Bunion correctors are a night splint or brace that are supposed to straighten the big toe when there is a hallux valgus present.
There is a lot of debate and discussion if they actually work or not. Opinion is divided and the research evidence for them is sparse. One study does show they they do help a small amount in the short term, but no research has looked at them over the long term.
The reason for the divided opinion is that a lot of force from the biomechanics and shoes during the day time goes into producing the valgus position of the toe and how can a splint just worn for the night over come that? Any good done during the night is likely to be undone the next day walking around. Obviously more research is needed to sort this put.
There is some commentary that they are still beneficial to use even if they do not correct the toe by much as they will keep the toe and joint mobile and flexible, which has to be a good thing.