Significant bony erosion of the distal 1st metatarsal, proximal 1st phalanx and base of the distal 1st phalanx with a rat-bitten appearance and overhanging edges. Surrounding soft tissue swelling medial to the erosion with increased density and calcific foci. Erosions involving midfoot and tarsometatarsal joints. Overall, appearances are in keeping with erosive tophaceous gout.