[Reamed intramedullary nailing]

The stabilization of long bone fractures through reaming the medullary cavity and insertion of an intramedullary nail, with or without locking bolts, was a standard procedure in fracture treatment for a long time. With the development of nails, which can be applied without reaming, the procedure lost importance. This publication presents the mechanical principles and impact of reaming on the bone. It describes how the pressure of the drill head and drill wave leads to a compression of medullary contents into the cortical vascular system. With the development of new drilling devices the direct effects of pressurization can be minimized and then become similar to those of unreamed intramedullary nailing. Lowering the pressure during reaming also prevents the formation of mixed thrombosis on the base of a nucleus of the bone marrow in the venous circulatory system and the danger of a pulmonary embolism. The majority of experimental research shows slightly faster fracture healing after reamed nailing. In the few randomized clinical studies presented, exclusively coming from Canada, accelerated fracture healing has also been confirmed. Aside from this it was also shown that there were fewer cases of non-unions and implant failures and less need for secondary surgeries when reamed nailing was used. Despite the difficulty in rating the clinical trials presented, due to the high number of participating clinics, the impression remains that in the course of fracture healing intramedullary reamed nailing has some advantages in comparison to unreamed nailing. An obvious advantage is that earlier and sometimes immediate weight-bearing can be tolerated. Today nevertheless unreamed nailing is favoured especially in German-speaking countries. This is maybe due to the necessary classic procedure of planning, positioning on the fracture table and reaming in steps, which make the operation slightly more complex, requiring a certain amount of armamentarium and technical understanding. In any case reamed intramedullary nailing offers an alternative procedure for many indications; to treat a hypertrophic non-union of the shaft of the long bones it remains the method of first choice.