Hallux Abducto-Valgus (Bunions)
A bunion (hallux Abducto-valgus) is a valgus deviation of the hallux, commonly associated with an Exostosis on the 1st Metatarso-phalangeal joint.
When irritated by tight or ill-fitting shoes, bunions can become red and swollen.
Bunions are most commonly caused by forefoot adductus and excess pronation of the subtalar joint. Some bunions are caused by arthritis or trauma.
Due to excessive pronation, forces load the medial forefoot area. This increased adductory load on the 1st metatarsal shaft causes rotation of the shaft, which then requires the hallux (big toe) to compensate by abducting.
Feet that have short 1st metatarsals or hypermobility are more susceptible to this condition.