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 or other type of accident can damage muscles, joints, ligaments, and vertebrae.
Overuse or underuse of the back is by far the most common cause of back pain that manifests as tightening or spasm of the muscles that connect to the spine. Inflammation and swelling often occur in the joints and ligaments, especially in the cervical and lumbar regions, as people age.
A herniated disc occurs when the nuclear pulposus, the inner material of the disc, pushes through a tear in the annulus fibrosus, causing nerve root compression.
The cervical and lumbar regions of the spine have the most mobility and the discs there are more likely to wear down or be injured. Ninety percent of disc herniations occur in the lower two lumbar vertebrae.
Spinal stenosis, narrowing of the spine, can cause spinal cord irritation and injury. 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.
A pinched nerve, or radiculopathy, occurs when something rubs or presses against a nerve, creating irritation or inflammation. Radiculopathy can result from a herniated disc, bone spur, tumor growing into the nerves, and vertebral fracture, and many other conditions.
Sciatica is a certain type of radiculopathy that involves inflammation of the sciatic nerve. Pain is experienced along the large sciatic nerve, from the lower back down through the buttocks and along the back of the leg.
A spinal tumor that originates in the spine (primary tumor) or spreads to the spine from another part of the body (metastatic tumor) can compress the spine or nerve roots and cause significant pain.
An infection that develops in the vertebrae (e.g., vertebral osteomyelitis), the discs, the meninges (e.g., spinal meningitis), or the cerebrospinal fluid can compress the spinal cord and result in serious neurological deterioration, if it is not diagnosed and treated immediately.
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.
Bone and joint diseases (e.g, osteoporosis [link to WHC osteoporosis], ankylosing spondylitis, osteoarthritis) can cause degeneration, inflammation, and spinal nerve compression.

Symptoms

Pain can be constant or intermittent. Intensity can vary from a dull ache to searing agony. The onset may be sudden, with or without apparent reason, or gradual. Most back pain resolves in a few days or weeks with or without treatment. However, some people have chronic pain that lasts months or years.

Severe pain lasting more than a few days without improvement may require medical attention. Anyone having difficulty passing urine; numbness in the back or genital area; numbness, pins and needles, or weakness in the legs; shooting pain down the leg; or unsteadiness when standing should see a physician immediately.

Localized pain is often described as aching, tight, stiff, sore, burning, throbbing, or pulling. The pain may worsen while bending, sitting, walking, or standing too long in one position. It may also be more prevalent at different times of the day, such as when a person wakes up in the morning.

Pinched nerves produce numbness or tingling, warm or cold sensations, and burning or stabbing pain that begins in the back and radiates down the leg (e.g., sciatica) or arm. Activities such as coughing, sneezing, or walking may increase pressure on the pinched nerve and aggravate the pain.

Compressed nerves causes numbness and weakness in the muscle associated with the nerve. The muscle may atrophy if the compression is not relieved. An infection affecting the spinal cord or nerves may produce fever and lethargy as well as symptoms of compression.