A 76-year-old man arrived in the hospital early morning complaining of low back pain and stiffness which he puts down to the previous days exertion. However, over the following two weeks, he felt progressively less well with poor appetite, more generalised muscle stiffness and pain throughout his shoulders, buttocks, and thighs. He was particularly troubled first thing in the morning and took a long time to dress. His sleep was disturbed with pain and he had difficulty in turning in bed.
He was starting to loose weight and his family was very concerned about him. What can be the probable diagnosis for this patient? *This case is by Docplexus editorial team for educative purpose only. Source : edinburgh rheumatology practice