Background: Rheumatoid arthritis (RA) is a chronic inflammatory disease that can lead to joint destruction. RA commonly associated with extra-articular manifestation. The most common musculoskeletal related extra-articular presentation is rheumatoid nodules. Rheumatoid nodule of foot and ankle is a rare presentation, reaching up to 1% of all cases. The diagnosis of the rheumatoid nodule is mainly clinical. Ultrasound and MRI are radiological studies that can support the diagnosis of the rheumatoid nodule. Treatment can be either conservative or surgical excision if symptomatic. Rheumatoid nodule usually affects the extensor aspect of the extremities and areas of frequent mechanical contact such as elbow and dorsum of the hand. We are presenting a case of an unusual location of the rheumatoid nodule on the anterior ankle that is reported previously in English literatures.Case Report: A 59-year-old lady known case of seropositive rheumatoid arthritis presented to the orthopedic clinic with a chief complaint of a mass on the anterior left ankle. MRI revealed heterogeneous soft tissue mass with a central cystic component. The patient was planned for surgical excision of the mass under anaesthesia.
Conclusion:The physician should be aware of unusual locations of presentation of rheumatoid nodules. Surgical indications for this mass include pain and restriction of joint movement.