Foraminal stenosis between the L5 and S1 vertebrae refers to a narrowing in the area of the lower spine where nerve roots branch off the spinal cord and travel down the legs. More specifically, the L5 and S1 vertebrae mark the point where the last vertebra of the lumbar spine (L5) meets the top of the sacrum (S1), forming a junction known as the lumbosacral joint.
Not only are the L5 and S1 nerve roots the most commonly pinched nerves in the lower back, but these nerves also feed into the sciatic nerve – a long nerve that travels from the lower back, down each leg, and into the feet. When foraminal stenosis, or narrowing, is present in the L5 and S1 spinal segments, the sciatic nerve can become pinched or pressured, leading to sciatica, meaning pain that starts in the lower back and travels through the pelvic region, buttocks, and typically down one leg to the bottom of the feet.
In a normal spine, the bony vertebrae have bilateral foramen (or holes), which allow sets of spinal nerves to branch off the cord and pass through to the body. If one or more of the foramen becomes constricted, a spinal nerve root can become compressed, causing pain and interruption in the nerve’s signals. Lumbar foraminal stenosis (in the lower back) is particularly common and troublesome because it can pinch the sciatic nerve as it leaves the spinal column, leading to an intense burning, traveling pain through the buttocks, leg, calf, and toes, as well as tingling, numbness, and muscle weakness.
Foraminal stenosis at the L5 and S1 level can be caused by:
- Degenerative disc disease
- Herniated, bulging, or ruptured discs
- Arthritis of the spine
- The presence of a tumor, bone spur or other growth
A physician will typically try to initially treat chronic lower back or sciatica pain with a conservative treatment plan. In the event that a combination of physical therapy, pain medication, and the application of heat and ice are ineffective, surgical treatment becomes an option. The traditional approach to correcting foraminal stenosis has been open back surgery, but at Laser Spine Institute, our physicians offer a minimally invasive, outpatient alternative called a foraminotomy.
Through the advanced use of lasers and other micro-instruments, this procedure decompresses the nerves by carefully removing the bone and tissue causing the foraminal stenosis. Some patients feel instant relief from this procedure. Patients also enjoy a much quicker recovery and much less pain than with an open back procedure.
Contact Laser Spine Institute today for a complimentary review of your MRI or CT scan and to learn more about the endoscopic spine procedures currently available to help you find meaningful pain relief.