[Osteosynthesis of femur shaft fractures with the unreamed AO-femur nail. Surgical technique and initial clinical results standard lock fixation].

Nailing technique has changed in recent years in some important aspects which are not limited to the omitted reaming procedure. These changes concern patient positioning, reduction technique and determination of implant length and diameter. Approach and exposure techniques have been modified to new, less invasive procedures, in order to fulfill technical, functional and aesthetic requirements. Techniques and tricks have been developed for avoidance of fragment diastasis, axial and torsional malalignment and leg length differences. Finally, simple algorithms have been elaborated for the management of bilateral femoral shaft or ipsilateral tibial shaft fractures and the number and location of locking bolts. These algorithms, techniques and procedures were developed in a series of 108 femoral shafts, which were stabilized wit the AO unreamed femoral nail (UFN) in a prospective study between 1991 and 1994. Of these, 39 cases with a mean follow-up of 19.3 (range 8-40) months after trauma were reviewed. Fractures were classified according to Müller (1990): 6 type A, 21 type B and 12 type C. Closed soft tissue damage was classified according to our classification: C0/I, n = 14; CII, n = 15 (Tscherne 1982). Among 10 open fractures 4 were OI, 4OII, 1OIIIA and 1OIIIB (Gustilo 1976). The major complications were breakage of locking bolts (n = 2), one nail breakage after 9 weeks and one case of osteitis.