Pain is the first and most common symptom of thumb arthritis. Pain can occur at the base of your thumb when you grip, grasp or pinch an object, or use your thumb to apply force. Other signs and symptoms might include: 
Swelling, stiffness and tenderness at the base of your thumb
Decreased strength when pinching or grasping objects
Decreased range of motion
Enlarged or bony appearance of the joint at the base of your thumb
