The new study, Cervical Spine Motion during Extrication, makes an interesting contribution to the research, uses intriguing methods, and is very relevant to EMS.
It is usual practice for EMS to go through great efforts to maintain cervical spine immobilization after an MVC. The patient will often have both a cervical collar and a "short board," or KED, applied. The EMS crew will then go through elaborate efforts to move the patient onto a long board right from the car seat, avoiding any active participation by the patient.
|The somewhat messy reality|
This is a lot of effort, but the hope is that, by avoiding motion of the cervical spine, there will be no further, or "secondary," trauma to the spine. The actual risk of secondary injury is controversial, but immobilization is the current usual practice.
Well, a natural question to ask is: Does it work? Do these multiple devices and great physical efforts avoid motion of the cervical spine?
Well, this question has been approached in a number of ways in the past, but Missouri researchers took a new approach. They used a simulated extrication scenario, and tracked motion of the cervical spine using video motion capture, the technique used to, among there things, render Tom Hanks into a cartoon character.
|Looks kind of creepy to me, but Hanks can get away with anything.|
For the simulated extrication scenarion, they used a mock-up of a Corolla that had been in a bad head-on MVC. They recreated the postions of all the posts with PVC, replaced the surfaces with chicken wire, and replaced the seatback with Plexiglass. This way, they could record the extrication from all angles.
The participants were all paramedics with more than 5 years of experience - some of them also played the victim, along with some non-EMS people.
The victims exited the vehicle in 4 different ways:
- They were instructed to get out on their own, and walk over to the backboard and lie down.
- They first had a cervical collar placed, but still had to get out on their own.
- Collar was placed, and then the EMTs proceeded to maneuver the patient onto the board while "holding c-spine," instructing the victim to not offer assistance.
- A collar was placed, as well as a KED, before being moved onto the board.
So how much neck motion did they see? A lot!
Looking at the graphs, you can see how much motion, in each plane, they observed with each extrication method.
Now here's the weird thing: method #2 (c-collar and "get out on your own") showed significantly less cervical motion than both methods #1 and #4!
For example, take a look at "Graph C" from just above:
The results are seemingly paradoxical, but it squares with some of my experience. Placing the KED and moving the patient to the backboard always seemed to go smoothly if the patient was slender, short, and driving a large car.
Smaller car, bigger person - it doesn't go so smoothly...
|E.g. Try putting a KED on Klump.|
For example, in the last year, Xenia FD in Ohio, as well as New Haven, CT, have started using method #2 for certain lower-risk trauma. A number of other agencies are said to be following suit.
And although it's not a prehospital policy, Bridgeport Hospital is now encouraging nurses and EMTs to remove backboards as soon as patients arrive in the ED - no doctor involved! This shift in practice was prompted both by the risk to patients that backboards pose, and the scant evidence that supports their use once the patient has arrived at the hospital.
|And you get your board back right away!|
This study suggests that those policies may not be as risky as previously imagined, and may, in fact, be more conservative than the "usual practice!"
The Bottom Line
This study adds to the growing body of research that suggest that our approach to spinal care may be quite different in the near future!
(In the meantime, of course, please stick to your local protocols and guidelines.)