ADM refers to human or animal skin which has had all of the cells removed such that it leaves behind just a collagen scaffold. It is inert and the body does not reject it because the body does not recognise it as foreign. The body then populates this scaffold with its own cells and “incorporates” it into the body.
Plastic surgeons in Australia are excited as there are now many alternatives for ADM’s on the market which were not previously available. They have been around in various forms internationally for many years but it is only recently that we have been able to freely access these products which are now fully approved by the TGA. Their main uses are in implant breast reconstruction and hernia repairs. I am going to concentrate on the breast reconstruction side of things to simplify the discussion. All of the following products should really be classified as matrices not ADM’s as you will see that not all are derived from skin.
HD Flex – Human derived dermis of skin – soft pliable and flexible
Alloderm – Human derived dermis (Not freely available in Australia)
Stratis – Porcine derived dermis of skin – thicker and less pliable
Veritas – Bovine Pericardium – thin soft and pliable
Seri – Silk derived mesh
You might say that’s all good and well but what is it’s use?? They should be thought of as a biologic substitute to the muscle covering over a tissue expander. When a tissue expander is placed after a mastectomy it is most commonly placed under the pectoralis major muscle of the chest wall. This muscle layer tends to be much tighter than the skin envelope and limits the amount of fluid or air that can be inflated immediately. This subsequently gives a poorer initial and sometimes long term outcome and means more inflations. If we can add a matrix in as a substitute then the initial results will be better and allow more volume to be inserted at the time of mastectomy.Another upside is that is also allows for a one stage direct to implant (DTI) reconstruction in select cases. The downside is that there is a higher infection rate of between 3-5 % which can be significant and so in my opinion these matrices should be used sparingly.