The spinal column is made up of small bones called vertebrae stacked on top of each other. Nerves exit the spine between each of these bones -- one nerve on each side. These spinal nerves can be compressed, or pinched, by surrounding structures, such as a herniated disc. Pinched nerves often occur in the lower back, affecting the lowermost lumbar nerve -- L5 -- and the uppermost sacral nerve -- S1. Pinched L5-S1 spinal nerves can produce pain, numbness, tingling or weakness in your legs. See your doctor if you experience any of these symptoms.
Pain is a common symptom associated with L5-S1 pinched nerves. This may feel like a dull ache or a sharp or burning pain. It may start in your lower back, but then travels into your leg. L5 nerve compression causes pain along the outer border of the back of your thigh, while S1 nerve compression causes pain in your calf and the bottom of your foot. This pain can range from mild to severe and may be constant or intermittent. Pain often worsens with standing or sitting, or while sleeping. Sneezing, coughing or laughing may also increase your pain.
Numbness and Tingling
Leg numbness or tingling -- a pins and needles sensation -- often occurs with L5-S1 pinched nerves. These symptoms are generally felt between your big toe and second toe and on the top of your foot with L5 nerve compression. When an S1 nerve is pinched, these symptoms will be noticed along the outer edge and bottom of your foot. Numbness can make it difficult to feel pain on the bottom of your foot, which increases your risk of injury.
With prolonged L5-S1 nerve compression, you may develop weakness in the leg as nerve impulses to the muscles are interrupted. This can significantly impact your balance and walking ability. L5 nerve compression makes it difficult for you to lift up your big toe and pull your foot upward, while S1 nerve compression may make it difficult to point your foot down and rotate it outward. Surgery may be required to relieve L5-S1 nerve root compression if weakness has developed.
Reviewed by: Mary D. Daley, M.D.