Back Pain Causes
Most back pain is due to a strain, a sprain or an injury that affects the ligaments or muscles of the spine. A relatively small percentage of back pain is due to one of the various forms of arthritis, such as degenerative disc disease, spinal stenosis, osteoarthritis, ankylosing spondylitis, psoriatic arthritis, enteropathic arthritis, polymyalgia rheumatica.
Strains or Sprains
When ligaments in the back are severely strained or torn, usually from a sudden injury, the result can be pain. The pain of a sprain can be severe, localized to one spot in the back or more generalized all of your back and in nearby areas of the body.
Sometimes overworked muscles of the back (and elsewhere) go into spasm – painful, involuntary contraction, similar to a charley horse (a cramp, usually occurring in the calf muscle). While spasms are painful, they are the body's way of protecting itself from the underlying problem. When muscles are in spasm, they become painful and rigid, so that you are temporarily unable to use or damage them further.
Ruptured or Herniated Discs
When discs are weakened, the hard outer covering can rupture, allowing the squishy center to bulge out causing pressure and irritation to nearby nerves.
Fractures of the vertebra may be caused by a trauma, but more often are the result of osteoporosis, which weakens the vertebrae and causes them to crumble. These are called compression fractures.
Pain also may occur after a period of strenuous activity or after a period of inactivity, such as lying in bed for an extended time due to illness.
Being overweight puts added strain on the back and stomach muscles, causing those muscles to stretch and weaken. Lack of support can lead to poor posture, which shifts the body out of balance and cause or worsen back pain. Sometimes, the pain may be a result of poor posture regardless of how much a person weighs.
Stress may also be a factor because people react to stress in different ways. Some people tighten their back muscles when they are worried or tense, which can make existing back problems worse.
Sometimes back pain can be the result of a problem not located in the back. Possible causes include:
- Kidney stones or kidney infections. Because of the kidneys' location in the lower back, problems with the kidney may be felt as back pain.
- Pregnancy. Weight gain from pregnancy can both stress the back and stretch and weaken muscles that support the spine.
- Obesity. Being overweight or obese, particularly if excess weight is carried in the abdomen, places stress on back muscles, causing pain.
- Endometriosis. This is a condition in which the endometrial tissue (tissue that lines the uterus) migrates from the uterus and deposits on other organs and structures. Pain from endometriosis is often felt in the abdomen and back.
- Aortic aneurysms. In rare cases, the aorta (the body's main artery that originates at the heart and runs down the body just in front of the spine) develops an aneurysm, a balloon-like swelling in the artery's muscular wall. If the wall ruptures or causes compression of the blood vessels that run off it, the result can be pain that is felt in the chest, abdomen and/or lower back. This is a medical emergency, requiring immediate treatment.
- Tumors. In rare cases, tumors – either malignant (cancerous) or benign (not cancerous) – can affect the tissues of or near the spine, causing pain.