Low Back Pain
One of the most common issues I see new patients for is low back pain. In fact, the World Health Organization estimates the lifetime prevalence of low back pain to be 60-70% in industrialized countries! The most common time for people to experience low back pain is between ages 35-55, but really, it can strike at any time. If any of you reading this have experienced an episode of low back pain, you know that it can feel really horrible and greatly limit your activity.
There are five major bones in the low back called vertebrae. We number them from the top to the bottom, so L1 stands for lumbar vertebrae 1, and it is the top vertebrae closest to your ribs. The bottom one is L5, short for lumbar vertebrae 5, and it is located just above your sacrum, which is the bony part of your pelvis that you can feel if you put your hands right at your buttocks. In between the vertebrae are intervertebral discs, which act as cushions between the bones. Each disc is named for the level above it and the level below. So, if you hear someone talking about an L4/5 disc, that means the disc is the one in between L4 and L5. The facet joints are tiny joints that occur at contact points between the vertebrae, and there is a pair of them at each spinal level.
At each level of the spine, there are a pair of nerves that come out of holes in the bones called foramina. If the nerve gets compressed at any point along its path, this can cause symptoms of pain, weakness and numbness. Overlying these deeper structures are many different muscles that you can easily feel if you touch your back with your hand, just below your skin.
The most common causes of back pain that I see are lumbar sprain/strain, facet arthropathy, spinal stenosis and lumbar radiculopathy. The sacroiliac joint, which is lower down towards your buttocks, can also be a source of what people perceive as low back pain, but I’m going to cover that separately in a different post.
A lumbar sprain/strain usually comes on quickly. It is caused by a spasm or overuse of the muscles in the low back. The pain is often diffuse, meaning it covers a large part of the back, and often the back is sensitive when touched. The pain does not typically go down the legs.
Facet arthropathy occurs when, as people age, arthritis develops in the tiny joints between the vertebrae. The onset of pain is usually more gradual and can be localized to one side or both. It is often associated with stiffness in the morning or after sitting for a long period of time. Like a sprain, the pain does not typically go down the legs, but it can be felt in the upper part of the buttocks.
Spinal stenosis occurs when changes, typically relating to aging, cause a narrowing in the canal which surrounds the spinal cord and nerves. The pain is normally in the low back and goes down one or both legs, especially when patients are walking. Sometimes patients describe this pain as a “heaviness”. Sitting down or bending over usually produces a dramatic improvement in the symptoms.
Lumbar radiculopathy, often called sciatica, can have a fast onset or can be gradual. Many patients feel pain in the low back and shooting down one leg. The pain can be associated with numbness, tingling and weakness. The pain is caused by compression of one of the spinal nerves, often by a disc, but sometimes by arthritis in the bones of the back.
There are many other rarer types of low back pain that I think about when I am evaluating a patient’s back pain. Many of the questions that I ask during the initial interview help to rule in or out all of these types of disorders, and the examination helps to confirm my suspicions. Sometimes, I will decide after the interview and examination that imaging is needed to make the diagnosis. Usually these imaging tests are either X-rays, or an MRI.
Once a diagnosis is made, then I work with the patient to develop a tailored treatment plan. Normally this will involve some combination of medications, other modalities like physical therapy, and injections. I’ll go into detail about these different types of treatments in other posts, but for now, just know that there are a LOT of different options to get things under control.
I hope that helped to explain low back pain! Remember, the best way to get a diagnosis specific to you is to see a pain management physician in person.