The spine is divided into five regions – cervical, thoracic, lumbar, sacral, and coccyx – and is comprised of bones (vertebra) stacked one on top of the other. From each vertebral body extends additional bones (the pedicles and lamina) that form the cylindrical canal that protects the spinal cord. Between each vertebra is a disc and between each pedicle is a joint. This entire column is held together by ligaments in much the same way as the joints of the finger are constructed. Large bundles of muscle run parallel to the spine.
So what can cause back pain? Well, a lot of things but two very common causes of low back pain are muscle strain and tissue inflammation. Just like arthritis can cause pain in, say, a finger joint, it can cause pain in the back. Because most arthritis is due to inflammation, symptoms often respond to anti-inflammatory medications such as Aleve or ibuprofen. And just like you can strain an ankle, you can injure the ligaments in the back by overexertion. Ankle strains are treated by splinting to reduce motion. When the back is strained, the muscles try to splint it by tightening. But this, in turn, can cause more pain. Unlike the finger or ankle, the back is difficult to splint even with corset-like braces. Once injured, a vicious cycle begins with pain causing spasm causing more pain causing more spasm. When this happens, muscle relaxants can be used for a short period of time. Other physical treatments such as massage and heat can help relieve spasm.
Age also extracts a toll on the back. Just like the joints in our knees can, with age, lose cartilage, so do the (facet) joints in the spine. The water content and elasticity of our discs decreases which results in a loss of space between vertebrae. Because the nerves to our limbs exit the spinal canal on their way to our muscles, any loss of space between the vertebrae runs the risk of pinching these nerves. In some cases the disc may compress a nerve, but instead of producing back pain this usually results in pain that radiates down the leg to the foot.
Diagnosis and treating the myriad causes of back pain can be frustrating for both patient and physician. Although modern imaging techniques, such as CT and MRI, may be excellent for showing us the anatomy of the spine, they often can’t show us the cause of pain. Pain, after all, is a symptom of other problems.
So be kind to your back - lift properly, keep your back muscles strong, and don’t over do manual work.