A painless foot wound is easy to overlook. For someone with diabetes, that can be a serious mistake.
Some people with diabetes lose sensation in their feet, making it difficult to notice cuts, blisters, or sores. Even when those wounds heal, they can return.
A 2023 JAMA review found that about 42% of diabetic foot ulcers recur within a year. An estimated 1.6 million Americans develop these ulcers annually.
Scientists have spent years trying to understand why these injuries are so hard to treat. One explanation involves the immune system, which sometimes struggles to move beyond inflammation and begin repairing damaged tissue.
A scientific review published in December 2025 examined that problem more closely. Its findings add to what doctors already know about the effects of nerve damage and poor circulation on diabetic wound healing.
What Scientists Found About Stubborn Wounds
The immune system may keep some diabetic wounds inflamed longer than it should.
On December 27, 2025, Yi Ru and fellow researchers published a review titled Immune cells in diabetic wound repair: the key to better wound management in Frontiers in Medicine. The paper examined earlier studies on how immune cells respond when a person with diabetes develops a wound.
Healing involves several steps. First, the body responds to an injury with inflammation, which helps protect the damaged area. That response must eventually shift so new tissue can form.
The researchers examined immune cells, including macrophages, neutrophils, and others, that participate in this process.
Macrophages were of particular interest. In some diabetic wounds, these cells remain in an inflammatory state instead of taking on functions that support repair.
The researchers wrote that “Immune cells play indispensable roles in orchestrating wound healing.”
Their review helps explain one reason wounds may remain open for long periods. However, it does not establish a new cure or prove that a particular immune treatment will work for patients.
When a Foot Injury Doesn’t Cause Pain
One of the difficulties with diabetic foot injuries is that people may not realize they have one.
The Centers for Disease Control and Prevention estimates that about half of people with diabetes have some form of nerve damage.
When that damage affects the feet, it can interfere with the sensations people normally rely on to recognize an injury. This condition is called diabetic neuropathy.
Someone might develop a blister from shoes rubbing against the skin. Another person might have a small cut but feel little or no discomfort.
Without pain drawing attention to the affected area, the injury may go unnoticed.
That is why the CDC advises people with diabetes to “Check your feet every day, even if they feel fine.”
Blood flow matters, too. Diabetes can affect circulation in the feet, slowing tissue repair and making infections harder to manage.
In other words, pain isn’t always a reliable way to judge whether a foot needs attention.
Related: A diabetes specialist reveals the breakfast foods she avoids and what she eats instead
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Why Healing Isn’t Always the End of the Problem
The risk of another ulcer remains substantial even after the original wound closes.
The 2023 JAMA review, led by David G. Armstrong, found that only about 30% to 40% of diabetic foot ulcers heal within 12 weeks.
Infection also remains a serious concern. The researchers estimated that 50% to 60% of diabetic foot ulcers become infected.
Among patients with moderate to severe diabetic foot infections, roughly 20% experience a lower extremity amputation. That percentage applies to this specific group, not everyone who develops a diabetic foot wound.
Recurrence is also possible.
The review estimated that approximately 65% of diabetic foot ulcers return within five years of healing.
Several problems can remain after the skin has closed. A person may still have damaged nerves, reduced blood flow, or areas of the foot exposed to repeated pressure.
Treating an ulcer therefore does not necessarily remove the circumstances that contributed to it.
This is why doctors emphasize continued foot care and prevention after a wound heals.
Could Future Treatments Make a Difference?
Researchers are looking beyond traditional wound care to understand whether controlling inflammation could improve healing.
The December 2025 review discusses approaches intended to influence immune cell activity and the signals involved in inflammation.
Some involve advanced wound dressings designed to deliver therapeutic substances directly to injured tissue. Others focus on changing how particular immune cells behave.
Timing is another area scientists are studying.
The immune system performs different tasks as a wound heals. A treatment aimed at inflammation may work differently depending on whether the body is responding to an injury or rebuilding damaged tissue.
Those ideas still need clinical evidence to determine which approaches offer meaningful patient benefits.
For now, established medical care remains central to treatment. According to the JAMA review, this includes removing damaged tissue, relieving pressure on the wound, treating infections, and addressing poor circulation.
After healing, regular foot exams, appropriate footwear, and medical follow-up can help reduce the risk of another injury.
The immune research adds useful detail to the science of wound repair, though it is only one part of a larger medical picture.
A wound may look like a skin problem, but its recovery depends on processes happening far beneath the surface. For people with diabetes, those processes can remain affected long after the visible injury disappears.
What does recovery really mean when a wound can close, but the conditions that contributed to it remain?
