Have you ever noticed a small vertical line running down one of your fingernails and wondered what could be the reason? Could it be something serious? In this article, we will take a look at the reasons behind this black line on nail. While most of the times the black lines on nail or any other form of discoloration does not indicate any serious underlying issues but it is still a good idea to get it looked at if the problem persists for more than a few days, a week at most. We will also look at how this black line on nail can be a result of splinter hemorrhages.

Could a Black Line on Nail Mean Splinter Hemorrhages?

black line on nails - Splinter Hemorrhages

Splinter Hemorrhages can be attributed to a condition in which small blemishes appear on the nails which could indicate that the area in which these blemishes or spots appeared have suffered some sort of trauma. However, in some cases, this blemish or black line on nail could mean there’s something more serious that could be causing it.

Splinter Hemorrhages Symptoms

One of the most easily noticed symptoms of splinter hemorrhages is discoloration of the nails due to a bleeding blood vessel running below the nail. Other symptoms are blemishes or dark spots or even vertical black line on nail. This kind of discoloration or blemish cannot lead to any sort of discomfort in the area of occurrence with the exception of the cases where you may have suffered some injury or trauma.

Causes of Splinter Hemorrhages

There are two main possibilities under which splinter hemorrhages can occur, one is due to some external factors such as injuries and the second case where the hemorrhages can be caused by some underlying medical condition. Let’s take a look at top seven underlying causes of splinter hemorrhages.

1. Trauma To The Nail

The most common cause of splinter hemorrhage is a trauma suffered to the nails which exhibit black lines.

  • A trauma to the nail can be a painful experience but is certainly not a matter of much concern.
  • The black line on nail due to stubbing usually goes away within a few days of the trauma suffered and is healed back to its normal color.

2. Fungal Infections

Although a fungal infection comes in the acute spectrum of diseases it can still be one of the underlying conditions that cause black line on nail. The likely causes of fungal infections are as follows.

  • If you have come in contact with someone with the condition.
  • if you are actively participating in sports in which wearing shoes is a necessity for a prolonged period such as basketball, football or tennis.
  • If you have suffered any injuries to the nail.

3. Bacterial Endocarditis

Bacterial Endocarditis is also known as Infective Endocarditis (or IE) is a condition wherein bacteria starts accumulating in the linings of the heart.

  • The accumulation of bacteria in the heart lining sometimes leak out and circulate to other parts of the body such as the nails, and hence the appearance of the black line on nail which happens because of splinter hemorrhages.
  • Endocarditis, especially in patients with pre-existing heart conditions can lead to serious problems with the body’s immune system. A compromised immune system may lead to deteriorated health and could ultimately lead to fatality even with external medications.

4. Vasculitis

Another health condition which can be the underlying cause of splinter hemorrhages and thus the black line on nail is vasculitis.

  • Vasculitis is a disease which causes alterations to the blood vessels such as either the vessels can grow thick, weak or narrow and hinder blood flow through the body.
  • Due to the hindered flow of blood caused by vasculitis, in some cases blemish or black line on nail can occur which is a symptom of splinter hemorrhages.
  • Vasculitis although has very effective treatments but there is no permanent cure for this disease.

5. Diabetes

Diabetes, as mentioned previously can also be the underlying cause of splinter hemorrhages. There are a total of four types of diabetes but we only need to be concerned about Type 2 Diabetes.

  • Diabetes is a medical condition in which the body is not able to control or process the sugar or glucose to convert it into energy.
  • Since high amounts of glucose and sugar remain unprocessed, they start damaging the blood vessels and hence one can the splinter hemorrhages in the form of a black line on nail.

6. High Cholesterol Levels

Cholesterol is a biosynthetic component which constitutes the structural walls of the cellular membranes. High cholesterol levels are usually caused because of unhealthy eating habits.

  • High Cholesterol means that unwanted fats get deposited in the blood vessels, thickening them in a way which causes problems with the blood flow.
  • These blood flow problems can result in very serious conditions such as coronary heart disease, heart attacks and strokes.
  • The problem with the blood flow also results in splinter hemorrhages in some cases.

Also, read about: Foods To Avoid With High Blood Pressure.

7. Melanoma

Melanoma is one of the most life-threatening types of cancer in which abnormal developments can occur on the skin caused by some sort of ultraviolet radiation such as too much exposure to sunlight.

  • Melanoma is a skin cancer in which certain area on the skin (usually anywhere around the torso or legs) can develop some deformity like a red or a black spot.
  • In dark-skinned people, the occurrence of melanoma is very rare but in those rare cases, it usually occurs in the form of a black line on nail of toes or fingers.

Also, read about: Athlete’s Foot Meaning, Causes & Treatment.

The prerequisite for a diagnosis is to determine if the splinter occurred due to any injuries to the nails or the general area around it. If such is the case then a consultation with a doctor is rarely recommended. On the off chance that there was no history of injury or trauma to the nails then one should immediately seek medical help.

If a doctor has determined that injury or trauma is the cause of splinter hemorrhages, then you may be suggested to do some or all of the following tests.

  • Blood Culture
    A Blood culture, in this case, will be conducted to check for the presence of fungi in the blood.
  • Erythrocyte Sedimentation
    This test is conducted to determine if your body is suffering from any inflammation.
  • Chest X-Ray and Echocardiogram
    These tests need to be conducted if the doctor suspects that the hemorrhages are occurring due to bacterial endocarditis.
  • Biopsy
    Finally, a biopsy is adviced when there is a possibility where the underlying cause could be melanoma.

Is Splinter Hemorrhages Treatable?

In most cases, you can get rid of the black line on the nail ergo, the splinter hemorrhages by pretty much letting it heal on its own over time. However, in other rare cases, medication recommended by the doctor will aid in the treatment.

  • In case of injuries and traumas, the best treatment is to just let the nail grow out and heal on its own.
  • In case the reason for the hemorrhage is fungal infection then the doctors may recommend some antifungal medications.
  • In case the cause of the hemorrhage is an underlying some other medical condition then it is bound to go away once that condition has been treated.


The black line on nail is usually caused due to splinter hemorrhages which depending on the underlying cause can be treated and rarely poses any fatal threats. Usually, this is a harmless health condition but can be a sign of a serious problem too. Generally, it grows if you face any nail trauma. But if you experience such a symptom without any traumatic condition, you should possibly see a doctor for a thorough diagnosis.

If you experience any problem-related to skin or nail, get in touch with the Best Dermatologist in India.

For more information and free personalized guidance, talk to Credihealth Medical Experts today.

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