Trichorrhexis nodosa is a hair shaft disorder characterised by the formation of white nodes on a hair shaft. Hair breaks off quite easily because of these nodes.
There are two ways that this condition can occur: it can be inherited or acquired through a physical or chemical injury. So, if it’s the latter, you can prevent it by avoiding certain hair practices.
However, not many people know what it is that can lead to the development of trichorrhexis nodosa. It’s even possible to unintentionally worsen the condition.
In this guide, we’ll explore what trichorrhexis nodosa is, its causes, and what you can do about it.
What Is Trichorrhexis Nodosa?
Trichorrhexis nodosa splits the hair into multiple fibres at thick or weak “nodes” on a hair shaft. This condition was first described by Samuel Wilks of Guy’s Hospital in 1852. However, M. Kaposi coined the term for it in 1876.
“Trichorrhexis” means brittleness of hair, and “nodosa” is for the white swellings that appear on the hair. And this happens due to a disruption in the hair cuticle – the outermost layer protecting the shaft from damage.
Once the cuticle cells are lost, the cortical fibres underneath are exposed. They start to separate and fray. Eventually, the hair breaks at the nodes, leaving a thick and round end behind. A close-up of it shows hair bent at these node sites.
A single hair shaft can have more than one or more nodes at the same time. It can depend on how long your hair is. These nodes are scattered at different distances from each other.
While it usually affects the scalp, it can also affect the facial and body hair (e.g. pubes and armpits). Even the slightest trauma can lead to trichorrhexis nodosa if your hair’s already quite weak.
It should be noted that trichorrhexis nodosa is a rare condition. However, among congenital hair shaft abnormalities, it is the most common. It also tends to be more common in African females in its acquired form.
What Are The Different Types of Trichorrhexis Nodosa?
Mainly there are two types of trichorrhexis nodosa, but it has also been described in other health conditions. Let’s take a look at all of them:
Acquired Trichorrhexis Nodosa
Acquired trichorrhexis nodosa, as the name suggests, is when you acquire this condition as a result of mechanical trauma to the shaft. For instance, it can happen due to vigorous over-brushing of hair.
It’s the most common type of trichorrhexis nodosa that tends to affect more African people. It’s because of the kinky structure of their hair, which makes it brittle and weak.
Additionally, certain traumatic hair practices (tight hairstyles and chemical relaxation) tend to be more common among them, which makes their hair more vulnerable.
Other than physical trauma, acquired trichorrhexis nodosa can also happen due to iron, biotin or zinc deficiencies and hormonal imbalances caused by hypothyroidism.
This acquired type is further divided into three subtypes:
Proximal Trichorrhexis Nodosa
Affects the proximal end (towards the scalp) of the hair shaft. Formation of nodes leads to breakage just a few centimetres away from the skin. Scratching, chemical styling, and friction are the usual causes.
Proximal trichorrhexis nodosa is more common in African Americans and may have a genetic basis.
Distal Trichorrhexis Nodosa
When the distal end (away from the scalp) of the hair shaft is affected, it’s known as distal trichorrhexis nodosa. It happens quite a few inches away from the scalp, so it doesn’t leave the hair short.
Hair weathering (deterioration) due to external factors is usually what causes it. And this type of hair shaft disorder is more common in Asians and Caucasians.
Localised Trichorrhexis Nodosa
Localised trichorrhexis nodosa is the rarest type of this disorder. It results in the formation of a (few cm) bald patch on the skin.
According to research published in the International Journal of Trichology, localised trichorrhexis nodosa develops after pruritic dermatoses or frictional alopecia.
Congenital Trichorrhexis Nodosa
Congenital trichorrhexis nodosa refers to when a child is born with this condition due to genetic factors. It can be present at birth or become apparent a few months after.
Research published in the International Journal of Trichology also reports that the congenital type leaves the hair “dry, brittle, and lusterless,” unable to grow long.
Other Health Conditions
While trichorrhexis nodosa can occur on its own, it can also be a part of other health problems, such as:
- Argininosuccinic aciduria
- Netherton syndrome
- Bazex-Dupré-Christol syndrome
- Tay syndrome
- Menkes kinky hair disease
- Ectodermal dysplasia
And, as mentioned above nutritional deficiencies and endocrine gland issues can also cause this problem.
How Do You Know If You Have Trichorrhexis Nodosa?
Symptoms of trichorrhexis nodosa can include:
- Broken hairs of different lengths
- Hair breaks off easily (weak and fragile)
- Presence of glistening white spots
- Dull and uneven hair
- Inability to grow long hair
- Partial hair loss/bald patch
Another sign of this condition is that even a gentle tug will break your hair.
What Causes Trichorrhexis Nodosa?
Trichorrhexis nodosa can be inherited or acquired. In the case of the latter, it can be caused by the following:
- Vigorously rubbing and/or scrubbing hair
- Long-term exposure to UV light
- Aggressive and excessive brushing
- Soaking hair in chlorinated or salt water
- Applying heat
- Tight hairstyles
Research published in JAAD Case Reports also described a case in which a man developed trichorrhexis nodosa in the beard during COVID from mask-wearing.
Among chemical treatments, perming, bleaching, dyeing, and even the use of selenium shampoos can cause trichorrhexis nodosa.
Interestingly, one study published in Dermatologic Surgery reported a case in which a hair transplant patient developed this shaft disorder due to improper graft placement.
Is Trichorrhexis Nodosa Permanent?
It’s possible to reverse trichorrhexis nodosa that’s acquired through physical or chemical trauma.
Keep in mind that the hair above the skin is dead, so it can’t repair itself. You can, however, prevent further damage by limiting trauma.
After two or more years, you should recover completely.
How To Treat Trichorrhexis Nodosa?
Typically, the treatment for trichorrhexis nodosa involves avoiding physical or chemical trauma to the hair.
Your doctor may advise you to change your brushing technique and frequency. You may be asked to use a different brush altogether.
For instance, backcombing and brushes with nylon bristles can cause trauma, according to a study published in the Archives of Dermatology.
Other than that, you’ll be recommended to wear your hair loose and avoid chemical treatments and heat tools.
In a study published in JAAD, researchers describe a scenario in which people increase the usage frequency of heat tools like straighteners to “tame broken or uneven” hair. Of course, that can worsen the problem.
To make the hair less prone to damage, you’ll likely be advised the use of gentle shampoos with conditioners. The latter can be especially useful in reducing friction between shafts. Furthermore, oiling can help.
On the other hand, if trichorrhexis nodosa is the result of an underlying health problem, you need to get treatment for it.
For example, if you have argininosuccinic aciduria, restricting dietary protein and taking arginine supplements might help your hair.
Trichorrhexis nodosa is a rare condition, but it can happen to anyone. Because traumas from hair care can induce it, you might not even think that it will happen to you.
However, once you have it, it can leave your hair quite weak and brittle. The nodes along the hair shaft become breaking points for your hair. This shaft disorder can even cause alopecia.
So, if you think you have this problem, you should make sure to consult a board-certified medical professional. They’ll give you an accurate diagnosis and prepare your treatment plan.
Reviewed and Approved by Dr. Hassan Soueid
Is trichorrhexis nodosa contagious?
On its own, trichorrhexis nodosa can be inherited, but it is not contagious or infectious. It can, however, be acquired through physical and/or chemical trauma.
Can you get trichorrhexis nodosa from dying your hair once?
It may depend on the previous condition of your hair. Even the slightest trauma (which can be caused by dyeing your hair) can cause trichorrhexis if your hair’s already weak.