The ends of your bones are covered in smooth cartilage. When this cartilage is damaged, the bones can rub together and cause pain. The rubbing can create extra bone, called a bone spur. The bone spur can prevent the big toe from moving like it should, giving you hallux rigidus or big toe arthritis. 

The surgeon will make small cuts into your toe and remove bone. Removing bone gives more space in the toe and allows the toe to bend. 

After the surgery you may have to wear a boot and may not be able to do normal activities for a few months while your foot heals.