It owes to the traumatism continued due to the existence of a position of the foot on having trodden in the shape of duck (with the feet in angle). Of another more technical form we can say that the existence of a hallux valgus can provoke the development of a painful sinovitis in the joint metatarsofalángica of the thumb.

The treatment of the bunions consists in:

• Sneakers with high and wide toecap.
• An arch support of length of rut with a flange for the bunion, or Morton's expansion that spreads up to the top of the first finger, so that there gets depressed the area next to the internal part of the joint metatarsofalángica and the annoyance bunion is protected.
• A varo block to block the pronación (opening of the feet) excessive.
• The feet pronados need a type of footwear that has a straight staff, in order to obtain a major support for the internal part of the foot. For the foot I dig (with very much bridge) the flexible or combined staff turns out to be appropriate.
• The laying of a bar of 0,5 cm gum under the sneaker makes to diminish the pain due to the bunions, being effective also when there are painful limitations of the mobility of the thumb (hallux rigidus or hallux limitus).