Most people think every problem of the big toe joint is a bunion and want bunion surgery (bunionectomy) to saw the bunion away. It turns out there are several foot problems that look like bunions but are not.
A bunion is a bony prominence causing an enlargement on the side of the big toe. Bunions are not bone growths, rather they occur from a malalignment of the big toe joint causing the bone to push outwards. Bunion surgery involves repositioning the out-of-place bones.
Because bunions come in various sizes, it's not always clear if the problem is a bunion. So, before you sign up for a bunionectomy, learn about what other conditions masquerade as bunions and how to treat these foot problems.
Big Toe Joint Arthritis
Arthritis of the big toe joint is the most common bunion look-alike. One of the hallmarks of big toe joint arthritis, medically termed hallux rigidus, are bone spurs that form on joint as a result of the degenerating cartilage.
These bone spurs can be quite large and painful. The skin overlying the bone spurs can become red and inflamed, just like a bunion. Bone spurs with arthritis tend to occur on the top of the big toe joint, which is different from bunions where the bony prominence is on the side.
Bunions, however, can occur conjunct with arthritis of the big toe joint. X-rays would help determine the extent of arthritis and how/if it contributes to the bunion pain.1
Hallux Rigidus Overview
Ganglion cysts are firm fluid-filled sacs that occur all over the body, but when they occur around the big toe joint they can be confused with a bunion. A ganglion develops around a joint and often connects to the joint, which is where its fluid originates from.2
Ganglions can be distinguished from bunion by feel as ganglions are softer to the touch than a bunion. Because ganglions are fluid-filled they will transilluminate when a light is held adjacent to the cyst.
Gout is a common problem of the big toe joint causing it to become acutely red, hot and swollen. Bunions are also known to get reddish in color, from the direct pressure of the bunion within a shoe.
Gout is a condition where the big toe joint (and other joints too) develop internal crystals from an overabundance of uric acid in one’s bloodstream. These sharp crystals cause intense pain in the big toe joint.3
Sometimes gout is difficult to diagnose because blood tests may be normal. X-rays of the big toe joint may present gouty changes of the joint (known as gouty arthritis).
The biggest misconception with bunion surgery is that bunions are outgrowths of bone and can be shaved off. Bunions are not bone growths. However, the underlying bone may be enlarged and prominent, giving the appearance of a bunion.
It's common to see bony enlargements that occur with bunions, but they also occur when a bunion is absent. X-rays can easily identify whether or not there is a bony enlargement.
While the bunion surgery involves repositioning the malaligned bones, most procedures also involve shaving away any bony prominences at the big toe joint.
Bursitis is a common cause of redness and swelling that occurs over joints, often from overuse or direct external pressure. The big toe joint is susceptible to bursitis as it bears the entire load of the body during gait, and can be irritated from shoes.4
A bursa at the big toe joint is nothing more than trapped inflammatory fluid between the skin and underlying bone. People with bunions are more susceptible to developing a bursa.