ADM has long been used as a soft tissue replacement therapy in the field of wound healing and tissue repair and reconstruction(16). Commonly, the use of ADM to repair wounds has been combined with skin graft or negative-pressure wound therapy (NPWT)(17, 18). A handful of studies indicate regeneration of full-thickness skin defects using ADM, and without skin graft or flap surgery(19–21). PELNAC, a double-layer structure of ADM, is generally used as a pretreatment before skin grafting, which can improve the survival rate of skin grafting and accelerate the wound healing(22). We once treated a case of hand trauma with a skin defect on the palm. However, the patient did not take the doctor's advice on undergoing the second skin-grafting surgery. And when he kept his next outpatient appointment with us approximately 50 days later, we found that the wound had been healed. From this, it is arguably that ADM can not only serve as an anatomical dressing, but also has the ability to stimulate wound repair. The possible mechanism of it is that ADM, which is similar to the dermal reticular structure, reduces the accumulation of collagen, induces angiogenesis and remodel the structure and function of the dermis(23).
In this article, we show that ADM can replace skin graft and flaps to promote the regeneration of full-thickness skin defects. Although the contraction of the wound cannot be completely avoided due to the poor extensibility of the skin at these injured sites, it can still be suggested that the wound is healed by regeneration. Furthermore, we found that PELNAC has certain anti-infective ability. Although at first sight, the wound appears to resemble skin necrosis or pus formation after being covered with PELNAC for a period of time, it then starts to get drier and eventually promotes the would regeneration. This is consistent with the results of our current animal experiments that the infection rate of the wound will be reduced after the use of ADM.
Compared with skin and flaps, ADM presents some distinct advantages. Firstly, patients treated with ADM are unconstrained by donor supply or damage. All volunteers do not need to take skin and flaps from other parts of the body. Secondly, although wound healing time for ADM treatment was longer than that skin graft or flaps surgery, the overall course of disease outcome was not significantly different between two therapeutic methods. We analyze the reason was that all patients treated by ADM acquired one-stage healing and did not require a second operation, thus the average time for postoperative recovery was reduced. Lastly, quality of wounds treated with ADM were better than the skin or flaps surgery arm. Comparison between afflicted and healthy limbs indicate comparable passive (or active) motion of lower limb joints. In addition, the regenerated skin was noted to heal to a fine appearance and feel.
Specimens were not sampled from healed wounds, thereby limiting further pathological analysis. However, previous work conducted at our laboratory found concomitant hair regeneration(20) for a few wounds treated with ADM(20). These rat studies showed the infiltration of stem cells following treatment, with detailed mechanism of action requiring further work.
In conclusion, for select patients, 1-stage Pelnac reconstitution can be considered as a novel method for inducing regrowth of epidermis and hair follicles, thus warranting further research.