<qa>  What is the cutaneous model SASS created by the LOEX?The hypothesis of this trial is that the cutaneous model SASS, a dermal epidermal skin substitute, created by the LOEX could be as high-performant, or even better, than the ones already existent in North America for the wound care. We anticipate showing on 6 patients that ulcer that did not close with conventional treatment, will heal or at least improve with this treatment. 