The authors report 2 patients with a massive bony defect of the tibia due to chronic osteomyelitis. They reconstructed the defect using a free vascularized fibular osteocutaneous flap. Unfortunately, venous insufficiency was diagnosed 24 hours postoperatively. The previous anastomosed veins were promptly explored. The peroneal veins of the vascularized fibular bone graft were noted to be full of thrombi. After thrombectomy, the vessels became very fragile and broke down easily. It was impossible to achieve normal antegrade venous outflow from the previous vein of the donor graft; however, they found that distal runoff of the peroneal vein achieved a reverse venous outflow from the donor graft. The great saphenous vein was dissected and reanastomosed to achieve adequate venous drainage. This procedure may offer an alternative treatment for a flap with venous insufficiency.