What Causes Lower Back Pain?
Approximately eighty percent of people will have low back pain at some point in their lives. The good news is that very few people who feel pain in their low back have a serious medical problem that requires surgery. Ironically, the severity of the pain is often unrelated to the extent of physical damage. Muscle spasm from a simple back strain can cause excruciating back pain that can make it difficult to walk or even stand, whereas a large herniated disc or completely degenerated disc can be completely painless. Most low back pain symptoms will get better with time (anywhere from 2 - 12 weeks) and non-surgical care. There is usually no single identifiable cause for an episode of back pain. Most back pain comes from the soft tissues of the spine (ligaments, muscles and joints.) One of the most common factors in back pain is that your spine is out of align causing excess fatigue to your joints, muscles and connective tissue. This can be triggered by prolonged sitting or standing in a poor position, or prolonged bending. The problem can also be made worse by heavy or repetitive lifting. Many conditions can cause back and neck pain, ranging from injury to infection to simply twisting the wrong way. An injury sustained in an automobile, skiing, diving or other type of accident may cause damage to bone, muscles, tendons, ligaments, joint capsules, and nerves.
Acute pain in the lower back that does not extend to the leg is most commonly caused by a sprain or muscle tear, usually occurring within 24 hours of heavy lifting or overuse of the back muscles. The pain is usually localized, and there may be muscle spasms or soreness when the doctor touches the area. The patient usually feels better when resting. A strain is the result of a heavy load or sudden force applied to the muscles before they are ready for activity. The muscle essentially rips, along with the blood vessels within the muscle tissue. This may cause bleeding into the injured area. It can take up to two to three hours before sufficient bleeding or irritation sets in to produce significant pain. This can help explain why many people often can tolerate finishing the task at hand, only to suffer from intense pain later. Sprains refer to an overstretching of one or more of the ligaments of the back. The ligaments can be stretched beyond their natural integrity and in some cases can completely tear. It is common to have both ligament sprains and muscle strains occurring together. This is especially the case in severe falls and motor vehicle accidents.
Degenerative joint disease - The joints that allow mobility and stability are subject to wear and tear. Facet joints allow movement of the spine. These consist of two knobs, or facets, that meet between each vertebra to form a joint. As facet joints degenerate, they may not align correctly, and the cartilage and fluid that lubricates the joints may deteriorate. Bone then rubs against bone, which can be very painful. In degenerative joint disease (also called osteoarthritis), the shiny, smooth cartilage that lines the joint wears away, leaving bone to rub on bone, a painful situation. Degeneration of the disc is called spondylosis. Spondylosis can be noted on x-rays of the spine as a narrowing of the normal "disc space" between the vertebrae. It is the deterioration of the disc tissue that predisposes the disc to herniation and localized lumbar pain ("lumbago") in older patients. Degenerative arthritis (osteoarthritis) of the facet joints is also a cause of localized lumbar pain that can be detected with plain x-ray testing. These causes of degenerative back pain are usually treated conservatively with chiropractic care, intermittent heat, rest, rehabilitative exercises, and supplements to relieve pain, muscle spasm, inflammation as well as others to increase the cartilage between the bones.
Sacroiliac Syndrome - Your Sacroiliac or SI joints sit on either side of your tailbone at the base of your spine. They are large joints which are important in everyday life because they move when you walk and they dampen the shock that each step places on your body. Think of them as shock absorbers. But they can become locked which causes a generalized dull ache in the low back which may also be felt in the buttocks or even down the back of the thigh. Protective muscle spasm may also occur which limits normal activity; however, there are no muscles that actually cross the SI joints. That is one of the reasons this type of low back pain does not respond to stretching and exercise alone and often requires chiropractic adjustments to releive the pain.
Facet Joint Syndrome - This is a very common cause of lower back disorders. Facet joints occur in pairs at the back of each vertebra and they prevent excessive motion of the spine. When these joints are exposed to excessive trauma - from sports, work, normal aging, etc. - they can become inflamed and motion may be restricted at a particular level of your spine. This may cause low back pain or even pain which is felt in the back of the thigh. Once again, protective muscle spasm may further complicate the situation.
Ruptured Discs - The term "slipped disc" is actually a misnomer which does not really occur. Each vertebra is separated from its neighbour by a cushioned disc. Each disc is tightly attached to its neighbouring two vertebrae and can therefore, never "slip" out of place. What can happen, though, is that a disc which has weakened due to repetitive injury or small traumas may rupture. This allows some of the soft center material to leak out through the tough outer casing into the vertebral canal. This "leak" can press on the nerves which go to your legs, causing sharp pain down to your toes. This leg pain is often worse than the back pain itself. This is a less common form of back pain than SI or Facet Joint Syndrome, but it is somewhat more serious. If you are concerned about the possibility of a ruptured disc, look for these symptoms:
deep dull ache in the lower back and/or buttocks
leg pain with numbness, tingling or weakness
body tilts to one side to relieve the pain
movement is restricted and slow
leg pain with coughing, sneezing or straining
A Word About Sciatica - Many people are confused about the term "Sciatica". Sciatica simply means pain down the leg along the path of the sciatic nerve. This is not a diagnosis! it is only a description of a symptom associated with certain types of back pain. In other words, the term sciatica doesn't tell you where the pain is coming from, only that it includes some leg pain. You can't properly treat the symptom of sciatica if you don't know exactly where it's coming from. Pain is often experienced along the large sciatic nerve, from the lower back down through the buttocks and along the back of the leg. It may occur with or without lower back pain. However, it is most commonly caused by peripheral nerve root compression from intervertebral disk protrusion or intraspinal tumor. Compression may be within the spinal canal or intervertebral foramen by disk protrusion, tumor, or bony irregularities (e.g., osteoarthritis, spondylolisthesis). The nerves can also be compressed outside the vertebral column, in the pelvis or buttocks. It could also be related to a disc herniation, facet problems, SI joint problems, piriformis syndrome, etc. If you've been told you have sciatica, that's only part of the story. You need to find the cause of the sciatica. The focus of a chiropractic examination is to find the root cause of your problem, not just identify the symptoms. From there, we can formulate a treatment plan to correct your problem. Remember - treat the cause, not the symptoms.
Spinal stenosis - Narrowing (stenosis) of the spinal canal can be caused by calcium deposits in ligaments, degenerative joint disease or disk disease, or it may be present since birth. Any of these problems alone or in combination can lead to pressure on the spinal cord or a nearby nerve, causing pain. Conditions that cause spinal stenosis include infection, tumors, trauma, herniated disc, arthritis, thickening of ligaments, growth of bone spurs, and disc degeneration. Spinal stenosis most commonly occurs in older individuals as a result of vertebral degeneration. Spinal stenosis occurs as intervertebral discs lose moisture and volume with age, which decreases the disc spaces. Even minor trauma under these circumstances can cause inflammation and nerve root impingement, which can produce classic sciatica without disc rupture. Spinal stenosis is a less common mechanism for sciatica that results from lumbar spinal canal narrowing, causing pressure on the sciatic nerve roots (or rarely the cord) before their exit from the foramina. It may mimic vascular disease by simulating intermittent claudication. The disorder occurs in middle-aged or elderly patients.
Spondylolisthesis - Spondylolisthesis is a relatively common condition, especially among older persons, in which one vertebra slides forward on another. When a tiny defect or fracture in the bones at the back of the vertebrae is also present, the condition is called spondylolysis. In either case, the spinal cord or nerves leaving the cord can be compressed, causing pain in the back or legs. Spondylolisthesis is a condition in which one vertebra slips forward on the one beneath it. It may result from a number of causes, including trauma to the spine or osteoarthritis (wear and tear) of the spine, or it may have been acquired from birth. The amount the vertebra has slipped forward on the one beneath it may be minimal or very significant. There may be no symptoms or there may be back pain and the back may feel stiff. If the slip has caused pressure on a nerve root, pain may be felt in the buttocks or thigh. With a major slip, an increase in the bend of the lower back can be noticed (called increased lordosis). Treatment depends on the severity of the condition and the symptoms. This may range from simple exercises and physical therapy to spinal fusion (hyperlink glossary) to stabilize the spine.
Osteoporosis with compression fracture - By itself, osteoporosis is painless, but it increases the risk of fracture of the hip, wrist and vertebrae. The fracture itself or the resulting abnormal curvature of the spine or pressure on nerves may be a source of pain. In osteoporosis - a progressive disease that commonly affects postmenopausal women - the bones become weaker and more porous. Although osteoporosis is painless, it increases the risk of fracture of the hip, wrist and vertebrae. Vertebral fractures themselves may be painful, as can be the resulting abnormal curvature of the spine or pressure on nerves.
Pregnancy - A woman's body undergoes significant hormonal and physical changes during the nine months of pregnancy. For most women, this can lead to back pain as an unavoidable side effect during this time.