Cellulitis. Rule out "osteo" versus necrotizing cellulitis. The subcutaneous fat of the ankle is replaced with intermediate density compatible with edema that propagates through the subcutaneous fat along the dorsum of the foot. There is associated skin thickening, as well as blistering along the lateral aspect of the ankle and dorsal aspect of the forefoot. The musculature of the forefoot also appears edematous. Furthermore, there are multiple foci of gas density within the soft tissues surrounding the head of the second metatarsal and extending dorsal to the head of the first metatarsophalangeal joint and the proximal phalanx of the second toe, in close association with the extensor tendons of the 1st and 2nd rays. There is also a poorly defined collection of low density within the plantar musculature of the foot deep to the flexor tendons of the second ray beneath the second metatarsal diaphysis which could represent a developing abscess or septic tenosynovitis; small foci of gas are seen within this collection. I see no site of skin ulceration on this study to suggest a source for this gas, and therefore, I cannot exclude the possibility of a necrotizing infection. I see no specific imaging features of osteomyelitis. Osteoarthritis affects the first metatarsophalangeal joint and midfoot articulations.
Soft tissue infection of the foot as described above.