Bamboo hair, or trichorrhexis nodosa, is a hair shaft abnormality that causes your hair strands to look similar to the knots in a bamboo stalk. Normal, healthy hair strands appear smooth under a microscope. Bamboo hair appears to contain nodules, which are bumps, or evenly spaced ridges. It’s also referred to as trichorrhexis invaginata.
Bamboo hair is a feature of a disease called Netherton’s syndrome. According to Children’s Mercy Hospital and Clinics, most cases of trichorrhexis invaginata are caused by Netherton’s syndrome, which is an inherited condition that causes red, flaky skin all over your body, and allergy problems.
Bamboo hair can affect hair on top of your head, your eyebrows, and your eyelashes.
The symptoms of bamboo hair can include:
- hair that breaks easily
- hair strands that have a knotty appearance
- a loss of eyelashes
- a loss of eyebrows
- sparse hair growth or hair loss pattern
- dry hair
- hair that lacks luster
- spiky hair
- short hair due to consistent breakage
- hair on the eyebrows that resembles matchsticks
Children born with Netherton’s syndrome may have red, flaky skin, and may not develop signs of bamboo hair until after 2 years of age.
An inherited mutated gene called SPINK5 causes bamboo hair. A mutation in this gene causes an abnormal growth process.
Bamboo hair is characterized by a weakness in the cortex, or the center, of your hair strands. Weak spots form at certain points along the strand and nearby harder segments of the cortex press into these weak areas, causing nodules, or ridges, to form. This creates a bumpy appearance on your hair strand and usually causes your hair to break easily.
To diagnose bamboo hair, you’ll need a physical examination. Your doctor will pluck a hair from your scalp to observe it under a microscope.
To diagnose Netherton’s syndrome, your doctor may order a series of DNA tests or a skin biopsy to test for gene mutations. For a skin biopsy, your doctor will remove a small amount of skin tissue for testing in a lab. DNA tests are often used to test the SPINK5 gene for abnormalities.
Since the condition is a direct result of a gene mutation, there’s no known way to prevent the condition. However, there are many types of lotions and ointments you can use to treat bamboo hair. These include:
- emollients and keratolytics to moisturize your skin
- antibiotics for infections in the skin and elsewhere
- topical steroids, which shouldn’t be used on infants
You can minimize hair breakage by ensuring that your hair remains hydrated. You can do this by drinking water regularly and by avoiding the use of alcohol-based hair products. These products cause your hair to dry out, which can worsen the breakage. There are also hair care products aimed at hydrating dry hair.
Avoid the use of chemicals in your hair such as hair relaxers or perms. You shouldn’t use them on damaged hair either. Using these products may result in severe hair loss and cicatricial alopecia, or scarring alopecia. This form of hair loss scars your hair follicles, making future hair growth less likely.
Although the condition can’t be prevented or fully cured because it’s the result of a genetic mutation, there are ways to manage your symptoms by hydrating your hair and healing your skin. Avoiding chemicals that dry your hair and your scalp and using hair care products that hydrate your hair and even ointments and lotions will lessen symptoms. The condition also improves with age even if it’s left untreated.