Your spine is made up of interconnected bones, nerves, tendons, muscles, and ligaments that work together to support your body and enable movement.
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.
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.
The building blocks of your spine are your vertebrae, which are comprised of bone (above is a picture of a single vertebra).
Your cervical spine (neck) is comprised of 7 vertebrae.
Your thoracic spine (upper back) has 12 vertebrae.
Finally, your lumbar spine (lower back) has 5 vertebrae.
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).
Segments of your spine are named for their upper and lower vertebrae. For example, the above segment is called the C6-C7 segment.
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.
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.
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:
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.
Over time, your discs can degenerate (and may become a source of pain). This condition is known as 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.
Pain may radiate along the path of the nerve root into your arms or legs; depending on which nerve is irritated.
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.
If these joints are either too loose or too tight, back pain may result. This condition is known as 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.
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