Causes of back pain are often grouped into broad categories such as:

• Traumatic: the result of an injury
• Degenerative: caused by wear and tear
• Other causes: which include tumors, infection, and autoimmune disorders

Traumatic

A traumatic cause of back pain is the result of an injury. An injury is perhaps the most common cause of back pain. Some injuries are minor and resolve spontaneously on their own and others require medical attention and a prolonged recovery.

• Muscle strain: also known as a pulled muscle, a muscle strain refers to damage to the muscle or its connecting tendons. This can be caused by lifting a heavy object or twisting awkwardly. These are typically minor injuries that heal with rest and medications.
• Fracture: a fracture is a broken bone and may be the result of a fall, or high impact injury like a car accident. In older people with osteoporosis (decreased bone density) fractures can occur with minimal trauma. Depending on where the vertebrae is broken, a fracture can be treated with rest alone, bracing, but can sometimes require surgery.

Degenerative

Degenerative causes of back pain refer to wear and tear on the spine. This is often age related, or due to overuse and repetitive injury. Chronic back pain is often caused by degenerative changes.

• Canal Stenosis (narrowing): the spinal cord and spinal nerves pass through canals within the spine. These can narrow due to bony overgrowth (osteophytes), thickening of ligaments (ligamentum flavum hypertrophy), or because of a herniated intervertebral disc.
• Herniated disc: The intervertebral discs can slip, protrude, or rupture which can result in canal narrowing and compression of the spinal cord or nerve roots.
• Degenerative disc disease: refers to wear and tear on the intervertebral disc. The disc can be thought of as a gel filled sac (nucleus pulposus) with a fibrous outer layer (annulus pulposus) that acts as a shock absorber. Overtime, the gel-like center can dry out and the outer layer may break down leading to pain.
• Spondylosis: is a general term that refers to age related wear and tear, or degeneration, of the spine.
• Spondylolisthesis: is when one of the bones of the spine, called a vertebrae, slips forward or backwards from its normal position.

There are other causes of back pain that are neither due to injury or degenerative changes in the spine.

• Tumor: An abnormal growth that may be benign or cancerous. Treatment may be surgery, radiation, chemotherapy, or a combination.
• Infection: An infection can affect the bones (osteomyelitis), the discs (discitis), or the space surrounding the spinal cord (epidural abscess).
• Auto-immune disorders: Autoimmune disorders occur when your immune system misidentifies healthy cells as foreign and attacks them by mistake. Example disorders are rheumatoid arthritis and ankylosing spondylitis.

Sometimes, the sensation of back pain is actually unrelated to a disorder of the spine. Examples include:

• Kidney stone or kidney infection (pyelonephritis)
• Aortic dissection or aortic aneurysm – life threatening conditions affecting the aorta, which is the large blood vessel that transports blood away from your heart.

An evaluation by a medical professional is highly recommended to ensure a proper diagnosis.