Patent Description:
Ileostomy and colostomy are common operations which may be necessitated, for example, by malignancy or chronic bowel inflammation. The surgery is called an ileostomy if the colon and rectum are removed and a colostomy if the rectum alone is removed. Similarly an abdominal urostomy is created when the urinary bladder has to be removed due to, for example, bladder cancer. In these operations, a stoma is formed in the abdominal wall to which a bowel segment is connected.

Ostomy is a generic term for any such procedure where a stoma is created.

The stoma, in most cases, has to be connected to a bag for the collection of bodily waste. However, instead of a conventional ileostomy, it is possible to make a reservoir known as a "Kock pouch" from the distal part of the ileum. The pouch is formed in such a way that a nipple valve is created which serves to close the reservoir, whilst allowing it to be drained intermittently by means of a catheter. This is an example of a so-called continent ileostomy (CI) and it was formerly an attractive alternative to conventional ileostomy but is now rarely used. The complexity of the procedure and the high potential for complications - most of them related to dysfunction of the continence nipple valve - has deterred many surgeons from adopting the operation today.

The ileopouch anal anastomosis (IPAA) is today the gold standard worldwide for these patients but, as with a Cl, this operation is also risky and failures are common, mostly leading to pouch excision with loss of bowel. Conversion of a failed IPAA to a Cl would be a preferable option but, again, surgeons are reluctant to perform this complex and unreliable technique. Likewise, conversion of a malfunctional orthotopic neobladder or Bricker urostomy would be desirable.

In its earlier patent application <CIT>, the present applicant disclosed a percutaneous ostomy implant comprising a solid-walled cylindrical body and an anchoring section in the form of a circular flange. The device was designed to be implanted through the abdominal wall and secured by an anchoring section located below the fascia, above the muscle layer. This section comprised inner and outer concentric rings interconnected by S-shaped members in order to provide an axially resilient structure which could absorb shear stresses and consequently reduce the risk of tissue damage. Spaces around the S-shaped members and the provision of numerous apertures in the rings allowed for tissue ingrowth and vascularisation. It was proposed to connect the device to the side of the bowel wall and by providing a removable lid on the cylindrical body a continent ostomy could be provided.

<CIT> discloses another solid-walled implant. This was provided with a fabric coating comprising Dacron velour which was intended to encourage tissue ingrowth.

A development of this implant was disclosed in <CIT> in which the solid-walled cylindrical body was replaced by an axially outer tubular part spaced from the anchoring section by circumferentially-spaced legs. The tubular part penetrated the skin and formed a ring for connection to a bag or lid. This implant was designed to receive a bowel section drawn up through it; the spaces between the legs allowed the generation of a tissue bond between the inner part of the abdominal wall and the serosal tissue of the bowel in order to provide a more secure, stable, leak-proof and well-vascularised tissue-implant junction. In some embodiments, a circumferential ingrowth mesh was additionally provided. This extended along most of the length of the tubular part with an annular gap being provided between it and the tubular part to facilitate growth of serosal tissue through the mesh.

In a further development, disclosed in <CIT>, the present applicant proposed a cylindrical body formed of two axially-spaced tubular parts. The outer tubular part penetrated the skin and provided a connecting ring. The inner tubular part was attached to an anchoring flange of the type previously described. The two parts were connected together by a "distance means" comprising either radially-spaced legs or a rigid cylindrical ingrowth mesh which allowed for the generation of a tissue bond between the abdominal wall and the bowel. By means of this arrangement, a break was provided in the possible infection path along the implant from the skin.

In a still further development, the applicant disclosed in <CIT> a percutaneous ostomy implant comprising a cylindrical part for mounting an external detachable device, a cylindrical ingrowth mesh and a circular flange for anchoring the implant. The cylindrical part and circular flange were attached to opposite ends of the ingrowth mesh, with the mesh extending inside the cylindrical part. The implant was configured such that when it is implanted in the abdominal wall of a patient, abdominal tissue including the epidermis meets the ingrowth mesh and is able to attach therethrough directly to serosal tissue of a bowel segment inside the implant. Thus, it was based on the hypothesis that by allowing the epidermis to attach directly to the serosal tissue, bacterial infection (i.e. bacterial attachment to implant surface and subsequent migration) can be prevented.

However, whilst this implant was found to be effective in ensuring sound attachment of the serosal tissue to the abdominal tissue, it had a drawback in that it became more difficult to ensure a fluid-tight seal between the exterior parts of the implant and the bowel segment. This was because the implant relied upon the bowel segment extending within the cylindrical part and maintaining secure infiltration of serosal tissue through the mesh inside that part to form a good seal to the implant. If the bowel receded below the cylindrical part, a leakage path could be formed through the mesh, even if the bowel segment and abdominal wall remained integrated and the implant remained secure and free of infection.

<CIT> discloses a stoma stabilising device intended to prevent stomas from constricting over time and hence requiring surgical re-opening. The preferred embodiments comprise a flexible mesh tube with a radially extending mesh anchoring flange. In some variants, multiple layers of mesh may be employed.

In <CIT>, the applicant presented further developments relating to percutaneous ostomy implants comprising a connecting member, a first tubular ingrowth member and a second tubular ingrowth member radially outwardly spaced from the first tubular ingrowth member, a radially-extending dermal anchor to engage the abdominal wall beneath the dermis, and/or a tubular ingrowth member arranged around the connecting member. This implant was formed by a laser cutting process.

However, in trials, this implant was still found to have problems. For example, this implant was fixed to the muscle sheath with an anchor provided at the bottom. This was not ideal with patients adding or losing weight since the implant height was fixed and the thickness of a patient's abdomen could vary over time. There was also insufficient ingrowth at the top of the implant. These factors could lead to skin problems, implant overgrowth, excessive implant protrusion and leakage from the system.

<CIT> discloses an implant formed from a hollow, tubular body surrounded by a rigid porous tubular mesh.

<CIT> discloses an implant formed from a tubular body with an anchoring flange, wherein a number of holes are provided in the anchoring flange and tubular body.

In a first aspect, the present invention relates to a percutaneous ostomy implant comprising a tubular interior section for implantation into a patient and an exterior section connected to the interior section, a surface of the exterior section comprising a rigid three-dimensional porous structure at an inner circumference thereof, characterized in that the thickness of any member forming the porous structure is less than or equal to <NUM> and/or the maximum diameter of any opening in the porous structure is <NUM>.

By providing a three-dimensional porous structure at an inner surface of the exterior section, this provides a ingrowth means into which tissue can grow. By providing a three-dimensional structure, this can provide better and more secure ingrowth than previously used two-dimensional ingrowth means. A three-dimensional ingrowth porous structure can provide a "skeleton" structure for tissue ingrowth and creates a physiological need that promotes cellular ingrowth into the structure. Furthermore, by providing the three-dimensional porous structure at the exterior section, this can lead to more ingrowth at the outer end of the implant, making it more secure at the exterior end and reducing the possibility of leakage from the system.

Preferably, there is no gap between the three-dimensional porous structure and the rest of the exterior section.

The porous structure is preferably connected to the rest of the exterior section at least at first and second end regions thereof, and/or preferably at a number of points over the height of the porous structure.

Preferably, the porous structure extends to an exterior end (top) of the exterior section. In this way, a bowel segment, for example, may be secured by ingrowth right up to the top end of the implant, thereby providing a more secure implantation of the implant and also reducing the likelihood of leakage. Alternatively, the porous structure may extend to within <NUM>, <NUM> or <NUM> of the exterior end (top) of the exterior section.

The implant is a percutaneous ostomy implant, which is suitable for implantation into the abdominal wall of a patient.

The tubular interior section may be substantially cylindrical but may be of generally any form with an opening along a longitudinal axis thereof. The opening should ideally be large enough for a bowel segment to pass therethrough.

The shape and/or size (e.g. the internal and/or external diameter) of the cross-section of the interior section may vary along its length.

The exterior section may be generally ring-shaped, tubular or cylindrical, for example.

The exterior and/or interior sections may have a substantially circular cross-section.

The exterior section is ideally coaxial with the interior section.

The exterior section may have an outer diameter (measured from its outer edges) of <NUM>-<NUM>, more preferably <NUM>-<NUM> or <NUM>-<NUM>.

The exterior section may have an inner diameter (measured from its inner edges) of <NUM>-<NUM>, more preferably <NUM>-<NUM> or <NUM>-<NUM>.

The interior section may have an inner diameter (measured from its inner edges) at its narrowest point of <NUM>-<NUM>, more preferably <NUM>-<NUM> or <NUM>-<NUM>.

Implants whose exterior and interior sections have a smaller inner diameter (i.e. towards the lower ends of the scales mentioned above) may be particularly useful for urostomies. Implants whose exterior and interior sections have a larger inner diameter (i.e. towards the upper ends of the scales mentioned above) may be particularly useful for colostomies.

The interior and exterior sections may have circular cross-sections or any other shape. Thus, since the cross-sections of these sections need not necessarily be circular, references to "diameter" above refer to the maximum distance measured perpendicularly across the sections.

Preferably, the interior and exterior sections have the same cross-section (e.g. in size and/or shape), at least at the point where the sections meet.

The porous structure is preferably arranged around the entire inner circumference of the exterior section. Alternatively, the porous structure may be provided around at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>% or at least <NUM>% of the inner circumference of the exterior section. By providing all, or at least a significant part of the inner circumference of the exterior section with a porous structure, this ensures that ingrowth means is provided around all, or at least a significant part, of the inner circumference of the exterior section so secure and sufficient ingrowth may be obtained.

The porous structure preferably has a thickness (or a minimum thickness) of at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, or at least <NUM>. In preferred embodiments, the porous structure has a thickness of around <NUM> or <NUM>. By providing a porous structure of at least <NUM> (or greater) thick, this means that the porous structure may be formed of a number of layers (e.g. two or three layers) and helps to ensure secure ingrowth into the porous structure. The thickness of the porous structure may be measured in a radial direction with respect to the longitudinal axis of the implant.

The porous structure should ideally also be thin enough that there is enough space inside the exterior section for a bowel segment to pass through it. Thus, preferably the porous structure has a thickness of <NUM> or less, <NUM> or less, or <NUM> or less. The thickness of the porous structure may be in a range of <NUM> to <NUM>, <NUM>, or <NUM>, for example.

Preferably, the porous structure is completely permeable and has no dead ends. For example, each passage entering the porous structure ideally also has an exit. Alternatively, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, or at least <NUM>% of the openings into the porous structure have a corresponding exit. This can provide the most secure ingrowth into the ingrowth means.

The thickness of any member forming the porous structure is preferably less than or equal to <NUM>, less than or equal to <NUM>, less than or equal to <NUM>, less than or equal to <NUM>, or less than or equal to <NUM>. The thickness of any member forming the porous structure is preferably greater than or equal to <NUM>, greater than or equal to <NUM>, greater than or equal to <NUM>, or greater than or equal to <NUM>. By providing a porous structure formed of members with such dimensions, this means that the porous structure has dimensions which are biologically comfortable (mimicking coral, for example), thereby creating a physiological need which promotes secure ingrowth of tissue into the porous structure.

For similar reasons, preferably, the maximum diameter of any opening in the porous structure is <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. The minimum diameter of any opening in the porous structure may be <NUM>, <NUM>, <NUM> or <NUM>, for example. The diameters of any openings (or of at least <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>% or <NUM>% of the openings) in the porous structure are preferably in a range of <NUM> to <NUM>, more preferably, <NUM> to <NUM>, more preferably <NUM> to <NUM>, more preferably <NUM> to <NUM>.

The cross-sections of any members and/or openings in the porous structure may be circular or any other regular or irregular shape such as elliptical, superelliptical, quadratic with rounded corners, hexagonal, octagonal, polygonal, polygonal with rounded corners, or rectangular with rounded corners, for example. Thus, since the cross-sections of the members and/or openings forming the porous structure need not necessarily be circular, references to "diameter" above refer to the maximum distance measured perpendicularly across a member and/or an opening in the porous structure.

In further optimised embodiments, both the members forming the porous structure and the openings of the porous structure may vary independently in size and/or shape within one porous structure, in a random or structured (regular) pattern.

The porous structure preferably has a height of at least <NUM>, at least <NUM>, at least <NUM>, or at least <NUM>, where the height is the length of the porous structure measured in a direction parallel to the longitudinal axis of the implant.

The porous structure preferably has a height of less than <NUM>, less than <NUM>, less than <NUM> or less than <NUM>.

Preferably, the height of the porous structure is in a range from <NUM> to <NUM>, more preferably from <NUM> to <NUM>, more preferably from <NUM> to <NUM>, more preferably from <NUM> to <NUM>.

In a preferred embodiment, the height of the porous structure is <NUM>.

The porous structure has a height that is ideally great enough to provide a sufficiently large ingrowth zone, but also small enough that there is limited implant protrusion above skin level (the porous structure being ideally located within the exterior section).

However, in some embodiments the porous structure may extend into the interior section and/or a further porous structure (for example with any of the features discussed in relation to the first porous structure) may be provided in the interior section. Thus, a porous structure with a height of up to around <NUM> may be provided. Such a porous structure could extend from the exterior section into the interior section.

The porous structure may be flexible, semi-flexible or rigid.

The porous structure is preferably integral with the rest of the exterior section. This means that the exterior section, at least, can be formed as a single element (for example with the rest of the implant as well) and there is no need to attach a porous structure inside the exterior section.

The porous structure is preferably made from a biologically acceptable material such as titanium. This helps to prevent patients reacting adversely to the implant. Preferably, a commercially pure titanium is used such as medical grade <NUM> titanium. Examples of other materials that could be used include titanium grades according to ASTM F67 (ISO <NUM>) medical grade <NUM>, <NUM>, <NUM>, <NUM> or <NUM>, specifically grade <NUM> Ti64ELI, other biocompatible metals and alloys such as Elgiloy, or a chromecobalt-molybdene alloy, biocompatible ceramics and biocompatible polymers.

The porous structure may be formed from interconnecting members. The members may be arranged in layers (e.g. concentric layers), for example. The layers could be connected by connecting members. Accordingly, the connecting members will typically have a radial extent. These are preferably two to four layers, but more preferably three.

The members may form a regular, repeating pattern throughout the porous structure. For example, the porous structure could be formed from a plurality of repeating units.

Alternatively, the porous structure may have an irregular or partly irregular structure.

In either case it will be appreciated that the porous structure is porous in multiple directions (i.e. passages through the structure extend in multiple directions) so that a coral-like structure is provided. This is in contra-distinction from conventional mesh which is essentially two-dimensional, with porosity (and passageways) extending in only one direction, relative to the surface of the mesh.

Preferably, the exterior section comprises engagement means (e.g. a engagement mechanism) for engaging with a device. For example, the exterior section may comprise one or more grooves, recesses or indentations into which corresponding attachment means provided on a lid or other device may be attached. Preferably, the engagement means are located on an exterior surface of the implant, or at the very top of the inner surface of the implant, so that tissue inside the implant is not affected when a device is attached to the implant.

Alternative engagement means include: a threaded interface for screwing a device onto the implant, a bayonet attachment, a magnetic interface (i.e. one or more magnets arranged on the implant), a rubber or rubber-like material encompassing the outer perimeter, or like a cork in the inner diameter, for example, of the implant.

In some embodiments, at an inner end, the interior section may comprise a radially extending part, for example in a cone or trumpet-like shape. This can help to secure the implant in a patient's body as it can resist forces acting on the implant in more directions.

Alternatively or additionally, the implant may comprise an anchoring flange extending radially outwardly from the interior section. This can also help to secure the implant in a patient's body.

The anchoring flange may extend to a greater radius than the radially extending part (if both such components are provided).

The anchoring flange may extend perpendicularly from the implant. However, it is preferred that it extends at an angle of less than <NUM>° such that it is sloping towards the interior end of the implant. The anchoring flange may be curved. These features can allow the anchoring flange to follow the general curvature of a patient's body, reducing the likelihood of damage or problems caused by its implantation.

The anchoring flange may be formed of or comprise an ingrowth means (e.g. an ingrowth part) such as a mesh, e.g. a hexagonal mesh. Such an ingrowth means can allow body tissue to grow into the flange and secure the implant in the body.

The interior section preferably extends longitudinally inwardly (i.e. downwardly as shown in the figures) from a point at which the anchoring flange is connected to it. The interior section may additionally or alternatively extend longitudinally outwardly (i.e. upwardly as shown in the figures) from a point at which the anchoring flange is connected to it.

The implant may be flexible, semi-flexible or rigid. In some embodiments the flexibility/rigidity of the implant may vary over its structure. For example, the interior section may be more flexible than the exterior section so that, for example, the interior section is more adapted to the surrounding tissue, but the exterior section is still sufficiently rigid that a lid may be attached to it. This may be achieved by using different materials in different sections of the implant, for example. Such different materials could be joined with welds, glue, friction, threads, or other techniques.

The interior section may be formed of or comprise an ingrowth means (e.g. an ingrowth part) such as a mesh, e.g. a hexagonal mesh. Such an ingrowth means can allow body tissue to grow into the interior section and secure the implant in the body.

The interior section may comprise a plurality of rods, the rods having a diameter of less than or equal to a biologically comfortable length such as <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. The diameter of the rods is preferably similar to the average diameter of human skin hairs, e.g. <NUM> to <NUM>. By forming the interior section, or part of the interior section, from such thin components, the amount of material used to form the implant can be minimised, thereby reducing the likelihood of a patient reacting adversely to the implant. Furthermore, since the rods have a diameter of less than or equal to a biologically comfortable length, this reduces the possibility of the patient's body rejecting or reacting adversely to the implant.

There may be provided an implant comprising a tubular interior section for implantation into a patient and an exterior section connected to the interior section, wherein the interior section comprises a plurality of rods and the rods have diameters of less than or equal to <NUM>, less than or equal to <NUM>, less than or equal to <NUM>, less than or equal to <NUM>, less than or equal to <NUM>, less than or equal to <NUM> or less than or equal to <NUM>. The diameters of the rods may be in a range of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM>, for example.

Preferably, the rods have a diameter of greater than or equal to <NUM>, greater than or equal to <NUM>, greater than or equal to <NUM>, or greater than or equal to <NUM>. In a preferred embodiment, the rods have a diameter of <NUM>.

The rods may have a circular cross-section or any other shape. Thus, since the cross-sections of the rods need not necessarily be circular, references to "diameter" above refer to the maximum distance measured perpendicularly across a rod.

The rods are preferably arranged circumferentially around the implant. At least some of the rods may be parallel to the longitudinal axis of the implant, for example.

Depending on the diameter of the rods and the material from which they are made, ideally sufficient rods should be provided to make the implant strong enough to withstand pulling forces acting on it, with a safety margin, for example. The stronger the material used for forming the rods, the smaller the number of rods required. Ideally, the smallest number of rods possible are used to keep the amount of material used to a minimum.

More than <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM> rods may be provided and/or fewer than <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> rods may be provided.

Preferably, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM> rods are provided.

One or more of the rods is preferably slanted with respect to the longitudinal axis of the implant. This can help to improve the mechanical strength of the implant since such rods can help to withstand torque, shearing and compressing forces acting on the implant. For example, the one or more slanting rods may be arranged at an angle of up to <NUM>°, up to <NUM>°, up to <NUM>°, up to <NUM>°, up to <NUM>°, up to <NUM>°, up to <NUM>° or up to <NUM>° with respect to a longitudinal axis of the implant. Preferably, the one or more slanting rods may be arranged at an angle of at least <NUM>°. In preferred embodiments, one or more slanting rods are arranged at angles of up to <NUM>°.

Rods may be slanted radially inwardly or outwardly from the longitudinal axis of the implant and/or circumferentially or sideways around the implant. The inward or outward radial slant of the rods is preferably less than the circumferential slant. For example, rods may be slanted radially outwards or inwards by an angle of around <NUM>° or less, and/or rods may be slanted circumferentially by an angle of around <NUM>° or less. Rods may be slanted circumferentially in clockwise and/or anticlockwise directions (when view from the top or exterior end of the implant).

One or more of the rods is preferably parallel with respect to the longitudinal axis of the implant. Such parallel rods can help to withstand axial forces acting on the implant along its longitudinal axis, for example.

Around <NUM>-<NUM>%, <NUM>-<NUM>%, <NUM>-<NUM>%, <NUM>-<NUM>% or more of the rods may be slanting.

Around <NUM>-<NUM>%, <NUM>-<NUM>%, <NUM>-<NUM>%, <NUM>-<NUM>% or more of the rods may be parallel.

One or more rods may have at least one end located radially inwardly with respect to the implant compared to one or more other rods. Such an arrangement can improve the mechanical strength of the implant, particularly with respect to shear forces. Shear forces may act on an implant, for example, when a patient rises from a chair and contacts a table with the implant, moves sideways and contacts a door-post, or similar situations.

The inner ends of the rods (i.e. the ends of the rods located furthest from the exterior section of the implant) are preferably all located at the same radius of the implant.

The exterior ends of the rods (i.e. the ends of the rods located closest to the exterior section of the implant) may be located at different radii, for example at two or three different radii. In a preferred embodiment, the exterior ends of the rods are located on three imaginary concentric circles. Preferably, the concentric circles are equally spaced.

The radial distance between the radially innermost exterior ends and the radially outermost exterior ends may correspond to the thickness of the porous structure. For example, the radial distance between the radially innermost exterior ends and the radially outermost exterior ends may be around <NUM> to <NUM> or <NUM>.

Such arrangements of the rods can result in a very rigid, box-like overall structure, which can help to increase the mechanical strength of the implant and distribute the forces acting on the exterior section of the implant more uniformly into the porous structure.

The rods are ideally long enough that, in use, they can extend through the skin (i.e. the epidermis and the dermis) and also ideally extend partially into the hypodermis. For example, the rods may be at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM>, at least <NUM> or at least <NUM> long. The rods may have a maximum length of <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. In a preferred embodiment, the rods are around <NUM> long. Of course, the slanting rods may be slightly longer than the parallel rods. The lengths referred to in this paragraph may refer to the slanting or the parallel rods.

The interior section may comprise an inner interior section part and an outer interior section part.

The outer interior section part preferably comprises the plurality of rods.

The plurality of rods may connect the inner interior section part to the exterior section.

Preferably, the inner interior section part is connected to the exterior section solely by the plurality of rods. This helps to minimise the amount of material used in the implant.

For similar reasons, the outer interior section part is preferably formed solely from the plurality of rods.

The inner interior section part preferably comprises or is formed of an ingrowth means (e.g. an ingrowth part), preferably in the form of a mesh such as a hexagonal mesh. By providing such an inner interior section part, this can help the implant to be implanted securely into a patient's body.

After an implant has been implanted into a patient, it is important that a bowel segment, for example, or other vessel passing through the implant, is secured so that it can grow into the implant.

There are various ways in which the bowel segment, for example, may be secured or fixated. One conventional method is a surgical procedure referred to as a "turnbull". During this procedure, on a conventional stoma the efferent part of the intestine is wrung inside out and attached to the skin surrounding the stoma. However, after this procedure, the stoma often retracts at skin level, leaving a space and resulting in leakage. Also, it is not possible to perform a conventional turnbull with the implant of the above aspects because this would completely cover and hide the implant. It would then not be possible to use a stabiliser device (to hold the implant in position) during healing and it would also not be possible to monitor the healing and ingrowth of the implant. The risk of bodily waste being caught under the turnbull and around the implant would be great, potentially causing infection, and it would not be possible to clean and wash away such trapped waste. In previous processes with an ostomy implant, the intestine was simply left outside the implant or arranged into a "loose hanging turnbull", not connected to anything, and not secured or fixed.

There is therefore a need for providing a way of securing the bowel segment, for example, to provide a more stable environment for the stoma to heal after an ostomy is performed on a patient.

There may be provided an adaptor for securing a bowel segment outside a patient's body after an ostomy has been performed, the adaptor comprising: attachment means (e.g. an implant attachment part) for attaching the adaptor to an implant; and securing means (e.g. a bowel segment securing part) to which a bowel segment may be attached.

By providing such an adaptor, a turnbull procedure may be facilitated and the bowel segment can be secured whilst it heals, thereby reducing the likelihood of it retracting during this process. In addition, when used with an implant according to one of the aspects of the invention described above, the bowel segment can be secured close to the porous ingrowth structure (where this is provided in the exterior section of the implant), which further helps to keep the bowel segment in a fixed position, and thereby provides an optimal peaceful healing situation free from significant movements or mechanical stress.

The adaptor may be referred to as a turnbull adaptor.

The implant itself may also be secured with a stabiliser device to hold it in place during healing.

The adaptor should ideally be easy to attach to the implant with the correct alignment.

Preferably, the attachment means are arranged to prevent the adaptor from moving rotationally, horizontally and vertically with respect to the implant, when the adaptor is attached to the implant. This helps to prevent rotational or other forces acting on the vessel during healing.

Preferably, the attachment means are arranged to attach to an outer surface of the implant, for example in a groove, recess or indentation on an outer surface of the implant. The attachment means may be arranged to engage with one or more corresponding grooves, recesses or indentations on the implant.

In a preferred embodiment, the attachment means comprises one or more resilient members. This is a simple way of allowing the adaptor to be attached to an implant. The one or more resilient members may comprise engagement means (e.g. implant engagement parts), such as protruding parts, for engaging with the implant, for example in one or more corresponding recesses on the implant.

Alternative attachment means could also be used. For example, longer or shorter resilient members could be used with corresponding grooves, recesses or indentations, for example, in a correspondingly lower of higher position on the implant. Different shaped protruding parts could also be used. Other alternatives include: a threaded interface for screwing the adaptor onto the implant, a bayonet attachment, a magnetic interface (i.e. one or more corresponding pairs of magnets on the adaptor and the implant), a rubber or rubber-like material encompassing the outer perimeter of the implant and/or an inner perimeter of the adaptor using only friction forces, a rubber or rubber-like material with a ring-like suction-cup on the adaptor for attaching to a polished top surface, for example, of the implant.

The adaptor preferably has an aperture through which the bowel segment may pass. For example, the adaptor may be substantially ring-shaped. Preferably the aperture has the same shape and/or diameter as the inner shape and/or diameter of the corresponding implant. For example, the adaptor may be substantially ring-shaped or tubular. The aperture may have a diameter of <NUM>-<NUM>, more preferably <NUM>-<NUM> or <NUM>-<NUM>.

The securing means may comprise one or more openings in the adaptor through which sutures may be attached. For example, the adaptor may comprise one or more radially extending parts in which the one or more openings are provided. The securing means could alternatively comprise one of more hooks to which sutures may be attached.

The adaptor is preferably made of a plastics material such as a medical quality polyamide. Alternatively, the adaptor may be made of medical grade POM, PEEK, or other similar polymer, a semi-rigid or flexible medical grade polymer such as Mediprene or similar, or titanium or other metal or alloy, depending on the attachment mechanism and manufacturing method.

In some embodiments, a biologically degradable material is used to form the adaptor. The adaptor would then "disappear" automatically after a suitable time, as it is dissolved by the surrounding tissue. Such an adaptor could be made of a medical grade polymer such as PGA poly(glycolide), PDO poly(p-dioxanone), LPLG poly(L-lactide-co-glycolide), DLPLG poly(DL-lactide-co-glycolide) or PHB-PHV copolymer (polyhydroxybutyrate-polyhydroxyvalerate), for example.

Different polymers or other materials will degrade at different rates within the body and therefore a polymer or other material should ideally be used which has a suitable release/degradation rate. For example, a material which could form an adaptor that would degrade after a few weeks (e.g. <NUM>-<NUM> or <NUM>-<NUM> weeks) may be suitable. Such an adaptor would remain in the body long enough for the healing process to take place. Also, factors such as mechanical properties, processing properties, possible sterilisation methods, cost and availability of the material, etc. should be considered when selecting a suitable material. The adaptor is preferably arranged to receive the bowel segment therethrough and allow the bowel segment to be reverted back over the adaptor.

According to a further aspect of the invention, there is provided a kit comprising the implant according to the invention and an adaptor for securing a bowel segment outside a patient's body after an ostomy has been performed, the adaptor comprising: attachment means for attaching the adaptor to the implant; and securing means to which a bowel segment may be attached.

The adaptor in the kit may be as described in relation to the adaptor aspect of the invention or any of its preferred features above.

The implant in the kit may be as described in relation to any of the implant aspects of the invention or any of their preferred features above.

The implant is preferably used or provided in combination with a lid to prevent leakage and/or to protect the stoma. However, it may also be used in combination with a bag or an evacuation device. Preferably, the implant is integrally formed. Alternatively, the implant may be made in parts which are subsequently joined together. The parts may be formed from the same material or two or more different materials.

The implant may be formed by a 3D printing process, for example. Preferably, an electron beam or a laser 3D printing process is used. Alternatively, the implant, or parts thereof, may be moulded or conventionally machined and laser or water-jet cut, or produced by etching and/or punching methods.

Preferred embodiments of the invention will now be described by way of example only and with reference to the accompanying drawings, in which:.

<FIG> show an embodiment of an implant <NUM>.

The implant <NUM> is formed of an interior section <NUM> and an exterior section <NUM>. When implanted in a patient, the interior section <NUM> is located mostly or entirely inside the patient whereas the exterior section <NUM> is located mostly or entirely outside of the patient.

The interior section <NUM> is formed of an inner interior section part <NUM> and an outer interior section part <NUM>.

The inner interior section part <NUM> is a substantially cylindrical structure formed of an hexagonal mesh. At its lower (as shown in the figures) or inner end, the cylinder flares radially outwardly in a radially extending part 4a and is terminated by a continuous solid ring <NUM>.

An anchoring flange <NUM> extends radially outwardly from the inner interior section part <NUM>. This is also made of an hexagonal mesh. The anchoring flange <NUM> has at its radially outer edge a continuous solid ring <NUM>. The inner interior section part <NUM> extends both above and below (i.e. outwardly and inwardly from) the anchoring flange <NUM>.

The anchoring flange <NUM> extends to a greater radius than the radially extending part 4a.

The outer interior section part <NUM> connects the inner interior section part <NUM> to the exterior section <NUM>. The outer interior section part <NUM> is formed from a number of rods <NUM> extending between the inner interior section part <NUM> and the exterior section <NUM>. The rods <NUM> are arranged circumferentially around the implant <NUM>.

Some of the rods <NUM> are slanted with respect to the longitudinal axis of the implant <NUM> and others are parallel with it. The slanted rods are angled so that they can withstand rotational forces acting on the implant <NUM>. The rods which are parallel with the longitudinal axis of the implant <NUM> are for withstanding loads acting on the implant <NUM> longitudinally.

Some of the rods <NUM> have an exterior end which is located radially inwardly compared to the exterior ends of other rods <NUM>. The interior ends of the rods <NUM> are all located at the same radius of the implant <NUM>.

The rods <NUM> have a maximum diameter of <NUM> and a length of around <NUM>. The slanting rods are slightly longer than the parallel rods.

The exterior section <NUM> is ring-shaped and has an outer circumferential groove <NUM> to which part of a lid or a connector (e.g. to a bag or other device) or other device may be attached.

The exterior section <NUM> also has three indentations <NUM> into which an adaptor (such as the turnbull adaptor described below) or other device may be attached. The indentations <NUM> are arranged at equally spaced intervals around the outer circumference of the exterior section <NUM>.

The interior surface of the exterior section <NUM> is formed from a three-dimensional porous structure <NUM> (not shown in detail here), such as porous structure <NUM> or <NUM> described below.

All elements of the implant <NUM> are integral with each other and made from the same material. The implant <NUM> is formed entirely of titanium.

The implant <NUM> is manufactured using a laser 3D printing process. After the implants <NUM> have been printed using the laser 3D printing process, the outer surface of the exterior section <NUM> is polished to give a smooth finish.

Alternatively, the implant <NUM> may be moulded and/or made in parts which are subsequently joined together.

<FIG> show an embodiment of an implant <NUM> with a larger inner diameter than the implant <NUM> of <FIG>.

However, like the implant <NUM> of <FIG>, the implant <NUM> is also formed of an interior section <NUM> and an exterior section <NUM>. The interior section <NUM> is formed of an inner interior section part <NUM> and an outer interior section part <NUM>.

The inner interior section part <NUM> has a radially extending part 104a which is terminated by a continuous solid ring <NUM>.

An anchoring flange <NUM> extends radially outwardly from the inner interior section part <NUM> and has at its radially outer edge a continuous solid ring <NUM>.

The outer interior section part <NUM> is formed of a number of rods <NUM> extending between the inner interior section part <NUM> and the exterior section <NUM>.

The exterior section <NUM> has an outer circumferential groove <NUM> and three indentations <NUM>. The interior surface of the exterior section <NUM> is formed from a three-dimensional porous structure <NUM>.

Other features of the implant <NUM> described above apply equally to the implant <NUM>.

<FIG> shows a porous structure <NUM>. As shown in <FIG>, the porous structure <NUM> is in the form of a hollow cylinder or tube located at an inner surface of the exterior section <NUM>.

The implant <NUM> shown in <FIG> is generally similar to the implants <NUM> and <NUM> described above so its structure will not be described in detail. The only difference to implant <NUM> is that there are no indentations on the exterior section <NUM>.

The implant <NUM> is formed of an interior section <NUM> and an exterior section <NUM>. The interior section <NUM> is formed of an inner interior section part <NUM> and an outer interior section part <NUM>.

The inner interior section part <NUM> has a radially extending part 204a which is terminated by a continuous solid ring <NUM>.

The exterior section <NUM> has an outer circumferential groove <NUM> but no indentations. The interior surface of the exterior section <NUM> is formed from the three-dimensional porous structure <NUM>.

The porous structure <NUM> is completely permeable; there are no dead ends. Every passage entering the porous structure also has an exit. The maximum thickness of any member forming the porous structure is <NUM> and the maximum diameter of any opening is also <NUM>.

<FIG> show a part of the porous structure <NUM> in more detail. It is formed from interconnecting members <NUM>. The members <NUM> are arranged in layers <NUM> which are connected by connecting members <NUM>.

In the embodiment shown, the members <NUM> and <NUM> form a regular, repeating pattern throughout the porous structure <NUM>. However, in other embodiments, the porous structure has an irregular structure. The apertures in the porous structure have substantially square, rectangular or cross-shaped cross-sections. However, in alternative embodiments, some or all of the apertures are circular or oval.

<FIG> show an example of another porous structure <NUM>. This porous structure <NUM> is made up of a number of repeating sub-units <NUM>. Each of the sub-units <NUM> is formed of four members <NUM> joined together at a central point of the sub-unit <NUM> at ends thereof. Six sub-units <NUM> are joined together to form a generally hexagonal ring or unit <NUM>. The units <NUM> are then joined together in a regular repeating fashion to form the porous structure <NUM>.

<FIG> show an adaptor <NUM> for securing a bowel segment outside a patient's body after an ostomy has been performed.

The adaptor <NUM> is formed of a flattened ring <NUM> with a short cylindrical part <NUM> protruding in a first direction from an inner diameter of the ring <NUM>. Three resilient members <NUM> protrude from the ring <NUM> in an opposite direction to the cylindrical part <NUM>.

The resilient members <NUM> are arranged equally spaced around the ring <NUM> and each member <NUM> has a protruding part <NUM> located on a radially inward side of the resilient member <NUM> and towards an end of the resilient member <NUM> away from the ring <NUM>.

The ring <NUM> has a number of slot-shaped apertures <NUM> (in this case, twelve) arranged around it circumferentially.

As shown in Figs. <NUM> to <NUM>, the adaptor <NUM> can be attached to the exterior section <NUM> of an implant <NUM>. The protruding parts <NUM> of the resilient members <NUM> fit into the indentations <NUM>, thereby attaching the adaptor <NUM> to the implant <NUM> and preventing it from moving both rotationally, transversally and longitudinally with respect to the implant <NUM>.

When attached, the adaptor <NUM> and the implant <NUM> have a common axis and the adaptor <NUM> is sized such that it can fit over and be attached to the implant <NUM>. The inner diameter of the adaptor <NUM> and the exterior section <NUM> of the implant <NUM> are the same.

The adaptor <NUM> is made entirely of plastic and is fabricated in a laser sintering process from medical quality polyamide powder (PA2200).

The adaptor <NUM> is sterilised by means of autoclaving and is provided sterile. Alternatively, the adaptor <NUM> may be sterilised by radiation, gas such as ethylene oxide, plasma or other methods.

The adaptor <NUM> is provided in different sizes, for example two sizes, to fit different sized implants (i.e. implants with different diameters).

The adaptor <NUM> is intended to be used during the surgical procedure when implanting an implant such as one described above. When attached to the implant <NUM>, the adaptor <NUM> can receive the bowel segment therethrough and allow the bowel segment to be reverted back over the adaptor <NUM>.

The adaptor <NUM> can be used to fix the efferent intestine for around <NUM> to <NUM> weeks after implantation, in order to provide best possible stress-free healing and in-growth conditions for the ileum during the integration process with the implant.

The adaptor <NUM> is attached to the exterior section <NUM> of the implant <NUM> at the end of the implantation procedure. It is used to secure the efferent intestine with a few sutures, during the first four to six weeks after implantation. Thereafter, the efferent intestine is cut away and the adaptor <NUM> is removed.

In order to use the adaptor <NUM>, the following steps are performed:.

After a few weeks the intestine should have grown enough into the implant <NUM> for the adaptor <NUM> to be removed. The part of the intestine protruding outside the implant <NUM> will now have started to wizen and is cut away. The adaptor <NUM> is removed and the intestine will reside permanently just at the top of the implant <NUM>.

Claim 1:
A percutaneous ostomy implant (<NUM>, <NUM>, <NUM>) comprising a tubular interior section (<NUM>, <NUM>, <NUM>) for implantation into a patient and an exterior section (<NUM>, <NUM>, <NUM>) connected to the interior section (<NUM>, <NUM>, <NUM>), a surface of the exterior section (<NUM>, <NUM>, <NUM>) comprising a rigid three-dimensional porous structure (<NUM>, <NUM>, <NUM>, <NUM>) at an inner circumference thereof
characterized in that the thickness of any member forming the porous structure (<NUM>, <NUM>, <NUM>, <NUM>) is less than or equal to <NUM> and/or the maximum diameter of any opening in the porous structure is <NUM>.