Soft tissues around the spine play a key role in lower back pain.
There is a large and complex group of muscles that work together to support the spine, help hold the body upright and allow the trunk of the body to move, twist and bend in many directions.
Lower back strain is acute pain caused by damage to the muscles and ligaments of the back. It is often referred to as a pulled muscle. The back is supported by a large, complex group of muscles that hold up the spine, including the extensor, flexor, and oblique muscles. The soft tissues surrounding the spine enable bending forward, lifting, arching, and twisting movements.
Lumbar muscle strain occurs when a back muscle is over-stretched or torn, which damages the muscle fibers. When one of the ligaments in the back tears, it is referred to as a sprain.
Movements that put stress on the back can result in pulled muscles. For example, lifting a heavy object, twisting while lifting, falling, or some sports could cause lumbar muscle strain.
Symptoms of lumbar muscle strain include sudden onset of pain, localized pain that does not radiate into the leg, and tenderness in the lower back.
Muscle strain can be accompanied by muscle spasms, as the body tries to stabilize the injury.
Acute pain from a lower back strain can resolve in a short amount of time, but low levels of pain or flare-ups can continue for weeks or months after the initial injury. After two weeks, back muscles can atrophy from lack of use and cause more pain.
There are many treatment options for lower back muscle strain, including exercise, which will prevent atrophy.
In This Article:
- Spinal Anatomy and Back Pain
- Vertebrae in the Vertebral Column
- Spinal Discs
- Spinal Cord and Spinal Nerve Roots
- Back Muscles and Low Back Pain
- Sacrum (Sacral Region)
Extensor, Flexor, and Oblique Muscles of the Back
Three main types of back muscles that help the spine function are extensors, flexors, and obliques.
- The extensor muscles are attached to back of the spine and enable actions like standing and lifting objects. These muscles include the large paired muscles in the lower back, called erector spinae, which help hold up the spine and the gluteal muscles.
- The flexor muscles are attached to the front of the spine and enable bending forward, lifting, and arching the lower back.
- The oblique muscles are attached to the sides of the spine and help rotate the spine and maintain proper posture.
The Role of Physical Activity and Exercise in Maintaining Muscle Health
Strengthening the back muscles helps reinforce support of the spine.
Back muscles, like any other muscle in the body, require adequate exercise to maintain strength and tone.
While the leg and thigh are used everytime we walk or climb a step, the deep back muscles and abdominal muscles are usually not actively engaged during everyday activity. Unless muscles are specifically exercised, back muscles and abdominal muscles tend to weaken with age.
See Back Exercises and Abdominal Exercise Recommendations
Physical therapy and exercise for lower back pain usually focus on strengthening the flexor, extensor, and oblique muscles. This in turn helps reinforce support of the spine, thereby reducing low back pain.
The Role of Back Muscles In Causing Back Pain
Stress can cause the back muscles to tighten, causing spasm and pain.
When the facet joints or certain other structures in the spine become injured or inflamed, the large back muscles can spasm and cause low back pain and marked limitation in motion.
Watch Video: What Is Your Back Muscle Spasm Telling You?
An episode of lower back pain that lasts for more than two weeks can lead to muscle weakness (since using the muscles hurts, the tendency is to avoid using them). This process leads to muscle wasting and subsequent weakening, which in turn causes more back pain because the muscles of the back are less able to help hold up the spine.
See Lumbar Spine Anatomy and Pain
Chronic stress can also lead to muscle weakness and back pain. Stress causes back muscles to tighten in a fight or flight response, depriving muscles of energy needed to support the spine.
Another key structure in low back pain is the hamstring muscles, the large muscles in the back of the thighs. Patients with tight hamstrings tend to develop low back pain, and those with lower back pain tend to develop tight hamstrings.
Muscle strength and flexibility are essential to maintaining the neutral spine position. Weak abdominal muscles cause hip flexor muscles to tighten causing an increase in the curve of the low back.
See Posture to Straighten Your Back
An unhealthy posture results when the curve is overextended called lordosis or swayback. Proper posture corrects muscle imbalances that can lead to low back pain by evenly distributing weight throughout the spine.
