A lumbar sprain is a stretching or tearing of the ligaments that connect the vertebrae of the back together. Most often, it is caused by an accident, a fall or awkward movement. The muscles of the lumbar region can also be affected.
Symptoms of a low back sprain include pain or numbness in the back, in one leg or both. These symptoms may vary throughout the day and increase when sitting, bending over, or performing any other movement that strains the back muscles.