On June 1st and 2nd of this year, Chicago hosted the 11th annual Avon Breast Cancer Walk, Chicago. Participants walked 39 miles through Chicago and helped raise more than $5.2 million to advance access to care and find a cure for breast cancer (1). What an amazing effort on their part This year marked my 3rd year of volunteering in the podiatry tent. This marked another opportunity to treat the ailing feet of participants who mostly battled the blisters that inevitable come from such a long trek in such a short time.
Blisters are a common problem that all people have probably dealt with. I know that I have had my fair share of blisters, mostly from participating in sports and not knowing how to prevent them. I’ve actually bought the exact same shoe for basketball and other court sports just because I can prevent blisters. I remember set of blisters that I developed after playing basketball for several hours that covered the entire ball of my foot, had blisters within the blister, and extended up into my big toe. Talk about painful!
Why do I get blisters?
Blisters are fluid filled sacs that form in the outer layers of skin due to friction. As the skin repetitively rubs against a surface, fluid builds up. In the diagram below from drymaxsocks.com, it shows that when the socks get wet and stuck to the skin, the frictional “shear” force is transferred from the socks to the layers of the skin. The tips of the toes, over joints and over the heel are common places for blisters to form.
Blister prevention is accomplished by taking the friction and transferring it to another material. This is a very simple list of prevention options. Newer “blister prevention” products can be found at any pharmacy. Most products work by reducing friction on the skin and seek to take the shear forces into themselves.
1. If your shoes have enough toe room, wear two pairs of socks. This is the easiest solution.
2. Applying petroleum jelly to areas that rub, then put your socks on. Put foot powder in the shoes. (make sure there is a sock layer between the petroleum jelly and the foot powder)
3. Apply moleskin to cover the areas where you get recurrent blisters and allow the moleskin to wear off rather than pulling it off.
4. Several weeks before a long hike or anticipated event, apply tincture of benzoin or soak with tannic acid daily for three weeks in order to toughen the skin.
5. Break in new shoes several times before using them for a long hike or event.
6. To prevent blisters under toenails, tug on the end of the sock to make it less tight.
Stages and Treatment
Treatment depends on the stage of formation of the blister. Breaking down blisters and what to do with them:
1. “Hot Spots” – These are defined as areas of redness that indicate rubbing in the shoes. These will appear prior to the blister formation. Treatment: Cover with moleskin, stop wearing the shoe that causes the problem
2. Closed blisters – You classic blister with fluid buildup underneath the surface of the skin. If you don’t drain these, they will keep getting bigger! Treatment: Drain with multiple small openings using a sterilize needle, puncturing the blister at the base, where the blister elevates from the skin. Protect against further friction as mentioned above in the prevention section. DO NOT deroof the blister. The roof of the blister acts as a “biological” bandaid which promotes faster healing.
3. Open Blisters – Hopefully, you’ll never get blisters this bad! The underlying new skin is not ready for the rigors of protecting the underlying skin and is VERY sensitive! Treatment: Trim, clean, and use ‘donut’ pad to protect against additional friction. Fill the donut hole with triple antibiotic and cover with a bandage.