This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Rheumatoid Arthritis, Subject name: Orthopaedics
Which of the following Is not a feature of rheumatoid arthritis? 
Select and explain. 
A. Heberden nodes, B. Swan neck deformity, C. Ulnar deviation of lingers at metacarpopalyngeal joint, D. Symmetric reduction of joint space
A: Heberden nodes
Answer: A: Heberden nodes 
Explanation: Ans. is 'a' i.e., Heberden nodes o Heberden nodes is a feature of osteoarthritis and not rheumatoid arthritis.Important hand deformities of hand in RAo Boutonniere deformity : Flexion contracture of PIP joint and extension of DIP joint,o Swan neck deformity : Hyperextension of PIP joint and flexion at DIP joint,o Z-deformity : Radial deviation of wrist with ulnar deviation of fingers,o Hyperextension of 1st interphalangeal joint and flexion of MP joint.