It's a bit confusing, but the word bunion actually refers to three different medical conditions: soft tissue enlargement, hallux abducto valgus and metatarsus primus varus. All three of these problems usually occur together and are what most people think of as a typical "bunion."
Soft Tissue Enlargement Is Hallmark Sign of a BunionThe true definition of the word bunion, is an enlargement on the side of the foot near the base of the big toe (hallux). The enlargement is made up of a bursa (fluid-filled sac) under the skin. Technically, the term bunion is just the soft tissue enlargement that occurs. Take a look at more bunion photos.
Two Other Conditions Often Affect Bunions, Too
The soft tissue enlargement usually occurs because of two structural deformities in the foot bones, called "hallux abducto valgus" (HAV) and "metatarsus primus varus (MPV).
HAV is a fancy way of saying that your big toe (hallux) is rotated and leaning toward your other toes. Sometimes the deformity becomes really severe and the big toe can either sit on top or underneath your second toe.
The other condition, metatarsus primus varus, involves the first metatarsal becoming rotated and leaning too far toward your other foot. The hard bone you feel when you touch the bunion (the side of your big toe joint) is the head of the first metatarsal that has shifted out of position.
Bunions are much more common in women than in men. Some suggest this is due to the poor fitting shoes women wear.
Causes of "Bunions"Are shoes to blame? Yes and no. Research studies have shown that in countries where people do not wear shoes there are not as many bunions, but bunions are still found in some non-shoe wearing people. In countries where people do where shoes, there is a greater number of people who have bunions, but not everyone who wears shoes gets bunions. That means there must be other factors besides shoes that contribute to bunions.
Studies have shown that 63-68% of people who have bunions have a family history of bunions. So, heredity definitely plays a part. You do not inherit the bunions, but you inherit the foot type that may lead to bunions. Certain foot types cause the bones to change position and go out of alignment. This in turn allows the muscles and tendons to take advantage over other muscles and tendons and over time these changes may lead to bunions. Take a look at the feet of your grandparents, parents, aunts, uncles, sisters and brothers. There may be bunions in your family that you were not aware of.
Other possible causes of bunions:
- Shoes (especially high-heeled shoes)
- Flat feet (pes planus) and pronation (foot rolls in)
- Metatarsus primus varus (first metatarsal bone rotates)
- Short or long first metatarsal bone
- Round first metatarsal head
- Hypermobility (excess motion) of the metatarsocuneiform joint
- Amputation of the second toe
- Neuromuscular disorders (cerebral palsy, poliomyelitis)
- Rheumatoid arthritis
- Contracture (shortening) of the achilles tendon
- Ruptured posterior tibialis tendon
- Ehlers-Danlos syndrome (hyperelasticity)
Signs & Symptoms of "Bunions"Bunions are usually termed mild, moderate or severe. Just because you have a bunion does not mean you have to have pain. There are some people with very severe bunions and no pain and people with mild bunions and a lot of pain.
- Pain on the inside of your foot at the big toe joint (1st MTPJ)
- Swelling on the inside of your foot at the big toe joint
- Redness on the inside of your foot at the big toe joint
- Numbness or burning in the big toe (hallux)
- Decreased motion at the big toe joint
- Painful bursa (fluid-filled sac) on the inside of your foot at the big toe joint
- Pain while wearing shoes - especially shoes too narrow or with high heels
- Pain during activities
- Corn in between the big toe and second toe
- Callous formation on the side or bottom of the big toe or big toe joint
- Callous under the second toe joint (2nd MTPJ)
- Pain in the second toe joint