[Callus distraction with the AO tubular fixator--principles, techniques and clinical examples].

Callus distraction in segmental transport for closure of traumatic or operative bone defects can be performed with the AO tubular fixator in various ways. Depending on the soft tissue situation and personal preference segmental shifting may either be achieved by tension wires running through the soft tissues (Augsburg model) or by percutaneous Schanz' screws (Basel model). Transportation along an intramedullary nail has certain advantages but also specific draw-backs. To be able to apply the optimal technique to a given situation it is necessary to be familiar with each of these methods. A hybrid system under development at this moment will facilitate anchorage in short epiphyseal segments. We are also going to have a clamp which can turn in itself for correction of axial malalignment.