A proper ankle exam would involve an arthrogram, in which they stick a needle in the joint, remove joint fluid & replace it with contrast agent. Not a pleasant thought. Osteoarthrosis is the more common term for cartilage loss while osteoarthritis is the term for inflammation. Long considered wear & tear diseases, they're slowly becoming genetic. They happen in knees & hips, but rarely in ankles so it might still be a ligament or a 1 off cartilage tear. Lions never pound on their ankles that hard though. Lions aren't smashing their ankles & stopping with each step. They're conserving as much momentum as possible by pushing back. In a long effort, they're more speed walking than running. It might be worth capturing the real accelerations felt by the paw by strapping on an accelerometer, then progressively going from walking to maximum speed. ------------------------------------------------------------------------------...