Diabetic Foot Care

Foot and lower leg ulcers are one of the many problems caused by poorly controlled diabetes. Ulcers that do not heal can lead to amputations of toes, parts of the foot, or the lower leg. Diabetes damages blood vessels throughout the body.

Calluses, blisters, cuts, burns, and ingrown toenails can all lead to diabetic foot ulcers. A patient may not be aware of these minor injuries due to peripheral neuropathy, so ulcers may develop and enlarge before they are noticed. Daily foot inspection is an important part of diabetes management and can help prevent foot ulcers.

Here is an excerpt from a video interview of Dr M Raja, Consultant General and Laparoscopic Surgeon at OMNI Hospitals, Visakhapatnam on Diabetic Foot Care – causes, prevention and treatment.

Q. What are diabetic ulcers?

A. Diabetic foot ulcers form as a result of a loss of peripheral sensation and are typically seen in individuals with diabetes. Local paresthesias, or lack of sensation, over pressure points on the foot leads to extended microtrauma, breakdown of overlying tissue, and eventual ulceration.

Q. What are the symptoms of diabetic ulcers?

A. The appearance of diabetic foot ulcers will vary based on the location and patient’s circulation and can appear as calloused blisters to open sores that are reddish to brown/black. 

The wound margins are usually undermined or macerated, and the surrounding skin will often be calloused, with the depth of the wound depending on the amount of trauma the skin has been subjected to.

Q. What are the causes of diabetic ulcers?

A. Both type 1 and type 2 diabetes cause damage to blood vessels and peripheral nerves that can result in problems in the legs and feet. 

Two main conditions, Peripheral artery disease (PAD) and Peripheral Neuropathy are responsible for the increased risk of foot problems in people with diabetes.

– In people suffering from Peripheral Artery Disease, there is a decreased delivery of oxygen to the lower legs and feet. In severe cases, the lack of oxygen delivery to tissues results in ulcers and even gangrene (tissue death)

– In people suffering from Peripheral Neuropathy, there is damage to the peripheral nerves directly as a result of diabetes. Peripheral Neuropathy decreases sensation in the nerves of the legs and feet, making it difficult to perceive injuries due to lack of feeling. It can also cause the muscles of the feet to work improperly, leading to misalignment of the foot that can put pressure on certain areas of the foot

Q. What are the three main complications that arise due to lack of sensitivity?

A. Three complications arise from lack of sensitivity:

– Constant pressure for several hours leads to local ischemic necrosis (e.g., in the absence of pain when wearing tight footwear).

– High pressure over a short period of time leads to immediate injuries. Objects with a small surface such as nails, needles, and sharp stones etc. cause direct mechanical damage.

– Repetitive moderate pressure causes inflammatory autolysis of tissue. Ongoing pressure on already inflamed or structurally affected tissue additionally promotes the development of ulcerations. Furthermore, gangrene develops from burns with hot items such as hot-water bottles and heating blankets, excessive sunbathing, acid burn (“corn plaster”) as well as improper use of disinfection products.

Q. How is a diabetic foot ulcer physically examined?

A. A physical examination includes inspection of the stature, gait, foot (the integrity of skin, muscular condition and bone structure, deformities of the feet such as claw toe, hallux valgus, hollow foot, skew foot and flat foot) and footwear. Prominent features are dry and fissured skin with hyperkeratosis as a sign of polyneuropathy.

Q. What are the stages involved in diabetic foot ulcers?

A. There are two main systems to classify the stages involved in diabetic foot ulcers.

The Wagner diabetic foot ulcer classification system assesses ulcer depth and the presence of osteomyelitis or gangrene by using the following grades:

Grade 0 – intact Skin

Grade 1 – superficial ulcer of the skin or subcutaneous tissue

Grade 2 – ulcers extend into tendon, bone, or capsule

Grade 3 – deep ulcer with osteomyelitis, or abscess

Grade 4 – partial foot gangrene

Grade 5 – whole foot gangrene

The University of Texas system grades diabetic foot ulcers by the depth and then stages them by the presence or absence of infection and ischemia:

Grade 0 – pre or post ulcerative site that has healed

Grade 1 – superficial wound not involving the tendon, capsule, or bone

Grade 2 – wound penetrating to tendon or capsule

Grade 3 – wound penetrating bone or joint

Within each wound grade there are four stages:

Stage A – clean wounds

Stage B – non-ischemic infected wounds

Stage C – ischemic non infected wounds

Stage D – ischemic infected wounds

Regardless of which classification system is used, it is essential that the system is used consistently across the healthcare team and be recorded appropriately in the patient’s records.

Q. What are the treatment options available for diabetic foot ulcers?

A. The two main treatment options are,

Conservation therapy: 

The main objective is to stop progression to prevent further deformities of the feet resulting in ulcers. Disease activity is measured by the degree of swelling, erythema and especially skin temperature. The difference in temperature should be at least 2 °C compared to the unaffected side. The basic therapeutic principle is a quick and consistent pressure relief by means of temporary immobilisation, wearing of a protective cast (Total Contact Cast) or orthosis until the acute phase has subsided. Patience is needed from both the patient and diabetes team as this process can take months.

Surgical therapy:

It becomes necessary in cases whereby plantigrade foot position and resilience of the foot cannot be gained by conservative approaches. Once the healing of ulcers is fully complete, local exostoses should undergo resection. Resection of exostoses by elliptical circumcision of ulcerations may be an alternative for plantar ulcers and exostoses. For serious Charcot deformities of the feet and instabilities, arthrodesis measures should be employed. The most important objective of treatment is then the resilience of foot, plantigrade foot position and adequate shoe or orthosis provision.

Q. What are other complications that can arise due to diabetic foot ulcers?

A. Complications like renal disorders, arthritis, weakness, ingrown toenails, athlete’s foot and corns can arise due to diabetic foot ulcers.

Q. Is it recommended to wear sports shoes continuously for 10 hours?

A. It is usually recommended to not wear any shoe for more than 4 hours, although in a healthy condition, it doesn’t matter much.

Q. Which specialist should be consulted for diabetic foot ulcers?

A. Diabetic foot ulcers are generally taken care of by multiple specialists that include a physician, general surgeon, plastic surgeon, orthopaedic surgeon and more.

Q. What is the pathogenesis of diabetic foot ulcers?

A. Most cross-sectional studies have revealed that chronic ulcerations are most often preceded by minor trauma.

About 50% of patients with diabetes mellitus develop symptomatic peripheral neuropathy within 25 years of disease onset. Patient age, disease duration and quality of diabetes control are strong influencers of the disease. Signs of autonomic neuropathy can be found in 20% of cases, again in strong correlation with age and disease duration as well as microangiopathy.

Q. In this condition, when is limb amputation indicated?

A. If the patient is diagnosed in later stages of the ulcer, limb amputation is indicated.

Q. Are diabetic ulcers and diabetic foot ulcers different?

A. There is no difference.

Q. Does family history play a role in diabetic foot ulcers?

A. Yes as family history plays a role in diabetes, it also plays a role in diabetic foot ulcers.

Q. Does diabetic ulcer occur only in the foot?

A. It occurs mainly in the foot and sometimes in other places. 

Q. How often is a review necessary for people with diabetic foot ulcers?

A. A weekly review is required for people with diabetic foot ulcers.

Q. What is cellular dysfunction of wound healing?

A. Diabetic foot lesions cause a complex dysfunction of cellular wound healing. In addition to general impairing factors of wound healing such as age, fluid and nutritional status as well as hyperglycaemia, the system character of diabetic disease causes alterations at the cellular level. These include disturbed microcirculation, reduced inflammatory reaction, reduced fibroblast proliferation, and an altered cytokine-protease profile.

Q. What is the treatment for diabetic foot ulcers?

A. The first step in the treatment of diabetic foot ulcers is to remove necrotic wound tissue from the wound. It is essential that the method of debridement utilized does not damage the nerves, tendons, and blood vessels. Since many people with diabetes don’t feel pain from the wound site, health care practitioners can’t rely on the patient to let them know when sensitive areas are being examined. The debridement will:

– Reduce pressure on the ulcer.

– Stimulate wound healing.

– Allow the healthy underlying tissue to be examined.

– Help the wound to drain.

– Optimize the effectiveness of the wound dressing.

Q. What is infection prevention?

A. Aggressive infection control is necessary to prevent infection. High morbidity and mortality rates are associated with diabetic foot ulcers which means oral and topical antibiotics are recommended if there is any sign of infection. Typically, wound dressings impregnated with antimicrobial agents are used. Simple gauze may actually damage the skin. Alginate and foam dressings provide high absorbency for moderate to heavy exudate. For a diabetic foot ulcer with dying tissue, hydrogels or dressings with collagen and silver are most effective. Most important is matching the absorptive ability of the wound dressing to the amount of wound drainage.

Q. What are advanced foot therapies for diabetic foot ulcers?

A. Physicians of individuals with diabetic foot ulcers may have difficult decisions to make if wounds don’t heal. Many of these patients have a significant cardiac risk and health care practitioners need to make complicated decisions about whether to perform invasive procedures like angiography. Other options can be:

– Covering the wound with cultured human cells.

– Heterogenetic dressings or grafts with recombinant growth factors.

– Hyperbaric oxygen therapy.

Q. How can one prevent a diabetic foot ulcer?

A. Individuals with diabetes should be instructed to:

– Examine their feet daily with a mirror and to look carefully for fungal infections or any abnormality.

– Wash and dry feet at least once a day in lukewarm water (tested with elbow), paying special attention to dry between the toes.

– Not use heating pads or put feet close to heaters.

– Always use footwear inside and outdoors.

– Use close-toed shoes if they can’t feel their feet.

– Always use socks and change them daily.

– Treat dry feet with lubricants containing urea or salicylates.