Diabetic Ulcers / Diabetic Wounds
Diabetic foot ulcers are complex, chronic wounds, which can have a major long-term impact on the morbidity, mortality, and quality of life for an individual. People who develop DFU are at greater risk of complications than those without a history of DFU, so that is why there is a need and huge campaign within healthcare settings to avoid and prevent their development in the first place. Complications from DFUs can lead to an individual needing an amputation, this is often a life-threatening and scary outcome for the individual but one that is often the last resort.
For this to arise the DFU would have an infected wound/tissue that is posing a risk to the individual’s life with sepsis or even infection of the bone (osteomyelitis), and so to save the individual the dangerous tissue needs to be removed. Hinchcliffe et. al (2012) estimates that every 20 seconds a lower limb is amputated due to complications of diabetes. DFUs are relatively common and can have a major economic and social impact on the individual and their families.
Unlike other chronic wounds, the development and progression of a DFU is often complicated by wide-ranging diabetic changes, such as nerve damage, reduced circulation, and abnormal plantar pressure through the foot. Successful diagnosis and treatment of patients with DFUs involve a holistic approach that includes:
- Optimal diabetes control
- Effective wound care
- Infection control
- Pressure relieving strategies
- Restoring blood flow
According to Singh et. al (2005) around 25% of people with diabetes will develop a diabetic foot ulcer during their lifetime.
How are persons with diabetes prone to wounds on their feet?
Excessive or abnormal foot pressure, resulting from limited joint mobility, often combined with foot deformities, is a common cause of DFUs in individuals with reduced nerve sensation (Singh et. al 2005). Most Diabetics have some mild to severe nerve damage from the high glucose levels in the body. An individual may have an altered gait or atypical walking patterns as well. The altered biomechanical loading of the foot can result in hard skin, which increases the abnormal pressure and can cause changes in the skin itself e.g bleeding, scar tissue, fibrosis. Hard skin is caused by intermittent pressure against the top layer of skin (epidermis) and friction/shear force from altered movement of the foot.
With reduced nerve sensation, an individual may continue to walk on these vulnerable areas until a wound arises. Reduced nerve sensation causes them to have less perception of pain, pressure and temperature. Paul Brand says “Pain is the gift that nobody wants” but it is also the unique way the body communicates that there is damage arising to the bodies tissues. Reduced circulation from high glucose levels can cause the tissue to be fragile. Poor circulation also prevents sufficient nutrients/oxygen to allow normal healing to arise.
What does a foot with nerve damage look like?
- High arch
- Lesser toe deformities (claw, hammer, mallet, crossing over)
- Fatty pad atrophy/ muscle wasting along the arch
- Gait changes- foot slapping, knock knees, duck walking
- Bunions, Big toe stiffness/arthritis
Taken from Bakker et al, 2012.
Minor trauma to these areas can cause a chronic ulcer to develop. Trauma can be caused by poorly fitted footwear (slippers/sandals), walking barefoot, an acute injury (walking on broken glass, stone or sharp objects). In some cultures sitting cross-legged can cause injury to the skin at the ankle or on the top of the foot if sitting in a prayer position.
What can you do to avoid DFU development today?
Individuals with diabetes with no DFU or history of them can have a pressure scan taken by their Podiatrist to highlight abnormal areas of plantar pressure. This scan is utilised to gather data on the areas where an individual is at high risk of tissue breakdown or ulcer development. This is different form a foot scan done at health shoe shops. Medical grade scans offer advanced sensors that detect the smallest amount of pressure deviations. Ideally, this should be combined with a video analysis for further accuracy.
Wound offloading is sometimes more important than wound treatment. The podiatrist can prescribe an offloading device known as an orthotic, for the individual to wear within their shoes. Orthotics are useful devices that an individual can wear daily as a proactive step towards keeping their foot and tissues healthy and away from dangerous diabetic foot ulcers. They are comfortable devices and are used as a treatment and as a prevention. It is important to mention that ready-made orthotics, in this case, can be very dangerous and may exacerbate the problem.
Example of a Diabetic foot with ‘at risk’ high pressures