These are very common blisters and ones that we see in clinic a lot of the time, they are mainly due to a biomechanical/ dysfunctional issue, where the function of the big toe has been compromised and there is an increased amount of pressure on that area of the toe causing increased shear and blisters.
The lack of footwear width in the toe box are of the shoe is another common cause
How to help prevent these blisters
Assess if your footwear is wide enough in the toes box, often shoes can be wide enough where the big toe joints are but not in the toe area as they can cut off too soon.
applied to junction of the shoe fabric of the shoe that corresponds to where the blister is on the toe.
If you are unsure where the toe is relation to 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, then apply the oval engo patch on the marked area on the shoe
for the whole shoe, allows the large toe joint to work harder and then puts less pressure of the side of the big toe that is blistering
Silipos toe sleeves
are applied over the whole big toe, either with the end in or the open-ended ones, both will decrease the amount of shear applied to the edge of the big toe. Width of the footwear has to be there at that point too otherwise it will increase the pressure
Armaskin socks again will decrease the shear on that area of the big toe but only if the footwear is wide enough at that point.
Hoka oneone running shoes and boots
are designed with a large shock absorbing sole and a slight rocker in the sole. What this means id the big toe joint works better and takes the pressure from the edge of the big toe. Less pressure means less shear which leads to blister prevention, they make wide fitting shoes as well
Biomechanical Assessment is probable the next step, 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, a 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.