Rheumatology is a subfield of internal medicine, but it also touches on the field of orthopedics. Internists or orthopedic specialists who have trained as rheumatologists, i.e. rheumatic orthopedists, concentrate primarily on the diagnosis and non-operative treatment of patients with inflammatory diseases. Mostly the locomotor system is affected, i.e. all types of joints, the spine, the bones, the tendons, the ligaments and the muscles. The diseases include rheumatoid arthritis - also called chronic polyarthritis - and psoriatic arthritis, an autoimmune inflammatory joint disease.
Rheumatologists have chosen to specialise in a wide range of tasks, from prevention and diagnosis to treatment and rehabilitation. The spectrum of diseases is quite diverse in this subarea of medicine as well: In addition to the diseases already mentioned, the spectrum includes ankylosing spondylitis, various forms of collagenosis - i.e. diseases of the connective tissue -, vasculitis and myositides. There are also hormonal and metabolic joint diseases, chronic bone diseases such as osteoporosis and chronic "soft tissue rheumatic" diseases such as fibromyalgia.
An essential difference between internal medicine and orthopedic rheumatology is that internal medicine is mainly concerned with the conservative treatment of rheumatic diseases - while orthopedic rheumatology mainly has a surgical approach.