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NL Leg length difference?
One of the most well-known examples is a "leg length" difference. We hear incredibly often that a previous therapist indicated that the complaints were at the low back come from a difference in leg length. When we start looking critically at perceiving leg-length difference in practice, there are many snags in this.
Changes in attitude is often something a therapist or practitioner has taught themselves. Compare it to this example when you are looking for a red car you start seeing them more often too! In this we cannot blame them either because you are looking for something to treat. But in most cases, a leg length difference is not easily noticeable or less than 1 cm. And when your leg length difference is less than 1 cm, it is probably irrelevant to developing symptoms.
(Maybe it's also just really hard to do?) A study was published in 2016 where two experienced chiropractors were unable to get agreement on a group of people they had to assess for leg length difference. Comparison of Supine and Prone Methods of Leg Length Inequality Assessment
And not only does the previous study show that pointing to a leg-length difference as THE reason for your low back pain is very slippery ice. As early as 1984, a study appeared in the Lancet which clearly indicates that a leg length difference has little or no impact on developing low back pain. Does unequal leg length cause back pain? A case-control study
Extremes are often very interesting and often tell us a lot. An example is people who have undergone leg amputation. When we look at this group of people, we see that the leg length difference factor does not affect whether or not they have low back pain. By this I mean that people with a leg length difference do not have more or less back pain than the group without a leg length difference.
Interesting? Read more here. Low-back pain in transfemoral amputees: is there a correlation with static or dynamic leg-length discrepancy?
Do you want to know when a leg length difference could potentially affect your low back? Then read here further on another page. (blog leg length).
Pelvic misalignment
Another well-known example is the crookedness of your pelvis. Of course, this goes nicely together with a leg length difference because one may cause the other. I don't mean that a different position of your low back nor is your pelvis made up. But the influence it has on the onset of low back pain often is. It often boils down to this: a tilt or twisting of your pelvis is often imperceptible. The idea that a slight variation in position is the cause of your symptoms is very unlikely. Our low back is simply not that vulnerable.
Another example is a back that is too hollow. As with our pelvis, there is an awful lot of variation in the hollowness of our lower back between people. We simply don't know how much hollowing is bad. When is it too much? When we start looking at the evidence again, we often see that there is none!
Lumbar lordosis: study of patients with and without low back pain
The biomechanics of the lumbosacral region in acute and chronic low back pain patients
Relationship between mechanical factors and incidence of low back pain
So you have to ask yourself whether treating, or wanting to change, an overly hollow back is really that helpful? People who are so panicky about an overly hollow back are often also the people who say that long sitting or office work is so bad for your back. While this is just the opposite of these attitude?? Do you still get it?
A small kernel of truth
As humans, we walk on two legs. This is probably why there is quite a lot of pressure and strain on our low back. If we compare this with people who often sit in a deep squat position (the hollow back now becomes convex), as people often do in Asia, we do see that in this group the spine is less subject to wear. Even in animals that walk and move on four legs, we see wear in the areas of the spine where the curvature is sharpest. But even if it were the case that in the western world we would see more wear and tear develop because of the way we sit and move, this does not mean that we also experience more pain in the low back. The degree of wear and tear is not a measure of the degree of pain experienced.
This brings onto us the other often stated cause for your back pain. Wear and tear! A great example of this is the twin spine study:
Twins from the United States, Canada and Finland were followed over an entire period of time. This study looked at various factors that could potentially play a role in the development of osteoarthritis symptoms, or wear and tear. This study specifically deals with osteoarthritis located in the spine. The study concluded that wear and tear in the spine is largely hereditary. This hereditary factor weighs many times more heavily than, for example, a heavy profession or a sport where one can expect where the spine is subjected to a lot of stress. Now you're probably thinking; great then! But what also turns out is that more physical activity and muscle mass actually have a beneficial effect on not developing more osteoarthritis in the spine. In twins of which one smokes and the other does not, we do see more of osteoarthritis.
The belief that our spine is a fragile block box that needs to be straightened or just gets crooked has often led people to have less confidence in their own bodies. They are genuinely convinced that something is wrong while in 99% of all cases we speak of a normal anatomical variation. The danger is that people risk becoming their "diagnosis". What you can do about your symptoms, though, we will discuss in our next blog!
