Objective <p>Biological reconstruction of extensive meta-/diaphyseal bone defects using autologous fibular graft. Aim is stable defect bridging with preservation of the limb and restoration of function.</p> Indications <p>Intercalary bone defects caused by joint-preserving tumor resection of bone tumors, failed osteosyntheses with pseudarthrosis, chronic osteomyelitis after debridement, posttraumatic or congenital bone loss. Vascularized grafts are particularly indicated in cases of compromised soft tissue, previous radiotherapy, defects &gt; 10–12 cm, or anticipated delayed healing.</p> Contraindications <p>Severe peripheral arterial occlusive disease (donor or recipient site); active infections. Relative contraindications for vascularized grafts include short, biologically active defects with intact perfusion.</p> Surgical technique <p>Harvesting of the fibula as a&#xa0;vascularized or nonvascularized segment, adaptation to the defect, fixation using plates. In tumor resections possible combination with allografts or extracorporeally irradiated autografts (using Capanna technique)—especially in the lower leg to improve mechanical stability. Microsurgical vascular anastomoses are required for vascularized fibula.</p> Postoperative management <p>Early mobilization under unloading conditions, regular radiographic monitoring, and gradual weight-bearing based on consolidation. Physiotherapy to prevent joint stiffness; clinical monitoring of the donor site.</p> Results <p>Consolidation rates of 85–95% under appropriate fixation and soft tissue coverage. Fibula grafts show high biological integration, potential for hypertrophy under load, and long-term load capacity. Typical complications include nonunion, graft fracture, infection, vascular complications, and donor-site morbidity.</p>