Your spine has 26 bones, and here are 26 facts to remember about it to keep yourself healthy – and pain free
- The vertebral column is vital to our health but its health is often overlooked
- Neck injuries are on the rise because of texting
Are you sitting slouched at your seat as you read this?
While you are definitely not alone in this increasingly common habit, understanding how your spine works might help you straighten up a little.
The spine is a set of bones stretching from the pelvis to the head, which support the upper body, help us stand and give us mobility.
It also houses and protects the spinal cord, which is part of the organ that makes up the nervous system.
All of this makes it clear that the spine is really important.
However, there is a lot you probably do not know about your spine and how you can keep it healthy.
To that end we have come up with 26 intriguing facts about the spine with the help of medical experts at the Hong Kong Adventist Hospital – Stubbs Road.
Why 26? Because this is the number of bones in the average adult’s spinal column – 24 presacral vertebrae, the sacrum and the coccyx.
Dr Clarence Leung, clinical director of the Minimally Invasive Spine Surgery Centre and specialist in neurosurgery at the hospital, says understanding often-overlooked facts about the spine is the first step to improving spinal health and reducing pain and injury.
“Most people don’t realise the complexity of the spine,” Leung says.
Combine this with modern-day sedentary habits and/or exercising the wrong way – or exercising too much at weekends after sitting down all week – and you have a multitude of routes to spinal injury.
Yet this is not news to millions of people around the world who are suffering from some kind of back or neck pain.
The American Chiropractic Association says up to 80 per cent of the US population will suffer from back pain at some point in their lives.
A study by the University of Hong Kong shows that seven out of 10 Hong Kong adults suffer from disc degeneration – a primary cause of lower back pain and disability.
Modern-day practices have led to spinal issues such as sciatica or slipped discs, which are a problem for individuals of all ages.
Long hours spent hunched over computers while working or studying, or craning your neck forwards while texting on your smartphone – and the subsequent inactivity – have spurred the Hong Kong Chiropractors’ Association to create an education initiative called Straighten Up Hong Kong.
“Increasingly in this technological age, individuals are experiencing greater levels of spinal discomfort and disability related to stress and poor posture,” it says.
“Many people commonly work and play in cramped, awkward, slouched postures.
“The resulting back pain compromises the quality of our lives [and] results in tremendous costs related to health care fees and diminished individual income and productivity.”
Slouching does not always cause pain, but over time sitting in this position can put a strain on sore muscles and soft tissues – and hurt your spine.
So maintaining a good posture when sitting or standing is important.
To help us fully understand the spine and the vital role it plays it our general health and well-being Leung and other international medical specialists at the hospital have prepared 26 fascinating spinal facts.
26 facts about your spine
1. It’s flexible.
The spine is so flexible it can curve to form two-thirds of a circle.
2. How many joints?
The spine contains more than 100 joints.
3. Just like a giraffe.
Both giraffes and humans have seven vertebrae in their necks.
4. How many neurons?
The spinal cord contains around 13.5 million neurons.
5. How long is the spine?
The average length of a woman’s vertebral column is 61 centimetres (24 inches); in men it is about 71 centimetres.
6. Great support.
The top part of your spine supports your head, which weighs between 4.5kg (10 pounds) and 5kg. The lower part holds most of your body’s weight.
7. There are 120 muscles in the spine.
These muscles play an important role in maintaining the three natural curves of your spine in neutral alignment.
This, in turn, keeps your spine in balance and protects the tissue around it.
If your spine is out of alignment, you will suffer from muscle fatigue, which, after a long day spent with poor posture in a sedentary position, often leads to chronic pain at night.
8. How many vertebrae?
We are born with 33 individual vertebrae, some of which fuse together to form the sacrum and the coccyx, leaving us with 24 presacral vertebrae when we reach adulthood.
9. The shape of the letter ‘S’.
From the side, your spine looks like the letter “S” – shaped in such a way that the curves of the spine can support your body weight.
10. How thick in the spinal cord?
The spinal cord is between 1 centimetre and 1.5 centimetres thick and it reaches its full length when we are four years old.
11. ‘Super’ strength under pressure.
The spine is so strong it can support hundreds of kg worth of pressure.
12. ‘Spongy’ cartilage in the spine.
More than a quarter of the spine’s total length consists of cartilage – the spongelike substance that separates one vertebral disc from the next.
13. Space travel ‘makes you grow’.
Astronauts returning from space can be up to 3 per cent taller, gaining as much as 2 inches (5 centimetres) in height because – so the theory goes – vertebrae normally compressed by Earth’s gravity stretch out in microgravity.
Studies have shown that astronauts’ spines typically compress as soon as they enter our atmosphere and are subject to normal gravity.
Generally, they return to the normal height within 10 days of arriving back on Earth.
14. You are very slightly taller first thing in the morning.
Over the course of each day, the weight of your body puts increasing pressure on the intervertebral discs that provide cushioning between the bones in your neck and back, causing the discs to compress and reduce the length of your spine.
15. ‘Messages’ from the spinal cord.
Recent studies have shown that the spinal cord is able to operate independently of the brain when it comes to the early stages of learning new motor skills.
The spinal cord can, therefore, send important messages directly to the muscles without the input of the brain.
16. Disc degeneration.
A University of Hong Kong study in 2012 shows that seven out of 10 Hong Kong adults suffer from disc degeneration, which is one of the major causes of lower back pain and disability.
17. Lumbar complaints.
Up to 70 per cent of the complaints Leung deals with relate to the lumbar (or lower back) region.
The remaining 30 per cent of cases relate to pain around the neck or cervical spine area. Most of his patients also come to him with muscle-related back problems.
18. Vertebral fractures.
The International Osteoporosis Foundation says the prevalence of vertebral fractures in Hong Kong is estimated at 30 per cent in women and 17 per cent in men between the ages of 70 and 79.
19. Use of smartphones is linked to injuries
Frequent use of mobile phone – with people spending long periods with their heads looking down as they read and send texts – is leading to a rise in the number of neck injuries.
Neck problems are likely to catch up with lumbar spine issues in the near future.
20. The spine has an amazing memory.
Postural improvement and stretching are the first line of defence – and the best way to keep a spine flexible as we age, as well as after surgery.
21. Stop smoking.
As well as reducing bone density, smoking decreases blood flow throughout the body, including in the spine, depriving your spinal tissue of vital oxygen and nutrients and making spinal discs less cushioned.
Studies also show that smoking can considerably slow down the healing time – making it harder to recover from spinal injuries or surgery.
22. Spinal cord injuries.
The higher up the spinal cord an injury occurs, the more damage is caused.
Someone with an injury in the neck might suffer from paralysis in all four limbs, speech might be impaired, and they might not be able to breathe on their own.
An injury lower on the spinal cord could mean loss of movement in the legs and chest.
23. Most common causes of injuries.
Car accidents and falls are the most common causes of spinal cord injury in Asia.
However, studies also show that in some Asian countries, war wounds play a significant role in spinal cord injury.
24. The spine’s flexibility is good ... and bad.
Although the spine’s flexibility is what keeps us mobile, it also makes it susceptible to problems.
It can bend the wrong way, which presents itself as scoliosis; it can be severed as a result of a spinal cord injury; often a symptom of multiple sclerosis, the coating over nerves – called the myelin sheath – can deteriorate, leading to chronic pain; tumours can compress the nerves, leading to infection and abscesses.
25. You need strong core muscles to support your spine.
Leung says that running or cycling will develop only the visible, top layer of muscles, rather than working the deep core muscles.
Consider taking up Pilates – a system of exercises using special apparatus, designed to improve physical strength, flexibility, and posture, and enhance mental awareness – to help strengthen your core.
26. Sleeping on your back puts extra pressure on your spine.
You can counteract this by placing a couple of pillows under your knees.
Alternatively, consider sleeping on your side with a pillow between your knees, or try lying on your side in the fetal position, tucking your knees towards your chest and your chest towards your knees.
One simple way to keep your spine healthy is to get up from your desk regularly and move around.
Leung says: “People need to stretch regularly to keep their spines flexible.”