Lumbar strain: A stretching injury to the ligaments, tendons, and/or muscles of the low back. The stretching incident results in microscopic tears of varying degrees in these tissues. Lumbar strain is one of the most common causes of low back pain. The injury can occur because of overuse, improper use, or trauma. It is classified as "acute" if it has been present for days to weeks. If the strain lasts longer than 3 months, it is referred to as "chronic."
Lumbar strain most often occurs in persons in their forties, but can happen at any age. The condition is characterized by localized discomfort in the low back area with onset after an event that mechanically stressed the lumbar tissues. The diagnosis of lumbar strain is based on the history of injury, the location of the pain, and exclusion of nervous system injury. Usually, x-ray testing is only helpful to exclude bone abnormalities.
The treatment of lumbar strain consists of resting the back (to avoid re-injury), medications to relieve pain and muscle spasm, local heat applications, massage, and eventual (after the acute episode resolves) reconditioning exercises to strengthen the low back and abdominal muscles. Long periods of inactivity in bed are no longer promoted as this treatment may actually slow recovery. Spinal manipulation for periods of up to 1 month has been found helpful in some patients that do not have signs of nerve irritation. Future injury is avoided by using back protection techniques during activities and support devices as needed at home or work.