Backpacks

              As August continues to march along we are entering the season of “back to school.”  With many of our patient’s being students or parents, it is time to examine how school can impact the health of our spines.  Recently, we have been getting a lot of questions from the people of San Angelo on the healthiest ways to wear a backpack.   As chiropractors, we aim to be spinal health experts, so today we are going to dive into the proper ways to wear a backpack in order to keep your spine healthy.

Proper way to wear:

              When doing the research for the blog post, it was pretty surprising how limited the proper position of backpacks have been studied.  I think of wearing a backpack as a staple of going to school, so I just assumed that this had been well researched. Wearing a backpack was even a habit that I maintained well into adulthood between graduate level school, and general ease of carrying things.  So knowing how to properly wear a backpack seems like valuable knowledge.

              During my investigation of backpack positioning, I found that researchers divided backpack positions into three categories.  Low, where the backpack straps are loose and the bottom of the bag sits below the waist and gluteal muscles. Middle, where the backpack rests from the middle of the back to the level of the waist. High, where the backpack sits significantly above the waist, closer to the shoulders. 

The problem with the low position is that the weight of the contents of the backpack are applying an excessive force low in the back.  This causes a backwards pelvic tilt, and applies unnecessary pressure on the joints of the lumbar spine.  Wearing a backpack in this position can be a significant contributing factor for a lower cross postural change, leading to tight hip flexors, lower back, and hamstrings.  Wearing a backpack too low is a fairly well known mistake, so what some students have done is overcorrect into the high position.  When the backpack sits too high on a student’s back, it causes too much weight to be carried in the shoulder and neck muscles.  Compensating for this, causes an upper cross postural change and can lead to neck dysfunction, shoulder pain, and even numbness and tingling in the hands.  As with many areas of life, there needs to be a healthy balance, but this will look different for every student as we come in all shapes and sizes. Aiming for a healthy middle position relieves the shoulders and neck from carrying the weight, while also not forcing the pelvis to excessively tilt backwards. Have students wear the backpack with the bottom of the bag right at the level of the waist or gluteal muscles. Finally, it is important to listen to your body, if your shoulders and neck are feeling sore lower the backpack height, or if the lower back and hamstrings are feeling tight, make sure to raise it up.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5862447/

Weight:

              While backpack positioning is the thing that I get asked the most about for students, a factor that is even more important is the weight of its contents.  Let’s think for a second about what the backpack is doing.  It is resting on top of our shoulders, and compressing our spine, in order to carry things and keep our arms free.  It’s a pretty amazing invention for convenience sake, but if abused can have consequences for our bodies. 

              When a backpack is too heavy there are multiple areas that can be repetitively hurt in our body.  The first is where the straps rest on our shoulders.  This is actually a very sensitive region anatomically, because the nerves that control our arms exit out of our spine at our neck.  These nerves then travel under our first rib and into our arms.  So think about a heavy backpack weighing down on top of our ribcage and collarbone, it is constricting the area and forcing the muscles at the base of the neck to work harder.  If too much weight is added it can apply excessive pressure on these nerves that travel to our arms, leading to pain or in extreme cases numbness and tingling in the hands.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6267109/

              Another region that is at risk with excessively heavy backpacks is the lower back.  In between each of the bones of our spine is a structure called an intervertebral disc.  Squishy and gelatinous in nature, the disc serves us as a mobile, shock absorbing structure.  When excessive weight is added to the spine the discs are compressed.  This weight accumulates in the lumbar spine, where a large amount of intervertebral disc injuries occur.  Unfortunately, disc injuries are something that plague younger people more frequently because of how the discs change as we age. And this is more prevalent than you might think.  Studies have shown that for students aged 12-18, carrying heavy backpacks is not only strongly associated with back pain, but it is also an independent risk factor for poorer general health.

https://pubmed.ncbi.nlm.nih.gov/12942009/

So what is too heavy?  It seems that lately texbooks are getting larger (and more expensive), as well as students needing more and more supplies.  Obviously, a 6 year old off to their first day of first grade will need to have a lighter backpack than your high school student, but beyond that all of our bodies come in different shapes and sizes.  A good rule of thumb, research supports, that limiting the contents of your backpack to no more than 10% of your body weight is best for spinal health.  Beyond this point postural changes and discomfort indexes start rising rapidly. Studies have also demonstrated that the vast majority of students at all levels are exceeding this limit.

https://pubmed.ncbi.nlm.nih.gov/32310211/

So as we power through August and get our students back to school, remember that how you wear your backpack, and how heavy it is are very important for our health.  Remember to keep that backpack in the middle of the back, and not to let it get too heavy.  If improving your posture, or just generally bettering your health interests you we would love to talk more in depth about your particular health goals.  Please always feel free to contact us at Concho Valley Chiropractic.