3 Leading Proximate Causes of Lower Back Pain and Sciatica-The 3 Most Common Diagnoses from MRIs
Lower back pain and sciatica together represent the #1 reason patients come to G3 for physical therapy. We are not unique in this regard, as some report that over 80% of Americans will suffer at least one episode of lower back pain or sciatica in their lifetime. The cost to the US economy is somewhere in the neighborhood of $100 billion dollars annually, with lost wages and the cost of medical care leading the way. And the problem is only increasing, with the incidence of lower back pain and sciatica nearly doubling over the past 15 years. Clearly, this is a problem of epic proportions, and one that shows no evidence of slowing down.
Another interesting statistic is that well over 50% of initial lower back pain or sciatica incidents resolve within 6 weeks, with people seeking various forms of treatment. On the surface, this is an encouraging statistic. But, diving a little deeper reveals a more disturbing trend – up to 80% of people whose initial lower back pain resolved relatively quickly, suffer a recurrence of lower back pain within two years. Even more disturbing – these recurrences are often worse than the original occurrence, meaning, lower back pain problems are often cumulative, with recurring problems presenting with more and more severe symptoms.
So, my point that lower back pain and sciatica are huge problems is inarguable. More importantly, what are the 3 leading proximate causes of lower back pain and sciatica? Before getting into this, I wanted to briefly discuss the concept of proximate cause vs. ultimate cause. Proximate cause can be defined as the event that immediately leads to a particular problem. So, in our context, the proximate cause of lower back pain and sciatica would be that cause that is directly responsible for the lower back or sciatica pain. Again, though, a deeper dive can often reveal that beyond proximate causes lie ultimate causes. Ultimate causes can be defined as those events or occurrences that are ultimately responsible for the problem. Indeed, in the case of lower back and sciatica pain, there are proximate causes and ultimate causes, and choosing which causes are treated, and how, will often determine the long-term success of a treatment strategy for lower back pain and sciatica.
So, without further ado, the 3 leading causes of lower back pain and sciatica are:
1) Herniated disc (aka: HNP)
2) Degenerative disc disease, spinal stenosis and arthritis, and
3) SI (Sacro-Iliac) joint dysfunction
Each of the three causes have some distinct properties, while some share some common characteristics.
- Herniated disc. This is typically a problem of the young, typically causing problems with people 35-40 years old and younger. First, a little anatomy of the spine. The spine is made up of segmented series of bone called vertebrae. The upper 7 vertebrae make up the cervical spine (aka “Neck”). The middle 12 vertebrae make up the thoracic spine. The bottom 5 vertebrae make up the lumbar spine (lower back). Below the lower back are several fused vertebral segments called the sacrum, the bottom of which is the tailbone. Separating each of these vertebral segments are discs. The discs provide cushioning between the vertebral segments and also provide space between segments: room so that nerves branching off the spinal cord (spinal nerve roots) can travel unimpeded. When we’re young and haven’t had the chance to beat up our bodies, our discs are like grapes – squishy discs that are full of water and pulp that act as great shock absorbers for the vertebral segments. Discs are great at absorbing compressive forces (from jumping, going down stairs, running) but not so great at absorbing shearing and rotational forces. Expose a disc to enough of these forces (twisting, flexing) and the “grape skin” will split, ultimately allowing the juice and pulp to squirt out, which, by itself, can cause quite a bit of pain. The real problem is when the “pulp and juice” squirt out and rest on a spinal nerve root. That can cause extreme nerve pain, often running down the leg (sciatica) and can be an excruciating problem. Patients that have lower back pain and sciatica caused by herniated discs usually have more pain with sitting or flexing, with the pain relieved by standing, lying on the stomach or bending backwards. The pain is often worse in the morning and gets better as the day progresses.
- Degenerative disc disease (DDD)/Spinal stenosis/Arthritis. This is typically a problem of people over 45 or so. As we age and beat up our spines, our discs go from resembling grapes to resembling raisins. As such, they flatten out, and the “juice or pulp” dries out. As a result, the discs are not as effective as shock absorbers, and they cause the vertebral segments to get closer to each other, often pinching (impinging) on the spinal nerve roots that exit the spine between the segments. People with lower back pain or sciatica caused by DDD/spinal stenosis/arthritis usually have more pain standing or walking, with the pain relieved by flexing, sitting, or lying down on their back with their feet up. Their pain is usually worse as the day progresses, and they can have major pain if they sleep on their stomachs. We’ve all seen extreme cases where an elderly man or woman is at the grocery store, bent over, leaning on their shopping cart as they walk around shopping.
- SI joint (SIJ) dysfunction. SI joint dysfunction is significantly less common than the previous two causes, but is still a significant cause of lower back or sciatic pain in women (particularly pre- and post-pregnancy) and anyone who has slipped and fallen on their backsides or tailbones. The SI joint is where the sacrum (bottom triangle of the spine) and the pelvis (ilium) join up. This is usually an extremely stable joint (there is a left and a right SI joint) that, for various reasons can become unstable and cause lower back pain, groin pain and sciatic pain. The reason it is more common in women has to do with hormones and pregnancy. When women are pregnant (and possibly menstruating), they release a hormone called relaxin. Relaxin helps prepare the pelvis to expand when a woman gives birth. By its nature, relaxing is designed to make the pelvis unstable, thus making the SI joint unstable. The SI joint can also become unstable when a person slips and falls on their backside or tailbone. Again, compared to the other main causes of lower back pain, SI joint dysfunction is less common, but it’s still a significant cause of lower back and sciatic pain.
So, now that you know the three leading causes of lower back pain and sciatica, what do you do with that information? The answer to that can be tricky. On the one hand, that information is valuable, in that it gives you a jumping-off place where you can start doing something about your pain. The underlying cause of lower back and sciatic pain can help direct you as to where to turn for relief. All of our doctors of Physical Therapy at G3 are lower back and sciatic pain specialists, and have all successfully treated hundreds of patients complaining of lower back or sciatic pain. If you want to make an appointment to see one of our back pain specialists, please call G3 at 760-205-1500 and make an appointment. If you have any questions or comments that I can help answer or clarify, please feel free to leave a comment below.
On the other hand, as helpful as knowing the proximate causes of your lower back or sciatic pain, the real gold is in knowing the root causes of your lower back or sciatic pain. To learn about the 3 leading root causes of lower back pain and sciatica, stay tuned for a subsequent blog where I take a deeper dive into this common and debilitating problem.
If you have been diagnosed with a herniated disc, degenerative disc disease, or sciatic joint dysfunction and want to learn more about non-surgical treatments, sign for our FREE workshop or call 760-205-1500 for an evaluation.
January 20: FREE Back Pain Workshop – Learn to manage lower back pain and sciatica without medication, injections or surgery. REGISTER HERE