Blisters on the Side of Your Foot

What Causes side of foot blisters

These blisters are where the skin gets caught between the insole or footbed, and the upper of the shoe and can present as blood blisters.

Footwear- The width of your shoe is not wide enough on these areas and they pinch the skin causing a blister. If you measure around the 1st and 5th toe joints it is considered to be the widest part of your foot and the shoe manufactures base their shoe sizes on that area being the widest part of the shoe. So if you buy a wide fitting shoe, this where the width of the shoe would be at its widest.

roof off blisters under foot

Bunions- of the big and little toe, sadly these are inherited, so you can really blame the parents for this one!

Sandals- If the edge of the foot hangs over the sandal then that exerts a pinching pressure and creates a blister, more often a blood blister. Moulded (shaped) sandal or shoe soles can have the same effect, where the edge of the sole cups the heel, if the heel of the foot is bigger than the sole, it will receive pressure from the edge of the sandal and the skin will blister. If the insole in the shoe has creased or moved, it can change the dynamics of the foot in the shoe. Maybe the shoe has had its day, we often see patients wearing well-worn shoes that are changing the way they walk as the shoes are so badly worn.

Orthotics- either prescription or off the shelf ones can cause pressure if the  orthotic is slightly too small , this could because the casting was taken early in the morning or when the foot was cold and some feet expand by the end of the day with temperature changes. This applies to buying the ones form the shop too.

How to prevent side of foot blisters

Engo patches on the edge of the shoe that corresponds to where the blister is on the toe, if you are unsure where the toe is relation to a the insole, then put a fabric plaster on the toe that is affected by the blister, mark it with a permanent marker pen and put your foot back in the shoe, the black marker pen should rub off onto the shoe. Accurately marking the area of pressure in the shoe, you can put the engo patch on the marked area on the shoe

Poron insoles for the whole shoe, poron allows the big knuckle to work harder and therefore will require less demand of function of the smaller joint under the big toe to do the work, when walking. This really is the mechanics of the foot anatomy, which podiatrists know very well, that if one joint doesn’t work very well, the body will ask the nearest joints to it, to work harder, otherwise we wouldn’t be able to walk at all!

Silicone gel big toe sleeves. The sleeves are put over the whole toe, either with the end or not and they decrease the amount of shear applied to under the big toe.

Armaskin socks- again will decrease the shear on that area of the big toe.

Running shoes and boots are designed with a large shock absorbing sole and a slight rocker in that sole. What this means from a functioning point of view is the big toe joint can drop into the shock absorbing sole without the jamming from a hard floor surface, allowing it to increase its workload therefore in turn, asking for less movement at the area that is blistering. Less pressure- less shear- no blister formation. This is Biomechanics of the lower limb and with abnormal compensation, causing pain and issues with the feet and ankles.

Increase the width of the shoes, there are plenty of shoe manufacturer’s that provide extra width fittings in shoes for any activity, New Balance- are great for running, walking and casual activities, Clarks are another for casual shoes. If you are a walking or running female, then switch to male shoes as they are always more generous in their width fitting.

Biomechanical Assessment is needed to be done by a Podiatrist if all the measures above have failed to resolve the blisters on the big toe. They will be able to establish why the joint is experiencing an increase of pressure to cause the blister in the first place, the podiatrist may be able to make a simple insole or a prescription orthotic to solve the Biomechanical cause of the blister. You maybe also experiencing ankle, knee, lower back and sometimes neck pain which could very well be caused by the big joint dysfunction. I know this sounds very odd but this is a perfectly normal presentation of symptoms for a podiatrist to see.


What is a blister "hot spot"?

Hotspot - If you have recognised a hotspot on the skin in time before a blister has developed then a simple island dressing will be enough to reduce the shear on the skin and hence reduce the blister from forming further and if you have them, apply an Engo patch on the insole as explained in the prevention of blisters. Deflective padding works really well here to reduce the pressure on the joints.

Treating Bubble blisters

Bubble Blister - If the roof is still on then treat it in a similar way to a hotspot on the skin, by applying a sterile island dressing, if the blister bursts (pops) when the dressing is on, then you know the dressing is already sterile and will prevent an infection from getting into the open sore. If you decide to pop the blister, then follow the instructions on “how to pop your blister” and treat it as a roof torn blister. Use an Engo patch applied to the insole, with deflective padding applied to the feet.

Treating broken blisters

Roof torn blister - now this type needs its roof (skin) to stay in place, the roof may be broken but your own skin is still important for healing, so use a sterile saline swab to clean the wound first, then apply the povidone iodine stick over the torn area as an antibacterial action and apply a sterile island dressing. A deflective pressure relieving padding as shown in the video to prevent any further pressure and friction.

Treating "popped" blisters

Roof off blister - Hydrocolloid dressing is the only option for this stage of blister, swab the area with saline to make sure the wound is clean and dry before applying the hydrocolloid, add extra hyper fix tape to anchor it down and apply deflective padding if continuing an event or activity. Hydrocolloid dressings are great wound healers and Podiatrists have been using them for a long time in the management of ulcers, with great success. They are not used at any other stage of the blister treatment and can cause blisters if not applied at the correct stage. I like to use some fleecy foam padding over the dressing as it just gives a bit of cushioning to the blister area, which is always very painful.

Treating infected blisters

Infected blister this is the stage of blister that you need to recognise quickly, a bacterial infection has invaded the blister and it could look red, swollen, there may be yellow or green pus in the blister and it could smell? Extending into the skin around the blister might be red and hot with red lines tracking away from the blister. You may feel unwell in yourself and swing from having the chills or feeling quite feverish. This is the time to get medical help as the infection can easily travel into the blood stream causing the infection to move into the leg and cause sepsis.