The majority of episodes of acute lower back pain are caused by a muscular strain (such as from lifting a heavy object, a sudden movement or a fall). Even though this doesn’t sound like a serious injury, the low back pain can be very severe and last for several hours, several days or even a couple of weeks or months.
When the muscles in the back are strained or torn, the area around the muscles can become inflamed. With inflammation the muscles in the back can spasm and cause both severe lower back pain and difficulty moving.
Healing from acute low back pain
Fortunately, muscle strains usually heal with time (a couple of days or weeks) because muscles in the low back have a good blood supply to bring the necessary nutrients and proteins for healing to take place.
However, an episode of low back pain that lasts for more than one - two weeks can lead to muscle weakness (since using the muscles hurts, the tendency is to avoid using them). This process leads to disuse atrophy (muscle wasting), and subsequent weakening, which in turn causes more low back pain because the muscles are less able to help hold up the spine. This also causes mechanical joint dysfunctions in the spine that can be corrected with chiropractic care.
Exercise helps prevent acute low back pain
As a general rule, people who are active and well-conditioned are much less likely to suffer from low back pain due to muscle strain, as regular exercise stretches the muscles so they are less likely to strain, tear or spasm.
There are three types of muscles that support the spine:
- Extensors (back muscles and gluteal muscles)
- Flexors (abdominal muscles and iliopsoas muscles)
- Obliques or Rotators (side muscles)
While some of these muscles are used in everyday life, most do not get adequate exercise from daily activities and tend to weaken with age unless they are specifically exercised. A complete exercise program for the low back should consist of a combination of stretching, strengthening, and aerobic conditioning.
Common conditions that cause lower back pain
For patients with low back pain that lasts longer than two weeks to three months, or with predominantly leg pain, a more specific and definable problem is often the source of pain. Several types of low back and leg pain tend to be more common in either younger or older adults.
Common types of low back pain for young adults (< 60 years old)
- Leg pain and possible numbness
Pain that radiates through the buttocks, as well as pain and possibly numbness that radiates down to the foot, is frequently caused by a disc herniation in the lumbar (lower) spine. This type of pain is usually worse after a long period of standing or sitting.
See also Lumbar disc herniation
- Mechanical low back pain
Low back pain in young adults that is caused by movement (such as bending forward, running) is commonly caused by a syndrome called degenerative disc disease. This condition can result from a twisting injury that weakens the disc. The low back pain symptoms of degenerative disc disease can become chronic and may tend to fluctuate and at times become significantly worse.
See also Degenerative disc disease
- Low back pain (and possibly leg pain) that worsens when standing or walking
Sometimes a vertebral body in the low back slips forward, causing stress on the disc, which in turn may cause low back pain and may sometimes cause leg pain. These painful symptoms are sometimes caused by a stress fracture that occurs at a young age.
See also spondylolisthesis
Common types of low back pain for older adults (>60 years old)
- Low back pain that is worse in the morning and in the evening, and stiffness
Low back pain that is most pronounced first thing in the morning and later in the day is often caused by facet joint osteoarthritis (degenerative arthritis), a condition that involves breakdown of the cartilage between the facet joints in the back. The pain and stiffness is a result of the lack of cartilage between the joints.
See also Facet joint osteoarthritis
- Pain down the legs when walking and standing upright
Leg pain that occurs when walking, and increases with more walking, can be caused by conditions such as lumbar spinal stenosis or degenerative spondylolisthesis. Both conditions place pressure on the nerves at the point where they exit the spine. Standing upright, such as in normal walking, increases pressure on the nerve and results in leg pain.
See also Lumbar spinal stenosis and Spondylolisthesis