A 60-year-old man with 20 years of type 2 diabetes presents with painless swelling, erythema, and warmth of the right foot over 3 weeks. He has absent protective sensation on 10 g monofilament testing, absent vibration sense, and ankle jerks. Radiographs show midfoot collapse with Lisfranc joint dislocations, bony fragmentation, and periarticular osteopenia. The structure marked **A** in the diagram demonstrates the characteristic rocker-bottom deformity with midfoot collapse. Which of the following pathophysiologic mechanisms is MOST responsible for the progressive joint destruction seen in this condition?