Metatarsus primus varus is a foot deformity that affects the angle of the bones of the big toe.

It’s also associated with abunion, which is a bump on the side of the big toe.

Bones Affected In Metatarsus Primus Varus

This condition involves the metatarsals and phalanx bones of the foot.

Close up of woman’s feet with red toenail polish

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It may also cause swelling, tenderness, skin irritation, blisters, and pain.

An inflamed bursal sac may develop, but that’s a result of a bunionnot a cause.

In rare cases, a bone anomaly in the metatarsophalangeal joint may contribute to the issue.

However, genetics are also considered as a possible cause.

Problems related to metatarsus primus varus and bunions develop over time and do not generally get better without treatment.

These conservative treatments do not, however, correct the metatarsus primus varus or hallux valgus problems.

American Academy of Orthopedic Surgeons.Bunion.