Coverage for the vascular pedicle of a free fasciocutaneous flap using split thickness skin graft with auxiliary procedure to achieve a safe method with no impairment of vessels: a case series and literature review

Background: The vascular pedicle of a free flap is the most critical structure that determines its viability. Most of the times it is covered with local skin flaps raised from the recipient site or with part of the free flap itself. However, there are conditions in which the vascular pedicle can be covered with skin graft. The purpose of the present study is to describe our experience in the use of split-thickness skin grafts (STSG) as an auxiliary procedure for pedicle coverage. Methods: All patients who underwent microvascular fasciocutaneous free flap reconstruction at the Department of Plastic Surgery of China Medical University Hospital in Taichung from 1986 to 2021 were retrospectively evaluated. Patients who met all of the following criteria were eligible for the study: microvascular free flap reconstruction of any region of the body with a fasciocutaneous flap and cases where tension was detected during skin closure over the pedicle of the flap and STSG was applied as a cover. Results: There were 14 cases in this series treated from 1986 to 2021. Among them, 11 cases had no additional skin at the proximal end of the free flap, nor local flap at disposal in the recipient site to cover the vessels. In 3 other cases a vascular bridge flap was used for cross-leg flap transfer without possibility of tension free tubulization to protect the vessels. All reconstruction were successful. Conclusions: During microvascular transfer of free flaps, if no skin flap is available to cover the vascular pedicle, skin graft can be used to protect the vessels without compromising the circulation of the flap. Our results, in accordance with the literature, supports the safety of this technique when direct closure of the skin above and near the pedicle is not possible. Level of evidence: Level IV, Therapeutic.