Like ‘bunions’ there is so much misinformation on the web about this thing called ‘overpronation’. So much nonsense and so many myths are written about it. Unless you are familiar with all the issues, it can be hard to distinguish the good information from the bad information.
If you are on this site, then we assume you know what bunions are! ‘Overpronation’ is the term given to a situation when the ankle joint rolls inwards or medially too much. The problem with the term is that pronation is actually a quite normal motion and there is no consensus what is normal and what is over. This is why so much nonsense gets written on the web about it. Too much of the pronation is generally considered problematic (but not by everyone) and can increase the risk for foot and leg problems. One of those foot problems that it could be associated with is bunions.
What is the link between Overpronation and Bunions?
The potential for a link between the two comes about as there is good evidence that those with bunions or hallux valgus have more flat feet and those with flat feet (or overpronation) are more likely to have bunions or hallux valgus. There is a pretty reasonable theoretical mechanism how a flat or overpronated foot could lead to a bunion or hallux valgus, but that does not mean that the flat feet caused it. It could well be that people develop bunions and due to medial column weakness, the arch collapses. This could be the cause of the overpronation.
So it really is a ‘chicken or egg’ situation. Which came first? The pronation or the bunion (hallux valgus)? Some people think they know, but the don’t. there is no evidence one way or the other as to which one happens first.
Having said that, it is still important the the problem of any overpronation be addressed as pert of the management of bunions and hallux valgus. Clinical experience does support that there are better overall outcomes when it is addressed.