Hallux valgus is a deformity of the first ray in which the great toe is deviated towards the second toe. There is normally a deviation of the first metatarsal towards the midline (metatarsus primus varus).
Hallux valgus usually becomes symptomatic when the first metatarsal deviates so much it rubs on the shoe, or when the great toe rubs on the second.
However, hallux valgus is quite a complex deformity. We will begin by examining the components of the deformity, then looking at how the normal control mechanisms of the first ray are lost.