Yellow, possibly fungal, nails are one of the most common complaints that show up at a podiatry office.  There are many misconceptions about fungal nails and I'd like to take you on a quick tour of my approach to ugly, yellow, and often dystrophic nails. 

First of all, many patients come in complaining of a fungal infection because their toenails look yellow, chunky, or like they're about to fall off.  The misnomer is that all yellow nails are infected which is often not the case.  The most common cause of yellow dystrophic nails is actually what we call micro trauma.

Micro Trauma to the nail unit is repetitive banging or force on the nail.  This repetitive trauma to the nail will over time cause a callus to form under the nail.  Normally when your skin forms a callus the excess skin will eventually be sloughed off.  When the callus is under the nail the skin is stuck and pushes up on the nail.  This excess skin tissue is what causes the nail to appear yellow and often raises the nail unit up eventually causing the nail to fall off. 

So, when a young patient comes in that has recently started training for a marathon, my mind is thinking micro trauma, not infection.  The micro trauma generally occurs in athletes, especially runners with tight shoes that don't allow enough space for the toes to slide forward upon impact.  Instead the toes are slamming into the forward aspect of the shoe, causing damage.  So, I tell my runners to bring in their shoes so I can take a look and see if they are fitting correctly.  If they have micro trauma then nine times out of ten their shoes are too small. 

The second half of the story is unfortunately, fungus.

Remember that callus which formed under the nail?  Well that callus is mostly keratin, the main component of skin.  Anyone want to guess what fungal organisms like T. Rubrum like to feed on? That's right, keratin.  The micro trauma will cause your nails to become yellow and ugly and can also provide a nice cozy home for fungal organisms to thrive in.  Once that fungus gets in there, it can be very difficult to get rid of.

If you have any questions about your shoe gear, feet, or nails, make an appointment with your local podiatrist at Affiliated Foot and Ankle Care in Edison and Monroe NJ today.

By Nrupa Shah