Review Question - QID 218707

A 52-year-old male with a longstanding history of type II diabetes presents with ulceration along the left plantar forefoot (Figure A). He endorses pain in the area with some mild fevers overnight and denies ever having a foot ulceration. A cotton-tipped swab confirms the wound probes to an underlying bone. Transcutaneous oxygen pressure is measured at 48 mmHg. His labs are consistent with elevated inflammatory markers and an Hb A1C of 7.2%. A diagnostic MRI was obtained suggestive of sesamoid and first-ray osteomyelitis. He adamantly refuses any amputation procedures and undergoes an Achilles lengthening procedure, outpatient wound care, forefoot offloading bracing, and oral antibiotics. Which of the following risk factors is most predictive of treatment failure and eventual need for amputation?