We all know that people are different from each other. Your Great Aunt Ophelia is nothing like your teenage son, and your boss bears little resemblance to the kid you had a crush on in second grade. But we all have things in common, otherwise we wouldn't be human. Like the number of bones in our body. We've all got 206, right? Well...not necessarily. Another definition of humanity must be found, since some people (who are undeniably Homo sapiens) have some extra bones hanging around. This isn't an indicator that they're the next step in evolution, nor that they've come from another planet and are thus imbued with special powers. Sometimes people just have extra bones.
These extra bones, called accessory ossicles, may show up in your foot. They usually occur because a small portion of bone (a bone growth center) fails to fuse together with the rest of the bone mass during childhood, when cartilage is turning to bone. Sometimes, the condition may be caused by an old trauma (aka injury) as well.
Extra bones may show up in numerous places in the foot, although they're most commonly found in a few spots. These include the accessory navicular bone (also called Os Tibiale Externum or Os Naviculare) which occurs on the inside part of the middle of your foot, the Os Trigonum which shows up right behind the Talus (ankle bone), the Os Peroneum which is located next to the Cuboid bone (on the outside of the foot near the heel), and the Os Vesalinum which also occurs on the outside of the foot, near the base of the fifth metatarsal (the long bone that, along with the other four metatarsals, makes up the midfoot).
Symptoms
Having extra bones isn't always a big deal (although it could make for an interesting conversation starter at dinner), since these accessory ossicles often don't cause any symptoms at all. In fact, the first time you become aware of them may be when you get an X-ray for something completely unrelated.
Unfortunately, despite their usual good behavior, these bones do occasionally cause trouble. They may raise a bony bump under your skin that rubs on the inside of shoes or makes it painful to bear weight. This prominence may become reddened or swollen. Extra bones can also interfere with the proper function (or be a symptom of improper structure) of the tendons of your foot, which can lead to soreness or throbbing pain. Occasionally, these extra bones may keep other bones from moving properly, and thus cause joint pain and a reduction in joint motion.
Diagnosis
Your podiatrist is well aware that some people have extra bones in their feet, and won't be fazed when you go in with symptoms (or if the bone simply shows up on an unrelated X-ray). In order to diagnose the condition, the podiatrist may inquire about symptoms you've experienced, might press on the bony prominence to determine if there's any discomfort, and may test the motion of your joints, your muscle strength, and check the way you walk. In order to make a definite diagnosis, X-rays or other imaging methods are often suggested.
Treatment
Fortunately, there are many ways to treat this condition that do not involve surgery. (And some of you may secretly kind of want to keep that extra bone.) They usually involve reducing inflammation by using the RICE method (Rest, Ice, Compression, and Elevation), medication (such as ibuprofen or steroidal treatments), physical therapy (if muscle strength is an issue), and orthotics (which can reduce pressure on the bony prominence and help out any associated ailing tendons). Casts are sometimes also used to rest the foot and allow inflammation time to die down.
If these treatments don't help much, then surgery might be a good option. (You'll lose that cool extra bone, but you'll be able to walk more easily.) Surgery usually involves removing the bone, and possibly correcting any problems with associated tendons.
Whatever the treatment, you'll always know that you have (or had) a little extra something about you that isn't just run-of-the-mill. You are, at least slightly, just a little superhuman. Sort of.
