How a single hair almost caused this baby to lose his thumb.

When her baby boy had a swollen thumb and wouldn’t stop crying, Chinese mother Ms Wang took him to hospital. It was lucky she acted when she did. If she had waited just a day longer, her son’s thumb may have needed to be amputated. Frighteningly, it was all due to a single hair from her head.

Dr Hu Jun Sheng, who treated the baby, suggests mothers should keep their hair short or tied back to stop this kind of injury from happening.

Wang’s two-month-old son was suffering from what’s known as “toe tourniquet” or “hair tourniquet” syndrome. It’s most often seen in young babies, because women tend to shed a lot of hair in the months after childbirth.

What happens is that a single stray hair wraps itself around a finger or toe (or even the penis). It’s thought that as the hair dries out, it shrinks, tightening and sometimes completely disappearing into the skin. Because it’s hard to see, particularly if the hair is blonde and the baby’s skin is fair, parents often don’t spot the problem. All they know is that their baby keeps crying, and has a swollen digit.

In the case of Wang’s baby, he had been crying for four or five days before she brought him into the hospital last Friday. By then, his thumb was close to double its normal size.

The baby's swollen thumb. Image via Jiangsu TV.

According to a report on Jiangsu TV, Dr Hu used a microscope to perform an operation to remove the hair. He says if it had been there for just a day longer, there would have been a risk of tissue death, leading to amputation.

The case is far from a one-off. A 2006 study described it as "a common condition, but relatively under-reported", and said it could sometimes be misdiagnosed by doctors as child abuse.

Last year, a dad in the US took to Facebook to share the story of his baby suffering hair tourniquet. Scott Walker's baby Molly was crying and had a swollen toe, so Molly's mum Jessica, who is a nurse, examined it. She saw the hair and managed to remove it, using a magnifying glass and tweezers.

In 2015, Brisbane mum Evie Canavan went public with her story. Her three-month-old son Kurtis needed surgery under general anaesthetic after hairs were found wrapped around his toes.

Doctors advise that parents should check babies' socks and jumpsuits for loose hairs before putting them on. If babies have a swollen finger or toe, especially with a clear indent, parents should look for hairs, and be prepared to go to the emergency department, if necessary.

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