Did you know you can have an extra bone in your foot?
The human body has 640 muscles and 206 bones…approximately. I know this in part because I head to learn every one of them in Gross Anatomy class. But did you know that you can have an extra bone in your foot? The average human foot has 26 bones in it, but some people are born with (meaning they are congenital) an accessory bone or two. The three most common accessory bones are the os trigonum (behind the ankle), os tibiale externum (also known as the accessory navicular for the inside of the foot), and os peroneum and os vesalianum (which are both located on the outside aspect of the midfoot).
These extra bones usually aren’t and issue, and most people don’t even know they have them, and can live a full and active lifetime without ever having the accessory bones addressed. On occasion these accessory bones could get flared up and inflamed or rub in your shoes. It is at this point when most people start complaining of pain in the area of the accessory bones. X-rays will often reveal the accessory bones, and they can sometimes even be mistaken for fractures. In some cases, the bones get in between the joints and cause some people to develop arthritis in their foot, which I have seen lead to surgery to remove the accessory bone, remove the plate of arthritis that formed, and then screws inserted for stability of the surgically repaired ankle.
ONE THING I LEARNED TODAY:
Some people are born with extra bones in their body, and these congenital birth differences for the most part are harmless and people don’t even know they have them. If it becomes a persistent problem, it should be addressed. Physical therapy could be a good option, but if that doesn’t help, an orthopedic (bone, muscle and joint doctor) or podiatrist (foot specialist) may be helpful.