Causes of Lower Back Pain
It is often stated in conventional literature that the cause of lower back pain cannot be precisely identified. This perspective derives from a mechanistic, non-integrated view of the body which has been our legacy since the scientific revolution. When the body is viewed as a collection of isolated parts rather than an elegant, integrated whole, the causes of lower back pain remain a bewildering thing.
However, a holistic view of the body can begin to sort out the confusion. By evaluating the relationship between the body's overall structure in gravity and it's function in movement, the causes of lower back pain begin to reveal themselves.
A holistic perspective guides us to one of the most overlooked sources, not only of lower back pain, but chronic pain in general. That source is skeletal muscle.
As Drs. Janet Travell and David Simons made explicitly clear in their exhaustive two-volume work, Myofascial Pain and Dysfunction: The Trigger Point Manual, a vast proportion of chronic pain in the body is not due to problems with damaged nerves, disrupted bursae, and degenerative joints, but dysfunction in the soft tissue, especially skeletal muscles.
The cause of lower back pain can be broken down into five primary problems which interconnect with one another. The following breakdown is adapted from the St. John Neuromuscular Therapy training, a method of postural analysis and clinical massage therapy focused on musculoskeletal alignment and treating compensatory muscular patterns.
Five Primary Problems
1) Ischemia (pronounced: Iz skeem ee ah)
The first cause of lower back pain is ischemia. "Ischemia" means lack of blood. Without adequate blood to provide nutrients and oxygen, soft tissues such as muscles, tendons, ligaments, and fascia build up lactic and other toxins and become painful. Ischemia occurs when muscles are chronically contracted over a period of time. The most prevalent cause of lower back pain, by far, is muscular strain and spasm due to ischemia.
2) Trigger Points
The second cause of lower back pain is trigger points. A trigger point is an area of the soft tissue which, after chronic contraction and reduced blood flow, becomes an area of high neurological activity. For example, fibers in an ischemic muscle (a muscle with low blood) can become an active trigger point in response to biochemical changes in the tissue. Active trigger points cause referred sensation to other parts of the body. That sensation can be pain, tingling, numbness, thermal sensations (hot or cold), weakness, a general achy quality, or the feeling that "it just doesn't feel right." For example, you might have a trigger point in a muscle of your lower back which refers sensation down into your buttocks, or even down the leg. This is NOT same thing as the referred pain caused by nerve compression and nerve entrapment which will be covered next.
3) Nerve Compression and Nerve Entrapment
The third cause of lower back pain is nerve compression and entrapment. Nerve compression is the pressure put on a nerve by a bone or an intervertebral disc. Nerve compression occurs when the spine becomes misaligned for some reason (faulty movement patterns, injury, chronic muscular tightness) and one of the discs between the vertebrae get squeezed on one side so that it bulges out the other side. If the bulging puts pressure on a spinal nerve, then you've got pain! Nerve entrapment is when a nerve is caught or pinched by the soft tissues. For example, the sciatic nerve (the largest nerve in the body) runs down through the buttocks and can become entrapped by the piriformis muscle when that muscle is very tight. This can result in pain down the back of the leg.
4) Structural Imbalance, aka Postural Distortion
The fourth cause of lower back pain is structural imbalance or postural imbalance. In a sense, this issue is the most significant of all. The reason for that lofty status is due to the fact that structural imbalance is often the root problem responsible for ischemia, trigger points, and nerve compression or entrapment.
If the body is distorted off its center line of gravity, compensating muscular patterns can result. To illustrate the point, put your elbow on the table in front of you with your forearm pointed straight up to the ceiling. Now imagine you've got a bowling ball resting in your palm. If your forearm is completely straight up and down, the weight of the bowling ball will be supported by the bones of your forearm. Theoretically, you could hold that bowling ball there indefinitely.
But if you shifted off that center line, even a tiny bit, then the muscles of your arm would have to engage in order to hold up the bowling ball. Even the strongest human in the world wouldn't be able to hold that ball there for long. This is precisely what can happen with your body. If your alignment is off such that your head is not centered over your shoulders over your hips over you feet, then the core muscles of your body must perpetually engage in order to hold your body up!
5) Dysfunctional Biomechanics
The fifth cause of lower back pain is dysfunctional biomechanics. This is often a secondary result of structural imbalance and is evidenced by faulty movement patterns. For example, if you've got nagging lower back pain you might hold your body in a restricted way, walk differently, or reach for things with limited range of movement. It's logical to do that, and not recommended to fight against your body's self-imposed limitations. It's trying to protect you from pain. Until the structural imbalance is addressed, and the pain is relieved, there's wisdom in those limits. However, repetitive movements can become patterned into your nervous system such that, even after structural and muscular problems have been eliminated, you still move in a limited, protective way. This can revive structural and muscular imbalances. That's why even a minimum regime of daily stretches can be vital to full recovery.