There are many important facts about low back pain to consider (Figure 1). Firstly, there is no definite etiology in 85% of the cases. 90% of patients with a single episode of low back pain return to work within 6 weeks, most patients get better with time. Low back pain is the second most common cause of work absenteeism. A history of low back pain is the single most important factor predicting future occupational low back pain. Also, persistent back pain, for more than 6 months, constitutes 4% of the cases. Disability is closely linked to compensation and litigation.

The least amount of pressure is measured with the patient lying supine. The highest disc pressure is measured while sitting and leaning forward 20° with a 20 kg load in their arms (Figure 2).

By keeping the weight of the load close to the body, this reduces the compressive forces placed on the lumbar spine (Figure 3). Yoga activities and exercises performed during sitting will probably lead to less pressure being place on the discs.

Physical Factors Which Lead to Low Back Pain
There are many different physical factors that can attribute to low back pain including lack of fitness, heaving lifting of objects, operating motor vehicles, prolonged sitting, operating vibrating tools, and history of cigarette smoking (Figure 4). Holding loads close to the body is important to help reduce compression forces on the lumbar spine. Smokers has a higher risk of low back pain because nicotine can cause disc degeneration.

Sports Related Activities Associated with Low Back Pain
Sporting activities may also play a large role in people developing low back pain. Golf can cause pain as a result of twisting, bad forward bending and overarching the spine during the swing (Figure 5). After the age of 40, you lose about 50% of your rotational movement of the spine. It is important to perform stretching and warm ups before starting the game.

Vibration caused by horseback riding increases the load on the discs (Figure 6). The back muscles work constantly to keep the posture straight. Caring for horses could be bad for the back due to the bending and lifting associated with their care.

Etiology
Virtually any structure in the spine can hurt. These structures include facet joints, intervertebral discs, spinal canal, sacroiliac joint, muscles, ligaments, nerves, hip joint/piriformis syndrome, and the trochanteric bursa.

Red Flags for Cancer
Bone cancer of the vertebral body may also occur (Figure 7). Some of the factors that may be associated with bone cancer are people over 50 years of age, pain at rest and night, unexplained weight loss, and a history of cancer. Bone destruction involving the pedicle is pathognomonic.

Red Flags for Infection
An infection in the vertebral body (discs) may also be a factor contributing to low back pain (Figure 8). The infections can occur due to diabetes mellitus, fever, intravenous drug abuse, urinary tract infection, and previous surgery.

Physical Examination
During the assessment, the physician will initially focus on the red flags (fractures, tumor, infection, or cauda equina). The signs and symptoms of cauda equina include back pain, bowel or bladder disturbances, bilateral leg pain and weakness, and saddle anesthesia (rectal and genital area sensory changes). In the absence of red flags, imaging studies are usually not helpful in the first 4-6 weeks. Intensive work up may not be necessary in the early stages of routine low back pain.

Treatment
Conservative treatment for low back pain is the first step in treatment. Bed rest is controversial and should not exceed 2-3 days. Pain control is used in different methods including NSAIDS, Medrol dose pack. Watch for NSAIDs toxicity; gastritis, visceral bleeding, platelet dysfunction, and renal dysfunction. Physical therapy should be utilized as soon as pain control is achieved. A soft brace or a corset may be used, but it usually does not help a lot, even with a thigh extension. A thigh extension will only restrict about 50-65% of the normal gross body motion. An epidural injection can be used and has up to a 50% success rate; this improvement is oftentimes short lived.

Patients sustaining chronic disabling occupational low back pain without any intensive rehabilitation will have different expectations about returning to work. 50% of people who are out of work for 6 months will return to work. If the person if off of work for 1 year, only 20% will return to work. Lastly, almost none of the people that are off of work for over 2 years will return to work.

The best treatment for acute low back pain is to continue with ordinary daily activities within the limits permitted by the pain. So, it seems that the best treatment for low back pain is for the patient to return to work.