CA1048205A - Implantable prosthesis having a removable fixation means - Google Patents

Abstract

Abstract of the Disclosure This is a prosthesis which can be implanted in the human body and has easily removable fixation means.
The prosthesis includes a container, an attachment means and the fixation means. The attachment means is engageable with the fixation means by one or more loops.

Description

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There are several specific methods for restoring or improving normal body contour to th~ female breast either for cosmetic or support reasons. Two of these methods of achieving the required result are the use of an external removable prosthesis attached to the body by a harness ;
arrangement or an implanted prosthesis. ~ ~ -Originally implanted prostheses were made from foam type materials, which tended to absorb body fluids and were susceptible to invasion by blood vessels and fibrous tissue that advantageously fixed the prosthesis in position but unfortunately caused the prosthesis to lose resiliency ` and to change in size. In the case of a breast prosthesis ~-resilience is very important to most wearers.
The Pangman U.S. Patent 2,842,775 issued July 15, 1958 utilizes a breast implant having an external wall o~
foam material, a wall of impermeab~e material and an inner ~; core of foam material, surrounded by the wall of impermeable material. The theory being that although the external wall will be invaded by blood vessels the wall of imperm~able material will prevent the invasion from continuing into the inner core.
~ The patent to T. D. Cronin, U.S. 3,293,663 issued ; December 27, 1966 discloses a breast prosthesis having a layer of porous material adhered by daubs of cement to the container. The porous material positions the container allowing tissue ingrowth and anchoring the prosthesis to the chest wall. The porous material may be cut in patches and ., .
adhered to different positions on the container.

~14~ 5 In other known implantable prosthetic devices, loops of material are used in some cases as anchoring means to prevent rotation. In such devices it is common surgical practice to suture the loop of material to retain the implant in position.
There are presently two schools of thought concerning anchoring of implantable prostheses. Some surgeons use an implant anchoring means; others do not.
Surgeons who favor the latter approach maintain that omitting the anchoring means provides a more resilient result without any considerable incidence of the implant moving away from the chest wall. All of the prostheses known to the applicant either have anchoring means attached to the envelope or container of the prosthesis in such a manner that it would be very difficult to remove or do not have any anchoring means. This state of affairs requires manufacturers, distributors, and hospitals to maintain ;~
inventory of both types of prostheses.
This invention is directed to an augmentation -prosthesis comprising (1) a flexible container approximating the shape of the cavity to be filled, ~2) an attachment ., .
pad adhered or otherwise attached to the rear wall of the container having attachment means as50ciated with the pad `~
and (3) anchoring means which may be removably engaged ;
with the attachment pad. ~`
An object of the present invention is to pro~ide an implantable prosthesis which may be quickly converted from one with anchoring means to one without anchoring means.
Another object of the present invention is to provide an implantable prosthesis having an attachment pad

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engaged therewith the attachment pad having loops for engaging anchoring means.
Thus, in accordance with the present teachings, an implantable prosthetic device is provided for use in an animal body. The device includes a container which has an external surface with attachment means being assoaiated with the external surface which has tissue permeable anchoring means connected thereto. The attachment means includes at least one loop which is engageable with the anchoring means and is easily separable from the attachment means and which has a width less than the width of the external surface.
Other objects and attendant advantages of the present invention will become obvious to those skilled in the art from a reading o~ the following detailed description , when read in conjunction with the accompanying drawings wherein:
FIG. 1 is a sectional view showing a type of prosthesis in place in a human breast.
FIG. 2 is a top pLan view of the prosthesis shown in FIG. 1 including the anchoring strip showing portions of `~ 20 the anchoring strip in broken line to show engagement with the attachment pad.
FIG. 3`is a side elevation of the prosthesis shown i~ FIG. 2.
FIG. 4 is a top plan view o~ the prosthesis shown in FIG. 2 showing the loops of the attachment pad covered with tape.
FIG. S is a top plan view of the prosthesis shown in FIG. 2 with the anchoring strip only engaged to one loop.
; In the drawings there is shown a mammary prosthesis `~
comprising an envelope or container 10 filled with a gel 12.
The envelope 10 is formed of a flexible silicone rubber membrane and the gel 12 is a semi-fluid methyl silicone capable of .;tt , ~L~4~
having a consistency which will prov.ide resiliency and maintains the proper contour of the container 10. The container 10 could be of the type which can be inflated at the time of implantation such as disclosed in U.S. Patent 3,683,424. The container 10 can be formed in several ways '. ':

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such as by a dip process on a mandral, by vacuum forming or by assemhly of a cup portion to a back wall utilizing vulcanization or adhesion to join the two parts~
The container may be formed o~ a physiological inert elastomeric material which includes several plastics -~ although it is preferred to use one of the family of silicone rubbers. Under certain circumstances organic rubbers made from butyl polymer or the natural polymer from the hevea tree could be utilized. The silicone rubbers which may be used 10 in this invention can be either of the heat vulaanizing or ~-room temperature vulcani7ing type. Since these rubbers are ; intended for medical purposes, fillers, vulcanizing agents and other constituents should be chosen for their non-toxic, physiological inert characteristics.
A pad or attachment means 14 made of a flexible, physiological inert material such as the material used to form the container is adhered or otherwise attached to the . ~ .
;~ rear wall 16 of the container 10. If desired, material ~ from which the pad 14 is made may be reinforced. The pad -; 20 14 may have a rectangular, oval or other convenient shape and is fairly thin. The pad 14 includes a series of spaced loops 18 in transverse relation to the longitudinal axis o~ the pad 14. Each loop is ~ormed by a pair of spaced, parallel slits, and is contiguous to the plane of the pad 14.
The loop 18 can be bowed awa~ from the plane and the remaining portion of the pad 14 allowing an anchoring means in the form of an anchoring strip 20 to be inserted thereunder. The anchoring strip 20 may be made of any toxicologically acceptable, open lattice work such as sponge, mesh or felt. -i~ 30 Using the invent~r's prosthesis the surgeon may ~ implant it with the anchoring strip 20 if he desires ingrowth ' ~

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~4t~2~5 or remove the anchoring strip and place the loops 18 in their contiguous position if he does not desire ingrowth.
If desired, tape 22 formed of physiologically inert material may be placed over the loops 18 in their contiguous position to assure that accidental anchoring with the loops does not take place.
As shown in FXG. 1 of the drawings if anchoring is desired by the surgeon the loops 18 are engaged to the anchoring strip 20 and over a period of time tissue from the chest wall, in the case of a mammary prosthesis, will grow into the interstices of the open lattice work, preventing inadvertent or undesired migration of the prosthesis. I~
the doctor should not desire a total anchoring or should desire to suspend the prosthesis he can cut the anchoring means so that only the upper loop engages it and the lower two loops are pushed against the body of the container.
On the other hand, he may desire to do this with the bottom loop or the bottom two loops only.
Another possibility is that after removal of the anchoring means a small amo~mt of implantable medical adhesive can be placed under the loop and the loop pushed against the container, thereby preventing tissu~ ingrowth.
When anchoring is desired, the doctor may secure the implant to adjacent tissue using absorbable sutures, ; thereby holding the implant in a desired position and location until ingrowth takes place.
Obviously the container may be shaped to support animal body contouring such as the buttocks, hips, testicles, or in cases of pectus excavatum, the chest. ;

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Claims (2)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An implantable, prosthetic device for use in an animal body including a container having an external surface, attachment means associated with the external surface and the attachment means having tissue permeable anchoring means connected thereto, the attachment means including at least one loop engageable with the anchoring means and the anchoring means easily separable from the attachment means and having a width less than the width of the external surface.

2. A prosthetic device as set forth in claim 1 wherein the anchoring means is formed of a thin sheet of physiological inert material and is rectangular in configuration.