The purpose is to present our experiences with the conversion of external fixation to an intramedullary nail in the treatment of open fractures and fractures in polytraumatised patients. These are traumatological cases where primary use of an intramedullary nail is difficult or impossible.

References in the world literature to the two-stage treatment of the fractures of the tibial shaft are more than 2O years old and are considered as unsuccessful. However, later papers presented conversion as an advantageous procedure. A higher stability of the fracture and better comfort of the patient are acquired by the use of conversion.

From 1995 to 1999 in the Orthopedic Clinic Bulovka in Prague, Czech Republic, ten patients (8 male, 2 female) were treated by the method of conversion of external fixation to an intramedullary nail. The group of patients was composed of eight open fractures: one Gustillo-Anderson 1, two Gustillo-Anderson 2, three Gustillo-Anderson 3A, two Gustillo-Anderson 3B, one closed fracture Tscherne CIII, and one closed fracture Tscherne CII in a polytraumatised patient. Conversion was performed from 6 to 48 days after primary stabilisation by external fixation (mean 21.2 days). We currently use the UNI-fix clamp external fixator. Conversion by standard procedure is performed up to the 21st day to the 28th day after primary stabilisation. Injury of soft tissues and skin covering must be solved at the time of conversion.

Analysis of the results in the ten cases was made from three months to 4.5 years. All of the cases were subjectively classified as excellent or very good. There were no deep infections. In three cases there was prolonged secretion from the screw holes of the external fixator. For one patient, bone grafting into a fracture bone defect was necessary after six months. ROM of the knee and ankle joint was without reduction of function. When the period of follow-up was more than one year, all patients had perfect healing of the fractures.

This method gives very satisfactory therapeutic results with a minimum of complications, and covers the spectrum of the treatment of complicated fractures of the tibial shaft. However, the indications are very strict. If conversion is not able to be performed before the 21st to the 28th day after primary stabilisation, it is more advantageous to continue with treatment by external fixation because of the risk of deep infection. After the 28th day following primary stabilisation, conversion to an intramedullary nail is not indicated.