The Spine: Stronger Than We Think!

Main Points

1. The body is strong and resilient.
2. There is potential to improve.
3. Fear of movement and the impression that the body is weak is associated with persistent / chronic pain.
4. Abnormalities found on X-rays, MRIs, and CT scans may or may not be associated with pain.
5. There isn’t a “best” way to improve, we must create our own journey.

Estimated time to read: 15 min (2500 words)

We all know that there many examples of animals demonstrating tremendous ability to tolerate stress, tension, and load on their bodies. For example, it was documented in the early 1900’s that a type of shrew was able to withstand 1000 times it weight. Pretty cool isn’t it!! Another example of awesomeness was published in 2013 by researchers who found that the neck of Allegheny mound ants can withstand 5000 times its weight! Pretty impressive, right?

ant with stick

But what about humans? Aren’t we specimens that demonstrate spectacular strength and power as well? I truly think so!

In the 1960’s Alf Nachemson (1931 – 2006), one of the greatest spine surgeons and researchers of all time, was one of the first to publish data on the strength of the human spine by showing how much load is produced in various positions on the third lumbar (L3) disc. Here is a popular diagram from his study that pretty much all orthopedic surgeons and physical therapists have seen:

nachemson-graph-with-l3-spibna-lload.png

Pressure at the L3 disc increased to 150kg. (330 lbs.) when bending forward and to nearly 225 kg. (496 lbs.) when bending forward while holding a 44 lbs. weight. This shows how adaptable and strong our spine is, right? Isn’t that awesome too? Well, this study was interpreted quite differently and freaked out many who read this article. It put fear into the minds of health care providers to avoid positions that increased pressure, which in turn put fear into the general population to this date.

In 2007, the prestigious Spine Journal published an article in honor of Alf Nachemson after he passed away to show how his research impacted the medical field. The article included a Q&A about his work. He stated that this study was misinterpreted and had this to say:

“Yes. It was been widely misunderstood. And I probably misunderstood it myself for a while. This experiment has been misinterpreted as evidence that the disc is a significant pain generator and that increasing the biomechanical load leads to greater pain. But this study merely showed how the lumbar spine responds to normal physiologic loading in various positions of the body. It does not give any indication as to where the pain actually comes from.”

Well what do you know! OUR SPINE IS AWESOME!

Another study published data on the forces on the spine with various activities of five individuals and found the data below. As a reference: 1000N = 224.8 pounds and WP1 to 5 are the five participants in the study.

spinal-loads-5-peeps.png

Well, look that that! Washing the face can place close to 220 lbs. of force on the spine! For most people, it probably doesn’t feel like that much weight because the human spine can tolerate quite a bit of stress and it is amazing! There are muscles, bone, tendons, ligaments, and surrounding fascia that supports the body and provides the ability and potential to withstand significant loads.

This doesn’t mean that we can go crazy! Exercise and activity should be graded and progressed in a way to allow the body to adapt to become stronger. We must put the work in and it doesn’t happen overnight. Another point that I want to make is that disc issues do occur. The problem is that it is blamed as the cause of symptoms when it might not be involved at all. This will be discussed later.

If the spine is not as weak as was once thought, where does the concept of core/spine stability exercises fit in?

Well, much like Alf Nachemson’s work was misinterpreted. So was the work of Paul Hodges, the “father” of core / spine stabilization. He was one of the first to publish data on the transverse abdominis stating that the activation of this abdominal muscle can be delayed in people who experience low back pain.

A common misinterpretation was to teach everyone with complaints of low back pain to tighten their abdominals in various ways especially when lifting or carrying anything. Many people experience decreased pain, which is a good thing. But, what most do not realize is that pain often leads to excessive protective tension of the body. So, for some people, tightening abdominals with activity may promote even more tension within the spine which may increase stress and discomfort to a greater degree.

It is sort of like gripping a baseball bat or tennis racket too tightly while hitting a ball. It just does not work as well and is not as comfortable as using a relaxed grip. But if the grip is too relaxed, you will see a flying baseball bat. It turns out that problems may be associated (it is not a simple cause and effect) with too much or too little activity of the spine. Sometimes we do not know, so we cannot assume anything for our patients.

What this means is that the reason why people improve by tightening the abdominals may not be a strength issue. Some will say that pain is caused by improper motor control involving the nervous system or that “muscles are turned off”. I usually avoid this language because no one really knows for sure and the exercises given are often very similar. (This will also be explained in a bit)

In 2013 Paul Hodges wrote a commentary in the British Journal of Sports Medicine and stated the following:

“We do not know why motor control (core strengthening) interventions are effective. We don’t know that the effect is explained by increased stability of the spine due to activation of transversus abdominis and other deep muscles”

He then goes on to state this about core exercises:

“There are many candidate mechanisms and we need to keep an open mind to make sure that we do not miss the wood for the trees. While we have investigated the potential role of optimization of control of the spine by changing the activation of the system of trunk muscles, including transversus abdominis, the truth is likely to be more complex.”

What this means is that pain is complicated, and it is rarely due to just one thing that acts as the primary cause. So, if a core stabilization exercise helps to decrease pain, keep doing it! If it doesn’t help, let’s look at other factors.

We often blame structures like muscles, joints, ligaments, discs, and fascia when it comes to pain. But, we must look beyond structure and biomechanics. We must also understand the nervous system and how it works together with the rest of the body. Research on strengthening and flexibility have shown that changes within the nervous system plays a vital role with improvement. The same thing occurs with pain, the nervous system plays a very important role.

For example, the misinterpretation of Alf Nachemson’s and Paul Hodges’ research led to increased fear with spinal movement. It turns out that there is a link of fear of movement and persistent pain! (Remember that there is an association, not necessary a cause and effect). You can read more about it here and here. So, for some who experienced increased pain with exercise may have been taught to become more fearful of movement which may also increase excessive protective mechanisms including increased tension and something called sensitivity of the nervous system which is associated with persistent pain. (I will go over this in a bit as well.)

Other things that are linked with persistent pain is the feeling that something is worse than what it really is and that we are unable to do anything about it. In scientific terms, it is called catastrophization and decreased self-efficacy.

So here I am here to say that the is spine is strong and that there is potential to improve!

If it feels like the spine is weak, there is potential to make it stronger!

If you have been told to fear certain movements, there is potential to improve! Just don’t go crazy!

If you have been told your pain is due to osteoarthritis or a disc issue, there is potential to improve!

The list goes on and on!

hamster lifting

Wait a second… what about osteoarthritis, stenosis, disc bulges, meniscal tears and stuff like that? Is there anything that can be done about it except for surgery?

Well, guess what? The American College of Physicians made a statement in 2011:

“Diagnostic imaging abnormalities (such as osteoarthritis, stenosis and disc bulges) are extremely common, especially in older adults, but are poorly correlated with symptoms

This is difficult to believe because most of us do not know this. Alf Nachemson also made this same statement in the interview that I mentioned earlier, so this is old news! Osteoarthritis, stenosis, and disc bulges by itself do not necessarily cause pain! Read here for more detail. (it does need some updating) I listed a ton of research articles that make these statements. This is another example that shows that pain is not a simple topic and there is so much that we all do not know or understand. Myself included.

Disc issues can be related to pain that requires surgery or a rotator cuff tear can be unsuccessful with non-surgical treatment requiring repair, but what if surgery can be prevented? As a physical therapist, that is what I am about.

There are studies that show that people can do well without surgery for many issues including meniscal tears, rotator cuff tears, and disc herniations because the human body is adaptable and has the potential to heal. This includes disc bulges! Many patients have improved when they thought surgery was the only option.

It turns out that diagnostic imaging is important when there are red flags / signs of potentially serious issues such as loss of bowel and bladder control, history of cancer, sudden change or loss of balance, sudden weakness, the legs suddenly giving out, and unrelenting pain. If there are no red flags, guess what? Findings on MRI’s, x-rays and CT scans may be coincidental! It doesn’t mean we should ignore tests. It means that sometimes, we have no idea and it is important to understand that it may or may not be a huge factor for patients.

Other countries have medical associations that have similar guidelines as the American College of Physicians. The Royal Australian and New Zealand College of Radiologists and The National Institute for Health and Care Excellence in the United Kingdom are a couple of examples.

It is important to understand that our body changes with age. This includes our skin, hair, vision, and joints. Which may or may not be associated with pain.

This means that there is another reason give the body a chance to improve!

We must realize that our bodies are amazing and designed to tolerate significant loads! This type of positive frame of mind has been shown to lead to better outcomes. For those with significant osteoarthritis, we should think that motion is lotion for our joints. Movement is how nutrients are pushed into cartilage and bones.

Don’t forget, we must progress in a graded and appropriate manner based upon individual ability. There are many ways to do this and studies show that there isn’t a specific way that works the best. So, moving the body (it can be yoga, Pilates, walking, going to the gym, or doing the chicken dance) in ways that do not feel threatening to the mind and body may be a great way to start. This can help to decrease sensitivity of the nervous system. It also helps to do something enjoyable which increases the likelihood of continuing exercises for the long run.

What if simple movements are painful?Let’s discuss pain sensitivity

First, we must understand that pain is normal. It is vital for survival to help react to dangerous or potentially harmful situations. Pain becomes a problem when it is persistent and continues after the body has healed and one reason that pain persists is related to changes with sensitivity of the nervous system.

An injured site naturally becomes sensitive to protect the area as it recovers. Lightly touching a bruise is great example: It can be quite painful if you lightly touch a bruised area, but we know that light touch is obviously not going to cause more damage. It is just painful and as the body heals, the sensitivity diminishes.

Unfortunately, sensitivity of the nervous system can continue after the injured site heals. This is important to understand because nerve sensitivity is associated with osteoarthritis. In laboratory animals, changes in barometric pressure which often indicates a change in weather patterns can increase nerve sensitivity. So maybe it isn’t the arthritis, but the change in sensitivity that is the main reason why we tend to experience increased pain as the weather changes. If osteoarthritis is the sole culprit, then the level of pain should be constant depending on the level of arthritis. But that just doesn’t happen.

With physical therapy, I have had many patients tell me that they no longer experience pain or that the achiness they experience is less during rainy weather!

Keep in mind that it can take time for the nervous system to become overly protective, fearful, sensitive, and develop the feeling that we cannot do anything to improve. Many may be in states of over protection for years. That means we must give our bodies time for the nervous system to change and adapt in a more positive way. Learning and understanding pain (such as reading this article) can change how we look at ourselves, which can help decrease sensitivity of the nervous system.

There is also a book about the sensitive nervous system on Amazon.com written by David Butler, one of the top pain researchers out there.

sensitive nervous system book

There is no doubt that pain is a complicated issue that has many contributing factors that will be discussed in future posts. What has been clear is that movement exercises are very important to help improve ability and decrease pain.

Pain Sensitivity Part 2:

A second component to pain sensitivity is that our society is not active. Our bodies are not used to lifting heavy things. So, when we do things such as beginning an exercise program or doing something the body is not accustomed to doing such as going out to help a friend move furniture, our spine and nervous system may be easily irritated. This can increase protective mechanisms that may trigger a painful response. A gradual increase in activity is one way to minimize or prevent the body from triggering excessive protective mechanisms.

Just remember that there is no best way to improve.

If you ask around, people will tell you what worked or didn’t work for them, but you must find your own journey toward improved ability. There are specific exercises that are better for certain activities or sports. But there isn’t a best exercise when it comes to deceasing pain. There is your way and you must find out what it is. So, it may be best to start off with something that is enjoyable. As you feel better, increase weights, distance, and intensity in ways that your body feels comfortable with.

Please keep in mind that understanding that our spine is generally strong is just one component to improvement, but it is a huge one!

Further Reading:

Featured Image: By Cobragym1 – Own work, CC BY-SA 3.0,https://commons.wikimedia.org/w/index.php?curid=31572768

Cool Animals:

Castro C, Blaine L, & Castro C. The exoskeletal structure and tensile loading behavior of an ant neck joint. Journal of Biomechanics. 47 (2); 2014: 497-504.

Stanley WT, Robbins LW, Malekani JM, et al. A new hero emerges: another exceptional mammalian spine and its potential adaptive significance. Biology Letters. 2013;9(5):20130486. doi:10.1098/rsbl.2013.0486.

Artwork:

https://pixabay.com/en/photos/?q=notepad&hp=&image_type=all&order=popular&cat=&min_width=&min_height=

Alf Nachemson:

Danielsson A, Brisby H, Hansson T, Holm S, Holm AK, et al. Alf Nachemson, MD, PhD (1931–2006). Spine: January 15th, 2007 – Volume 32 – Issue 2 – p 149-150

Nachemson A. The load on lumbar disks in different positions of the body. Clin Orthop Relat Res. 1966;45:107.

Loads on the Spine:

Rohlmann A, Pohl D, Bender A, et al. Activities of Everyday Life with High Spinal Loads. Hug F, ed. PLoS ONE. 2014;9(5):e98510. doi:10.1371/journal.pone.0098510.

Rydevik B, Hansson T, Szpalski M, Aebi M, Gunzburg R. Alf Nachemson, MD, PhD, 1931–2006: an exceptional pioneer in spine care. European Spine Journal. 2007;16(3):303-305. doi:10.1007/s00586-007-0330-1.

Paul Hodges:

Hodges P. Transversus abdominis: a different view of the elephant. Br J Sports Med. 2008 Dec;42(12):941-4. doi: 10.1136/bjsm.2008.051037.

Fear Avoidance:

Pincus, T., Vogel, S., Burton, A. K., Santos, R. and Field, A. P. (2006), Fear avoidance and prognosis in back pain: A systematic review and synthesis of current evidence. Arthritis & Rheumatism, 54: 3999–4010. doi:10.1002/art.22273

Wertli, Maria M. et al. Fear-avoidance beliefs—a moderator of treatment efficacy in patients with low back pain: a systematic review. The Spine Journal , Volume 14 , Issue 11 , 2658 – 2678

Wertli, Maria M. et al. The role of fear avoidance beliefs as a prognostic factor for outcome in patients with nonspecific low back pain: a systematic review. The Spine Journal , Volume 14 , Issue 5 , 816 – 836.e4

Pain Catastrophization:

Leung L. Pain catastrophizing: an updated review. Indian J Psychol Med. 2012 Jul;34(3):204-17. doi: 10.4103/0253-7176.106012. PubMed PMID: 23441031; PubMed Central PMCID: PMC3573569. Free full text

Quartana PJ, Campbell CM, Edwards RR. Pain catastrophizing: a critical review. Expert Rev Neurother. 2009 May;9(5):745-58. doi: 10.1586/ern.09.34. Review. PubMed PMID: 19402782; PubMed Central PMCID: PMC2696024. Free full text