sway arm control??

i have a 88 prelude, this morning i woke up started driving and my rear drivers side tire started shaking and wobbling and it was fish tailing,
i got out of the car and i could phisically shake the wheel back and forth
i called my friend he said the bushings in my rear sway control arm has deteriorated and needs to be replaced, is this the problem?, and is that the only thing i need to do to fix this???