Your spine is made up of interconnected bones, nerves, tendons, muscles, and ligaments that work together to support your body and enable movement.

Lumbar OsteoarthritisMany different structures in your spine can cause back pain, including your large nerve roots.
Watch:
Spine Anatomy Interactive Video

Our video walk-through can provide a helpful introduction to the anatomy of your spine, which in turn can help you better communicate with your doctors.

See Normal Spinal Anatomy

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If damage occurs to the bones, nerves, tendons, muscles, or ligaments that make up your spine, it can result in pain, neurological symptoms, and/or loss of mobility.

See Spinal Anatomy and Back Pain

The building blocks of your spine are your vertebrae, which are comprised of bone (above is a picture of a single vertebra).

See Vertebrae in the Vertebral Column

Your cervical spine (neck) is comprised of 7 vertebrae.

See Cervical Vertebrae

Your thoracic spine (upper back) has 12 vertebrae.

See Thoracic Spine Anatomy and Upper Back Pain

Finally, your lumbar spine (lower back) has 5 vertebrae.

See Lumbar Spine Anatomy and Pain

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Spinal Segments

Each segment of your spine is made up of three components. The first component is a bony, cylinder-shaped part of the vertebral segement called the vertebral body (shown above in purple).

The second component is the disc, which is comprised of cartilage (pictured above in purple).

See Spinal Discs

And the third component are the facet joints in your back (shown above in purple).

See Facet Joint Disorders and Back Pain

Segments of your spine are named for their upper and lower vertebrae. For example, the above segment is called the C6-C7 segment.

See All about the C6-C7 Spinal Segment in the Neck

Spinal cord and nerves

Your spinal cord runs in a canal from your neck down to your lumbar spine (lower back), and is protected by the bones in your spinal column.

See Spinal Cord and Spinal Nerve Roots

In your lumbar spine, your nerves branch out from your spinal cord and exit your spine. These nerves are called the cauda equina because they resemble a horse's tail.

See Cauda Equina Syndrome

These nerves exit each segment from small holes (shown above) called the foramen.

Pain and/or neurological symptoms can occur if these nerve roots are compressed. Compression may result from any of the following:

Pain and/or other symptoms that radiate along the pathway of a nerve is referred to as radiculopathy. But in your legs these symptoms are called sciatica.

See Cauda Equina Syndrome Symptoms

Spinal anatomy and disc pain

Pain and/or dysfunction may originate in the discs between your vertebrae (shown above in purple). Your discs act as shock absorbers, and also allow your spine to move and twist.

See All About Spinal Disc Problems

Over time, your discs can degenerate (and may become a source of pain). This condition is known as degenerative disc disease.

See Common Symptoms of Degenerative Disc Disease

If the soft inner portion of your disc leaks out (also referred to as a disc herniation), it can irritate a nearby nerve.

See Diagnosing Disc Problems

Pain may radiate along the path of the nerve root into your arms or legs; depending on which nerve is irritated.

See What Causes Hand Pain and Numbness?

Sacroiliac joint and tailbone

Another possible source of pain that is related to your spine is the sacroiliac joint.

The sacrum (shown above) connects the base of your spine with your pelvis at the sacroiliac joints.

See Sacrum (Sacral Region)

If these joints are either too loose or too tight, back pain may result. This condition is known as sacroiliac joint dysfunction.

See Treatment Options for Sacroiliac Joint Dysfunction

Your tailbone, or coccyx, sits below your sacrum and consists of several small bones. Tailbone pain may occur if any part of this area is damaged.

See Coccydynia (Tailbone Pain)

Spinal anatomy and medical emergencies

While many symptoms relating to your spine can be treated with conservative measures, certain (rare) symptoms require immediate medical attention. For example, any of the following symptoms that accompany pain in your lumbar spine should be treated as a medical emergency:

  • Loss of bladder and/or bowel control
  • Fever accompanied by increased pain that does not respond to common fever reducers
  • Unexplained weight loss accompanied by pain and neurological impairment

When Back Pain May Be a Medical Emergency

Learn more:

Cervical Nerves

Sacroiliac Joint Anatomy