Strain analysis of complex three-dimensional nanobridges conducted via Raman spectroscopy requires careful experimentation and data analysis supported by simulations. A method combining micro-Raman spectroscopy with finite element analysis is presented, enabling a detailed understanding of strain-sensitive Raman data measured on Si nanobridges. Power-dependent measurements are required to account for the a priori unknown scattering efficiency related to size and geometry. The experimental data is used to assess the validity of previously published phonon deformation potentials.