Hallux valgus is the most common deformity of the forefoot and toes. Because of its conspicuous shape, it is also called a bunion or ganglion. It is a deformity of the metatarsophalangeal joint of the big toe. The big toe deviates outwards and displaces the other toes. A painful, inflamed protrusion often forms at the metatarsophalangeal joint of the big toe.

Hallux rigidus is arthrosis of the metatarsophalangeal joint of the big toe. This causes the joint to become inflamed and the joint space to narrow. This leads to a restriction in the mobility of the big toe.

Although these are two separate indications, the causes of the development are often identical. Thus, the therapy to eliminate the causes as well as to relieve the pain is also independent of the specific indication.