A full-thickness skin graft (FTSG) is useful for covering small skin and soft tissue defects. In this paper, we suggest FTSG in consideration of the relaxed skin tension line (RSTL) concept for scar quality improvement since FTSG has disadvantages, including contour irregularities and mismatches of color and texture. We conducted a retrospective chart review of twenty-one patients with skin cancer on the face who underwent wide excision and FTSG by a single surgeon from October 2013 to July 2019. Twenty-one patients with skin cancer on the face were divided into RSTL-matched and RSTL-unmatched groups, and FTSG was performed. Each group was subjected to scar assessment three months after surgery. Observer assessment was performed by five independent observers using the observer component of the patient and observer scar assessment scale (POSAS) and Vancouver scar scale (VSS). Our results indicate that there were significant differences between the RSTL-matched and RSTL-unmatched groups in the VSS and POSAS components. In addition, the RSTL-matched group showed a natural appearance with surrounding tissue in the dynamic animation phase compared to the unmatched group. RSTL-matched FTSG can be an attractive option for face skin and soft tissue defect coverage. (An earlier version of this paper has been presented at the International Conference on PRS Korea 2020.)

The purpose of an animal wound model is to replicate the wound healing process of humans as accurately as possible. Although rodents are attractive candidates for animal wound models, the drawback is that their major wound healing occurs by contraction, which is fundamentally different from that seen in humans, where healing is achieved mainly by re-epithelialization and granulation tissue growth. There has been an attempt to overcome such drawbacks by applying an external splint on wounded mice. This model, however, has a few problems concerning the assimilating ability of external splints with the dynamic soft tissue movements and robustness issues. The authors hereby describe a new animal wound model using an internal splint made of nitinol, one of the shape memory alloys (SMAs). SMA wire was inserted intradermally around the full-thickness excisional wound to act as the internal splint, and its ability to impede wound contraction was analyzed. In experiment 1, three different sizes of SMAs (0.18 mm, 0.24 mm, and 0.30 mm diameters of thickness) were inserted as the internal splint and their ability to impede the wound contraction was compared. The most effective size of SMA as the internal splint was selected among them. In experiment 2, contraction of the wound with the selected size of SMA inserted as the internal splint was compared with that of the unsplinted wound. SMA as an internal splint effectively impeded wound contraction without affecting the re-epithelialization rate, thereby successfully mimicking the human wound healing mechanism. In this study, the authors introduce a novel animal wound model that replicates the human wound healing mechanism. This model is robust, reliable, and easily reproducible.

Shredder injuries have a poor prognosis and are a problematic type of hand trauma. The authors describe the successful management of two cases of shredder injuries, one involving a child and the other involving an adult. In the child, the authors performed loose skin sutures for closure in the initial surgery and adjusted the degree of intensity of the external compression daily. According to the degree of tissue swelling, the skin sutures were gradually tightened. In the adult, the authors used external compression rather than sutures and adjusted the degree of intensity every day. When treating a shredder injury, the most crucial task is balancing perfusion and tissue pressure to reduce edema while preserving viability, thereby healing and restoring the original function and shape of the injured body part. This paper suggests that external compression may be an important postoperative edema management method in patients with hand shredder injuries.