Bunions

History

Bunions are a common foot deformity that has been estimated to affect approximately 1% of the population. The incidence of the deformity has been found to increase with age due to the progressive nature of the deformity. The deformity begins with a leaning of the big toe, gradually changing the angle of the bones over the years and slowly producing the characteristic bump on the side of the big toe (Figure 1).

Figure 1 A Typical Bunion

Bunions have been thought to be caused by a variety of underlying conditions, such as faulty biomechanics of the foot, neuromuscular disorders, and arthritic conditions. The prevailing theory is that the deformity is caused by an inherited faulty mechanical structure of the foot. Thus, it is not the bunion itself that is inherited but certain foot types that make a person prone to developing a bunion.

The pain symptoms associated with bunions typically appear at later stages, well after the deformity becomes evident. These pain symptoms are typically aggravated by activity such as walking or running, as well as by shoes that create pressure along the bony prominence. However, some people with bunion deformities may never experience pain symptoms.

Although wearing narrow shoes that crowd the toes is not the cause of the bunion deformity, it can aggravate the pain symptom, causing symptoms sooner. Most individuals complain of pain in the area of the bony prominence. These pain symptoms are usually aggravated by pressure in the area. Occasionally, compression of a nerve by the bunion area will cause symptoms of tingling and numbness.

Bunion deformities in the athlete and the dancer may be particularly painful due to the snug fit of athletic shoes such as cleats and pointed shoes. Additionally, the strenuous activities may aggravate the area, creating a chronic inflammatory condition. Bunions are particularly prevalent in ballet dancers, and it is felt that while ballet itself is not the cause of the deformity, the forces through the foot during dancing produce an environment in which bunions may develop.

Physical Examination

Bunions can be recognized on visual examination of the foot. There is a characteristic prominence to the inside of the big toe joint with leaning of the big toe toward the second toe. In early deformities, the big toe joint is flexible and the deformity can be manually reduced. In later stages, the joint may stiffen, and range of motion diminishes.

In many individuals with bunions, there may be an associated hypermobility noted in the foot that may be a contributing factor to the development of the bunion. These individuals may exhibit a flat foot deformity. However, not all bunions are associated with flat feet.

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