Which deformity may accompany hallux abducto valgus during foot assessment?

Hallux abducto valgus, commonly known as a bunion, is characterized by an abnormal angle between the first metatarsal and the hallux (big toe) that leads to lateral deviation of the toe. This deformity can indeed accompany various changes in the foot structure and function, including forefoot abductus, the development of plantar calluses, and flattening of the arch.

When evaluating the foot of a person with hallux abducto valgus, forefoot abductus is often observed. This occurs as the first metatarsal moves laterally, resulting in a wider forefoot stance. This shift can create a chain reaction affecting the alignment of the remaining toes and the distribution of weight during walking.

Plantar calluses frequently develop as well, particularly under the second and third metatarsals. This occurs due to abnormal weight distribution caused by the altered mechanics of the foot, leading to increased pressure in specific areas. The presence of a bunion can exacerbate these conditions by causing changes in gait and foot posture.

Finally, flattening of the arch can result from long-term alterations in foot mechanics. The structural imbalance created by hallux abducto valgus can place additional stress on the ligaments and tendons, potentially