Risk Factors of Ulceration

What is peripheral neuropathy? While it is still unclear what causes this nerve damage throughout the body, peripheral neuropathy (or PN) is a long term complication of diabetes and affects about 75% of those with the disease. It also is associated with people with Hansen’s Disease (or leprosy), those with B-12 deficiency anemia and those with chronic alcoholism. In a study published in the New England Journal of Medicine (January 27, 2005) several modifiable risk factors were associated with developing peripheral neuropathy. They included high triglycerides, high BMI, smoking and hypertension. Interventions directed at these specific factors may decrease the incidence of peripheral neuropathy and subsequently decrease the risk for ulceration and amputation.

For many with diabetes, neuropathy is the first symptom they notice. On average, the symptoms occur within 10 years after diabetes onset.

 

There are three types of neuropathy.

Sensory neuropathy causes changes in pain, temperature and pressure sensation, especially in the feet and legs. This loss of protective sensation can be identified by using the Semmes-Weinstein 5.07(10 G) monofilament. The monofilament is applied to 10 different sites on the foot. The inability of the person to feel the monofilament indicates that their sensation can’t be trusted to prevent injury, and they should be warned to NEVER walk barefooted.

Autonomic neuropathy involves the autonomic nervous system and affects the cardiovascular, gastrointestinal and genitourinary systems, cutaneous blood perfusion to the soles of the feet, and thermoregulation. An obvious sign of this is the dry skin on the feet and fissures on the heels due to anhydrosis. These breaks in the skin provide a great opportunity for infections to gain a foothold.

 

Motor neuropathy: With motor neuropathy there is atrophy and wasting of the small intrinsic muscles of the foot, which contribute to the structural deformities seen with many patients (examples include claw and hammer toes, bunions and increased pressure on the metatarsal heads). Structural deformities contribute to ulceration.

 

•Impaired Vision •Past history of ulcer or amputation •Male gender •Increased age •Ethnicity •Poor footwear The goals of assessment and intervention for anyone at risk for foot ulceration include: 1. prevention of injury in the first place by educating patients and their caregivers and clinicians about performing regular and routine foot care, and managing their blood sugars and blood lipids well. 2. prompt evidence-based treatment of the ulceration which should include: aggressive serial sharp debridement of the ulcer and any callous; revascularization if poor perfusion is identified; treat bone and soft tissue infections aggressively; use topical advanced wound care products to promote the healing and rapid closure of the wound, and keep the pressure off the foot ulcer with offloading strategies 24/7.   There's no safe amount of pressure when a need for offloading is identified.

Major Culprits: Peripheral Neuropathy and Vascular Insufficiency

•Sensory Neuropathy •Autonomic Neuropathy •Motor Neuropathy

What is peripheral neuropathy? While it is still unclear what causes this nerve damage throughout the body, peripheral neuropathy (or PN) is a long term complication of diabetes and affects about 75% of those with the disease. It also is associated with people with Hansen’s Disease (or leprosy), those with B-12 deficiency anemia and those with chronic alcoholism. In a study published in the New England Journal of Medicine (January 27, 2005) several modifiable risk factors were associated with developing peripheral neuropathy. They included high triglycerides, high BMI, smoking and hypertension. Interventions directed at these specific factors may decrease the incidence of peripheral neuropathy and subsequently decrease the risk for ulceration and amputation.

For many with diabetes, neuropathy is the first symptom they notice. On average, the symptoms occur within 10 years after diabetes onset.

 

There are three types of neuropathy.

Sensory neuropathy causes changes in pain, temperature and pressure sensation, especially in the feet and legs. This loss of protective sensation can be identified by using the Semmes-Weinstein 5.07(10 G) monofilament. The monofilament is applied to 10 different sites on the foot. The inability of the person to feel the monofilament indicates that their sensation can’t be trusted to prevent injury, and they should be warned to NEVER walk barefooted.

Autonomic neuropathy involves the autonomic nervous system and affects the cardiovascular, gastrointestinal and genitourinary systems, cutaneous blood perfusion to the soles of the feet, and thermoregulation. An obvious sign of this is the dry skin on the feet and fissures on the heels due to anhydrosis. These breaks in the skin provide a great opportunity for infections to gain a foothold.

Motor neuropathy: With motor neuropathy there is atrophy and wasting of the small intrinsic muscles of the foot, which contribute to the structural deformities seen with many patients (examples include claw and hammer toes, bunions and increased pressure on the metatarsal heads). Structural deformities contribute to ulceration.

 

Inadequate blood flow in the legs:

Vascular insufficiency (damage to the blood vessels leading to the legs and feet), is more common among people with diabetes, and may be present with neuropathy. This causes poor circulation in the lower limbs eventually leading to tissue death.

The lower legs will typically appear edematous, often with hyperpigmentation from chronic venous stasis.