  We present the first results on the analysis of the structures observed in
the jet of the quasar 0836+710. We obtain the ridge lines of the jet at
different epochs and several frequencies. We interpret the oscillatory
structures obtained as waves that can be attached to the growth of
instabilities. We explain how to derive information on the nature and origin of
these structures by fitting together the ridge lines at different epochs and
frequencies. Finally we show the predictive power of this approach: by
generating an artificial wave and applying the corresponding relativistic and
projection effects we show that apparent changes in the jet direction in the
inner regions of jets can be attached to the transversal motion of structures.
