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Old 7th May 2020, 16:53   #16
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Default Re: Whiplash protection vs Chronic neck pain

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Originally Posted by Shreyans_Jain View Post

Seats are essentially the same as the Jazz pictured above. See the difference. Especially the upper back cushioning.
Seems the back portion of the head restraint in the city is still relatively comfortable.

Here's how the flipped head restraint looks like in my polo:

Whiplash protection vs Chronic neck pain-seatflipped.jpeg

It doesn't push the head ahead anymore and reduces the pain, but it's not exactly comfortable and the angle seems rather sharp to rest your head or even prevent whiplash injuries effectively.

So I tried the rod bending method shown in the video, and basically it does not work as intended. Turns out that the rods of the head restraint are mounted in plastic fixtures. So any attempt to bend the rods from the base essentially deform the plastic, and it comes back to its original shape immediately after the bending load is removed, leaving the head restraint exactly as it always was. I guess any attempt at bending the rods will need to bend them away from this plastic. And that's tricky too because the rods are hollow and could easily pinch when bent.

So now I'm looking at using some thin padding in the highlighted area below (just below the head restraint) to reduce the angle between the back and the neck. Not sure if that's going to work, but will update here.

Whiplash protection vs Chronic neck pain-potential-padding.jpg
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Old 15th May 2020, 15:30   #17
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Default Re: Whiplash protection vs Chronic neck pain

Faced a similar situation in elite i20. Tried using car neck pillows. Neck pain has been alleviated to a great extent.

Experts, any side effects of using the same?
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Old 15th May 2020, 20:29   #18
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Default Re: Whiplash protection vs Chronic neck pain

The head rests are not positioned to push your head forward, they are meant to keep it in neutral. If your backrest is positioned properly, the head rest of any modern car should not touch/push your head forward. If it does, your backrest position is probably not proper/ideal (most probably is too upright). It is shockingly common to see bad posture of drivers when driving here and in the west as well. Unfortunately people get so used to their preferred position however less than ideal it may be, that any change seems foreign to them. People who have the above problem I would suggest, try to adjust your backrest rather than fiddle with the head rests. Also, I wouldn't suggest reversing them as the metal rods are positioned more posteriorly in the headrests without much padding and if you do have a shunt they may actually injure your head.
The Passat actually has a head rest that you can move front/back as per your comfort but haven't seen too many other cars with this.
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Old 15th May 2020, 21:34   #19
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Default Re: Whiplash protection vs Chronic neck pain

Sorry to add another post, but forgot to add this in above post. Also the bulging portion of the head rest is supposed to be in the region of the curve of the neck and not against the back of the head. This is to accommodate the natural curve of the cervical spine (lordosis). If your head rest positioned too high, it will rest against your occiput (which is the point of most curvature of your skull) and push your head ahead. This is a problem for short drivers and can cause neck pain and I would suggest add a seat cushion or something to raise your height a bit (keep the headrest in lowermost position) so the head rest sits in the ideal position.
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Old 16th May 2020, 17:34   #20
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Default Re: Whiplash protection vs Chronic neck pain

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Originally Posted by Amsdoc View Post
Sorry to add another post, but forgot to add this in above post. Also the bulging portion of the head rest is supposed to be in the region of the curve of the neck and not against the back of the head. This is to accommodate the natural curve of the cervical spine (lordosis). If your head rest positioned too high, it will rest against your occiput (which is the point of most curvature of your skull) and push your head ahead. This is a problem for short drivers and can cause neck pain and I would suggest add a seat cushion or something to raise your height a bit (keep the headrest in lowermost position) so the head rest sits in the ideal position.
It's extremely valuable to have a viewpoint from a doctor!
Based on some images of the crash test dummys, it does not seem that the bulging part of the head restraint is supposed to go into the curve of the neck. Here's one:

Name:  crash test dummy.png
Views: 118
Size:  312.2 KB

Also, as you rightly pointed out, such a setup is going to be a source of pain for short people. Unfortunately the polo does not provide as much space for me to put a large enough cushion for my passengers.
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Old 16th May 2020, 18:33   #21
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Default Re: Whiplash protection vs Chronic neck pain

Very interesting. That was my assumption and understanding but the picture you have posted seems clearly opposite to what I was saying. I also re read your post and I see that the issue is more for passengers. That is a real problem. Most drivers don't /shouldn't rest their head back but the passengers are under no such obligation/need.

I have never faced this issue in any car I have been and I guess as you said it must be an adjustment thing. I have had a Vento and have driven the Polo for quite a while as well as the i20 elite including for a 6 hour trip.

I get the problem and closest I have felt is in some airplane seats which have been very uncomfortable. Not sure what the solution is, but definitely reversing the headrest is a bad idea. I think your back rest idea doesn't seem so weird after all!

Last edited by Eddy : 16th May 2020 at 19:00. Reason: typos + spacing
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Old 18th May 2020, 14:08   #22
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Default Re: Whiplash protection vs Chronic neck pain

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Originally Posted by Amsdoc;
Also the bulging portion of the head rest is supposed to be in the region of the curve of the neck and not against the back of the head.
Well let me explain why not.
Inertia = inherent property of mass which tends to keep in it state of rest or motion till force acts on it.

Higher the mass = more intertia.

In case of a vehicle accident (crashing head-on) the person is moving forward at some speed, and it will continue to unless a force acts on it. In case we are not wearing seatbelt, intertia (or body's mass) will cause us to keep moving forward at same speed until we crash into the dashboard and wind shield and perhaps even fly out.

The same situation, but in reverse, happens when someone rear-ends into our vehicle. Our body is at rest and tries to remain so, however the seat moves forward because of the impact from the vehicle at rear. The good this is that since the backrest is in constant contact with the back and cushioned - this force is effectively and gradually transmitted all over our back and sets it in forward motion (along with the seat/backrest).

However, the head has a mass of its own and will continue to remain at rest, unless there is a cushioned head rest for it which transmits the force gently in order to keep the head together with the body.

If the center of mass of your head is positioned above the headrest, it will impart a torque on the neck, pulling the head out of the vertebral column in a rear impact.

Ideally we would want a similar padding for the neck, however the mass of neck bones is so low that they do not have enough inertia to pull themselves out.
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Old 18th May 2020, 15:31   #23
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Default Re: Whiplash protection vs Chronic neck pain

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If the center of mass of your head is positioned above the headrest, it will impart a torque on the neck, pulling the head out of the vertebral column in a rear impact.
Agree with you. For some reason my entire post above did not get published. I had said that there are various types of headrests. I didn't mean that your head should be above the head rest, that would put a hyperextension at the neck which is exactly what the head rest is trying to avoid. I meant the head rests that have a bulge in the lower portion but still continue above the bulge(quite a few cars have headrests like that). In those if you position them too high there will be neck pain as they will push your head in front.The ones shown in the above post you cant do that. Or the really straight ones like in the Jazz.
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