and penile implant system described below provide improved engagement between the rear tip extender, to reduce or eliminate tissue ingrowth between the components, and provide a system having improved explant capabilities.

One embodiment described in the application provides an implantable penile prosthesis system comprising a penile implant and a rear tip extender. The penile implant comprises a proximal portion implantable in a crus penis, with the proximal portion of the penile implant comprising: a groove formed around at least a portion of a circumference of the penile implant and having a groove diameter, a tapered section proximal the groove, with the tapered section having a continuous reduction in diameter from the groove toward a proximal-most end of the penile implant, and a neck groove formed in the tapered section between the proximal-most end of the penile implant and the groove. The groove in the proximal portion of the penile implant is referred to as an annular groove. The annular groove is a recessed area that may be suitably formed as a U-shaped groove or a C-shaped groove. Likewise, the neck groove is a recessed area and can be formed in a variety of shapes, such as in one example, a square-shaped groove with right angles. The rear tip extender forms a cavity sized to receive the proximal portion of the penile implant, with the cavity defined by an interior wall and provided with a plurality of locks comprising: a distal lock formed as an annular protrusion extending radially inward away from the interior wall of the cavity, where the annular protrusion is sized to engage with the annular groove of the penile implant, and a proximal lock formed as a wedge-shaped tooth extending radially inward away from the interior wall of the cavity, with the wedge-shaped tooth sized to engage the neck groove of the penile implant. The distal lock and the proximal lock of the rear tip extender advantageously increase the pull-off force between the rear tip extender and the penile implant by over <NUM>% compared to the engagement between a conventional rear tip extender and its penile implant. This advantage contributes to the added benefits of reducing or eliminating tissue ingrowth between the components to provide a system having improved explant capabilities.

One aspect of the system includes an embodiment where the annular protrusion of the distal lock is sized to engage with an entire circumference of the annular groove of the penile implant, and the proximal lock comprises a plurality of wedge-shaped teeth extending radially inward away from the interior wall of the cavity. The plurality of wedge-shaped teeth is distributed around a circumference of the cavity of the rear tip extender.

One aspect of the system includes the annular protrusion of the distal lock is sized to engage with an entire circumference of the annular groove of the penile implant, and the wedge-shaped tooth of the proximal lock is sized to engage with an entire circumference of the neck groove of the penile implant.

One aspect of the system includes the proximal portion of the penile implant further comprises a step section distal the annular groove, with the step section having a step diameter that is greater than the groove diameter; wherein, when the rear tip extender is coupled to the proximal portion of the penile implant, an exterior surface of the rear tip extender smoothly transitions and is co-planar to an exterior surface of the proximal portion of the penile implant.

One aspect of the system includes a joint formed at a location where the rear tip extender is coupled to the proximal portion of the penile implant, and the plurality of locks of the rear tip extender combine to prevent formation of a gap in the joint when a bending force is applied to the system.

One aspect of the system includes the neck groove of the proximal portion of the penile implant is formed by a junction between a portion of a spherical ball attached proximal to the tapered section, and the wedge-shaped tooth is sized to engage with the junction.

One aspect of the system includes the neck groove of the proximal portion of the penile implant is formed by a junction between a portion of a spherical ball attached proximal to the tapered section, and a diameter of the portion of the spherical ball is larger than a smallest diameter of the tapered section.

One aspect of the system includes the cavity of the rear tip extender includes a section of a spherical cavity located proximal to the wedge-shaped tooth and sized to receive the portion of the spherical ball.

One aspect of the system includes the penile implant is an inflatable penile implant attachable to a liquid reservoir and a pump by tubing.

One aspect of the system includes the proximal portion of the penile implant further comprises a first sphere that forms the proximal-most end of the penile implant and the neck groove of the penile implant is formed at a junction between the first sphere and the tapered section.

One aspect of the system includes the cavity of the rear tip extender is formed to include a spherical cavity sized to receive the first sphere of the proximal portion of the penile implant, and the wedge-shaped tooth of the proximal lock on the interior wall of the rear tip extender is formed by a surface of the spherical cavity and is adapted to engage the junction located between the first sphere and the tapered section.

One aspect of the system includes the rear tip extender further comprises a second sphere that forms a proximal-most end of the rear tip extender.

One aspect of the system includes the rear tip extender comprises a stackable rear tip extender (RTE), with an exterior wall of the stackable RTE comprising: an annular RTE groove formed around a circumference of the stackable RTE, a tapered RTE section proximal the annular RTE groove, with the tapered RTE section having a continuous reduction in diameter from the annular RTE groove toward the second sphere at the proximal-most end of the stackable RTE, and a neck RTE groove formed in the tapered RTE section at a junction between the second sphere and the tapered RTE section.

One aspect of the system further includes a plurality of the stackable RTEs, with the exterior wall of each of the plurality of the stackable RTEs comprising the annular RTE groove, the tapered RTE section, and the neck RTE groove.

One aspect of the system includes each one of the plurality of the stackable RTEs has a length that is different from a length of another one of the plurality of the stackable RTEs.

One aspect of the system includes the rear tip extender comprises a non-stackable rear tip extender (RTE), with an exterior wall of the non-stackable RTE comprising: a cylindrical section extending from a distal end of the non-stackable RTE in a direction toward the proximal-most end of the non-stackable RTE, a tapered RTE section proximal the cylindrical section, with the tapered RTE section having a continuous reduction in diameter from the cylindrical section to the second sphere at the proximal-most end of the non-stackable RTE, and a neck RTE groove formed in the tapered RTE section at a junction of the second sphere and the tapered RTE section.

One aspect of the system further includes a plurality of the non-stackable RTEs.

One aspect of the system includes each one of the plurality of the non-stackable RTEs has a length of the cylindrical section that is different from a length of the cylindrical section of another one of the plurality of the non-stackable RTEs.

<FIG> is a perspective view of one embodiment of an implantable penile prosthesis system <NUM>. The system <NUM> includes a penile implant <NUM> implantable into each corpus of the penis and a rear tip extender <NUM> (RTE <NUM>) attachable to the penile implant <NUM>. The RTE <NUM> advantageously allows a surgeon to adjust the length of the portion of the penile implant <NUM> that is implanted in the crus penis. One RTE <NUM> is shown since the surgeon decides which size of RTE <NUM> to attach to each one of the implants <NUM>.

The implantable penile prosthesis system <NUM> includes a pump <NUM> attached or attachable between the penile implants <NUM> and a reservoir <NUM>, for example with suitable tubing <NUM> connected between the pump <NUM> and the implants <NUM> and other like tubing <NUM> connected between the pump <NUM> and the reservoir <NUM>.

The pump <NUM> is provided to move liquid out from the reservoir <NUM> and into the penile implants <NUM>. One embodiment of the pump <NUM> includes a pump bulb, where squeezing of the pump bulb moves the liquid from the reservoir <NUM> into the implants <NUM>. The displaced liquid remains under pressure within the implants <NUM> to provide the implants with a rigidity sufficient for penetrative intercourse. A release pad <NUM> is provided on the pump <NUM> and pressing the release pad <NUM> displaces a valve stem inside the pump <NUM> to allow the pressurized liquid to return from the penile implants <NUM> back to the reservoir <NUM>. One suitable pump <NUM> is available from Coloplast Corp. , Minneapolis, Minnesota as part of an erectile dysfunction treatment product sold under the registered trademark TITAN penile prosthesis.

The reservoir <NUM> is sized to maintain a volume of liquid between about <NUM>-<NUM>. In one embodiment, the reservoir <NUM> is provided as a "cloverleaf" style of reservoir having multiple leaves that may be folded one against the other to compact the reservoir <NUM> for implantation into the abdomen of the user. One suitable reservoir <NUM> is sized to retain approximately <NUM> of liquid and is available from Coloplast Corp. , Minneapolis, Minnesota.

The RTE <NUM> is suitable for use with a malleable (or, not inflatable) penile implant or with an inflatable penile implant. The embodiment of the penile implant shown in <FIG> is an inflatable penile implant, which is inflatable with liquid from the reservoir <NUM> to achieve a stiffness suitable for penetrative intercourse. Each of the penile implants <NUM> include an inflatable cylinder <NUM> extending from a distal end <NUM> of a distal portion <NUM> of the implant <NUM> to a rear portion of the implant <NUM>. The rear portion of the implant <NUM> includes a proximal-most end <NUM> located on a proximal portion <NUM> of the penile implant <NUM>. A connection tube <NUM> is connected to the proximal portion <NUM> of the penile implant <NUM>, where the connection tube <NUM> is adapted to couple with the tubing <NUM> and provide a level of strain relief for the implant <NUM>.

The proximal-most end <NUM> (with or without the rear tip extender <NUM>) is implanted in the crus of the penis and the distal end <NUM> is implanted within the glans penis. The inflatable cylinders <NUM> are fabricated from material configured to collapse when the cylinders <NUM> are deflated to provide the penis with a flaccid state and expand (like a balloon) when the cylinders <NUM> are inflated with liquid to provide the penis with an erection. As a point of reference, the cylinders <NUM> are illustrated in an inflated state. Suitable material for fabricating the cylinders <NUM> includes silicone, biocompatible polymers such as urethanes, blends of polymers with urethane, copolymers of urethane, or the like.

<FIG> is a side view of one embodiment of the penile implant <NUM>. The penile implant <NUM> extends from the distal end <NUM> of the distal portion <NUM> of the implant <NUM> that is ultimately implanted into the distal part of the penis (the glans penis) to the proximal-most end <NUM> of the proximal portion <NUM> of the implant <NUM> that is ultimately implanted into the proximal part of the penis (the crus penis). The connection tube <NUM> is connected to the proximal portion <NUM> of the penile implant <NUM> and communicates internally with the inflatable cylinder <NUM>.

The proximal portion <NUM> of the penile implant <NUM> is configured and adapted to couple with the RTE <NUM>. The proximal portion <NUM> includes an annular groove <NUM> formed around a circumference of the penile implant <NUM>, where the annular groove <NUM> is formed (for example by molding or machining) to have a groove diameter Dg. A tapered section <NUM> is formed proximal the annular groove <NUM>, with the tapered section <NUM> having a reduction in diameter from the annular groove <NUM> toward the proximal-most end <NUM> of the penile implant <NUM>. The illustrated embodiment provides a continuous reduction in diameter for the tapered section <NUM> from the annular groove <NUM> toward the proximal-most end <NUM>, although other diameter reduction structures are acceptable. A neck groove <NUM> is formed in the tapered section <NUM> between the proximal-most end <NUM> of the penile implant <NUM> and the annular groove <NUM>. A step section <NUM> is formed distal the annular groove <NUM>, and the step section <NUM> is formed to have a step diameter Ds that is greater than the groove diameter Dg and less than a diameter Db of the base of the penile implant <NUM>. The step section <NUM> and the step diameter Ds allow a smooth transition from the base of the penile implant <NUM> to the RTE <NUM>.

The annular groove <NUM> is a recessed area that may be suitably formed as a U-shaped groove or a C-shaped groove. The neck groove <NUM> is a recessed area and can be formed in a variety of shapes, such as a U-shaped groove, a C-shaped groove, or a square-shaped groove with right angles.

The annular groove <NUM> and the neck groove <NUM> of the implant <NUM> provide engagement locations that allow durable connection with the RTE <NUM>. In a complementary manner, the RTE <NUM> is provided with a plurality of locks that engage with the annular groove <NUM> and the neck groove <NUM> of the implant <NUM>, which is described in greater detail below. The plurality of locks on the RTE <NUM> and the multiple engagement locations <NUM>, <NUM>, <NUM> on the proximal portion <NUM> of the penile implant <NUM> combine to provide a durable lock between the two components that resist separation of the RTE <NUM> from the implant <NUM>, even during an explant procedure.

<FIG> is a cross-sectional view of the rear tip extender <NUM>. Embodiments of the rear tip extender <NUM> provide a plurality of locks <NUM> within a cavity <NUM> of the RTE <NUM> that cooperate with the grooves <NUM>, <NUM> of the implants <NUM> to secure the RTE <NUM> to the implant <NUM>. The locks <NUM> combine to durably hold the rear tip extender <NUM> in place on the implant <NUM> in a way that beneficially resists separation, for example if the implant <NUM> is explanted years after implantation.

The RTE <NUM> extends a length L between a distal end <NUM> and a proximal end <NUM>. When the RTE <NUM> is coupled to the penile implant <NUM> (<FIG>), the RTE <NUM> provides an added effective length Le to the penile implant <NUM>, where the added effective length Le is measured from a proximal end of the cavity <NUM> to the proximal end <NUM> of the RTE <NUM>.

A variety of RTEs <NUM> may be provided with each RTE <NUM> having a different length L and a different added effective length Le. Surgeons have indicated a preference to have a selection of RTEs <NUM> available at the time of surgery and we describe RTEs <NUM> provided in increasing sizes of <NUM> increments (for example, a selection of RTEs with lengths Le sized from <NUM>, <NUM>, <NUM>, <NUM>, to <NUM>, etc.). In one embodiment, the RTE <NUM> is a three-dimensional conical body and includes a tapered diameter that tapers from a larger diameter at the distal end <NUM> to a smaller diameter at the proximal end <NUM>. The taper may be linear or a combination of non-tapered and tapered sections, as shown in <FIG>. One suitable material for fabricating the RTE <NUM> is silicone, for example a liquid silicone rubber, of a durometer between 50A - 70A Shore hardness.

The plurality of locks <NUM> include a distal lock <NUM>, a proximal lock <NUM>, and a cavity lock formed by the interior wall <NUM> of the cavity <NUM> at the distal end <NUM> that mates with the step section <NUM>.

The distal lock <NUM> is formed as an annular protrusion <NUM> extending radially inward away from the interior wall <NUM> of the cavity <NUM>. The annular protrusion <NUM> is sized to engage in a complementary way with the annular groove <NUM> (<FIG>) of the penile implant <NUM>.

The proximal lock <NUM> is formed as a plurality of wedge-shaped teeth <NUM> extending radially inward away from the interior wall <NUM> of the cavity <NUM>, where the wedge-shaped teeth <NUM> are sized to engage the neck groove <NUM> (<FIG>) of the penile implant <NUM>. The proximal lock <NUM> may be suitably molded as an integral part of the RTE <NUM> or may be an insert placed and retained inside of the cavity <NUM> of the RTE <NUM>. If the proximal lock <NUM> is an insert into the RTE <NUM> it is permanently connected to the RTE <NUM> using adhesives or chemical or mechanical bonding.

The cavity lock on the distal end <NUM> is provided to ensure the RTE <NUM> mates smoothly with the implant, and the mating of the cavity lock with the step section <NUM> (<FIG>) prevents tissue ingrowth at the mating location and resists bending forces from separating the RTE <NUM> from the proximal portion <NUM> of the implant <NUM>.

<FIG> is a perspective view of one embodiment of the proximal lock <NUM> provided in the form of an insert <NUM> insertable or moldable into the rear tip extender <NUM>. The proximal lock <NUM> includes a plurality of the wedge-shaped teeth <NUM> distributed around a circumference of the insert <NUM>.

In one embodiment, the insert <NUM> tapers from a larger diameter at a distal end <NUM> to a smaller diameter at a proximal end <NUM> and includes multiple recesses <NUM> formed in the proximal end <NUM>. The recesses <NUM> allow the insert <NUM> to flex as the proximal portion <NUM> (<FIG>) of the implant <NUM> is inserted into the RTE <NUM>, which ensures that the wedge-shaped teeth <NUM> firmly engage with the neck groove <NUM> of the implant (<FIG>). The plurality of the wedge-shaped teeth <NUM> are uniformly distributed around the perimeter of the proximal end <NUM> and are directed radially inward on the insert <NUM>. Each of the wedge-shaped teeth <NUM> have a base <NUM> that is wider than a pointed end <NUM> of the wedge-shaped tooth. The pointed edge <NUM> of each of the wedge-shaped teeth <NUM> is adapted to insert into and engage with the neck groove <NUM> of the implant <NUM> at four locations around the proximal portion <NUM> (<FIG>) of the implant <NUM>.

<FIG> is a perspective view of another embodiment of a proximal lock <NUM>' in the form of an insert <NUM>' that is insertable into the RTE <NUM>. The proximal lock <NUM>' is provided with a single wedge-shaped tooth <NUM>' extending around the circumference of the insert <NUM>'. The insert <NUM>' tapers from a larger diameter at a distal end <NUM>' to a smaller diameter at a proximal end <NUM>'. The tooth <NUM>' is located at the proximal end <NUM>' and extends radially inward toward a center of the insert <NUM>'. The pointed edge of the wedge-shaped tooth <NUM>' is adapted to insert into, for example by flexing, and engage around an entire circumference of the neck groove <NUM> of the implant <NUM>.

<FIG> is a side view of the RTE <NUM> positioned for attachment to the penile implant <NUM>, <FIG> is a side view of the RTE <NUM> connected with the penile implant <NUM>, and <FIG> is a schematic view of the plurality of locks <NUM> securing the RTE <NUM> to the penile implant <NUM>.

The surgeon usually measures the depth and width of the crus penis and the length of the distal (or external) penis before selecting a penile implant <NUM>. If the surgeon determines that the length of the implant should be increased, the surgeon will select a suitable sized RTE <NUM> and connect it to the implant <NUM>.

<FIG> illustrates alignment of the RTE <NUM> prior to engagement with the implant <NUM>. The long axis of the RTE <NUM> is aligned with the long axis of the implant <NUM> such that the distal lock <NUM> of the RTE <NUM> is oriented for engagement with the annular groove <NUM> of the implant <NUM> and the proximal lock <NUM> is oriented for engagement with the neck groove <NUM> of the implant <NUM>. <FIG> illustrates a typical alignment prior to the surgeon pressing the RTE <NUM> and the implant <NUM> together, where the press fitting can be aided by rotating or twisting the components relative to each other.

<FIG> and <FIG> provide two views of the plurality of locks <NUM> of the RTE <NUM> connected to the implant <NUM>. The annular protrusion <NUM> of the distal lock <NUM> of the RTE <NUM> is mated with the complementary annular groove <NUM> of the implant <NUM>, the wedge-shaped teeth <NUM> (<FIG>) of the proximal lock <NUM> are mated with the complementary neck groove <NUM> of the implant <NUM>, and the distal end <NUM> of the RTE engages with the step section <NUM> of the implant <NUM>. As connected, the effective length of the implant is increased by the addition of the RTE <NUM>.

<FIG> illustrates the uniform coupling of the RTE <NUM> to the implant <NUM> without a gap or space between the two components. The distal end <NUM> of the RTE <NUM> is structured to both engage and mate with the step section <NUM> of the implant <NUM> such that the exterior surface of the RTE <NUM> smoothly transitions and is co-planar to the exterior surface of the proximal portion <NUM> of the penile implant <NUM>. A joint <NUM> or an abutment <NUM> is formed at a location where the distal end <NUM> of the RTE <NUM> meets the step section <NUM> of the implant <NUM>. The plurality of locks <NUM> of the RTE <NUM> and the implant <NUM> combine to prevent the formation of a gap in the joint <NUM> when a bending force is applied to the implanted system <NUM> (<FIG>). The absence of a gap at the joint <NUM> between the RTE <NUM> and the implant <NUM>, even under a bending load, prevents tissue ingrowth at that area of the system. The reduced or eliminated tissue ingrowth at the joint <NUM> improves the structural integrity of the implanted implant <NUM> / RTE <NUM> to provide for efficient and effective explant of the implant <NUM> if the surgeon decides that is the proper eventual course of action.

Suitable dimensions for the RTE <NUM> are provided as an example. One suitable RTE <NUM> provides an added effective length Le of <NUM> when attached to the implant <NUM>. As noted above, a variety of RTEs <NUM> would typically be provided in a kit to accommodate adding an effective length Le (<FIG>) to the penile implant in increments of <NUM>. The proximal end <NUM> of the RTE <NUM> has a tip radius of <NUM>. The distal end <NUM> of the RTE <NUM> has an outside diameter of about <NUM> and is selected to smoothly match a diameter of the implant <NUM> measured at the step section <NUM>. Thus, the RTE diameter measured at the distal end <NUM> is selected to match the diameter of the proximal end portion <NUM> of the implant <NUM>, which can vary depending on whether the implant <NUM> is selected to be of a "narrow" size or a wider "standard" size.

The plurality of locks <NUM> of the RTE <NUM> and the implant <NUM> combine to resist pull-off of the RTE <NUM> from the implant <NUM> during an explant procedure. The prior style of rear tip extenders can, under some circumstances, be pulled-off its implant in response to a longitudinal pulling force of less than about <NUM> pounds force (less than about <NUM> Newtons). In a marked contrast, the plurality of locks <NUM> of the RTE <NUM> and the implant <NUM> improve the pull-off force by combining to resist a longitudinal pulling force in a range from about <NUM> pounds force to about <NUM> pounds force (in a range from about <NUM> Newtons to about <NUM> Newtons), which is an improvement in pull-off force for the RTE <NUM> over the prior rear tip extender by between <NUM>% and <NUM>%.

<FIG> is a schematic view of the system <NUM> implanted in a patient.

The groin area of the patient is shaved, antiseptically cleaned, for example with a surgical solution, and draped with a sterile drape. A retraction device, such as a surgical retractor sold under the trademark Lone Star and available from Lone Star Medical Products of Stafford, TX, is placed around the penis P. Thereafter, the surgeon forms an incision to access the corpora cavernosa of the patient, where suitable examples of incisions include either an infrapubic incision or a scrotal incision. The infrapubic incision is initiated between the umbilicus and the penis (i.e., above the penis), whereas the transverse scrotal incision is made across an upper portion of the patient's scrotum S. As an example of the transverse scrotal approach, the surgeon forms a <NUM>-<NUM> transverse incision through the subcutaneous tissue of the median raphe of the upper scrotum S and dissects down through the Dartos fascia and Buck's fascia to expose the tunicae albuginea of the penis P. Thereafter, each corpus cavernosum is exposed in a corporotomy where a small (approximately <NUM>) incision is formed to allow the surgeon to access and subsequently dilate each corpus cavernosum. The surgeon typically will insert an instrument (such as a blunt-ended scissors or other elongated tool) to separate a portion of the spongiosum material to open a path that allows insertion of a device to measure the proximal and distal length of each corpus cavernosum. Thereafter, each corpus cavernosum is dilated distally with a suitable expanding tool to create a space for the implant <NUM>. In one approach, the surgeon begins dilation of the penis by introducing an <NUM> dilator into the spongy tissue of the corpora and the crus with sequential progression to about a <NUM> dilator, each of which are introduced and pushed distally toward the glans penis and then proximally toward the crus of the penis, respectively. After suitable dilation of the space within the penis, the surgeon selects an implant <NUM> and adjusts the effective length by selecting an appropriately sized RTE <NUM>.

The surgeon inserts and directs the distal end <NUM> of each of the cylindrical the implants <NUM> into the distal-most portion of each corpus cavernosum. The proximal end <NUM> of the RTE <NUM> is implanted into each of the dilated proximal crus penis. The corporotomy is closed, and the remaining portions of the pump <NUM> and the reservoir <NUM> of the system <NUM> are implanted in the scrotum S and the abdomen A, respectively, of the patient.

The RTE <NUM> advantageously provides the surgeon with options in adjusting the effective length of the implant <NUM>. The locks <NUM> combine to secure the RTE <NUM> to the implant <NUM> in a way that resists the formation or opening of a gap at the joint <NUM> between the step section <NUM> and the distal end <NUM> of the RTE, particularly during bending or other stresses realized by the system <NUM> during use. Consequently, the RTE <NUM> remains durably connected to the implant <NUM> even if explanted.

<FIG> is a side view of one embodiment of a penile implant <NUM> suitable for use with the system of <FIG> and a non-stackable rear tip extender <NUM> (non-stackable RTE <NUM> or RTE <NUM>) attachable to the implant <NUM>. The RTE <NUM> is referred to as non-stackable because an exterior surface of the RTE <NUM> is generally smooth. The non-stackable RTE <NUM> has at most one lock feature provided by a spherical ball <NUM> at the end of the RTE <NUM>, and the spherical ball <NUM> is removable (for example by cutting the spherical ball <NUM> from the RTE <NUM>) to change the effective length of the non-stackable RTE <NUM>. The non-stackable RTE <NUM> is provided in a variety of lengths and the surgeon selects the single RTE <NUM> having the specific length the surgeon has determined to best fit the patient and the circumstances. The spherical ball <NUM> (described below) could be replaced by a non-spherical bulbous shape.

The penile implant <NUM> includes an inflatable cylinder <NUM> extending from a distal end <NUM> of a distal portion <NUM> of the implant <NUM> to a proximal-most end <NUM> of a proximal portion <NUM> of the penile implant <NUM>. A connection tube <NUM> is connected to the proximal portion <NUM> of the penile implant <NUM>, where the connection tube <NUM> is adapted to couple with the pump <NUM> and the tubing <NUM> (<FIG>) and provide a level of strain relief.

Like embodiments described above, the implant <NUM> includes two complementary locks in the form of an annular groove <NUM> and a neck groove <NUM> formed on either side of a tapered section <NUM>. The proximal portion <NUM> of the penile implant <NUM> is formed to include a first sphere <NUM> that forms the proximal-most end <NUM> of the penile implant <NUM> and the neck groove <NUM> of the penile implant <NUM> is formed at a junction <NUM> located between the first sphere <NUM> and the tapered section <NUM>. The implant <NUM> includes a step section <NUM> provided to receive a distal end of the RTE <NUM>; the step section <NUM> is sized to ensure a smooth planar transition between the RTE <NUM> and the implant <NUM>, when coupled together.

The annular groove <NUM> and the neck groove <NUM> of the implant <NUM> provide engagement locations that allow durable connection with the RTE <NUM>, and in a complementary manner, an interior of the RTE <NUM> is provided with a plurality of locks <NUM> that engage with the annular groove <NUM> and the neck groove <NUM>. The plurality of locks <NUM> inside the RTE <NUM> and the multiple engagement locations <NUM>, <NUM>, <NUM> on the exterior of the proximal portion <NUM> of the penile implant <NUM> combine to provide a durable lock between the two components that resist separation of the RTE <NUM> from the implant <NUM>, even during an explant procedure.

The RTE <NUM> extends a length L2 between a distal end <NUM> and a proximal-most end <NUM> and is configured to add an effective length L2e when connected with a penile implant. The RTE <NUM> forms an internal cavity <NUM> on an interior side that is opposite an exterior side of the RTE <NUM> that provides a second sphere <NUM> that forms the proximal-most end <NUM>. In one embodiment, the RTE <NUM> is a generally cylindrical shaped body formed around the cavity <NUM> with a larger diameter at the distal end <NUM> and a smaller diameter at the proximal end <NUM>. The added effective length L2e is measured between a proximal end of the internal cavity <NUM> to the proximal-most end <NUM>. Multiple stackable RTEs <NUM> could be packaged in a kit to provide the surgeon with a selection of differently sized RTEs <NUM> having <NUM> incremental added effective lengths L2e.

The plurality of locks <NUM> include a distal lock <NUM> and a proximal lock <NUM>.

The distal lock <NUM> is formed as an annular protrusion <NUM> extending radially inward away from an interior wall <NUM> of the cavity <NUM>. The annular protrusion <NUM> is sized to engage in a complementary way with the annular groove <NUM> of the penile implant <NUM>.

The proximal lock <NUM> is formed as a wedge-shaped tooth extending radially inward away from the interior wall <NUM> of the cavity <NUM>, where the wedge-shaped tooth is sized to engage the neck groove <NUM> of the penile implant <NUM>. The wedge-shaped tooth of the proximal lock <NUM> is formed at a location where an interior surface of a spherical portion <NUM> of the cavity <NUM> meets a tapered section <NUM> of the interior wall <NUM> and is an annular wedge-shaped tooth <NUM>. The proximal lock <NUM> is suitably molded as an integral part of the RTE <NUM> between the spherical portion <NUM> and the annular protrusion <NUM> of the interior wall <NUM>. The spherical portion <NUM> could be replaced by a non-spherical cavity shape that is sized to receive the non-spherical bulbous shape <NUM>.

The spherical portion <NUM> of the cavity <NUM> is sized to receive the first sphere <NUM> of the proximal portion <NUM> of the penile implant <NUM>, and the wedge-shaped tooth of the proximal lock <NUM> of the RTE <NUM> is adapted to engage the junction <NUM> formed between the first sphere <NUM> and the tapered section <NUM> of the implant <NUM>.

The RTE <NUM> extends a length L2 between the distal end <NUM> and the proximal-most end <NUM>, and one suitable length for L2 is provided in a range from about <NUM> to about <NUM>. In one embodiment, the second sphere <NUM> has a sphere diameter of about <NUM> and the surgeon is provided with instructions for removing the second sphere <NUM> (for example by cutting), which results in the RTE <NUM> having an effective length that is <NUM> (or a half centimeter) shorter than the originally sized L2 of the RTE <NUM>. Thus, the RTE <NUM> is customizable to an effective length in a range from about <NUM> to about <NUM>.

<FIG> is a side view of a plurality (for example, six RTEs <NUM>) of non-stackable rear tip extenders RTEs <NUM> each individually suitable for attachment to the penile implant <NUM>. Each of the non-stackable RTEs <NUM> has the cavity <NUM> identified in <FIG>, where the cavity <NUM> mates with the plurality of locks <NUM> (the distal lock <NUM> and the proximal lock <NUM>).

Each of the non-stackable RTEs <NUM> is provided with a length L3, L4, L5, L6, L7, and L8, as examples, with L3 < L4 < L5 < L6 < L7 < L8. The non-stackable RTEs <NUM> are sized so that each one of the non-stackable RTEs <NUM> provides the surgeon a different half-centimeter (<NUM>) incremental added effective length L2e (<FIG>). In one embodiment, the implant <NUM> is provided with a selection of different length non-stackable RTEs <NUM> packaged together in a kit of parts <NUM> with instructions for use.

During an implant procedure the surgeon may discover that one or both proximal crus penis recesses in the patient are fibrotic or otherwise blocked or possibly longer than expected. The surgeon will measure each crus penis and select an appropriate one of the different length non-stackable RTEs <NUM> and attach it to the implant <NUM> by engaging the cavity <NUM> of the RTE <NUM> with the proximal portion <NUM> of the implant <NUM> (<FIG>). As noted above, each of the different length non-stackable RTEs <NUM> includes the second sphere <NUM> that is suited for placement at the proximal location of the crus penis. Alternatively, the second sphere <NUM> of the non-stackable RTE <NUM> may be removed by cutting to adjust the effective length of the selected RTE <NUM> by an approximately <NUM> increment. In this manner, the kit of parts <NUM> allows the surgeon to select and accurately provide a suitably sized implant <NUM> / RTE <NUM> for most patient conditions encountered during most surgeries.

The interior surface of the RTE is provided with the plurality of locks <NUM> and an exterior surface of the non-stackable RTE <NUM> is characterized by an absence of multiple locking features. Thus, a single non-stackable RTE <NUM> may be connected to the implant <NUM> to adjust the length of the implant <NUM>, but an additional one of the non-stackable RTE <NUM> is not suited for attachment to an attached RTE <NUM>, and this is what is meant by non-stackable RTE <NUM>.

The non-stackable RTE <NUM> has an exterior wall <NUM> having a cylindrical section <NUM> extending from the distal end <NUM> in a direction toward the second sphere <NUM> at the proximal-most end, a tapered RTE section <NUM> proximal the cylindrical section <NUM>, with the tapered RTE section <NUM> having a continuous reduction in diameter from the cylindrical section <NUM> to the second sphere <NUM>, and a neck RTE groove <NUM> formed in the tapered RTE section <NUM> at a junction of the second sphere <NUM> and the tapered RTE section <NUM>. The absence of multiple locking features on the exterior of the non-stackable RTE <NUM> means that the RTE <NUM> could be attached to the implant <NUM>, but could also be easily removed, which is not desirable for an implanted rear tip extender that might eventually be explanted.

<FIG> is a side view of one embodiment of a stackable rear tip extender <NUM> (stackable RTE <NUM> or RTE <NUM>) attachable to the implant <NUM> and suitable for use with the system of <FIG>.

Like the embodiments described above, the implant <NUM> includes two complementary locks in the form of the annular groove <NUM> and the neck groove <NUM> formed on either side of the tapered section <NUM>. The proximal portion <NUM> of the penile implant <NUM> is formed to include the first sphere <NUM> that forms the proximal-most end <NUM> of the penile implant <NUM> and the neck groove <NUM> of the penile implant <NUM> is formed at the junction <NUM> between the first sphere <NUM> and the tapered section <NUM>. The step section <NUM> is provided to receive the distal end of the RTE <NUM>, where the step section <NUM> is sized to ensure a smooth planar transition between the RTE <NUM> and the implant <NUM>.

In this embodiment, the interior surface of the RTE <NUM> is provided with a plurality of locks and an exterior surface of the stackable RTE <NUM> is provided with multiple locking features. Thus, each stackable RTE <NUM> may be connected to the proximal portion <NUM> of the implant <NUM> or connected to another already attached stackable RTE <NUM>, and this allows stacking RTEs <NUM> together to arrive at a specific selected effective length for the implant.

The RTE <NUM> extends a length L3 between a distal end <NUM> and a proximal-most end <NUM> and is configured to add an effective length L3e when connected with a penile implant. The RTE <NUM> forms an internal cavity <NUM> formed by an interior wall <NUM> that is opposite an exterior surface <NUM> of the RTE <NUM>. The exterior surface <NUM> of the RTE <NUM> includes a second sphere <NUM> that forms the proximal-most end <NUM> of the RTE <NUM>. In one embodiment, the RTE <NUM> is a generally cylindrical shape formed around the cavity <NUM> with a larger diameter at the distal end <NUM> and a smaller diameter at the proximal end <NUM> and the second sphere <NUM>. The added effective length L3e is measured between a proximal end of the internal cavity <NUM> to the proximal-most end <NUM>. Multiple stackable RTEs <NUM> could be packaged in a kit to provide the surgeon with a selection of differently sized RTEs <NUM> having <NUM> incremental added effective lengths L3e.

The RTE <NUM> is formed to have a plurality of locks <NUM> inside the cavity <NUM> and a plurality of locks <NUM> formed on the exterior wall <NUM>.

The plurality of locks <NUM> inside the cavity <NUM> include a distal lock <NUM> and a proximal lock <NUM>.

The distal lock <NUM> is formed as an annular protrusion <NUM> extending radially inward away from the interior wall <NUM> of the cavity <NUM>. The annular protrusion <NUM> is sized to engage in a complementary way with the annular groove <NUM> of the penile implant <NUM>.

The proximal lock <NUM> is formed as a wedge-shaped tooth <NUM> extending radially inward away from the interior wall <NUM> of the cavity <NUM>, where the wedge-shaped tooth <NUM> is sized to engage the neck groove <NUM> of the penile implant <NUM>. The wedge-shaped tooth <NUM> of the proximal lock <NUM> is formed at a location where an interior surface of a spherical portion <NUM> of the cavity <NUM> meets a tapered section <NUM> of the interior wall <NUM> and is an annular wedge-shaped tooth <NUM>.

The spherical portion <NUM> of the cavity <NUM> is sized to receive the first sphere <NUM> of the proximal portion <NUM> of the penile implant <NUM>, and the wedge-shaped tooth <NUM> of the proximal lock <NUM> of the RTE <NUM> is adapted to engage the junction <NUM> formed between the first sphere <NUM> and the tapered section <NUM> of the implant <NUM>.

One suitable added effective length L3e for the RTE <NUM> is in a range from about <NUM> to about <NUM>. In one embodiment, the second sphere <NUM> has a sphere diameter of about <NUM> and the surgeon is provided with instructions for removing the second sphere <NUM> (for example by cutting), which results in the RTE <NUM> having an added effective length L3e that is <NUM> (or a half centimeter) shorter than the originally sized RTE <NUM>. Thus, the RTE <NUM> is customizable to an added effective length L3e in a range from about <NUM> to about <NUM>.

The exterior wall <NUM> of the stackable RTE <NUM> includes an annular RTE groove <NUM> formed around a circumference of the stackable RTE <NUM>, a tapered RTE section <NUM> proximal the annular RTE groove <NUM>, with the tapered RTE section <NUM> having a continuous reduction in diameter from the annular RTE groove <NUM> toward the second sphere <NUM> at the proximal-most end <NUM> of the stackable RTE <NUM>, and a neck RTE groove <NUM> formed in the tapered RTE <NUM> section at a junction between the second sphere <NUM> and the tapered RTE section <NUM>.

Thus, the plurality of locks <NUM> formed on the exterior wall <NUM> include portions of the annular RTE groove <NUM>, the tapered RTE section <NUM>, the second sphere <NUM>, and the neck RTE groove <NUM>. The RTE <NUM> is a stackable rear tip extender because each annular RTE groove <NUM> is adapted to engage with the annular protrusion <NUM> of another RTE <NUM>; the tapered RTE section <NUM> is adapted to engage with the tapered section <NUM> of another RTE <NUM>; the second sphere <NUM> is adapted to fit inside of the spherical portion <NUM> of the cavity <NUM>; and the neck RTE groove <NUM> is adapted to engage with the wedge-shaped tooth <NUM> formed inside the cavity <NUM>.

<FIG> is a side view of multiple stackable rear tip extenders 504a, 504b, 504c each suitable for attachment to each other and suitable for attachment to the penile implant <NUM>.

The plurality of the stackable RTEs 504a, 504b, 504c each has the exterior wall <NUM> formed to include the annular RTE groove <NUM>, the tapered RTE section <NUM>, and the neck RTE groove <NUM>. In one embodiment, each one of the plurality of the stackable RTEs 504a, 504b, 504c provides an added effective length L3e that is different from an added effective length L3e of another one of the plurality of the stackable RTEs. In one example, the added effective length L3e of RTE 504a is less than the added effective length L3e of RTE 504b, and the added effective length L3e of RTE 504b is less than the added effective length L3e of RTE 504c. One suitable added effective length L3e for RTE 504a is about <NUM>; one suitable added effective length L3e for RTE 504b is about <NUM>; and one suitable added effective length L3e for RTE 504c is about <NUM>. Each sphere <NUM> of each RTE <NUM> is removable by cutting to reduce an effective length of each RTE <NUM> by about <NUM>, which the surgeon might find helpful when accurately sizing a final length of an implant for a patient.

Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of medical devices as discussed herein.

Claim 1:
An implantable penile prosthesis system (<NUM>) comprising
a penile implant (<NUM>) comprising a proximal portion (<NUM>) implantable in a crus penis, and a rear tip extender (<NUM>), with the proximal portion of the penile implant comprising:
an annular groove (<NUM>) formed around a circumference of the penile implant to define a groove diameter,
a tapered section (<NUM>) proximal the annular groove, with the tapered section having a continuous reduction in diameter from the annular groove toward a proximal-most end of the penile implant,
characterised by
a neck groove (<NUM>) formed in the tapered section between the proximal-most end of the penile implant and the annular groove; and the rear tip extender forming a cavity (<NUM>) sized to receive the proximal portion of the penile implant, with the cavity defined by an interior wall provided with a plurality of locks (<NUM>) comprising:
a distal lock (<NUM>) formed as an annular protrusion extending radially inward away from the interior wall of the cavity, where the annular protrusion is sized to engage with the annular groove of the penile implant, and
a proximal lock (<NUM>) formed as a wedge-shaped tooth extending radially inward away from the interior wall of the cavity, with the wedge-shaped tooth sized to engage the neck groove of the penile implant.