Comparable clinical and radiographical outcomes between second and third generation of gamma nails.

The aim of the study is to compare the overall complication rate and in particular lag screw cut-out between the Trochanteric Gamma Nail and the Gamma 3 Nail. A total of 294 implants (Trochanteric Gamma Nail= 132 and Gamma 3 Nail=163) in 291 patients were analysed. All clinical data was obtained from the patients medical records. Subsequently radiographs were evaluated for fracture type according to the AO classification and lag screw position by determining the tip-apex distance, the Parker's ratio and the neck- shaft-angle. No significant differences in complication rates were found. The Parker's ratio was associated with lag screw cut-out : patients with medial cut-out had more a posteriorly placement (n=9, 3.1%), while patients with cranial cut-out had a more cranial placement of the lag screw (n=10, 3.4%). The tip-apex-distance and neck-shaft-angle were not associated with cut-out. The complication rate of the Gamma 3 Nail does not differ from the Trochanteric Gamma Nail. A lag screw positioning central or slightly inferior on the anteroposterior view and central on the lateral view is recommended.