Could an osseous density adjacent to rib seen on chest x-ray be a calcified nodule? combined with bone island on other rib - cause for monitoring?

Yes and discuss the : Matter with your doctor. A calcified nodule may appear to be near a rib on x-ray. Talk to your doctor to see if a ct scan is needed to get a better idea of the nature of the lesion.

osseous density : Is not the same as a calcified nodule. One is bone and one is not. A bone island is a denser part of the normal bone and of no significance.

A bone island: is benign and usually doesn't need follow up. Not sure what they mean by osseous density near rib, it implies it is related to bone, not necessarily a lung nodule.