Hallux valgus is the medical term given to bunions. A bony lump present at the base of the big toe, while it is not known exactly what causes them, genetics and foot injuries are known to be factors.
The skin over the lump can also develop issues, namely become itchy and sore.
Tight and poorly fitting footwear are considered to contribute to bunion development, although it is unknown whether they can be a cause of them.
Bunions normally appear on the big toe, but can also develop on smaller toes. These are called bunionettes.