Low back pain is one of the most frequent problems treated by doctors. Four out of five adults will experience significant low back pain sometime during their life. After the common cold, problems caused by the lower back are the most frequent cause of lost work-days in adults under the age of 45.
The lower or lumbar spine is a complex structure that connects your upper body (including your chest and arms) to your lower body (including your pelvis and legs). This important part of your spine provides you with both mobility and strength. The mobility allows movements such as turning, twisting or bending; and the strength allows you to stand, walk and lift. Proper functioning of your lower back is needed for almost all activities of daily living. Pain in the lower back can restrict your activity and reduce your work capacity and quality of enjoyment of everyday living.
HOW IS LOW BACK PAIN DIAGNOSED?
Most cases of low back pain are not serious and respond to simple treatments. Your doctor can accurately diagnose and effectively treat most types of low back pain in the office. You will be asked about the nature of your symptoms and whether you sustained an injury. You also will have an examination of your spine and legs. For many episodes of low back pain no expensive tests are needed for initial assessment and treatment.
If your pain is severe and not responding to treatment or if you have significant leg pain, some imaging tests may be required. Plain X-rays will show arthritis and bone diseases, but will not show soft tissues such as the lumbar disks or nerves. For conditions or injuries that involve these soft tissues, CT scan (computerized tomography) or MRI (magnetic resonance imaging) may be needed. Occasionally, a bone scan will be needed to assess bone activity and electrical tests, EMG (electromyography) may be needed to determine if the spine condition has caused nerve or muscle damage.
WHAT ARE THE COMMON CAUSES?
Low back pain can be caused by a number of factors from injuries to the effects of aging.
Low Back Sprain and Strain - The muscles of the low back provide power and strength for activities such as standing, walking and lifting. A strain of the muscle can occur when the muscle is poorly conditioned or overworked. The ligaments of the low back act to interconnect the five vertebral bones and provide support or stability for the low back. A sprain of the low back can occur when a sudden, forceful movement injures a ligament which has become stiff or weak through poor conditioning or overuse.
These injuries, or sprain and strain, are the most common causes of low back pain. Frequently, a combination of other factors may increase the likelihood of injury or disease:
- poor conditioning
- improper use
The natural effects of normal aging on the body, in general, and low back, in particular, are osteoporosis or decreased amount of bone; decrease in strength and elasticity of muscles; and decrease in elasticity and strength of ligaments. Although you cannot totally halt the progress of these effects, they can be slowed by regular exercise, knowing the proper way to lift and move objects, proper nutrition, and avoidance of smoking.
Age - "Wear and tear" and inherited factors will cause degenerative changes in the disks, called degenerative disk disease, and arthritic changes in the small joints. These changes occur to some degree in everyone. When severe, they can cause low back stiffness and pain. Arthritic bone spurs and inflamed joints can cause nerve irritation and leg pain. Almost everyone develops "wear and tear" changes in their low back as they age, although for most people it causes little pain or loss of function.
Osteoporosis and Fractures - All bones lose bone strength over time and the lumbar vertebrae, particularly in postmenopausal women, can be fractured or compressed from a fall or even from the stress of lifting or everyday activities.
Protruding Disk - The disk is composed of a soft center or nucleus, which, in children and young adults, is jelly-like. The nucleus is surrounded by a tougher outer portion called the anulus. With normal aging, the nucleus begins to resemble the anulus. During middle-age, fissures or cracks may occur in the disk. These may be the source of back pain. If the crack extends out of the disk, material from the disk may push out or rupture. This often is referred to as a herniated or slipped disk. If the protruded disk presses a nerve, it may cause pain in the leg.
WHAT IS THE BEST TREATMENT?
Most low back pain can be safely and effectively treated following an examination by your doctor or specialist and a prescribed period of activity modification and some medication to relieve the pain and diminish the inflammation. Although a brief period of rest may be helpful, most studies show that light activity speeds healing and recovery. It may not be necessary for you to discontinue all activities, including work. Instead, you may adjust your activity under your doctor's guidance.
Once the initial pain has eased, a rehabilitation program may be suggested to increase your muscle strength in your low back and abdominal muscles as well as some stretching exercises to increase your flexibility. Weight loss if you are overweight, and quitting smoking if you are a smoker, also will decrease the chances of a recurrence of your low back pain. The best long-term treatment is an active prevention program of maintaining your physical condition and observing proper lifting and postural activities to prevent further injuries.
WHEN IS SURGERY NEEDED?
Most low back pain, whether acute or chronic, almost always can be treated without surgery. The most common reason for surgery on the lower back is to remove the pressure from a "slipped disk" when it causes nerve and leg pain and has not responded to other treatments. Some arthritic conditions of the spine, when severe, also can cause pressure and nerve irritation, and often can be improved with surgical treatment.
WHAT IS THE LOWER BACK?
- five bones called lumbar vertebrae
- stacked one upon the other, connecting the upper spine to the pelvis
- six shock absorbers called disks
- acting both as cushion and stabilizer to protect the lumbar vertebrae
- spinal cord and nerves
- the "electric cables" which travel through a central canal in the lumbar vertebrae, connecting your brain to the muscles of your legs
- small joints
- allowing functional movement and providing stability
- muscles and ligaments
- providing strength and power and at the same time support and stability
The normal effects of aging that result in decreased bone mass, and decreased strength and elasticity of muscles and ligaments, can't be avoided. However, the effects can be slowed by:
- exercising regularly to keep the muscles that support your back strong and flexible
- using the correct lifting and moving techniques; get help if an object is too heavy or an awkward size
- maintaining your proper body weight; being overweight puts a strain on your back muscles
- avoid smoking
- maintaining a proper posture when standing and sitting; don't slouch