Clinical application of keystone design perforator Island flap (KDPIF) in trunk defects: a retrospective study

Background The aim of this study was to evaluate the treatment outcomes of patients with trunk defects reconstructed by Keystone Design Perforator Island Flap (KDPIF). Method A total of 37 eligible cases with trunk defects were reconstructed by KDPIF from January 2017 to June 2020. Data were collected from electronic medical records, including aetiology, defect size and location, and type of KDPIF applied. Postoperative complications were recorded, and patient satisfaction was evaluated at the last clinical visit. Result There were 23 males and 14 females, and the average defect was 8.16 × 4.94 cm. Etiologies included decubitus ulcer (n = 12), oncologic resection (n = 11), infection (n = 9) and others (n = 5). Type III was applied in 19 cases, Type IIa in 13 cases, type IV in two cases and modified KDPIF in three cases. There were no major complications except delayed healing or wound dehiscence in three cases, which were managed by regular dressing or secondary surgical intervention. The average postoperative satisfaction score was 8.68 ± 1.13 points and all patients were satisfied with their cosmetic appearance and function at the last follow‐up. Conclusion Trunk defects can be successfully reconstructed by KDPIF, which results in satisfactory cosmetic and functional outcomes without major complications. The keystone design perforator island flap (KDPIF) was applied in the reconstruction of soft‐tissue defect in various regions of the body, clinical effectiveness of the KDPIF was described by use the acronym PACE (Pain free, Aesthetically acceptable, Lower complication and Economically effectiveness). As a local‐regional flap, KDPIF is completely relied on the soft tissue around the defect as the donor site and corresponding characteristics of soft tissue condition should be cautiously considered while designing and applying the KDPIF at different locations. It is not recommended to larger defect with less movability of surrounding soft tissue which is not enough to cover the defect. Another contraindication should be mention based on our experience is Morel–Lavallee injury of the donor site which could compromise the subcutaneous perforators and result in flap failure. Relative contraindications include local situation compromise the vascularity and laxity of the flap such as wounds that have been irradiated, or undergone significant undermining, or currently in an inflammatory status. Preoperative design of KDPIF should be individualized regarding pati