CME Rheumatology 26: Rheumatological Cases Abstract. Special rheumatological cases are illustrated using various examples. On the one hand we present differential diagnoses and causes of a "Baker's cyst", on the other hand a case of involvement of the cervical spine in rheumatoid arthritis. Usually, the medical history and precise clinical examination will lead us in the right diagnostic direction. Further clarifications such as laboratory analyses or imaging procedures are used in a targeted manner, taking into account the clinic.