Posted 1/6/2015 4:30 AM (GMT 0)
well, it could be a pleural rub, sticky secretion in airway, mediastinitis, pleurisy as mentioned, or a noisy joint articulation in the chostocondrals, sternum, upper torso or neck, etc etc...
Not requiring an x-ray necessarily, but careful chest eval by stethoscope, percussion, and palpation will inform the provider's call on whether imaging is needed or not.