Hello there, The navicular, cuboid and cuneiform are bones of your foot located at the base of your ankle. Cartilage is a kind of shock absorber located at the ends of bones. The help your bones glide over each other easily kind of how grease helps machine parts that are in frequent contact move smoothly. The report says that there is a loss of cartilage at the junction between the navicular and cuneiform which can be either due to excessive wear and tear as seen in runners or workers who stay for long periods on their feet. It may also be early signs of arthritis. Edema means a fluid buildup around the affected joint which can be the body s way of compensating for the cartilage loss. Hope this helps, Please feel free to address any further queries to me. I will gladly answer them,