With 80 to 90% of people in the U.S. experiencing low back pain at some point in their lives, it seems as if this particular ailment is inevitable. Although your great grandmother Matilda might have passed down a genetic tendency for some types of low back pain, there are other risk factors for low back pain that can be avoided or minimized entirely.
First, though, the bad news.
Researchers at King’s College London have identified a gene that is linked to lumbar disc degeneration (LDD), one of the most common forms of low back pain, affecting over a third of women between the ages of 30 and 50. Researchers analyzed MRI scans of 4,600 people whose genes had been mapped. They found that the presence of degenerated discs was strongly tied to a variant of PARK2, speculating that this gene may be “switched off” in people with lumbar degenerative disc disorder.
If this genetic link makes degenerating discs seem inevitable, the good news is that researchers were unable to identify exactly why this gene was switched off, postulating that perhaps environmental factors had a role. Why, exactly, is this good news? Because this potential environmental link means that in many cases, low back pain is within our control.
By assessing our personal risk factors and making changes, we can help to prevent or minimize low back pain in our lives. At the 2015 annual meeting of the American Academy of Orthopaedic Surgeons (AAOS), researchers presented several major risk factors for low back pain, some of which may be surprising.
A review of electronic medical records from 13 health care systems that included over 26 million people across the U.S. found the following risks factors strongly increased the possibility of a patient experiencing back pain.
People who smoke tend to be less active, and less activity means stiffer joints and more potential for back pain. Seventeen percent of patients with low back pain also reported nicotine dependence. There is also a neurological link between addiction and chronic low back pain.
Almost 15% of patients reporting alcohol abuse or dependence experience lower back pain. Researchers did not indicate why this is, but there is other research that shows bones are unable to absorb calcium when excessive alcohol is consumed, a factor that can lead to fractures and pain. Heavy drinkers also tend to lead a more sedentary lifestyle.
Mood disorders and chronic pain have long been closely tied, and the study above found that just over 19% of people diagnosed with depressive disorders suffered from low back pain, twice the level found in a person without depressive disorders.
This risk factor is not surprising. Obesity is strongly tied to a host of physical ailments, and low back pain is no exception. Nearly 17% of people in the review had a body mass index (BMI) of 30 or higher, indicating obesity.
The above risk factors for low back pain are known as “modifiable” risk factors because patients are able to modify or change their behavior to create a drop in their risk. Quitting smoking and increasing physical activity to strengthen back and core muscles may be just the thing needed to decrease all but occasional episodes of back pain.
For some people, though, the problem may be mechanical. Empa, in collaboration with researchers at Balgrist University Hospital and University of Pittsburgh, is trying discover just how the way in which we use our backs impacts the wear-and-tear aspect of low back pain. Researchers created a computer model that could accurately identify the type of joints in a spinal column as well as how different types of movement impacted them over time. They found that incorrect movement increased chances of injury to the spinal column, and that injury then increased impacts on neighboring discs. Like a row of dominos, the effects of the injury spread along the spine, forecasting pain that is widespread and debilitating. This grim picture is lightened by the promise of utilizing the same technology to more accurately pinpoint areas of injury and increase success rates of back surgeries.
Humans evolved fairly quickly to walk on two legs, and their musculoskeletal system may not have been able to keep up. New research from BioMed suggests that the shape of our vertebrae may be the reason why humans experience more back pain and issues than non-human primates. Between 20 and 78% of people experiencing back pain are suffering from intervertebral disc herniation, a condition where the jelly-like substance that cushions each vertebrae bulges and does not provide adequate cushioned support. When this substance protrudes vertically down, the result is a bulge of cartilage called Schmorl’s nodes.
In an attempt to explain why humans experience more back pain than the primates that they are so closely related to, researchers looked at the vertebrae of 141 humans, 56 chimpanzees (a species that walks on its knuckles), and 27 orangutans (a primate that climbs using all four feet as hands). Over a third of the human vertebrae (54) showed Schmorl’s nodes and showed more similarities with the knuckle-walking chimpanzee vertebrae than the healthy vertebrae showed with either non-human primate. This finding indicates that the form of locomotion and our rapid evolution towards bipedal movement may play a significant role in our human tendency towards back pain.
The causes of back pain can range from the genetic to the evolutionary, with human habit and attitudes in between. The best way to address these causes is to eliminate the risk factors that we can while continuing to work towards more effective treatments for the ones we cannot.
What risk factors can you change for a healthier back?
Image by Kevin Borland via Flickr