‘Can a diabetic foot ulcer cause a bone infection?’

Diabetic foot ulcers, though seemingly minor, can indeed lead to severe complications in individuals with diabetes. These ulcers, caused by reduced sensation, poor blood circulation, and high blood sugar, have the potential to spread to the bone, a condition medically known as osteomyelitis. Dr. Rajiv Kovil, a Diabetes & Obesity Specialist at Zandra Healthcare, explains that bacteria can travel from the ulcer into deeper tissues, reaching the bone if left untreated.

This progression can lead to pus formation, tissue destruction, and swelling, which in turn can compromise blood supply and threaten the toe, foot, or limb, sometimes even jeopardizing the patient's life.

Several factors contribute to diabetes patients being more susceptible to serious infections. Diabetic neuropathy, which reduces sensation in the feet, can lead to unnoticed injuries like blisters or cuts. Additionally, poor circulation due to peripheral arterial disease (PAD) and high blood sugar levels further hinder healing and can interfere with the body's response to infection.

The symptoms of a deep, bone-invading infection might not always be dramatic, making them easy to overlook. Warning signs include increasing redness, warmth, swelling, pus or discharge, foul odor, rapid or deepening ulcers, tissue turning dark, or feeling bone through a sterile probe.

In the event that an ulcer reaches the bone, the infection is termed osteomyelitis. Symptoms may include redness spreading beyond the wound, a swollen, red toe, a deep ulcer, visible bone, or a bone that can be felt. Pain might increase as the infection worsens, but its absence doesn't necessarily indicate a mild condition. Fever, chills, marked weakness, or worsening blood glucose levels could signal a more severe infection.

Gangrene, rapidly spreading redness, deep abscesses, or signs of poor circulation are urgent concerns, as they indicate a potentially life-threatening situation.

Diagnosing bone infection involves assessing the ulcer's size, depth, and severity, checking for infection signs, and evaluating blood supply to the foot. A sterile probe test can help identify bone, but an X-ray might be inconclusive as early infections may not show up. In such cases, MRI or PET scans may be necessary. To identify the causative organism, a bone specimen obtained through sterile conditions is preferred over a superficial wound swab.

Treatment options vary, with antibiotics alone sometimes sufficient for selected cases without peripheral arterial disease or exposed bone. However, surgery may become crucial when dealing with dead or infected tissue, abscesses, gangrene, necrotizing infection, compartment syndrome, severe infection, or significant ischaemia. The primary aim of surgery is to remove the infection and salvage the affected limb.