[The flexible metallic intramedullary nail (Mechanical model and theoretical analysis)]. / Cuiul metalic suplu intermedular. (Model mecanic si analiza teoretica).

An ideal mechanical model is proposed for the system which includes the fractured femur and the flexible rod. Developing through calculus the consequences of hypotheses which define the model, the rigidity and the resistance of the system are evaluated. The theoretical considerations and the numerical results of the analysis indicate the superiority of the non-parallel assembly of the rods in the case of high diaphysary fractures.

[Flexible metallic intramedullary nail, an ideal osteosynthesis material for femoral fractions]. / Cuiul metalic suplu intramedular, material de osteosintezu ideal pentru fracturile femurului.

The authors have used modified Ender nails for the treatment of femural fractures. Nails of different sizes are used in different arrangements, depending on the site of the lesion. Thus, for fractures of the femural neck 3 metallic nails, with a diameter of 4 mm are used, introduced through the internal supra-condylian aspect in paralel arcs; two nails, 5 mm in diameter, are introduced in the same way for the correction of the fractures involving the trochanterian massif; for fractures sited under the trochanterian massif (diaphysis, supracondylian, and supra- and inter-condylian), 5 mm diameter nails are used, placed on the internal and external aspects of the condyl in metalic arcs. This type of intervention was demonstrated to be stable, rapid, non-haemorrhagic and with low risk of shock. Supported walking is started in the first week after surgery--in cases with fractures of the trochanterian massif and of the diaphysis--provided these are stable fractures, in the first month when unstable fractures occur at the same level, and after 3--4 months in cases of fractures of the cervical neck. The authors' experience in the treatment of 250 cases is presented.