Final answer:
Based on the symptoms and x-ray findings, osteoarthritis is the most likely diagnosis for the elderly woman with shoulder pain and articular calcification.
Step-by-step explanation:
The most likely diagnosis for an elderly woman presenting with pain, restricted movement in her shoulder, articular calcification, and destructive arthritis seen on initial x-ray is osteoarthritis. This condition is typically associated with aging and "wear and tear" of the articular cartilage. Osteoarthritis is characterized by the thinning of the articular cartilage, increasing pressure on the bones, and causing pain, inflammation, and joint stiffness. Risk factors for osteoarthritis include joint injury, physically demanding jobs, being overweight, and certain sports activities. Treatments for osteoarthritis may involve lifestyle adjustments, pain management, and in severe cases, joint replacement surgery.