Intramedullary osteosynthesis in the treatment of lower extremity fractures.

AO Principles are described today as follows: * appropriate reduction * appropriate stabilization * preservation of vascularity * painless early mobilization These requirements can all be met by intramedullary osteosynthesis for suitable indications. The modern generation of nails is highly user-friendly and application of the systems is very safe. Outcome predictions favor reamed locked nailing for suitable fractures, whereby reaming should be moderate. The need to activate the dynamization option should be evaluated six to eight weeks postoperatively.