What is the most likely cause of burning pain in the feet of a patient with poorly controlled diabetes?

Burning pain in the feet of a patient with poorly controlled diabetes is often associated with diabetic neuropathy, a common complication of the disease. The underlying mechanism involves nerve damage that results in abnormal sensations, including pain.

Persistent activation of voltage-gated sodium (Na+) channels plays a significant role in generating and sustaining the pain perceived in neuropathic conditions. When these channels are continuously activated, they lead to excessive depolarization of the affected neurons, which can result in the abnormal signaling responsible for the burning sensations. This sustained excitability of sensory neurons contributes to the neuropathic pain experienced by diabetic patients.

In this context, voltage-gated sodium channels become hyperactive or are inappropriately regulated, leading to the chronic pain symptoms that are characteristic of diabetic neuropathy. The burning pain is thus a result of the neurons' altered response and heightened sensitivity due to their excitatory state, making this the most plausible explanation for the symptoms described in the patient scenario.