The four most common causes of runner’s toenails are:
1.Trauma
2.Fungus
3.Eczema
4.Psoriasis
TRAUMA: Trauma may be due to repeated microtrauma, which for runners is usually due to their shoes jamming the ends of their feet. Another source of microtrauma would be hammertoes (toes curled downward), which causes the tips of the toes to get constant pressure whenever one is standing.
Trauma may also be from a sudden, more forceful blow, such as dropping a heavy object on your toes, or badly stubbing your toes.
The majority of runner’s toenails is from trauma. Since there is no disease process or organism, there is no test to help diagnose abnormal toenails caused by trauma. Rather, the diagnosis is made by excluding other causes.
FUNGUS: Fungus toenails are caused by an organism. Usually it spreads to the toenail from the skin when you have athlete’s foot. If you have athlete’s foot and then traumatize the toenail, the fungus can more easily enter under the toenail and take root. Once it gets started, it almost never goes away on its own. If one has chronic athlete’s foot, or a toenail infected with fungus, the fungus is more likely to eventually spread to other toenails. Exposure to the organism comes from using public bathing facilities, swimming pools, and family members who have it.
There are different tests that can detect the organism. The tests are not perfect, so if the first one is negative (no organism), your doctor may wish to repeat the test. I advise against treating for fungus toenails without a positive test, since many toenails that look like they are infected with fungus are not.
ECZEMA: Eczema is a chronic inflammatory condition and usually also affects the skin. Therefore, if one has eczema, affected toenails may also be due to eczema, although fungus can also be present.
PSORIASIS: Similarly, psoriasis affects primarily the skin, but in a small portion of cases it may affect toenails. Just as in someone who has eczema, if one has psoriasis, fungus may also be present.
The diagnosis can get even more confusing when more than one cause is present. If one’s abnormal toenails are caused by both trauma and fungus, how much of the abnormal appearance is due to each?
There is no way to know prior to treatment. Unfortunately, after treating and (hopefully) eliminating the fungus, the toenail may still not look completely normal if it has also been significantly traumatized (physically—not emotionally!).
THE TREATMENT
If trauma is the cause, did it temporarily or permanently damage the toenail? If the cause was repeated micro-trauma, it is possible that eliminating the cause (such as ill-fitting shoes) may lead to the nail improving.
However, if the trauma damaged the root of the nail (such as having dropped a heavy object on your toe several years ago), the root is permanently scarred, and a normal nail is no longer possible. In the latter case, no treatment is appropriate, unless the nail is causing discomfort.
If the nail is causing discomfort despite having proper fitting shoes, either the edge or the entire toenail can be removed temporarily or permanently. Usually permanent removal is indicated. If the nail is ingrown, removal of only the edge(s) may suffice.
If fungus is the cause (which almost always should be proven via testing prior to beginning treatment), the organism can usually be eliminated. Be forewarned, these organisms are stubborn once they are embedded within the toenail, so the treatment takes several months to produce a normal nail.
Topical Medications have a low rate of success, but are relatively safe and easy. Topical medication is more likely to succeed if the fungus involves only the end of the nail rather than most or all of it. If the entire nail is involved, topical medication rarely works.
Oral Medication had a well-deserved poor reputation for many years because they had side effects and were successful less than half the time. However, some newer medications are safer and successful (when used properly) about two-thirds of the time.
Even though the newer medications are safer, I still recommend lab tests before and during the course of treatment to make sure they are not causing a problem.
If the medication leads to abnormal lab tests (usually involving your liver), it would then be stopped. Based upon many studies, the lab values of otherwise healthy patients almost always return to normal.
In order not to invite trouble, it is important to share with your doctor any factors that might already be stressing your liver, such as other medications, hepatitis, drug use, and chronic overuse of alcohol.
A reminder that if the abnormal toenail is due to both trauma and fungus, eliminating the fungus may lead to improvement, but not a completely normal nail. In this case, is treatment worthwhile? Perhaps so, since not only might the appearance of the nail(s) improve, one is (hopefully) preventing the condition from getting worse and/or spreading.
I do not treat my patients who have abnormal toenails due to psoriasis or eczema with medication since these conditions are chronic. Therefore, I only treat them with partial or total removal of the nail, and only in those cases when the nail is causing discomfort or ingrown nail infections.
PREVENTION
If one’s shoes do not fit well, the toenails may not improve regardless of the etiology and/or treatment.
If one has chronic athlete’s foot, even though it may not bother you (often the case), it should still be eliminated so that it does not spread to toenails.
People who have had fungus toenails are more likely to get the condition again.
I believe there are two main reasons:
1.Your immune system might be great against most foreign invaders, but simply not do a very good job against fungi.
2.The original source of exposure may still be present, such as public shower facilities (wear thongs), a spouse (change the spouse???), or returning to the same shoes without disinfecting them.
Although antifungal powder is very poor at eliminating the organism once it gets started, keeping your shoes dusted with antifungal powder will make it more difficult for the organism to take root.
Hey, those runner’s toenails can be thick, and weigh more. How much faster might you be without them?
Dr. Goldstein is Board Certified in Podiatric Surgery, Podiatric Orthopedics, and in Podiatric Medicine. Dr. Goldstein practices in Portland, Oregon. He has been running for many years, although sometimes he rests.
