Although a sudden movement or twist can trigger the onset of pain in the lower back, do not assume that the movement was to blame. On the contrary, back pain is most often the result of gradual stresses and changes in the spine, only to be finally triggered by a movement as simple as bending down to pick up a pencil. This is especially true with a herniated ("slipped") disk. Even the impact of a fall great enough to kill someone -- say a parachuting accident -- has shown not to cause sufficient damage to herniate a disk. The human spine is incredibly resilient to such impacts. It is the wear and tear, however, after years of lifts and twists can manifest into a sudden condition.
"Slipped" Intervertebral Disk
The spine consists of bony blocks known as vertebrae which stand atop one another from your neck to your tailbone. Intervertebral disks lie between the vertebrae and act as cushions of spongy tissue, providing moveable connections between the bones.
The term "slipped" is misleading because the disk does not actually move out of place. Herniation occurs when the outer ring of the disk -- the annulus fibrosus -- ruptures or distorts, allowing the jelly-like substance within the disk to protrude and damage surrounding structures. Depending on the area of rupture and the extent of nerve damage, several outcomes may ensue.
The sciatic nerve, which is especially vulnerable as a result of disk damage, can produce unpleasant feelings of numbness and tingling in one or both limbs when irritated. This is where the term "sciatica" comes from. Nerve damage can also cause weakness in leg muscles, which require nerve impulses for stimulation. Some of the nerve roots also supply the bladder and lower bowel -- damage here can lead to incontinence and is perhaps the only reason for immediate surgery.
Degeneration of the Spine
When we are young, our spines tend to be more flexible and supple -- but with time, the intervertebral disk becomes tough and fibrous, reflecting the wear and tear changes within the spine. These changes seem to affect disks in the lower back with greater frequency, as it is that part of the spine that carries the heaviest loads. The changes in and around the intervertebral disks are known as spondylosis, and are an attempt by the body to minimize further damage to the spine as we age. Although disk herniations become less frequent as a result of these changes (frequency of cases peak at around fifty years old), the hardening and compacting of intervertebral disks causes other concerns: movement is restricted and stiffness in the lower back often ensues.
By sixty years of age, almost everyone has some signs of wear and tear that are detectable by a health practitioner. That does not mean however, that younger people are immune. As early as twenty years of age, the spine can show early signs of wear and tear -- although at that age, changes in and around the spine are rarely significant enough to warrant concern.
Non-Specific Back Pain
Although some cases of back pain (like those listed above) can be correlated to a specific mechanical problem, most occur without any detectable irregularities within the spine. In fact, the causes of most people's back discomfort is widely unknown. After all, our aches and pains do not reveal the entire story. Pain, although a concern in its own right, is a response by our bodies and is not necessarily an indication of a precise mechanical problem. As mentioned above, we all feel pain differently and react to pain in different ways; many of us feel pain for different reasons. It cannot be emphasized enough that there is no objective means by which that pain can be understood.
Back pain sufferers are too often diagnosed and categorized according to their symptoms. Yet just as not all chest pains indicate the onset of a heart attack, back troubles can be linked to more than just the mechanics of the spine: anxiety, depression, and stress, to name a few. In fact, studies of workers in major corporations have shown that the best precursor to back pain is not physical condition, heredity or examination by a specialist, but rather job stress and anxiety. Seemingly, there is a lot more to back pain than the condition of the spinal column.
