Mesh graft

The larger the meshes and the corresponding grid or mesh spacing or expansion, the longer the re-epithelialization of the grafted wound. Reepithelialization occurs starting from the edges of the grafted split skin, with keratinocytes confluent in the skin gaps. The gaps in the meshed graft allow drainage of wound secretions, preventing the risk of seroma or hematoma formation under the skin graft. Consistent immobilization of the grafted areas to avoid shear forces is a prerequisite for safe healing of the skin grafts. Shear forces prevent the capillaries from sprouting into the transplanted skin, which can survive only about 3-5 days without its own blood supply via diffusion processes from the wound. Prevention of shear forces can be achieved by using an overknot dressing or by applying negative pressure therapy over the graft.

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The disadvantage of the mesh graft is that a cosmetically and functionally unfavorable result is often achieved because the mesh texture remains permanently visible. Too much removed split skin can be wrapped in a sterile compress moistened with NaCL at 4°C in the refrigerator, stored in a sterile container, and still transplanted 7-10 days later. Therefore, a possible donor site that is sometimes forgotten is the skin of amputated extremities, which can be used for defect coverage with a time delay.

Fixation of the sheet graft is by either staples, sutures, or fibrin glue, and there are combinations of all three fixation techniques. The fixation technique has no effect on the postoperative outcome. In contrast, an overknot or negative pressure dressing has an effect on the graft success. In an overknot dressing, opposing sutures of approximately 10-15 cm in length are applied to the wound edges. A foam pad, cut to fit the size of the wound, is applied to the thin layer of fat gauze overlying the graft and then secured to the pad under compression by tying the ends of the sutures.

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Meek technique

One surgical option to circumvent the problem of limited donor area is greater expansion of split skin. In the so-called Alexander technique, the expanded split skin is combined with foreign skin. Thus, expansion rates of the meshed split skin up to 1:9 are possible, although rarely performed. An alternative technique to expand the split skin is the method according to Meek. This method, which is safe to use for large expansion rates of the split skin, is established in many burn centers worldwide because of its simpler grafting and lower fragility compared with the large mesh grafts, and is preferred to the mesh graft technique for very large burns. Raff et al. also demonstrated that up to a burned body surface area of 75%, the remaining unburned skin is sufficient as a donor area and only needs to be used once to avoid additional application of cultured skin. Cicero Parker Meek (1914 – 1979) worked as a general surgeon at Aiken County Hospital in South Carolina, USA, whose special interest was the treatment of severely burned patients. In his article “Successful Microdermagrafting using the Meek-Wall Microdermatome” published in the American Journal of Surgery in 1958, he described for the first time a device-based method for producing “postage stamp-like” small skin grafts. His basic reasoning was that the keratinocytes of grafted skin islands confluence from the graft margin to the periphery. From this, he concluded that the longer the margins of the grafts, the faster the wound healing of transplanted areas would have to be.

One week after Meek grafting, the nylon pleats are carefully peeled off and foreign skin is grafted over the adherent nonconfluent islets. In another 1994 article on the Meek technique by Kreis et al, the authors compared the expansion rates of mesh and Meek grafts in an in vitro experiment and concluded that an expansion of 1:6 using the mesh technique was equivalent to an expansion of 1:4 using the Meek technique. A further modification was published by Raff et al. in 1996. The authors stated that for expansion rates up to 1:6, additional transplantation of foreign skin is not necessary. In 1997, at the suggestion of surgeon Robert Kreis, pleats with an expansion rate of 1:3 were produced for the first time. The last modification was made in 2001 by Dr. Abdul Reda Lari from the Al Babtain Burn Center in Kuwait City. He had the idea of replacing the pneumatic motor (which drives the 13 blades) with a hand crank, as compressed air is not available in many countries, making the device more affordable for emerging and developing countries. The Meek technique allows definitive wound management by split-thickness skin grafting up to a burned body surface area of 75% without additional grafting of cultured skin [3,9]. Surgical treatment may be necessary in several steps due to intraoperative blood loss in extensive burns. Depending on the patient’s constitution and intensive medical preparation (up-transfusion), coverage of up to 25% VKOF with simultaneous necrosectomy is possible in one surgical session. Higher coverage rates can be achieved if the patient has already undergone necrosectomy, the wounds have been appropriately debrided and conditioned by temporary wound care. If there are no complications, the islets adhere firmly to the wound bed no later than seven days after transplantation. Complete re-epithelialization of the gaps between the grafted islets is achieved within two weeks at expansion rates up to 1:3. Kreiss et al. reported a re-epithelialization time of five weeks at an expansion of 1:9 in combination with foreign skin.

Your attending physician is not yet familiar with the new, innovative SkinDot procedure? Please inform him/her about the possibility of treating your skin wound with the new SkinDot procedure. We will be happy to advise you and perform the SkinDot procedure on you (if indicated). We look forward to hearing from you!