Many people have the experience of low back pain, and when complaining about the pain caused by lumbar spondylosis, they forget to pay attention to the causes of lumbar spondylosis formation, because avoiding the causes is the best way for us to stay away from lumbar spondylosis. There are many causes of lumbar pain, such as acute lumbar sprain, chronic lumbar strain and lumbar disc herniation, but the symptoms of lumbar pain caused by different etiologies are different. The doctor is not always able to point out the cause of the patient’s pain. But the doctor will try to make sure that your symptoms are not caused by a serious disease, such as cancer or a spinal cord infection. The causes of the formation of lumbar spondylosis can generally be divided into intrinsic and extrinsic factors, etc. 1. Degeneration Degenerative changes can occur in the intervertebral discs, which are porous and flexible and strong during childhood. The nucleus in the middle of the disc contains a lot of water. This gives the disc the ability to absorb shocks and thus protect the spine. The first changes in the disc as we age are that the annular bands around the nucleus become weaker and begin to have small cracks and wear. The body uses scar tissue to repair the cracks. However, the scar tissue is not as strong as the original tissue. Tearing of the annulus is one of the causes of pain: (1) There are pain receptors at the outer edge of the annulus. Pain occurs when the outer edge of the annulus is torn; (2) inflammation caused by the tear can also produce pain. Over time, the intervertebral disc begins to lose water and it becomes dry. As a result, the vertebrae begin to move closer to each other. If the disc continues to degenerate, the vertebrae narrow in spacing, which puts pressure on the small joints at the back of the spine. When these joints are squeezed together, the articular cartilage is subjected to additional stress. These extra stresses can damage these joints. Over time, this can lead to inflammation of the small joints. Thus degenerative lesions of the discs, facet joints and ligaments cause the spine to become unstable, and the ensuing additional movement of the spine can add to the wear and tear on the spine. As a result, the annulus is subjected to more and more tearing. The nucleus pulposus may be pushed into the spinal canal through the torn annulus. This is called a disc herniation or disc rupture. The extruded disc can compress the spinal nerve. The disc releases enzymes and chemicals that cause inflammation. The combination of nerve compression and inflammation caused by the chemicals released from the disc causes pain. Degeneration continues to progress and bone spurs grow around the facet joints and discs. No one knows exactly why bone spurs develop. Most doctors believe that bone spurs appear as the body tries to limit excessive movement between spinal cord segments. These spurs cause problems by pressing on the nerves that pass through the nerve foramina. The pressure around the irritated nerve roots causes pain, numbness and weakness in the lower back, buttocks, lower extremities and feet. The spinal cord segments eventually become stiff and inflexible. Thickened ligaments and facet joints, scarred, dehydrated disc tissue and protruding bone spurs prevent normal movement. Hard joints are generally less likely to cause pain than overly mobile joints, so this stage of degeneration may relieve some people’s pain. 2. Neurogenic pain (1) Mechanics of pain Mechanics of back pain is caused by strain on the lumbar spine. This pain is essentially similar to a machine that is beginning to wear out. Mechanic pain usually starts with degenerative changes of the intervertebral discs. This is when the discs begin to disintegrate, the spacing between the vertebrae narrows, and inflammation develops in the facet joints. The pain of mechanics is usually aggravated after will activity. The mechanical pain is usually in the back, but may extend to the hips, thighs and knees. Mechanical back pain usually does not cause a feeling of weakness or numbness in the legs and feet. (2) Neurogenic pain Neurogenic pain means pain caused by nerve damage. Neurogenic pain occurs because of inflammation or compression of a spinal nerve. This can occur when a disc herniates or a nerve is compressed. Recently it has been recognized that even if the nerve is not directly compressed, pain can occur when the nerve becomes inflamed by chemicals released from a ruptured disc. Neurogenic symptoms are more worrisome than mechanical pain because neurogenic pain can cause a feeling of weakness or numbness in the limb. Nerve compression causes symptoms in the innervated area, not in the lumbosacral region. This is because pressure on the spinal nerves affects structures outside the spine, such as muscles. So a person may not have an injury to the back, yet may feel pain, numbness, or weakness in the legs or feet. This indicates a problem with the body’s nervous system. Neurological stress affects the body’s functions. Muscle weakness, slowed reflexes, pins and needles and numbness in the innervated area. 3. Conditions of the spine (1) Tearing of the annular ligaments Similar to hair turning gray, our intervertebral discs change as we age, and the earliest stages of degeneration are perhaps due to tears of the annular ligaments. These tears stem from wear and tear over a period of time, or they may stem from a sudden injury to the disc. Tears of the annular ligament may cause back pain straight scar tissue repair damage. (2) Internal disc splitting Multiple tears of the annulus can lead to weakened disc protection. Disintegration of the disc can be a source of pain because it loses the ability to absorb shock between vertebrae. This problem causes inflammation of the disc and surrounding tissues, causing primarily mechanical back pain. (3) Disc herniation A weakened disc may rupture or herniate. If the annular ligament ruptures or tears, the nucleus pulposus material can extrude, or protrude. If a herniated disc presses on a spinal nerve it usually causes problems. Chemicals released from the disc can also cause inflammation of the nerve roots, causing pain in the area innervated by the nerve. This pain is called sciatica. Even normal intervertebral discs can rupture. Heavy, repetitive bending and twisting and lifting can put excessive pressure on the discs, causing tears in the annular ligament and rupture of the nucleus pulposus into the spinal canal. (4) Microarthritis Small joints link the vertebrae together along the back of the spine. They do not carry much weight, however if the disc loses its height, the vertebrae above this disc will press against the vertebrae below the disc, which can cause the facet joints to press together. Small joints covered with articular cartilage, just like other joints in the body covered with articular cartilage, can develop osteoarthritis as the articular cartilage continues to wear away. The additional pressure on the small joints accelerates the degeneration of the facet joints. The swelling and inflammation that occurs when small joints become inflamed can be a cause of low back pain. (5) Spinal cord segmental instability Spinal cord segmental instability means that the vertebrae within a spinal cord segment are moving outside of their normal range. Often the supporting ligaments around the vertebrae have been stretched. Segmental instability also includes a condition in which one of the vertebrae slides relative to the next vertebrae in its line. This condition is called slipped vertebrae. Whatever the cause, the extra movement of the spine creates problems. Inflammation and pain in the tissues surrounding the spine due to excessive movement can cause mechanical pain, and if the extra motion squeezes a spinal nerve it can produce symptoms of neurogenic pain. (6) Spinal stenosis Stenosis means being closed. Stenosis of the spine means that the tissue within the spinal canal is closed or compressed. The spinal cord terminates at L2 below this level and the spinal canal contains only the spinal nerves that travel to the pelvis and legs. When spinal stenosis occurs, the spinal nerves within the spinal canal are compressed. In this case, the pressure affects the function of the nerves, causing problems such as pain and numbness in the buttocks and legs, and muscle weakness. Because these nerves innervate the bladder and rectum, weakened muscles can affect control of the rectum and bladder. (7) Foraminal stenosis The tunnel through which the spinal nerves pass out of the spinal canal between the vertebrae is called a neural foramen. Any cause of narrowing of this tunnel can squeeze the spinal nerve, a condition called foraminal stenosis. When the disc disintegrates and compresses, the upper vertebrae press against the lower vertebrae and the space around the nerve root narrows, squeezing the nerve root. Arthritis in the small facet joints causes bone spurs to form and extend into the foramina to further compress and irritate the nerve. Foraminal stenosis can cause mechanical pain with neurogenic pain.