Each moment you drive your vehicle, the lower control arm is under incessant duress. Since the bushing of the lower control arm is attached to the frame, it is even under more stress. The more mileage you accrue on your vehicle, the faster the lower control arm bushing wears down. Eventually when you hear small clunking noises, you know you have a damaged bushing which needs to be replaced. In this case, not only would we recommend bushings but also just the component of the arm that has failed.
Was it a bad pot hole or just component failure?