Why Some Wounds Do Not Heal

What makes a wound chronic, the conditions that slow healing, warning signs of infection, and when a non-healing wound needs specialist wound care.

A clinician applying a bandage during wound care

Healing is normally an orderly process. Bleeding stops, inflammation clears the debris, new tissue fills the gap, and the repair gradually strengthens over the following weeks.

Most wounds move through those stages without anyone needing to think about it. Some stall. They sit in the inflammatory phase for weeks or months, never quite closing and never quite worsening enough to force the question.

A wound that has not made meaningful progress in four weeks, or has not healed in three months, is generally considered chronic. At that point the useful question is not which dressing to try next but what is blocking the process.

Why healing stalls

Chronic wounds usually have a reason, and often more than one. Identifying them is what separates wound care from wound dressing.

The blood supply is inadequate

Healing tissue needs oxygen and nutrients delivered by blood. Where arterial supply is reduced, repair slows regardless of how well the wound is dressed.

Venous disease causes the opposite problem. Blood pools in the lower leg, pressure builds in the tissues, and the skin breaks down. Venous leg ulcers are among the most common chronic wounds, and they respond to compression far more than to dressings.

An ultrasound probe used to assess circulation in a patient lower limb
Assessing circulation is one of the first steps in any non-healing lower limb wound, because it changes the entire treatment plan.

Diabetes is affecting sensation and repair

Diabetes interferes with healing in several directions at once. Elevated blood glucose impairs immune cell function, small vessel disease reduces perfusion, and peripheral neuropathy removes the pain that would normally make you notice an injury.

That last effect is the most dangerous. A blister or a stone in a shoe can go unnoticed for days, and by the time it is found the damage is well established.

A blood glucose meter and testing supplies
Glucose control is part of wound treatment, not a separate concern running alongside it.

Pressure is not being relieved

Sustained pressure cuts off local blood flow. On the heel, sacrum or the sole of a foot, unrelieved pressure will reopen a wound as fast as treatment closes it.

Offloading, whether by specialist footwear, a total contact cast, repositioning or pressure-redistributing surfaces, is frequently the single most important intervention for these wounds.

An orthopaedic walking boot used to take pressure off a foot
For a plantar foot ulcer, offloading the pressure often does more than any dressing on the market.

Infection or biofilm is present

Not every chronic wound is infected, but a persistent bacterial burden keeps the wound in an inflammatory state. Bacteria can form a biofilm, a protective layer that shields them from both antibiotics and the immune system.

Biofilm is one reason antibiotics alone frequently fail to resolve a chronic wound. Physical removal of dead tissue through debridement is usually needed alongside them, and this is a common point at which an infectious disease physician becomes involved.

Nutrition is insufficient

Building new tissue requires raw material. Protein, vitamin C, zinc and adequate calories all feed into repair, and deficiency is common in older adults and in anyone who has been unwell for a long stretch.

Fresh vegetables and protein ingredients on a kitchen table
Protein and micronutrient intake is a practical, modifiable factor in healing that is often overlooked.

Medications and other conditions are interfering

Long-term steroids, some immune-suppressing drugs and certain chemotherapy agents slow healing directly. Smoking constricts blood vessels and reduces tissue oxygen. Kidney disease, autoimmune conditions and untreated edema all contribute.

These factors rarely act alone. A diabetic foot ulcer with reduced arterial supply, unrelieved pressure and low protein intake has four problems, and treating one of them well will not close it. Untangling that combination is the reason chronic wounds are usually managed by more than one specialty at once, with input from the clinicians listed on the provider profiles page.

Common types of chronic wound

Most non-healing wounds fall into a handful of categories, and the category points directly at the treatment.

Chronic wound types and what usually drives them
TypeTypical locationMain driverCentral treatment
Venous leg ulcerLower leg, around the ankleVenous hypertension and edemaCompression therapy
Arterial ulcerToes, foot, bony prominencesReduced arterial blood supplyRestoring circulation
Diabetic foot ulcerSole of foot, toes, heelNeuropathy plus pressure and perfusion problemsOffloading, glucose control, infection management
Pressure injurySacrum, heels, hipsSustained unrelieved pressureRepositioning and support surfaces
Surgical wound dehiscenceAny operative siteInfection, tension or poor tissue qualityDebridement and infection control

Signs a wound has become infected

Some inflammation is normal early on. The features below suggest something more than ordinary healing.

  • Increasing pain rather than gradually decreasing pain
  • Redness spreading outward from the wound edge
  • Increased or newly discolored drainage, or a new odour
  • The wound enlarging or breaking down at the edges
  • Fever, chills, or feeling generally unwell
  • New swelling or warmth in the surrounding tissue

Spreading redness with fever, or a wound that becomes rapidly and severely painful, needs same-day assessment rather than a routine appointment.

What specialist wound care involves

A wound clinic assessment looks past the wound surface. Expect circulation testing, an assessment of sensation where relevant, measurement and photography for tracking, and often tissue sampling if infection is suspected.

Sterile dressings and gauze on a tray
Dressing selection follows the assessment rather than leading it, and changes as the wound moves through its stages.

Treatment then addresses the causes found rather than the wound alone. That may mean debridement, compression, offloading, targeted antimicrobial therapy, referral for vascular assessment, or coordination with the team managing your diabetes.

Dressings still matter, but they are chosen for the wound stage and the amount of drainage, and they are the last part of the plan rather than the first. Specialist wound care is largely about removing obstacles so normal healing can resume.

What helps at home

  • Keep blood glucose within your target range if you have diabetes
  • Wear the footwear or compression you have been prescribed, consistently
  • Inspect your feet daily if you have any loss of sensation
  • Eat enough protein, and treat appetite loss as something to raise with your clinician
  • Stop smoking if you smoke; the effect on tissue oxygen is direct and quick
  • Elevate the leg when resting if you have venous disease or swelling

Photograph the wound weekly in similar light. Progress over four weeks is far easier to judge from images than from memory, and it gives your clinician something concrete. Results and messages are available through the patient portal.

Frequently asked questions

When is a wound considered chronic?

Generally when it has not improved meaningfully in four weeks or has not healed in three months. The exact figure matters less than the trend: a wound that is not steadily getting smaller deserves a fresh assessment.

Why do antibiotics sometimes not help a non-healing wound?

Because the wound may not be infected, or because bacteria have formed a biofilm that antibiotics cannot penetrate well. Removing dead tissue and addressing the underlying cause is usually needed alongside any antimicrobial treatment.

Does a wound heal better covered or uncovered?

For most wounds, a moist covered environment supports healing better than leaving the wound open to air. The right dressing depends on how much the wound is draining and what stage it is at, which is why selection changes over time.

Can a chronic wound heal completely?

Many do, once the underlying cause is identified and addressed. Timelines vary widely, and wounds driven by circulation or pressure problems tend to take longest. Recurrence prevention matters as much as closure.

Which specialist should I see for a wound that will not heal?

It depends on the cause. Vascular, podiatric, surgical and infectious disease input are all used, often together. Your primary care physician can direct the first referral, and the practice contact page explains how to reach this practice.

You can read about the clinicians involved on the provider profiles page or review services on the practice overview.

Sources and further reading: NIDDK — Diabetes and foot problems.

This article is general health information, not medical advice, and it cannot account for your own history or medications. Discuss your situation with a qualified clinician before acting on anything you read here.