Ive been told lupus arthritis in my hip is causing leg and knee pain. with outer ankle swelling. can you explain why this would happen?

Soft tissue : lupus also result in soft tissue inflammation and will result in joint swelling and joint pain and area of ankle lateral "outside" has couple tendons and ligaments with ankle joint inflammation these structure will try to stabilize the joint and then will get inflamed because they over work on inflamed joint and resulting in inflamed structurs