Why do people get cervical spondylosis? It starts with the weight of a person's head.
In the Spring and Autumn Period and the Warring States Period, it was not difficult to know how heavy a person's head was. But in today's highly developed civilization, it is difficult to know how heavy a person's head is. But this is not difficult for the gods from all walks of life. People from all walks of life in the fields of mathematics, physics, and medicine have had heated discussions and studies on this issue.
The first thing that comes to mind is to put your head directly on the scale, try to relax your neck muscles, and the weight of the scale is roughly the weight of the skull. But this method is too incorrect: because it is difficult for the neck to be completely relaxed, and the neck also has weight, this part of the weight is included.
Some people in the medical community have thought that there is a gap between the cervical vertebrae of people, and this can be used to measure the weight of a living person's head: tie people's feet to ropes and hang people upside down with pulleys, and then slowly descend until the scalp just touches the scale, and then start X-ray and other imaging equipment to observe the distance between the top of the cervical vertebrae and the skull in real time. Continue to lower your body slowly, and the moment the distance between the top of the cervical spine and the skull begins to shorten, the scale will read the weight of your skull.
Some people in mathematics have proposed the use of the lever principle: first the whole person lies flat on one side of the lever, the head is flat, and then a weight is placed on the other side of the lever until the lever is balanced. Then lift your head up and lean as much as you can on your chest. Because the center of gravity changes when the head is bent, the lever must be tilted, and then slowly move the weight on the other side to rebalance the lever. By measuring the distance of the weight and the distance of the head before and after bending, the weight of the skull can be calculated by combining the weight of the human body with the principle of levers.
Someone in the physics community came up with the idea of using Archimedes' law of buoyancy, and the method is relatively simple: completely submerge the head in a basin filled with water, and the volume of the overflowing water is the volume of the skull. Then submerge the whole person into a basin filled with water, and the volume of the overflowing water is the volume of the human body. Then based on the weight of the human body, the weight of the skull can be calculated. Of course, this method is not perfect, because the density of the skull is not exactly the same as the density of the whole body.
In short, there is no perfect way to measure the weight of a living human skull, but after years of argumentation by the scientific community, it is roughly concluded that the weight of the skull is 4-5.5 kilograms.
That is to say, except when a person sleeps flat, the weight of the cervical spine is at least 4 kg or more at all times.
Look down at your phone
Your neck is equivalent to
Hung a bag of 50 catties of rice
We can think of our cervical spine as a spring. In fact, when we look down at our phones or do other work, the force on this spring far exceeds the weight of the skull itself.
Some studies have found that taking a 5-kilogram head as an example, when he stands or sits upright, the spring of the cervical spine is only subjected to downward pressure from the skull, that is, the cervical spine bears 5 kilograms. Equivalent to the weight of a watermelon on top of your head.
When he bowed his head slightly at 15 degrees, the force on his cervical spine was 12 kg. It is equivalent to the weight of a kindergarten child on his head.
When the head is low to 30 degrees, the cervical spine bears 18 kilograms, which is equivalent to a case of beer pressing on the head.
When we bury our heads in watching mobile phones, playing games and watching short videos, the amplitude of bowing our heads may reach 60 degrees, and the force on the cervical spine is equivalent to 27 kilograms, which is equivalent to hanging a bag of 50 catties of rice around our neck.
Just imagine, if a spring hangs such a heavy thing for a long time, it will inevitably fail after a long time.
Dr. Tian Fei of the Department of Orthopedics of Hangzhou First People's Hospital said that the spine is an irregular bony structure: the front is a disc-shaped vertebral body, and the upper and lower vertebral bodies are connected by intervertebral discs and ligaments, and the intervertebral disc is an elastic fibrous tissue that can play a good role in cushioning, and there are bony joints in the back. Among them, the cervical spine is more complex and fragile, it is composed of seven segments, surrounding the cervical spinal cord and its meninges. It is connected by intervertebral discs and ligaments, forming a physiological curvature of lordosis.
Therefore, when the head is kept down for a long time, the anterior intervertebral disc will bear a lot of pressure between the vertebral bodies, and the long-term compression will gradually degenerate, reduce elasticity, and protrude to the periphery, which is what we call intervertebral disc herniation, and the protrusion backward will compress the spinal cord and nerve roots. The muscles and ligaments behind the neck and shoulder will also bear greater tension, causing strain of muscles and ligaments, causing aseptic inflammation and stimulating peripheral autonomic nerves, and then causing neck and shoulder discomfort, and even dizziness and nausea.
When the neck is too much to handle, there will be severe muscle aches, stiffness, spinal nerve compression, and the longer it lasts, the worse it gets.
Lean back on the bedside or couch and play with your phone and read a book
It hurts the cervical spine more than sitting and looking down at the phone
Professor Qian Yu, vice president of Zhejiang Provincial Hospital of Traditional Chinese Medicine and an expert in spine diseases, said that the posture of leaning on the head of the bed or leaning on the sofa to play with the mobile phone, because the neck is used as the fulcrum to lean on the head of the bed or the sofa, the cervical spine will be maintained in a forward flexion position, that is, the cervical spine is in the position of the reverse arch, and the shape is similar to the right half of the bracket")", while our normal cervical spine shape is C-shaped, which is equivalent to the left half of the bracket "(]. Maintaining the posture of cervical spine reverse-arch for a long time will cause the cervical spine to deviate seriously from the normal physiological curvature, which will lead to cervical spondylosis in the long run.
Not only that, leaning on the headboard or leaning on the sofa to play with mobile phones for a long time will also accelerate the degeneration of the cervical intervertebral disc, which will lead to narrowing of the intervertebral space, relaxation of the joint capsule and ligaments, and decreased stability of the spine during spinal activities, which in turn will cause degeneration, hyperplasia, and calcification of the vertebral body, facet joints, hook joints, anterior and posterior longitudinal ligaments, ligamentum flavum and collar ligaments. It can be said that leaning on the bedside or sofa and playing with a mobile phone to read a book is more harmful than bowing your head to play with your mobile phone and reading a book.
Professor Qian Yu said that in the past, most of the patients with cervical spondylosis encountered in the outpatient clinic were teachers, accountants, and IT practitioners. In recent years, the professionalization of patients with cervical spondylosis has become less obvious. Due to the widespread use of smart communication devices such as mobile phones, the trend of younger cervical spondylosis is indeed becoming more and more obvious, many young people bow their heads to play with mobile phones for several hours, in such a posture, the cervical spine is not only bent forward, but also suspended, which will greatly increase the pressure on the cervical spine.
in everyday life
How can we protect the cervical spine?
Professor Qian Yu gave four professional suggestions——
1. Avoid sedentary lifestyles. Every time you learn to Xi and work for about 45 minutes, you need to get up and move for 10 minutes, get up and move your body and cervical spine, change the rhythm of your body, relieve the tense muscles, and give the cervical spine a respite.
2. Insist on cervical spine exercises. It has been reported that "shaking head exercise" and "rice word exercise" are good for the prevention and treatment of cervical spondylosis. In fact, whether to take these two exercise methods depends on the stability of the cervical spine, the hyperostosis of the cervical spine, the change of the cervical spine curve, and the blood supply of the vertebral artery.
If the cervical spine is unstable, bone hyperplasia is obvious, or the vertebral artery is insufficient, do not turn the head vigorously. For those who are not suitable for the "rice" exercise, you can try the posterior neck muscle exercise: take a towel and put it on the back of your head, pull the towel forward with both hands, and push the back of your head back for 15-20 seconds. Generally, 12 pieces per group, 3 sets a day is better.
3. In autumn and winter, when the weather is cold, the blood vessels are constricted, and the blood circulation is not smooth, you can use scarves and sweaters to keep out the cold, or local hot compresses, "go to the cold and warm, and no skin leakage" to protect the cervical spine.
4. Self-massage, acupoint kneading. Patients with cervical spondylosis can also improve their neck discomfort through simple self-massage, such as massaging and kneading with both hands on the back of the neck, and repeated lifting and pinching with one hand on the back of the neck. Tai Chi and Baduanjin exercises can also play a role in relaxing the muscles and activating the body, smoothing the qi and blood, regulating the emotions, and strengthening the muscles and bones. You can rub the Fengchi acupoint, the shoulder well acupoint, the Hegu acupoint and the Houxi acupoint on both sides for 3-5 minutes each, and the local soreness can be tolerated.
Tian Fei reminded that cervical spondylosis should be prevented at an early stage. Although generally speaking, the cervical spine does not age until after the age of 20, if you do not pay attention to protection, the age of onset will be greatly earlier.
Therefore, for the student group, the protection of the cervical spine should start from a young age. Avoid sitting at the desk for a long time, maintain a correct posture when doing homework, choose a table and chair with the right height, and adjust the height of the table and chair in time according to the child's height change.
In addition, the most important thing is to avoid looking at electronics for long periods of time, and even when using them, maintain a correct sitting posture and try to keep the screen height and eye level.
Usually pay attention to avoid cold in the cervical spine, rapid and repetitive exercise, you can do cervical spine exercises regularly, exercise the muscles behind the neck, and enhance the stability of the cervical spine. The cervical spine physiotherapy instrument can also be used appropriately to relax the muscles and ligaments.
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