Hi there I understand your concern... Operation is not only modality of treatment....The aim of treatment is to ease pain and stiffness; also, to keep the range of shoulder movement as good as possible...this can be achieved by pain killers and anti inflammatory agents...Physiotherapist they may try other pain-relieving techniques such as warm or cold temperature packs and transcutaneous electrical nerve stimulation (TENS) machines...regarding MRI its hard to suggest with out clinical examination.