Cause
Bunions can occur for a number of reasons but most commonly develop due to poor foot mechanics.  While bunions are not inherited, if there is a history of bunions in the family the development is much more likely.  Bunions form when the normal balance of forces that are exerted on the joints and tendons of the foot becomes disrupted.  This causes instability of the joint leading to deformity.  Over years of walking with these imbalances in the foot structure, the bunion slowly develops.  While shoes aren’t a direct cause of bunions, tight shoes may cause pain by putting pressure on the “bump”.  Pointed toe shoes can cause someone already predisposed to develop a bunion faster.  To minimize your chances of developing a bunion, never force your foot into a shoe that doesn’t fit.  Shoes that conform to the shape of your foot are always best.  Look for shoes with a good arch, broad toes and soft soles.  Avoid shoes that are short, tight or have pointed toes and those with heels higher than 2 ¼ inches.  If you are already developing a bunion, wear shoes that are roomy enough to not put pressure on it.  This should help relieve most of your pain. Other causes include injury, gout, and neuromuscular disorders.

Signs/Symptoms
The most common symptom is a painful bulging bump on the inside of the base of the big toe.  Surprisingly, the degree of deformity may be quite out of sync with the pain level.  Some patients have a severe bunion deformity with very little pain while others have an almost normal appearing foot with a lot of pain.  X-rays will generally reveal a prominent bony bump at the base of the big toe with an increased angulation between the first and second metatarsal--  the long bones in the forefoot that connect each toe with the rest of the foot.  If the bunion has been present for many years, patients often experience arthritis at the big toe joint.  Redness may occur on the bunion at the point of maximum tenderness.  Occasionally a “bursa” may develop at the site.  With severe bunions the big toe may crowd the second toe causing it to elevate and rub on the top of the shoe.  The second toe ultimately develops into a hammertoe as a result.

Treatment
Conservative treatment includes physical therapy, padding, taping, wearing comfortable shoes and taking oral anti-inflammatories.  Unfortunately these conservative treatments are not always effective and surgery is frequently needed. 

Bunion Surgery

There are over 60 different types of bunion surgeries, depending on the condition.  Fixation techniques include even more variables, involving screws, staples, absorbable screws, pins and plates.

With severe or long-standing bunions, the joint cartilage may become damaged or destroyed.

Cartilage does not regenerate. Once it's gone, it's gone. For bunions with damaged cartilage, simply straightening the bunion deformity will not alleviate the pain.  That's because the joint is arthritic, and there's bone-to-bone rubbing. When the cartilage is significantly damaged, an implant may be required. There are several different types of implants on the market.

An alternative to an implant is joint fusion.  The decision to fuse the joint or use an implant is based on the patient's age, activity level, gender and lifestyle.  Fusion can be performed with screws, staples or pins, but is most often accomplished with a plate.  Plates provide for a much more stable and reliable fusion technique.  While fusions do limit range of motion, the toe remains functional with this more permanent treatment.  Patients who opt for fusion may have difficulty wearing high-heeled shoes, but otherwise experience little or no restrictions with regard to footwear.