What is Diabetic Foot?
Diabetic foot is one of the most serious and disabling long-term complications of diabetes mellitus. It represents a significant global health burden, affecting millions of patients worldwide and standing as one of the leading causes of non-traumatic lower limb amputation.
The condition results primarily from two major pathological mechanisms that frequently coexist in diabetic patients:
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Diabetic neuropathy: a progressive deterioration of nerve function, predominantly affecting the lower limbs. It manifests with tingling, leg cramps, gait disturbances, and perceptual alterations, most critically the inability to perceive pain, heat, or cold.
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Diabetic arteriopathy: a pathological condition attributable to disorders in arterial blood circulation, resulting in chronically poor blood flow to the feet and lower extremities.
The neurological damage caused by diabetic neuropathy is responsible for a profound alteration in the patient’s sensory capabilities. As a result, individuals may fail to notice the presence of wounds, burns, frostbite, blisters, or pressure injuries, since the ability to perceive stimuli at the level of the foot and respond to pain is severely compromised.
Furthermore, because neuropathy is frequently accompanied by circulatory impairment of the lower limbs (arteriopathy or vascular lesions), even a minor wound can become complicated and cause very serious harm, including the formation of bleeding ulcers. Over time, these may evolve into gangrene (massive necrosis and tissue decomposition that, in most cases, requires surgical amputation).
It is therefore of paramount importance for patients living with diabetes mellitus to maintain strict glycemic control, adhere to scheduled medical visits, and follow prescribed therapies. If underestimated or inadequately managed, diabetes can severely compromise a patient’s quality of life and ultimately their survival.
Causes
At the root of diabetic foot is diabetes mellitus, a chronic metabolic disease caused by a combination of hereditary and environmental factors. It is characterized by persistently elevated blood glucose levels resulting from an abnormal amount or function of insulin, the hypoglycemic hormone produced by the pancreas that enables glucose to enter cells and be used as an energy source.
Although the complications of diabetes can affect virtually every organ system in the body, including the heart, kidneys, eyes, nervous system, and circulatory system, the ulcerative lesions that develop in diabetic foot are among the most feared. This is due to their potential to lead to limb amputation and, in some cases, death.
Key epidemiological facts about diabetic foot include:
- 40–70% of all lower limb amputations are related to diabetes mellitus
- Diabetic foot is frequently a visible manifestation of widespread cardiovascular disease, which may involve not only the circulation of the lower extremities but also the coronary arteries (the vessels supplying the heart). This significantly increases the risk of ischemic heart disease.
Diabetes reduces the amount of blood able to reach the feet, impairing the delivery of oxygen and essential nutrients. This impaired circulation makes it increasingly difficult for wounds and infections to heal. In the worst-case scenario, lesions fail to heal and instead progress toward gangrene, the death and decomposition of tissue.
Simultaneously, diabetic neuropathy compounds the problem by reducing sensory awareness in the feet, causing patients to lose the ability to feel the development of blisters, abrasions, burns, or foreign body injuries.
Neuropathy and impaired circulation together create a dangerous downward spiral in which wounds and ulcerations become progressively more difficult, and sometimes impossible, to treat.
Symptoms
The early warning signs of diabetic foot may be subtle and easily overlooked, particularly given the sensory deficits that often accompany the condition. Initial symptoms can include:
- Increased foot temperature
- Altered sensitivity: loss of response to thermal (hot/cold), tactile, and pain stimuli in the lower limbs
- Blisters, cuts, scratches, or ulcerations (which the patient may not feel)
- Tingling or burning sensations (often worse at night, disrupting sleep)
- Cold, pale skin (an important warning sign of compromised circulation)
- “Pins and needles” sensation in the feet and legs
Over time, and particularly when significant nerve damage has occurred, symptoms may progress to include:
- Development of open ulcers
- Abnormal gait and walking difficulties
- Infections that may penetrate the deep layers of skin and eventually reach bone (osteomyelitis)
Although less common, neurological damage caused by diabetes can also result in structural deformities. One such condition is Charcot foot (Charcot neuroarthropathy), a serious and progressive disorder that may initially present with:
- Redness and warmth
- Marked swelling
In more advanced stages, the bones of the foot may shift or fracture, leading to permanent structural deformities that dramatically alter the biomechanics of walking and further increase ulceration risk.
Important: If even a single one of these symptoms is observed, it is essential to consult a healthcare provider promptly. Early detection significantly improves outcomes.
Diagnosis
Since diabetic foot is a neuropathic and vascular complication of diabetes mellitus, proper management and monitoring of the diabetic patient are fundamental to preventing its onset. A comprehensive diagnostic evaluation typically includes:
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Medical history and physical examination: After collecting a thorough clinical history, the physician will carefully assess the patient’s vital signs (body temperature, heart rate, blood pressure, and respiratory rate) and perform tests to assess sensory thresholds in the hands and feet, as well as lower limb circulation.
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Blood tests: These allow evaluation of potential infection, hematological disorders, and standard diabetic parameters such as fasting blood glucose and glycated hemoglobin (HbA1c).
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X-ray: Indicated when bone damage or foreign bodies within soft tissues are suspected (e.g., gas within an ulcer in the context of active gas gangrene).
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Ultrasound / Doppler echocardiography: Eco-Doppler studies may be requested to assess the status of blood vessels and peripheral arterial flow.
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Angiography: Performed by infusing contrast dye into the bloodstream, this imaging technique provides a detailed representation of the body’s vascular anatomy, guiding potential revascularization procedures.
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Microbiological cultures: In the presence of infected wounds or ulcers, wound swabs and tissue cultures are essential to identify the causative pathogen and guide targeted antibiotic therapy.
Treatment
Thanks to the adoption of multidisciplinary team approaches, significant advances have been made in recent years. Amputation rates have been reduced by 49–85% in centers employing coordinated diabetic foot care programs.
Treatment of diabetic foot is individualized and may include:
- Personalized wound care and therapeutic planning aimed at ensuring revascularization of the affected limb
- Debridement (removal of non-viable, necrotic tissue) followed by dressing with sterile bandages and gauze
- Offloading devices (orthotic supports and pressure-relief footwear) to prevent further mechanical trauma to vulnerable areas
- Targeted antibiotic therapy against the identified pathogen in cases of confirmed infection
- Pain management using analgesics and anti-inflammatory medications (under medical supervision)
- Hyperbaric oxygen therapy (HBOT): Effective in inhibiting the proliferation of anaerobic bacteria and promoting wound healing by delivering high-concentration oxygen to ischemic tissues
- Regenerative and reconstructive treatments: Including skin grafts, bioengineered tissue substitutes, and advanced wound care technologies
- Vascular surgery or endovascular procedures: In cases of significant peripheral arterial disease, surgical or percutaneous revascularization may be necessary to restore adequate blood flow
The involvement of a multidisciplinary team, typically including a diabetologist, vascular surgeon, orthopedic surgeon, infectious disease specialist, wound care nurse, and podiatrist, is considered the gold standard of care.
Prevention
Regular medical check-ups are essential to assess the risk of this complication in diabetic patients and to prevent the condition from worsening. A comprehensive diabetic foot prevention program includes:
1. Identification of the At-Risk Foot
A thorough evaluation by a diabetologist is fundamental. Based on the patient’s risk profile, the specialist will schedule follow-up appointments at appropriate intervals, such as monthly, quarterly, or annually, according to the level of risk identified.
2. Periodic Foot Inspection and Examination
This involves assessing:
- Hygiene practices and appropriate footwear use
- The presence of deformities
- Existing or previous wounds, ulcerations, or skin lesions
3. Patient, Family, and Healthcare Staff Education
Patient education is one of the most powerful tools in preventing diabetic foot complications. Patients should be instructed to:
- Perform a daily self-examination of both feet
- Monitor for pain, tingling, sensitivity changes, discoloration, or skin breakdown
- Seek prompt medical attention at a specialized diabetic foot center if any abnormality is detected
4. Appropriate Footwear
Footwear plays a critical role in prevention. Shoes should:
- Be neither too tight nor too loose
- Have no irregular edges, seams, or internal protrusions
- Be adapted to the patient’s specific foot biomechanics and any existing deformity
- Ideally be custom-made or orthopedically certified for high-risk patients
5. Treatment of Pre-Ulcerative Lesions
Proactive management of minor foot problems can prevent progression to serious ulceration. This includes:
- Removal of calluses by a qualified podiatrist.
- Protection or drainage of blisters under appropriate conditions.
- Treatment of ingrown toenails or thickened nails: extreme care must be taken when cutting nails. Sensory deficits combined with microcirculatory impairment can result in small bleeding lesions that, if neglected, may become highly dangerous.
- Treatment of fungal infections (tinea pedis, onychomycosis).
Daily foot care routine for diabetic patients:
- Wash feet daily with lukewarm (not hot) water and mild soap
- Dry thoroughly, especially between the toes
- Apply a moisturizing cream to prevent skin cracking (avoiding the spaces between toes)
- Never walk barefoot, even indoors
- Check inside shoes for foreign objects before wearing
Sources and Bibliography
- JAMD – Journal of AMD
- Understanding Diabetic Foot – National Center for Biotechnology Information (NCBI/PMC)
- Armstrong DG, Boulton AJM, Bus SA. Diabetic Foot Ulcers and Their Recurrence. N Engl J Med. 2017;376(24):2367–2375.
- International Working Group on the Diabetic Foot (IWGDF). IWGDF Guidelines on the Prevention and Management of Diabetic Foot Disease. 2023. Available at: https://iwgdfguidelines.org
- Boulton AJM, et al. Comprehensive Foot Examination and Risk Assessment. Diabetes Care. 2008;31(8):1679–1685.
