This study is a single-center, prospective, randomized controlled trial aimed at evaluating whether periosteal distraction combined with autologous split-thickness skin grafting can significantly improve graft survival rate at postoperative day 14 compared with skin grafting alone in patients with diabetic foot ulcers (Wagner grade 2-3 or post-amputation). A total of 104 eligible patients will be randomly assigned to either the experimental group (periosteal distraction + skin grafting, n=52) or the control group (skin grafting alone, n=52). Secondary outcomes include time to complete epithelialization, wound healing quality (BWAT score at 3 months), ulcer recurrence rate (at 6 months), foot function (AOFAS score), quality of life (DFS-SF score), and safety profile. This study aims to address the critical clinical bottleneck of poor graft survival in ischemic wound environments, providing a novel, minimally invasive, and synergistic treatment paradigm for diabetic foot ulcers.