This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Joint involved in rheumatoid ahritis are all EXCEPT: 
Select and explain. 
A. PIP, B. DIP, C. MCP, D. Cervical spine
B: DIP
Answer: B: DIP 
Explanation: DIP REF: Apley's 8th e p. 51-58 Commonly involved joints in RA: Wrist MCP PIP Elbow Knee Ankle MTP Less commonly involved joints: Upper cervical spine with atlanto axial subluxation Hip joint TM joint Subtalar and foot joints Joints not involved in RA: Lumbar spine DIP