More talk about air- vests

[RAyers]

[QUOTE=Winding Down;7072764]
and it is inflated prior to the bone fragments forming, right?..[/QUOTE]

Not necessarily. I can see the mechanics of restricting hyperflexion without dissipation of the forces resulting in burst fractures rather than plough or other, less significant, spine fractures. In this case the fractures occur after vest inflation. There is a play here between rigidity of the spinal column during impact versus dissipation of the impact forces along the muscles and tendons. If given a choice, I’d rather risk hyperflexion fracture versus burst fracture.

[eqsiu]

@Winding Down;7072764

and it is inflated prior to the bone fragments forming, right?

But think of the case where the horse falls and you’re never far enough away from it to engage the inflation mechanism. Horse breaks your bones, gets up, THEN the air vest inflates. Highly unlikely even when only considering that a fall is certain, but still a big enough risk that I will not spend money on an air vest until I see enough reproducible studies showing that an air vest + vest is significantly safer than a vest alone.

[wildlifer]

[QUOTE=deltawave;7072616]
No, I’m not worried about being uncomfortable. I’m worried about bone fragments being driven into my spinal cord by the force of the thing inflating inward. [/QUOTE]

LOL, thank you, my dear delta!! I am now daydreaming about internal decaptitation.

It doesn’t really matter whether it inflates “in” or “out” – there will be (a) pressure on your spine and (b) it will deflate and all the bits and pieces will move. Eeeee, spinal cords freak me out; having had a needle in mine, NO TOUCHY!

[Countrywood]

It makes zero sense to me how an outward inflating vest could "drive " bone fragments into soft tissue. The air in the vest would cushion the fall, making if far less likely for bones to fragment in the first place.

Even with an inward inflating vest, I doubt it could happen. Surely they at least tested for that, people are not idiots and nobody would be buying a vest that fractured bones when it inflated.

[Countrywood]

Lack of knowledge about basic anatomy? Some of the conclusions here make no sense at all. But I am no expert, but an airbag causing bone fragments seems impossible.

[RAyers]

Did you know you can decapitate yourself and NEVER come into contact with anything? Yes, you can fracture the spine even with airbags. It is seen quite often in automobile accidents.

It is the COMBINATION of inflation and impact that can cause the stated issues. And no, no manufacturer had to test any of that as there is no standard requirement, as I stated previously.

[eqsiu]

[QUOTE=Countrywood;7072872]
It makes zero sense to me how an outward inflating vest could "drive " bone fragments into soft tissue. The air in the vest would cushion the fall, making if far less likely for bones to fragment in the first place.

Even with an inward inflating vest, I doubt it could happen. Surely they at least tested for that, people are not idiots and nobody would be buying a vest that fractured bones when it inflated.[/QUOTE]

Have you read the few testing studies provided? No. As far as the manufacturers have reported, that has not been tested. They have tested impact force dissipation only. And in very specific circumstances. I could not find any studies testing the effects of the vests themselves on the human body.

[eqsiu]

[QUOTE=RAyers;7072895]
Did you know you can decapitate yourself and NEVER come into contact with anything? [/QUOTE]

Off topic, but this is why people should leave their babies rear-facing as long as they can. I get tired of hearing “I want to be able to SEE them in the rear view mirror.” Anyway, as an example of that, the weight of a baby’s head moving forward is enough to sever that baby’s spine.

[Snugglerug]

I’m sure there are situations when wearing an airvest could cause injury rather than protect from it. Just like there are freak situations where a seat belt might trap you in a burning or submerged car. But in [I]most[I] cases seatbelts protect, so we play the odds. Better some bruising from the seatbelt than being ejected from the car. So are airvests likely to protect from injury in most cases? In the cases where they may cause injury, how rare and how severe? These are the questions I would love to see answered, but unfortunately it’s tough to recreate all possible scenarios.

Thinking back, there’s always been much initial resistance to safety gear that we now all consider required. Continuing with the seat belt example–remember when they started making it the law to wear them? People went nuts–I’ll get trapped in a burning/submerged car–it will break my ribs–I can’t breathe with that thing on–it wrinkles my clothes. But now I can’t remember the last time I was in a car without one on.

Same thing with riding helmets. If I hit wrong it will break my neck–I lose peripheral vision so I can’t see a problem coming–it’s too hot/heavy/ugly–it gives me headaches. But now most riders wear them. In our collective minds, the good has outweighed the bad, and the products themselves have improved.

Of course, there are examples of safety products that did cause problems too–like the first generation of car airbags.

Will be interesting to see where we are with air vests in 5 years.

[Winding_Down]

^^^ yes…

It is all one’s own estimation of the relationship between the probability of safety versus the probability of harm.

My estimation, based on every sort of data available, is that the Prob of S is larger than the Prob of H.

I also remember the seat belt revolt and I also remember a researcher at VA Tech with whom I worked who received funding from the auto industry trying to show that seat belts were dangerous… Ahhh… the world of objective academic research, :lol:

[eqsiu]

[QUOTE=Snugglerug;7072914]

Will be interesting to see where we are with air vests in 5 years.[/QUOTE]

Hopefully armed with more detailed safety data.

[RAyers]

[QUOTE=eqsiu;7072907]
Off topic, but this is why people should leave their babies rear-facing as long as they can. I get tired of hearing “I want to be able to SEE them in the rear view mirror.” Anyway, as an example of that, the weight of a baby’s head moving forward is enough to sever that baby’s spine.[/QUOTE]

Works for adults too. One of the big take aways in the spine core for residents here is:

“MAKE SURE THE HEAD IS ATTACHED. IF IT IS NOT, DO NOT PASS GO. GO TO SURGERY.”

[Janet]

[QUOTE=Countrywood;7072874]
Lack of knowledge about basic anatomy? Some of the conclusions here make no sense at all. But I am no expert, but an airbag causing bone fragments seems impossible.[/QUOTE]

Given RAyers and Deltawave’s “day jobs”, their knowledge of both “basic” and “advanced” anatomy is well above most of ours.

They ARE experts in that field.

[Jealoushe]

[QUOTE=Janet;7073001]
Given RAyers and Deltawave’s “day jobs”, their knowledge of both “basic” and “advanced” anatomy is well above most of ours.

They ARE experts in that field.[/QUOTE]

yes, exactly. I’d take their word for it.

[eqsiu]

[QUOTE=RAyers;7072949]
Works for adults too. One of the big take aways in the spine core for residents here is:

“MAKE SURE THE HEAD IS ATTACHED. IF IT IS NOT, DO NOT PASS GO. GO TO SURGERY.”[/QUOTE]

The disadvantages of having a nice sensory ball atop our necks.

[deltawave]

I don’t know, it makes quite a lot of sense to me, and I got “Honors” in anatomy. :lol:

The concern is not that the vest might CAUSE fragments. The concern (on my part, among others) is that the high-energy inflation could cause bone fragments to MOVE. Maybe inflating “in” or inflating “out” is immaterial (Do we know this for certain? I didn’t think so) but if I’ve got a bone fragment 3 mm from my spinal cord because I had a rotational fall I don’t want a big air-filled bag exploding anywhere near my neck as my horse gets to its feet, thanks all the same.

This is not my only concern with them, but it’s one of them. I am perfectly happy to buy and wear one when the evidence is sufficient to convince ME that there is more benefit than risk. Thus far, they have not made the cut. Personal risk assessment.

[Snugglerug]

[QUOTE=deltawave;7073088]
I don’t know, it makes quite a lot of sense to me, and I got “Honors” in anatomy. :lol:

The concern is not that the vest might CAUSE fragments. The concern (on my part, among others) is that the high-energy inflation could cause bone fragments to MOVE. Maybe inflating “in” or inflating “out” is immaterial (Do we know this for certain? I didn’t think so) but if I’ve got a bone fragment 3 mm from my spinal cord because I had a rotational fall I don’t want a big air-filled bag exploding anywhere near my neck as my horse gets to its feet, thanks all the same.

This is not my only concern with them, but it’s one of them. I am perfectly happy to buy and wear one when the evidence is sufficient to convince ME that there is more benefit than risk. Thus far, they have not made the cut. Personal risk assessment.[/QUOTE]

Deltawave, I don’t know anything more than the average lay person about anatomy, and since I started this thread to learn, maybe you can help make this more clear for me. Here’s my question: in the average fall, the order of “go” should be 1. Separate from horse. 2. Airvest Deploys. 3. Rider hits ground/jump/whatever. So in that case, the airbag would deploy prior to any injury, so there wouldn’t be any bone fragments to drive into the spine. Can you explain the scenario you’re thinking of where that could happen? Are you thinking of a malfunction of the airbag where it deploys too late–after you’ve hit the ground? A rotational fall where you don’t become separated from your horse until after you hit the ground?

I’m trying to find out how likely the scenario is to apply to me. Malfunction could happen to anyone. Do we know if there have been any cases of an airvest deploying too late? Rotational falls could too–but I’m doing BN on a horse who has gone training, (and has stepped down to teach me, not due to any physical issues) so I think I’m more at risk of just a stupid fall caused by me than a rotational fall. Sure, it could happen, but again, looking at the odds for my particular situation.

To be clear, I don’t expect an airvest, a helmet, or a body protector to save my life in a worst-case scenario. But I do hope that that they can be the difference between an injury that lays me up for a while or causes me ongoing problems, and one that I walk away from.

[Aaspen]

I can tell you a quick bad case scenario. It happened to me, and while this was before airvests were invented, nothing would have helped (except a more average fall from a horse). Riding horse at walk, horse rears, horse flips over with rider still attached to horse, horse lands on rider resulting in open book pelvic fracture. Horse gets up, rider then becomes detached from horse. Airvest would then inflate possibly making fracture worse. (Not that it could have gotten much worse than that). Anyway, this happened to me (like I said, it was before airvests, so I added that possibly scenario to illustrate the potential). I do wear an airvest everytime I ride because I feel as though statistically speaking, the chance of that occurring again is slim. I equate it to the person who brought up seatbelts. Yes, there are a few scenarios where not having a seatbelt on could save your life, but on average, wearing a seatbelt will be a good thing. ( let me add I also had L1, L5, S 1-3, and and an acetabular fracture. )

[deltawave]

Yes, a rotational fall where the vest deploys after horse and rider land would be one scenario.

This is not the only reason I have not bought one, but it is one of my main questions as to their safety above and beyond what a normal vest provides. Since it is “active” as opposed to “passive” (like a helmet or regular vest) there is more to think about in terms of the dynamics of injury. Reed can do a much better job than I can in sorting out the forces on the spine that cause the various injuries with other types of inflatable vests. But I am not convinced that they actually make the spine, in particular, safer in ANY way and in fact they may increase the risk of some types of spinal injury via changing the dissipation of forces. Again, I hope Reed can clarify because if I got Honors in Anatomy, I also barely scraped by with B’s in Physics.

I care about my spine more than just about anything besides my brain. I want to see some REAL evidence that these gadgets don’t make the risk of spinal injury higher.

[RAyers]

[QUOTE=Snugglerug;7073180]
Do we know if there have been any cases of an airvest deploying too late?[/QUOTE]

Yes, and also when they don’t deploy at all (e.g. the rider forgets to replace the cartridge, the bayonet does not puncture the cartridge, the cartridge is installed incorrectly, the lanyard breaks, the lanyard fails to activate the bayonet…). All are examples of cases where the vest failed to deploy.

And here is another piece of wisdom I hear in the spine group: “The spine is the brain. You don’t mess with the brain, you don’t mess with the spine.”