Chronic wounds differ from normal acute wounds as they do not glide through the stages of healing as easily.
If a person suffers an acute wound from falling over and cutting themselves, it will generally heal up quite quickly.
Chronic wounds occur when the wound remains present for longer than the usual amount of time a wound should take to heal.
Chronic wounds on the feet can occur for a variety of reasons and it is extremely important to have these assessed and treated by your podiatrist or GP. This is because wounds that are left untreated can result in severe complications or even amputation.
To understand how a wound is treated, the first step is understanding what has caused the wound in the first place.
Types of wounds
Neuropathic wounds:
Neuropathic wounds occur when the wound has been caused by a loss of sensation to the feet.
Damage to the sensory nerves is called sensory neuropathy, which often occurs due to diabetes or alcohol abuse.
A person with sensory neuropathy loses the ability to feel their feet, and often they do not realise that a wound is present on their foot, as they do not feel any pain.
Examples of this include patients having a rock in their shoe and it causing a wound as they continue walking with it in there, or patients who sleep with a hot water bottle to keep their feet warm, but end up with severe burns as they cannot feel when the temperature is too hot.
The good news is, if a wound is purely neuropathic, blood flow may still be excellent, so once your podiatrist or GP begins to treat them, they often respond very well!
Arterial wounds:
Arterial wounds are those that occur due to a lack of blood getting down to the feet.
These wounds often occur due to areas of high pressure and may start as something as simple as a blister. But due to there being no blood flow down to the feet, these small wounds struggle to heal and instead get worse and worse as time goes on.
If no blood is getting down to the wound, it is important to see a vascular specialist to see if surgical intervention is necessary.
These wounds are extremely important to monitor, as they are very susceptible to infection, and amputation.
Venous wounds:
Venous wounds occur when the veins in the lower limb fail.
This results in pooling of blood and fluids in the lower limbs, and when this fluid has nowhere else to go, it sometimes begins to break the skin barrier.
These types of wounds typically present in a location known as the ‘venous triangle’, an example of this is shown in the picture to the right.
Pressure wounds:
Pressure ulcers are quite self-explanatory – they occur as a result of an area of high pressure.
Pressure ulcers are very common in people that are bed bound for long periods of time, or bed bound and unable to move at all.
On the feet, these usually occur either on the tips of the toes from bed sheets rubbing, or on the backs of the heels from the bed itself.
It is also common to see these near the hips, which are referred to as lumbar ulcers.
Many measures are put in place in the hospital setting to ensure that pressure ulcers are avoided whenever possible. These include bed wedges to offload the heels, and bed cradles to hold bed sheets off the toes.
Pressure wounds will be graded according to the chart below. This involves four stages of pressure injury, as well as two other grades being ‘suspected deep tissue injury’, and ‘unstageable’.
The first four stages progress as you would expect, ranging from redness on the skin to a full thickness wound, which surpasses the epidermis and may expose tendon, muscle, or bone.
Wounds are graded as suspected deep tissue injury when the skin barrier has not been broken, so the wound may appear as a stage 1 injury, but it is suspected that underlying this there is a deep wound or abscess. If the area presents as very soft and boggy, this is often how a wound will be graded.
The final grade is referred to as unstageable, and wounds will be graded as this when an ulcer is covered by either a dry eschar, or necrotic tissue which makes it impossible to identify how deep the wound goes. In this case, the podiatrist will generally have to remove the tissue blocking wound to investigate the severity of the wound.
Diabetes and wounds – how are they linked?
You may have heard the term diabetic foot ulcers before, or people having their legs amputated due to complications from diabetes.
You might be wondering what causes people with diabetes to be more susceptible to wounds and their complications, and this is where an understanding of the causes of chronic wounds is important.
Diabetes can result in a variety of complications, particularly if blood sugar levels are not well controlled.
Two of the most common complications are reduced blood flow to the feet, known as peripheral arterial disease, and damage to the sensory nerves to the feet, known as sensory peripheral neuropathy.
As was discussed previously, loss of blood flow to the feet can result in arterial wounds, and loss of feeling to the feet can result in neuropathic ulcers. This is a nasty cycle that diabetic patients can find themselves stuck in, as they may develop a neuropathic ulcer due to their neuropathy, or lack of feeling, and then they are not able to heal this wound as there is limited or no blood getting down to the wound. At this point if an infection sets in, antibiotics are not able to work effectively, as they travel through the blood, thus antibiotics are not able to get down to the feet and fight off the infection.
This can result in a referral to a vascular specialist, where a surgeon will try to increase the blood flow down to the feet. A way they can do this is by placing stents in occluded arteries or rerouting blood flow via bypass.
If this is not successful, amputation may be the only option left to stop an infection from becoming systemic and life threatening.
How are wounds treated?
There are a few principles that your podiatrist will follow to give a wound the best chance to heal.
This includes promoting ‘moist wound healing’ by selecting the correct primary and secondary dressings and offloading the wound by any means necessary.
This may include the use of multiple layers of felt stuck to your foot, as can be seen in the image below.
Reducing pressure at the wound site to allow it to heal is crucial when treating chronic wounds.
Techniques may involve casting the limb, or the use of a moon boot, similarly to how a broken bone in the foot may be treated. In the long term, orthotics may be required to alter the way your foot distributes pressure through its sole.
What can be done to prevent chronic wounds?
As there are so many factors that go into the development of chronic wounds, there are also a lot of factors that go into preventing the development of these wounds.
Pressure wounds will be prevented to the best of the ability of nursing staff or doctors using the techniques discussed previously.
However, for the prevention of arterial, venous or neuropathic ulcers, most factors revolve around living a healthy lifestyle and if you have diabetes, controlling your blood sugar levels to the best of your ability!
Here are our biggest tips for avoiding the development of arterial, venous or neuropathic wounds.
- No smoking! It is very well known that smoking can cause arterial disease. Arterial disease puts you at an increased risk of chronic wounds, and is a huge barrier to healing any wounds which will develop. This is on top of the countless other risks that smoking poses to your health, so talk to your GP about putting a plan in place to quit smoking.
- Limiting your alcohol intake: Alcohol abuse is the second most common cause of neuropathy following diabetes. Talk to your GP about limiting alcohol intake and drinking in responsible amounts.
- Exercising regularly: Exercise is the best thing you can do to keep your heart strong and your blood vessels healthy! This goes a long way in ensuring that any wounds that develop remain an acute wound, not a chronic one.
- Monitoring your feet regularly: If you have neuropathy, your body can no longer tell you something is wrong with your feet by sending signals to the brain that are perceived as pain. For this reason, you have to use your eyes to ensure your feet are healthy. Check your feet every single day! If you are unable to do this, have someone else check them for you as often as possible.
- Be in regular touch with your GP: Your GP will let you know if you are at an increased risk of developing wounds and will be the best person to advise you on living a healthy lifestyle, so be in regular touch with them!
And if you have any issues with chronic wounds on your feet, or any pain and/or discomfort in your feet or lower limbs, come see us here at Watsonia Podiatry. Book online or call us today on 03 9432 2689 for an appointment!