Evidence-based justification for extended rear-facing
Updated January 2022
It’s all the rage among parents nowadays: extended rear-facing. If you’re turning your child to face forward before they’ve reached the limits of their carseat, then you’re old-schooling it and increasing your child’s risk of injury in a crash. Many pediatricians still hold onto the now ancient recommendation of turning kids forward-facing at age 1 and 20 lbs., even though their own professional organization, the American Academy of Pediatrics, hasn’t recommended that since before 2002. You were probably in grade school then.
Why is it so critical for kids to stay rear-facing?
When you use the carseat right, it protects them and you from potentially being forever changed if you get into a crash.
Simple Physics Lesson
A carseat will always move toward the point of impact (Newton’s 1st Law). In a frontal collision—at 53.5%, statistically the most common type of severe/fatal crash—the entire back of a rear-facing carseat will protect the head, neck, and spine of a child as it rotates down toward the front of the vehicle. Even in a side impact, which is a more serious type of crash due to its proximity to passengers, there is usually an element of frontal movement, such as a vehicle moving forward through an intersection, as it’s hit from the side. So a rear-facing carseat will rotate down and forward, then toward the side where the impact occurs.
Click each graphic to see the motion:
Compare this to a forward-facing child in a harnessed carseat. In a frontal crash, the carseat still rotates down and forward toward the front of the vehicle, and the child will be flung forward into the harness and forward of the carseat shell. In a side impact, again the carseat rotates down and forward toward the front of the vehicle; the child comes forward into the harness and out of the carseat shell and there is rotation toward the vehicle door where the impact occurs. Because the harness is holding only the shoulders and hips, the head, arms, and legs are flung violently forward. If the harness is loose, which is one of the most common mistakes a caregiver makes, there’s a high likelihood of the child hitting the vehicle seat in front or the side pillar.
Anatomy 101
The folklore is that a child’s neck muscles aren’t developed enough to keep a baby’s neck safe in a car crash, which is why they have to face the rear of the vehicle. I suppose that’s true in a way: it does take babies time to develop their musculature so they can hold their heads up to keep their airways open. But the muscles don’t protect the fragile spinal cord, which is the bundle of nerve fibers that forms the central nervous system and is connected to the brainstem. No amount of baby push-ups will strengthen your child’s muscles to the point of protecting his spinal cord.
The bones of the spinal column are what actually protect the spinal cord and in infants and young children; they aren’t completely fused together for years. One of the most important cervical bones, the Atlas (C1), is what attaches the head to the spinal column. Drawings show where it ossifies, or fuses, at varying times: the anterior arch fuses around age 7, while the posterior neural arches fuse around age 3. Before it fuses, the Atlas and Axis (C2), the 2nd vertebra that the Atlas nestles into, are made of bone and cartilage, which is very pliable. These two vertebrae are held in place by ligaments, which are very elastic (lax) to allow the child to grow.
Studies of infant cadavers have shown that vertebral columns can stretch up to 2” but that the spinal cord is damaged after only ¼”. Given that a baby’s head accounts for ¼ of its total body size versus 1/7 an adult’s size, plus the immaturity of its vertebrae and laxity of the ligaments holding those vertebrae together, rear-facing seems the obvious choice.
The child’s large head shifts the fulcrum of movement—where the head swings forward—higher, elongating the spinal column and potentially causing catastrophic damage to the spinal cord. Before age 8, this fulcrum is in the upper cervical spine, at C2-C3. After age 8, the fulcrum shifts down to C5-C6, where it stays into adulthood. When you hear the term “internal decapitation,” it encompasses this movement of the upper cervical spine since the head swinging forward must happen in order for the ligaments to stretch and pull the head from the Atlas.
Another devastating injury that doesn’t show up on x-ray is called Spinal Cord Injury without Radiographic Abnormality (SCIWORA). This is when the spinal cord stretches because of the elasticity of the ligaments and cartilage in the spinal column. An x-ray will show normal bone alignment and no fractures, but the spinal cord may be irreversibly damaged. Remember that this bundle of fibers can only stretch up to ¼” before having catastrophic damage.
The evidence is clear. Rear-facing carseats protect the most fragile part of a developing child’s body: the head and spinal column. The 2018 American Academy of Pediatrics Policy Statement recommends rear-facing to the weight or height limits of the child’s carseat and instructs their pediatricians to counsel parents about rear-facing at each health visit. The National Highway Traffic Safety Administration (NHTSA) recommends rear-facing as long as possible.
Favorite Links
The American Academy of Pediatrics (AAP) has recommended since 2002 that after age 1 and 20 lbs., children should ride in a rear-facing convertible seat until reaching the weight limit of that carseat. They amended that policy in August 2018 to recommend rear-facing to the weight or height limits of the carseat.
Note how the legs fly away from the back of the vehicle seat during the rear-facing test on the left. In the forward-facing seat, the properly secured dummy bends nearly in half during the crash test. Photo courtesy Kathy Weber, ret., UMTRI, and SafetyBeltSafe USA.
2018 AAP Policy Statement on Child Passenger Safety, includes table summary of best practice recommendations and algorithm chart
2018 AAP Guidelines: rear-facing as long as possible, up to the limits of the car safety seat; includes virtually all children under 2 years of age and most children up to age 4
2018 AAP Technical Report: summary of evidence supporting best practice recommendations
The above video is a simulation comparing properly restrained 18 mo old models rear-facing to forward-facing in a 35 mph crash from the Children’s Hospital of Philadelphia Center for Research and Prevention (CIRP)
SafetyBeltSafe USA’s opinion on how long children should ride rear-facing. (How Long Should Children Ride Facing the Back of the Car?)
After reviewing studies from the U.S. and Sweden, a study published in the highly regarded British Medical Journal advises keeping children rear-facing until age 4. (www.bmj.com/cgi/content/full/338/jun11_2/b1994?view=long&pmid=19520728)
Leg injuries account for 28% of significant injuries faced by forward-facing children in crashes (Jermakian, J.S., et al. “Lower Extremity Injuries in Children Seated in Forward Facing Child Restraint Systems.” Traffic Injury Prevention 8 (2007): 171-179.)
This analysis shows how leg injuries are common among forward-facing children (Bennett, T.D., et al. “Crash Analysis of Lower Extremity Injuries in Children Restrained in Forward-facing Car Seats During Front and Rear Impacts.” Journal of TRAUMA® Injury, Infection, and Critical Care 2006;61:592-597
A tightly installed rear-facing carseat allows the vehicle and carseat to absorb crash forces and increases “ride down,” the amount of time it takes a body to come to a stop in a crash. The longer the ride down time, the less chance of injury. (http://www.car-safety.org/rearface.html)
Since there is almost always an element of forward motion in a side impact—such as when a vehicle is going straight through an intersection when it is struck on the side by a red-light runner—a rear-facing seat does a better job of keeping a child’s head contained within the safety of the seat. (http://carseatsite.com/whyrearfacing)
Evenflo is now requiring that children be age 2 before forward-facing in their convertible and combination carseats.
Approximately 75% of kids in Sweden rear-face until at least age 4. From 1999-2006, only 4 rear-facing children under age 4 were killed in crashes and their deaths were due to circumstances unrelated to the direction the carseat was facing (fire, drowning, excessive intrusion). During that same timeframe, 6 kids under age 4 facing forward in booster seats were killed; 3 of these crashes were potentially survivable crashes had the children been in rear-facing carseats. (http://www.bmj.com/cgi/content/full/338/jun11_2/b1994)
Anecdotal evidence suggests that infants around ages 10 mos.-18 mos. enter a fussy stage that makes it difficult to put them into any carseat, rear- or forward-facing. Many parents prematurely switch the rear-facing carseat forward-facing thinking that the child is objecting to riding rear-facing, when the child is objecting to being restrained at all. Visit the Car Seat Safety forums at www.car-seat.org and you’ll hear from other experienced parents regarding this phase.
The above video shows how the dummy stays contained in the seat during a rear-facing crash test. The tape on the dummy’s head is for measurement and doesn’t affect its head during the test.
This video is the companion video to the one above and shows a side view of the crash test. Note how little the head moves.
The above video shows a properly installed forward-facing seat. Note the seat belt stretch and how far forward the dummy bends.
The above video from Norway shows the differences between rear- and forward-facing carseats in an animated crash.
The above video from the Buckle Up With Brutus at The Ohio State University demonstrates the difference between rear-facing and forward-facing in crash tests.
If you need more convincing, take it from Dr. Marilyn Bull, a noted pediatrician from one of the country’s best pediatric hospitals, Riley Children’s Hospital in Indiana. This video was produced for, and used in, the current Child Passenger Safety Technician course.
Vehicle crashes are the number 1 killer of children. Protect your children to the best of your ability. Follow best practice.
To the person who commented on how it’s absurd to use a booster for an 8 yr old I would like to tell you that my 10 yr old son has been in a booster seat since he outgrew his carseat. He is in a backless booster right now but a booster none the less. He is 51 inches tall and 56 lbs and does NOT fit correctly in the seat without the booster.
http://www.carseat.org has a simple 5 step test to check to see if your child still needs a booster. It is not necessarily about height, weight or age it is how they FIT sitting in the car/truck. Seatbelts were designed to fit an average size man not a child!!!
My son has never been teased by anyone and he doesn’t argue with me much about it because he knows he will not win. I do not bend with safety issues. Just as I would not let him play with a gun or smoke a cigarette I will not let him become a moving projectile in the car. He can argue with me all he wants as long as he is alive and here to argue with me.
Oh and my son is not in a bubble or deprived of anything. He does karate, snowboarding, baseball, swimming, he has a bike, a scooter, etc. He has always been given every opportunity to do whatever he wants. My only rule is he must have safety in mind so he wears his helmet and any other safety equipment as needed.
I’d be interested in seeing video on a crash test done with a forward facing seat that had the latch system installed as well as the top tether that ties the top of the child’s car seat down. Do you guys know of one of those that we can see?
To whomever commented that their 4 year old was squished, please do some research on the avilable carseats!
My daughter was 11lbs, 4ozs at birth and is consistently in the 90th percentile for height and weight. But I know there are carseats available that will safely and comfortably take her into the toddler years rearfacing.
For those who have tall and skinny kids, the Radian XTSL is a great choice. It will take your chil rearfacing to 45lbs and forward facing HARNESSED to 65lbs.
My super tall 5 year old sister is rearfacing in a True Fit right now. They can easily put their legs over the side or fold them indian style. You don’t even need to teach them this; little kids know how to do these things easily.
I’d rather have my child fold her legs indian style than deal with a snapped spine. It really does boggle my mind that debate even exists in this topic.
thanks for putting this together in one post – I’ve added it to my car seat bookmarks!
Looking, I’m not going to rebut your arguments because the links I’ve given in the blog post do that quite adequately. I would like to say that I do agree that all drivers should drive defensively and properly, they should signal with every lane change and turn, and they should make use of every available safety device available to them. However, I can drive as defensively as I can, but it’s the drunk/impaired/texting/cellphonetalking driver who isn’t that’s going to crash into me. I can’t stop at every green light before proceeding through the intersection just to make sure it’s safe. I can’t drive defensively when the guy behind me has an attitude and wants to drive me off the road. I prepare for those situations by making sure my kids have the safest equipment available to them and that I’m wearing my safety equipment. I hope you are too.
Kristy, I assure you that in a crash test, all seat belts are locked per legal requirements. If you look at the seat belt path itself, the red piece is a belt lockoff which locks the seat belt. So while the shoulder belt looks as though it isn’t locked, the lap portion is. There is always considerable belt stretch in crash situations on both the seat belt and the harness, which is why both must be snug.
That video of the front facing crash test was absurd. The seatbelt was clearly not locked as intended. My kids are too old for this to apply to them, so other than pointing out that seatbelts in modern cars have locking mechanisms so you can lock the seatbelt in place, I will stay out of this. 🙂
Is it overkill to get your kid a flu shot for your toddler? To have them wear a life preserver? To keep poisons, matches and weapons out of reach? Of course not, despite the fact that some parents may feel these things are overkill. As Heather indicated in her references, studies are showing that it is not overkill to keep a child rear facing to at least 2 years old and preferably beyond. Motor vehicle crashes claim more lives of children than any other cause, and extended rear-facing is proving to be one method to reduce these numbers.
Having a child in a carseat is hardly like putting them in a “bubble”. What freedoms are they losing, exactly? The freedom to escape a seat belt more easily and roam about unsafely in the car?
Children’s attitudes toward being in a child seat are another issue. In cases of behavior, each child is indeed unique. For example, for those who cry because of leg room, those same reclining seat backs that can help accomodate a front facing seat also give a little more leg room for rear-facing.
while I’m all for safety, I don’t feel having a child crammed up in a rear facing seat all that safe. Also, children are all unique. Different sizes, heights, weights and won’t fit into this mold. For example, when my oldest was four he no longer fit his booster seat. He was just too long, and the older booster seats had bars that went across the legs, and his poor legs would be squished to the point he’d complain of pain. My youngest is heavy enough and old enough for front facing. She also has proven her dislike for the rear facing by lifting her head up and smashing herself back into the seat when we are in the car and moving. She moves the whole seat. I also do not agree with leaving a child in a booster seat until they are 8yrs old. I might as well stick my kid in a bubble. Oh and that whole seat not reclining if it’s front facing is outdated. More vehicles have back seats that are already reclined, or it’s possible to recline them so that a front facing seat can sit properly in the vehicle. I think people need to practice using car seats properly, but also learn how to be defensive drivers and drive properly themselves. That in itself will keep one safer. As for keeping rear facing. There is safe and there is overkill.
Thanks, this is great. I’ve already passed this on to mom and MIL.
Thanks for all your hard work, Heather, this is a really great resource!
Thanks Heather! This is great! I already posted it to my FB!!
Heather, thanks for compiling this great easy-to-link-to list of information! I’m definitely bookmarking it.
Wow! Thanks so much for putting all these resources together. Definitely will hang on to this page.
Thanks for clarifying, Kecia. I wouldn’t have used the photo if I thought the harness was incorrect. It’s actually acting like a Britax harness: they are a bit looser over the belly while staying snug on the shoulders. His hips are also shifted over to his left, which accounts for the slack. I bet when he woke up, the slack in that strap disappeared because he was no longer limp.
LOL! C’mon people – do you REALLY think we would post a picture with blatent misuse? His harness is/was properly adjusted. Since it’s my kid (albeit 4 years ago)and I took the picture – I can guarantee that it was fine. It’s just the way he’s slumping to one side while sleeping that is causing that effect. Plus, you can see it’s adjusted properly since it’s straight and snug on one side. The MA harness isn’t one continuous strap like a Scenera so it’s not possible for one side to be looser than the other (unless something is wrong). Now obviously the picture wasn’t staged which is why is doesn’t look perfect but it does a nice job illustrating that toddlers are much more comfortable in the RF position (especially when sleeping) due to the recline angle and their ability to prop their feet up.
Awesome! Bookmarking!
Great blog but the loose harness in the pic with the rear facing blue Marathon is driving me nuts!
Bravo! This is an excellent compilation to refer parents and caregivers to for rear facing advocacy, thanks!
It’s great to have all of these resources in one place–this will be where I send parents wanting more information on extended RF from now on! You ROCK 😉
Great blog!! Thank you. I’m bookmarking this.
Wow, what a great article to point people to! Thanks for putting this all together.
Thank you so much for putting this together. Now I have a link to send parents who think I’m crazy for erf. My almost 3yr old loves it!