A 45-year-old male with a history of polyuria presents with following condition, what is the most possible diagnosis?

Diabetic foot: Ulceration of the calcaneus and bones of the forefoot, especially the great toe and first metatarsal head, is common, leading to deep extension and osteomyelitis. Presence of granulation and fibrosing border indicated aerial ulcer which the above picture it signifies diabetic foot. Ref - Bailey and love 27e p532 p953