Soft tissues around the spine also play a key role in the health of the back. A large, complex group of muscles work together to support the trunk and hold the body upright. They also allows the trunk to move, twist and bend in multiple directions.
Three types of back muscles that help spinal function are the:
- Extensor muscles. Attached to the back of the spine, these muscles allow us to stand and lift objects. They include the large muscles in the lower back (erector spinae), which help hold up the spine, and gluteal muscles.
- Flexor muscles. Attached to the front of the spine, these muscles include the abdominal muscles. They allow us to flex, bend forward, lift and arch the lower back. When the abdominal muscles are weak, the muscles that allow us to bend at the hip get tighter, increasing the curve at the lower back.
- Oblique muscles. These are attached to the sides of the spine. They help us rotate the spine and maintain proper posture.
Muscles can cause back pain when:
- The facet joints or other boney parts of the spine become injured or inflammed, which can cause the large muscles of the back to contract involuntarily (spasm)
- Chronic stress can causes the muscles to tighten up, using up energy that is needed to hold the spine upright
- Tight muscles in the back of the thighs can cause changes in the position of the pelvis, affecting spine movement