Lower back pain (LBP) is the most common reason for missed work days by North American adults. Also commonly referred to as low back pain, it is one of the most common injuries most of us tend to experience at some point in our lives.
The lower back is the region that sits below your rib cage. It is also called the lumbar region. This part of your back plays a critical role in everyday activities such as walking, twisting, turning or even just standing up. It also supports your head, spinal column and upper body and provides a conduit for the spinal column nerves carrying sensations between your lower body and your brain.
To perform these tasks, the lower back contains a complex and tightly interlinked network of muscles, nerves, bones and other tissues. It is the complexity of this network that makes the lower back so susceptible to injury and the resulting pain.
The complexity of the network can also sometimes make it difficult to detect the exact source of lower back pain and its cause.
According to Arthritis & Rheumatism magazine, between 9% and 12% of adults are suffering from LBP at any point in time. Approximately 25% of adults report experiencing it over any one month period. Worldwide, about 40% of adults report experiencing this pain at some point in their lives. This figure is generally believed to be higher in wealthy countries (possibly due to their older populations).
In most cases, the onset of lower back pain is between the ages of 20 and 40 and it tends to affect men and women equally. The highest prevalence of this condition is observed between the ages of 40 and 80. This means that lower back pain is expected to have a greater impact on society overall as the population ages.
The Nature & Variability Of Lower Back Pain
Because LBP is not a specific injury or disease, it can arise from any of a wide variety of underlying problems. In fact, as we shall see below, it sometimes arises without any specific causes that doctors can identify.
For the same reason, the symptoms of low back pain can vary widely from one individual to another. The longevity, severity and even the location of the pain can be very different depending on the underlying cause. In addition, the accompanying symptoms (other than the pain) can be very different.
Although LBP is a widespread problem, the good news is that it tends in many cases to be a short term problem that can be eliminated with simple home based treatments. Sometimes, a brief bed rest or change in patterns of activity can be all that we need to make it go away in a short period.
However, it is important to be aware that, in some cases, the underlying causes can represent very serious (and even life threatening) problems. Consequently, it is important to seek medical attention as soon as it becomes clear that the causes of LBP may be more than just transitory
In what follows below, we shall consider the various possible underlying causes of low back pain. The nature of the pain and how it varies depending on the underlying cause will also be discussed. We will then consider the various home based, non traditional and surgical treatment options for each type of LBP.
Causes & Symptoms Of Lower Back Pain
The main possible causes of LBP include the following:
Strains & Sprains
Back sprains & strains contribute to a large proportion of LBP cases. Heavy lifting, for example, can easily cause the muscles and ligaments in the back to become overstretched or even torn. When this happens, the symptoms are likely to include pain and stiffness in the lower back area. In some cases, you may also experience muscle spasms from this type of injury.
Back pain due to this cause is normally referred to by doctors as “mechanical” pain.It is also likely to be acute low back pain that lasts less for a relatively short period if treated properly. With adequate rest, physical therapy and other home based treatments, LBP from a sprain or strain can go away in as little as 6 weeks in many cases.
One way to avoid this type of back injury and the associated LBP is to lift with proper technique, i.e. by bending your legs rather than your back. This technique will transfer much of the pressure of lifting from your back to your stronger quadricep and hamstring muscles. The result will be less risk of a back sprain or strain injury.
Poor posture is another widespread cause of lower back pain. Many of us, particularly when sitting for long periods, tend to allow our shoulders to hunch forward instead of keeping them straight. Some individuals also do this while standing or walking.
This sub optimal posture eliminates the natural curvature of the lumbar region. In addition, it results in too much of the weight of our upper bodies being borne by the lumbar spine. Over time, this can result in a sore and painful lower back.
To treat this type of lower back pain, we can wear an upper back or posture brace that gently reminds us to keep the shoulders straight. Doing this will restore the natural curvature (lordosis) of the lower back and reduce the pressure on it from the upper body.
Lumbar supports can also help to maintain proper lordosis when we are forced to sit for extended periods (such as during a long car or plane trip).
Spinal discs are rubbery pads that sit between the vertebrae of your back and are held in place by the ligaments and muscles surrounding the spine. The discs serve to keep the vertebrae separated so that they do not rub together, which would be very painful.
The spinal discs can sometimes suffer an injury in which the inner material of the disc starts to swell and push through its outer casing (membrane). As a result, the nerve roots exiting from the spinal cord can be compressed. The result can be extreme pain, sometimes accompanied by muscle spasms. Furthermore, the pain from the trapped nerve can sometimes migrate away from the lower back and enter an arm or leg.
The lower back pain from this type of injury is likely to be more long term than that from a back sprain or strain. In addition, it is unlikely that home based self care will yield any benefits other than pain relief.
Sciatica is a special case of the herniated disc problem mentioned above. In this case, the herniated disc presses on the sciatic nerve that connects the spine to the legs. As a result, your lower back pain radiates down to your legs and feet. The pain is of a “burning” nature and can also sometimes feel like “pins and needles”.
The LBP caused by herniated discs tends to be classifiable as a chronic low back pain, as it is longer term in nature than the pain from a strain or sprain.
This is a result of the narrowing of the spinal column that compresses the spinal cord and nerves travelling through the column. It is another form of chronic LBP.
Stenosis can itself be a result of damage to the spinal discs. If they degenerate over time, the spinal column can narrow in such a way as to compress the spinal column and nerves.
The LBP due to spinal stenosis is usually accompanied by numbness, cramping or weakness in the lower back or elsewhere.These symptoms tend to be more severe when you are walking or even standing.
Scoliosis is an abnormal curvature of the spine that is usually diagnosed during childhood. This curvature causes lower back pain and other problems similar to those we have described above in relation to poor posture.
This puts pressure on the soft tissues and vertebra of the lumbar region, leading to low back pain.
Some types of lower back pain are due to inflammatory conditions in the lower back such as rheumatoid arthritis or ankylosing spondylitis (a rare type of arthritis that tends to cause inflammation between the joints of the spine).
LBP With No Apparent Cause
In some cases, patients experience lower back pain with no cause that is apparent to their doctors. In these cases, the treatment options focus on pain relief without addressing any underlying causes.
Other Causes Of LBP
Other potential causes of lower back pain include:
Spondylosis, a degenerative disorder that over time causes loss of spinal structure and function;
Kidney or bladder problems such as kidney stones;
Tumours in the lower back
Diagnosing The Cause Of Your Lower Back Pain
To determine the cause of your LBP, your doctor may need to:
Review your medical history;
Conduct a physical examination to understand the nature of your pain (i.e. where it is, when it becomes more severe, does it restrict your movement, etc.);
Assess your reflexes and whether you can detect certain sensations (in order to understand whether the nerves to your lower body are affected by your lower back pain).
If your LBP continues after a couple of weeks of home based treatment and seems to be sub acute or chronic in nature, your doctor may decide to order additional tests:
Imaging tests such as an X ray, MRI or CT scan;
Bone density tests to see whether your LBP could be caused by a structural back problem such as inadequate bone strength;
Nerve conduction test to check the operation of the nerves serving your lower body.
If the initial part of your examination does not reveal anything that is chronic in nature (such as a herniated disc) your doctor may decide to try a period of self care at home:
Abstaining from strenuous physical activity;
Changing your activity pattern to avoid activities that aggravate your LBP. For example, if standing for prolonged periods exacerbates the pain, try to sit down every now and then.
Apply ice or a cold compress to your back for periods of 20-30 minutes every 2-3 hours to ease your lower back pain;
If your LBP is accompanied by stiffness in your lower back muscles, you can also try a heat compress to improve blood circulation. Alternatively an occasional warm bath or shower can provide similar benefits;
Taking over the counter pain relief medication for further pain relief.
If these treatments do not ease your lower back pain, there are some additional options that doctors can try:
Referral to a therapist who can design a physical therapy exercise program to loosen and strengthen your lower back muscles;
Prescribing Non Steroidal Anti Inflammatory Druds (NSAIDs) to ease both your pain and any inflammation that may be present;
Corticosteroid injections for stronger control of inflammation and to suppress the immune system. This may be an option to control an auto immune cause of your LBP such as rheumatoid arthritis.
Other non traditional approaches that you may wish to try at this point include:
Spinal manipulation by a chiropractor;
Surgical Treatment Of Your Lower Back Pain
If your LBP is severe and resistant to the treatments mentioned above, doctors may bring up the option of surgery. Although it is usually a last resort, surgery will usually be considered at an earlier stage if there is an indication of a serious or life threatening problem such as cancer.
The specific surgical procedure will depend on the underlying cause of your lower back pain. However, some of the key surgical options include:
Relieving pressure on the nerve root due to a herniated disc by performing a “discectomy”. The surgeon removes a bony part of the spinal canal to relieve the pressure;
Spinal fusion, in which the surgeon removes the discs between adjacent vertebrae and then fuses the vertebrae together. He or she does this using bone grafts or metal screws;
Spinal decompression, in which the surgeon removes a part of the spinal canal to make the canal broader. This helps to relieve pressure on the nerves travelling through the canal.