One of the reasons that it is difficult to determine what causes back pain is that there are many structures that can be injured in the lower back (lumbar) region.

You can injure the muscles, the ligaments, the intervertebral discs, the nerve roots, the cartilage that lines the joints, the bones in the lower back, over even the spinal cord. And of course you can injure multiple structures in the lumbar region.

In addition, you can get referred pain from the hip or the pelvis, and you can even get referred pain from internal organs such as the kidneys.

Back Pain can arise from autoimmune diseases, chronic wear and tear, or trauma or injury.

Okay, I think you get the point that the lower back is complex.



Now, I want to try to simplify back pain and focus on Mechanical Back Pain (associated with osteoarthritis) which one type of problem that affects the lower back.

Mechanical Back Pain or Arthritis primarily affects the cartilage that lines the joints between the vertebrae of the lower back. It is referred to as mechanical back pain because compression (a mechanical phenomenon) is generally the cause of pain.



When the joints get compressed, the cartilage wears away. When the cartilage wears away, your joints get stiff and achy.

Here are some other factors that can contribute to extra pressure on the joints of the lower back.

A sedentary lifestyle and sitting in front of a computer puts extra pressure on the joints of your lower back.

In the American society, one of the major causes of compression in the lower back is sitting (especially in front of a computer). When you sit, your upper body weight is supported only by your lower back compared to when you're standing your ankle, knee, and thigh muscles take some of the pressure off your lower back.

Bad Posture puts extra stress on the lower back. When your body is not in good alignment, you will have more pressure in the area that is out of alignment and you will also have less stability in that area. Poor Stability and Increased pressure from bad posture may be one contributor to chronic lower back pain.

Weak Abdominal Muscles can increase the pressure on the lower back. The abdominal muscles help to maintain the position of the pelvis and lower back and stop the back from arching excessively. Weak abdominal muscles can be one contributor to chronic lower back pain.

Weak Lower Back Muscles can increase the pressure on the lower back. The lower back muscles just like the abdominal muscles play a major role in stabilizing the lower back. Weak lower back muscles can be a contributor to chronic lower back pain.

Poor Flexibility can increase the pressure on the lower back. When your body is inflexible, it does not move efficiently. If your body is stiff in one area, extra pressure will be placed on another area to make up for the stiffness. Stiff hip, thigh, and back muscles can contribute to lower back pain.

Poor Exercise Technique and Poor Lifting Technique can increase the pressure on the lower back. Incorrect form during exercise and bad body mechanics during lifting will place extra stress on the lower back.

Above is just a quick and simple perspective on mechanical back pain. Prolonged sitting, poor posture, weak abdominal muscles, weak lower back muscles, poor flexibility, and incorrect exercise or lifting technique can all increase the pressure on the cartilage that lines the joints of the lower back.

As a physical therapist, I try to encourage people who suffer from a slightly achy lower back to get up from in front on the computer periodically to move around.

In addition, I encourage people to be mindful of their posture and exercise regularly to strengthen the abdominal and lower back muscles.

And lastly, I encourage people to stretch regularly and use good lifting technique to decrease the pressure on the lower back.