INFLUENCE OF BONE-MARROW EMBOLIZATION ON THE CHOICE OF PROCEDURE IN THE STABILIZATION OF FEMUR FRACTURES

Because of an extended venous drainage system, especially in the supra condylar area, a pressure increase in the femoral cavity results in em bolization of the contents of the bone marrow cavity. Bone marrow embo lization alone is mostly not apparent clinically but together with cof actors it may result in severe pulmonary damage and occasionally even in death. Cofactors are volume deficit, shock, thoracic and polytrauma and preexisting pulmonary disease. In the field of traumatology a pre ssure increase in the femoral cavity regularly occurs during unavoidab le movement of femoral fragments in traction, during reduction, intrao peratively during intramedullary nailing, and in hip replacement. A he matoma acts as a hydraulic transmitter. Early osteosynthesis within 24 h avoids permanent intravasation of moderate amounts of the contents of the bone marrow cavity. Concerning intramedullary nailing, there ar e considerable differences between reamed and unreamed nailing. Reamin g always leads to high-pressure increases in the femoral cavity, resul ting in embolization. Therefore, reaming should not be performed if co factors of manifestation of pulmonary impairment are present. Unreamed nailing results in less intravasation, but is not entirely harmless, as considerable pressure increases occur in unreamed nailing as well. The gap between the nail and the entrance of the distal fragment is th e decisive parameter. Not just the smaller intravasation of bone marro w during unreamed nailing is important. After each reaming process, th e bone marrow cavity rapidly refills with blood, which is activated co ncerning coagulation and pressed into the circulation during the follo wing reaming process. Because of superior bone healing, interlocking n ailing is the treatment of choice in diaphysial femoral fractures. As far as the differential indications of reaming are concerned, the disc ussion is not yet closed. However, reaming should undoubtedly be restr icted to a few reaming processes. Before unreamed femoral nailing, the width of the bone marrow cavity must be examined exactly. If the widt h of the bone marrow cavity, the patient's condition and experience of the surgeon allow unreamed nailing, this procedure can be recommended . As the venous drainage system of the tibia is not important compared to the femur, the question of reaming or not in tibial fractures is n ot influenced by the danger of embolization, but by soft tissue damage and the stability of interlocking bolts. In patients with femoral fra ctures and cofactors for the manifestation of pulmonary impairment, th e choice of osteosynthesis type should take plating in its improved fo rm into consideration, as this preserves the vascularity of the fragme nts. In severely injured patients with a high injury severity score, t he primary operation time should be restricted to a minimum, and prima ry osteosynthesis should be performed with an external fixator. If a c hange to an intramedullary nail is performed early (between 1 and 2 we eks), it can be performed in one operation.