OBJECTIVE Restoration of axis, length, and rotation of the lower leg. Sufficient primary stability of the osteosynthesis for early functional aftercare. Maintaining mobility of knee joint. Bone healing in closed and open fractures. METHODS Closed and open isolated proximal tibia and lower leg fractures (AO 42). Extraarticular fractures of the proximal tibia (AO 41 A2/A3). Intraarticular fractures of the proximal tibia (AO 41 C1/C2) in combination with other implants. Segmental tibia fractures (AO 42 C1/C2) with short proximal fragment. Comminuted tibia shaft fractures (AO 42 C3) with short proximal fragment. METHODS Very poor general condition (e.g., bedridden). Flexion of knee less than 90°. Infection in the nail's and bolt's insertion area. Infection of the tibia intramedullary canal. Complex fractures of the tibia plateau (AO 41 C3). Open physis. METHODS Closed reduction of the fracture. If necessary, use of reduction clamps through additional stab incisions or open surgical procedures. In some cases, additional osteosynthesis procedures are necessary (e.g., compression screws). Positioning of the patient on a radiolucent table or a traction table. Opening of the proximal tibia in line with the medullary canal. Cannulated or noncannulated insertion of the nail with or without reaming of the medullary canal. Control of axis, length, and rotation of the lower leg. Triple proximal interlocking in three different planes with the targeting device. Double distal interlocking. METHODS Immediate mobilization of the knee joint. Depending on the type of fracture, mobilization with 20 kg partial weight bearing or pain-dependent full weight bearing with crutches. X-ray controls after 3, 6, and 12 weeks and increase of weight bearing depending on the fracture status. RESULTS In a prospective multicenter study on the stabilization of tibia fractures with the Expert Tibial Nail, 22 patients with proximal third tibia fractures were documented. Seventeen patients could be reviewed clinically and radiologically after 1 year. A non-union was registered in 1 patient (5.9%), a malalignment in any plane above 5° in 3 fractures (17.6%).