The most common complications of lower 1/3 femoral stem fracture are two: 1. Injury to the blood vessels, which are the popliteal arteries and veins located in the popliteal fossa on the posterior side of the femur. If the artery is injured, a huge local hematoma will be formed after the artery ruptures, and the hematoma will compress the vein causing obstruction of venous return, and the swelling of the limb will be so severe that the distal limb will be ischemic, bruised, purple, white, and even necrotic. If the vein is compressed, the venous return will be impaired and the distal limb will be highly swollen.2. Injury to the nerve, the sciatic nerve passes through the posterior side of the lower 1/3 of the femur, if the distal end of the fracture is displaced backwards, it may stab the sciatic nerve and cause damage to the sciatic nerve, resulting in paralysis of the lower limb, foot drop and other symptoms.