Overview and new developments in intramedullary and cephalomedullary nailing

The primary objectives of osteosynthetic fracture stabilization are accurate fracture reduction, restoration of the anatomical axis and rotational alignment, and the provision of adequate biomechanical and biological conditions to support bone healing. In fractures of long tubular bones, these goals can be optimally achieved by intramedullary nailing, which provides long-segment internal splinting along the anatomical axis of the bone combined with locking screws to ensure axial and rotational stability. In addition, intramedullary nailing is a tissue-preserving technique, as nail insertion is performed remote from the fracture site, thereby minimizing soft tissue trauma within the fracture zone. The indications for intramedullary nailing include epiphyseal and diaphyseal fractures of long bones, selected metaphyseal fractures that can be stabilized using anatomically contoured nails, as well as reconstructive procedures such as the treatment of nonunions, corrective osteotomies, and arthrodeses of the lower extremity. A major advantage of intramedullary nailing is the high primary stability of the implant, which generally allows early functional rehabilitation. The resulting biomechanical benefits permit early full weight bearing and, in the treatment of fracture healing disorders, are associated with high rates of osseous union. Continuous improvements in implant design and instrumentation, together with the introduction of anatomically contoured reconstruction nails, are expected to further expand the indications and effectiveness of intramedullary nailing. This narrative review summarizes historical milestones, biomechanical principles, technical aspects, and recent implant developments in intramedullary nailing, with a particular focus on cephalomedullary nailing for unstable trochanteric and subtrochanteric femoral fractures. Special emphasis is placed on fracture reduction quality, implant selection, and screw positioning, as these factors remain the strongest determinants of fixation stability and clinical outcome.