Between 1978 and 1982 154 femoral shaft fractures were treated in 145 adults in our department of general surgery and traumatology. 52 fractures were nailed intramedullary. We reserved the intramedullary nailing for ideal cases like the transverse and the short oblique fractures in the middle 3/5 of the shaft. 102 fractures were treated by a dynamic compression plate applying the AO principles correctly. Condylar plates were not included in this study. 88 patients with 95 FSF were followed up. In our prospective study a significant relationship was found between the types of fractures, the consolidation, the rehabilitation (including walking), the hospitalisation time and the full weight-bearing results. The prognosis for simple fractures was better than for comminuted fractures. Polytrauma patients showed a significantly slower limb rehabilitation, a longer hospitalisation and a worse clinical result than patients with isolated fractures. A significant relationship was shown between the mobility of the knee and the localisation of the fracture. In the beginning of our study we thought a delayed osteosynthesis (1-2 weeks) should lead to a faster consolidation but afterwards we didn't notice any significant difference with the early operation. General complications were restricted to one fat embolism. Important bone shortening (greater than or equal to 2 cm) was only measured 4 times (4.2%). Distinct rotation or angulation deformities were not observed. Bone infection occurred twice (2.1%). All but two of the 9 comminuted fractures healed within a year in spite of an initial delayed union.