Covering defects by free-tissue transfers enable surgeons to reconstruct or salvage the lower extremity injured or amputated in high-energy traumas which result in extensive damage to soft tissue, bone, tendons, vessels and nerve. The timing of the reconstruction using flap techniques is extremely important. It can be divided into three categories: "primary free flap closure" (12 to 24 hours), "delayed primary free flap closure" (2 to 7 days), and "secondary free flap closure" (after 7 days). Our treatment of choice in an isolated complex injury of a lower extremity with a soft tissue defect is "primary free flap closure" providing improved funcional and aesthetic results, and psychologically benefit through lowered morbidity of the patient.