What is lumbar disc herniation?
Lumbar disc herniation is a painful rupture of the outer cartilage of a lumbar disc and leakage of the inner cartilage. Lumbar discs are the cushions between the vertebrae in the lower back. If they become damaged by degeneration or injury, they may bulge abnormally or break open. If this ruptured disc puts pressure on the adjacent nerves, it can cause back and leg pain. Common terms for this condition include herniated disc, slipped disc or ruptured disc. Lumbar disc herniation is one of the most common causes of low back and leg pain.
How does lumbar disc herniation occur?
Lumbar disc herniation is usually caused by wear and tear or injury. As we age, our discs gradually lose the fluid that helps them maintain flexibility. Discs become stiffer and shorter, causing the vertebrae to move closer together. This is called degenerative disc disease. If a degenerated disc leaks outside the disc space, this causes a disc herniation that can press on a nerve. A herniated disc also may result from injuries to the spine, which can cause tiny tears or cracks in the disc's outer layer. The jellylike material inside is forced out, which causes the disc to bulge, break open or break into fragments.
What are the symptoms?
Symptoms of lumbar disc herniation may include:
- Leg pain (also called sciatica or radiculopathy)
- Lower back pain
- Numbness and tingling in the leg
- Weakness in the leg or foot
In some patients, a lumbar disc herniation can compress the entire caudaequina, the long nerve roots just below the waist, and cause neurologic dysfunction. This is a less common occurrence, but requires urgent medical attention. Symptoms include:
- Worsening pain, numbness and weakness in the lower back and legs that impairs normal activity
- Bladder or bowel dysfunction (such as loss of control or urination or bowel movements)
- Saddle anesthesia- a lack of sensation in the inner thighs, back of the legs, and rectal area
How is lumbar disc herniation diagnosed?
In addition to a complete physical exam and patient history, your doctor can use specific tests, including X-ray, MRI and CT scan, to diagnose a herniated disc. Sometimes, a test called an electromyogram is used to check electrical activity along the nerves and pinpoint the area of damage.
What is the treatment?
Many patients will improve with non-surgical treatment. This may include rest, non-steroidal anti-inflammatory medication, corticosteroids, epidural injections or physical therapy. If these conservative treatments do not work, if symptoms are worsening, or progressive weakness is occurring surgery may be necessary. The goal of surgery is to remove the portion of the disc that is pushing on the nerve root or spinal cord and relieve pressure off the nerve to improve pain a neurologic function.
The most common surgical procedure for a herniated disk in the lower back is a lumbar discectomy. The surgeon makes a small incision near the affected area and removes the herniated part of the disc that is putting pressure on the nerve. Any loose fragments of disc are also removed. The discectomy may include a laminectomy, the removal of a small piece of the vertebral bone called the lamina. This is done to open up the spinal canal so the spinal nerves have more room.