Diabetes Foot Problems

Diabetes can cause a variety of foot problems. Daily foot care is an important part of diabetes care.

Diabetic foot problems are serious complications that may develop in people with diabetes, due to long-term effects of high blood sugar levels. Nerve damage often occurs in the feet and legs causing numbness and the loss of feeling, so that a patient may not notice a minor injury like a blister, cut, or scrape. Patients might not feel extreme hot or cold temperatures, or pain from shoes that don't fit properly. Poor blood sugar control also affects circulation by damaging blood vessels thus reducing blood flow to the feet. Additionally, nutrients can’t be delivered to the feet to help heal small wounds or to fight off infection. Overall wound healing is compromised in patients with diabetes.

Minor injuries can quickly turn into major issues for a person with diabetes. An unnoticed cut can become an open sore, known as a foot ulcer, that can be slow to heal and prone to infection due to poor circulation. In general, patients with diabetes may be immune compromised if an infection spreads deep into the tissue or bone, if poor circulation causes tissue death (gangrene), or if the infections spreads to the blood stream (sepsis). In the most severe cases, where infection or gangrene cannot be controlled, amputation (surgical removal) of a toe, foot, or part of the leg might become necessary to save the person's life.

Daily foot care is an important part of diabetes care. Blood sugar control, proper footwear, toenail maintenance, and seeing a healthcare provider for regular foot exams are important preventive steps. Seeking immediate care for any injury or infection is key to preventing a minor injury from developing into a major complication.

Two common complications of diabetes increase the risk of developing foot issues. These foot issues can affect patients with both type 1 and type 2 diabetes.

• Peripheral artery disease (PAD) reduces blood flow to tissues in the legs because fatty deposits build up inside arteries causing them to narrow. Diabetes is one of the risk factors for PAD along with high blood pressure and high cholesterol. Often it is the smallest arteries that are affected first. PAD can cause muscle pain with activity because not enough oxygen is being delivered to the muscles. It can also cause slow healing and cause tissue and nerve damage as nutrients are also not being delivered.
• Nerve damage (neuropathy) can be caused by persistently high blood sugar levels. The excess sugar directly damages nerves in the body by causing abnormal chemical reactions within the nerve cells altering their function in carrying sensory messages to the brain. This results in abnormal sensations like numbness, burning, and tingling. Poor blood supply because of PAD can also damage nerves. The tiny blood vessels that supply the nerves can clog reducing blood flow to them. The lack of oxygen and nutrients damages the nerve and ultimately will cause it to die. The longest nerves in the body (to the hands and feet) are usually affected first.

PAD and neuropathy work together to cause damage. Poor blood flow reduces healing while neuropathy makes the feet numb and unable to appreciate the signals of inflammation and injury.

Diabetic foot symptoms

Patients with diabetes are at high risk of developing diabetic foot symptoms, but many of these are non-specific and are often ignored. For that reason, routine visits with a healthcare provider to have a foot exam is an important part of diabetes care.

Symptoms can be progressive and initially may be considered “minor.” The patient may complain of changes to the skin and toenails like dryness, blisters, or sores. Small cuts or skin abrasions may not heal and can become infected. Depending upon the severity of the neuropathy, the patient may or may not feel any pain.

Abnormalities in the anatomy of the foot may occur with bunions, hammertoes, and callus formation. Unless recognized and treated this can progress to more severe symptoms.

Toenails may be discolored, thickened, and crumbling due to fungal infections. Fungal infections are often seen between the toes causing skin breakdown.

With PAD, pulses in the foot may be decreased or absent, hair on the foot may disappear, and the foot may feel cooler.

Neuropathy will involve the whole foot with discomfort and pain described as burning, numbness, or tingling.

More severe symptoms may arise including ulcers sometimes going deep into bone, and gangrene. These sores often weep with pus and are foul smelling. They can be associated with redness, increased swelling, redness streaking up the leg, fever, and chills. These infections can be life threatening causing sepsis and gangrene.

What is neuropathic osteoarthropathy (Charcot joint) in diabetic feet?

Diabetes is the most common cause of neuropathic osteoarthropathy or Charcot joint.

Neuropathy (neuro=nerve +pathy=abnormal) and loss of sensation is also accompanied by loss of proprioception, the loss of perception of body position and movement. Normally, the brain knows where the foot is positioned and makes automatic micro adjustments for balance and weight. But when proprioception is impaired, the foot joints sustain minor injuries leading to the ligaments that stabilize joints becoming lax or loose, and making the joints unstable.

Inflammation in the area abnormally heals these minor injuries laying down excess bone and cartilage that makes the joint stiff and immobile. The stiffness places stresses on the plantar facia and the tendons that support the foot which causes further damage. A vicious cycle is in place of damage causing faulty repair causing further damage.

There can be an acute attack of diabetic neuroarthropathy that presents with a hot, swollen painful foot as a result of a minor injury. If the diagnosis is made, aggressive treatment may prevent progression of the disease to the chronic phase.

With chronic neuroarthropathy, injuries may be recurrent and not appreciated. The chronic arthropathy (arthro=joint + pathy=abnormal) causes joints to collapse and major deformities are seen in the foot. Common deformities include the rocker bottom foot where the arch collapses and dislocation of the bones in the midfoot.

With the abnormal anatomy and architecture of the foot, bones that weren’t designed to bear weight are forced to do so. This leads to pressure sores and infection.

There are a variety of classifications to help guide the treatment of the diabetic foot. The Wagner system is an early classification tool that presumes all patients with diabetes will eventually develop foot issues. It ranges from Stage 0 which includes early stages of foot problems to Stage 5 for patients who have a necrotic (gangrene) dead foot.

• Stage 0: Skin intact but bony deformities lead to a foot at risk
• Stage 1: Superficial ulcer
• Stage 2: Deep ulcer (cellulitis)
• Stage 3: Osteomyelitis (bone infection) with ulceration or abscess
• Stage 4: Gangrenous patches; partial foot gangrene
• Stage 5: Gangrene of the entire foot

The Texas system updated the Wagner system and may help predict what care method may be needed. It uses a grade followed by a stage to help with the classification.

• Grade 0: Pre- or post-ulcerative (Stages A to D)
• Grade 1: Full-thickness ulcer not involving the tendon, capsule, or bone (Stages A to D)
• Grade 2: Tendon or capsular involvement without bone palpable (Stages A to D)
• Grade 3: Probes to bone (Stages A to D)

• Stage A: Noninfected
• Stage B: Infected
• Stage C: Ischemic (decreased blood supply)
• Stage D: Infected and ischemic

The healthcare provider and surgeon may use the staging system to guide developing a treatment plan for the individual patient. Ulcers and abscess may potentially heal with aggressive wound care, but for patients with bone infections or gangrene, operations may be needed to prevent the infection from worsening and spreading.

Diabetic foot treatment

Prevention is key to diabetic foot care and it begins when diabetes is first diagnosed. By maintaining good blood sugar control, the risk of PAD and neuropathy can be minimized, and the risk of developing diabetic foot disease decreased.

Treatment of the diabetic foot depends upon the symptoms. Skin and wound infection may need a team approach with specialists that routinely work with diabetic feet. Primary health providers, endocrinologists, podiatrists, surgeons, physical therapists, and others are members of the team that may be involved in care.

Special dressings and wraps can be used to protect skin as it heals. Antibiotics may be used to treat infections and prevent spread. Foot orthotics, splints, and braces may be used to help cushion the feet and help with gait.

Some infections may need surgical debridement, where infection is cut away so that healthy tissue can be allowed to flourish.

Gangrene describes tissue that has died. This is irreversible and requires surgery to remove the dead tissue.

Diabetes is a lifelong disease, as is diabetic foot disease. With constant attention to blood sugar control, the risk of foot disease decreases but does not go away. As the patient ages, if peripheral artery disease does not occur, and peripheral neuropathy is not an issue, ideally the severity of diabetic foot disease will be less.

Skin infections and ulcers often heal successfully depending upon their size, depth, and underlying health of the patient. Infections are common and 25% of hospital admissions for diabetic patients are for the care of foot issues.

More aggressive and severe infections, like osteomyelitis and gangrene have a less favorable outcome, and prognosis depends upon the underlying health of the patient.

The most severe complication of diabetic foot disease is uncontrolled infection. This can result in gangrene which is tissue that is dead, is not repairable, and needs to be surgically removed. If the gangrenous area expands and becomes infected, amputation may be required to stop the spread.

Foot infections can also spread through the blood stream to causes sepsis which is life threatening.

Diabetic foot care

In addition to keeping blood sugars under control, people with diabetes should check their feet daily for any signs of infection or injury. Routine appointments for foot examinations by a healthcare provider are important.

Minimizing the risk of peripheral artery disease is important and includes tobacco cessation and control of high blood pressure, cholesterol, and diabetes.

Suggestions for prevention include the following:

• Daily foot inspection. Ask a friend of family member for help if you cannot see your feet well.
• Toe nails need to be trimmed routinely and properly to prevent infection. A podiatrist can help demonstrate technique. A podiatrist may need to trim the toenails if you cannot do it safely.
• Feet need to be washed daily then dried and kept clean.
• Avoid hot or cold exposure for feet to prevent sunburns or blisters that can become infected.
• Do not go barefoot to prevent injuries, even minor scrapes.
• Shoes and socks need to fit well to prevent blisters, sores, or calluses. Orthotics or other shoe adjustments may be needed to get shoes to fit properly and avoid pressure sores.