Lumbar Disk Herniation
Sometimes called a slipped or ruptured disk, a herniated disk most often occurs in your lower back. It is one of the most common causes of low back pain, as well as leg pain (sciatica).
Between 60 and 80 percent of people will experience low back pain at some point in their lives. A high percentage of people will have low back pain caused by a herniated disk.
Although a herniated disk can sometimes be very painful, most people feel much better with just a few months of nonsurgical treatment.
Your spine is made up of 24 bones, called vertebrae, that are stacked on top of one another. These bones connect to create a canal that protects the spinal cord.
Five vertebrae make up the lower back. This area is called your lumbar spine.
Other parts of your spine include:
- Spinal cord and nerves: These “electrical cables” travel through the spinal canal carrying messages between your brain and muscles.
- Intervertebral disks: In between your vertebrae are flexible intervertebral disks. They act as shock absorbers when your walk or run.
Intervertebral disks are flat and round, and about a half inch thick. They are made up of two components:
- Annulus fibrosus: This is the tough, flexible outer ring of the disk.
- Nucleus pulposus: This is the soft, jelly-like center of the disk.
A disk begins to herniate when its jelly-like nucleus pushes against its outer ring due to wear and tear or a sudden injury. This pressure against the outer ring causes lower back pain.
If the disk is very worn or injured, the jelly-like center may squeeze all the way through.
Once the nucleus breaks or herniates through the outer ring, pain in the lower back improves. Sciatic leg pain, however, increases. This is because the jelly-like material inflames the spinal nerves. It may also put pressure on these sensitive spinal nerves, causing pain, numbness, or weakness in one or both legs.
In many cases, a herniated disk is related to the natural aging of your spine.
In children and young adults, disks have a high water content. As we get older, our disks begin to dry out and weaken. The disks begin to shrink and the spaces between the vertebrae get narrower. This normal aging process is called disk degeneration.In addition to the gradual wear and tear that comes with aging, other factors can increase the likelihood of a herniated disk. Knowing what puts you at risk for a herniated disk can help you prevent further problems.
- Gender: Men between the ages of 30 and 50 are most likely to have a herniated disk.
- Improper lifting: Using your back muscles to lift heavy objects, instead of your legs, can cause a herniated disk. Twisting while you lift can also make your back vulnerable. Lifting with your legs, not your back, can protect your spine.
- Weight: Being overweight puts added stress on the disks in your lower back.
- Repetitive activities that strain your spine: Many jobs are physically demanding. Some require constant lifting, pulling, bending, or twisting. Using safe lifting and movement techniques can help protect your back.
- Frequent driving: Staying seated for long periods, plus the vibration from the car engine, can put pressure on your spine and disks.
- Sedentary lifestyle: Regular exercise is important in preventing many medical conditions, including a herniated disk.
- Smoking: It is believed that smoking lessens oxygen supply to the disk and causes more rapid degeneration.
For most people with a herniated disk, low back pain is the initial symptom. This pain may last for a few days, then improve. It is often followed by the eventual onset of leg pain, numbness, or weakness. This leg pain typically involves the leg below the knee, and foot and ankle. It is described as moving from the back or buttock down the leg into the foot.
Symptoms may be one or all of the following:
- Back pain
- Leg and/or foot pain (sciatica)
- Numbness in the leg and/or foot
- Weakness in the leg and /or foot
- Loss of bladder or bowel control (extremely rare) This may indicate a more serious problem called cauda equina syndrome. This condition is caused by the spinal nerve roots being compressed. It requires immediate medical attention.
Tests and Diagnosis
To determine whether you have a herniated lumbar disk, your doctor will ask you for a complete medical history and conduct a physical examination. The diagnosis can be confirmed by a magnetic resonance imaging (MRI) scan.
Medical History and Physical Examination
After discussing your symptoms and medical history, your doctor will examine your spine. During the physical examination, your doctor may conduct the following tests to help determine the cause of your low back pain.
- Neurological examination: A physical examination should include a neurological examination to detect weakness or sensory loss. To test muscle weakness, your doctor will assess how you walk on your heels and toes. Your thigh strength may also be tested. Your doctor can detect any loss of sensation by checking whether you are numb to light touch in the leg and foot.
- Straight leg raise (SLR) test: This test is a very accurate predictor of a disk herniation in patients under the age of 35. In this test, you lie on your back and your doctor lifts your affected leg. Your knee stays straight. If you feel pain down your leg and below the knee, you test positive for a herniated disk.
To help confirm a diagnosis of herniated disk, your doctor may recommend a magnetic resonance imaging (MRI) scan. This scan can create clear images of soft tissues like intervertebral disks.
In the majority of cases, a herniated lumbar disk will slowly improve within 6 to 8 weeks. By 3 to 4 months, most patients are free of symptoms.
Unless there are neurological deficits muscle weakness, difficulty walking or cauda equina syndrome, conservative care is the first course of treatment. It is not clear, however, that nonsurgical care is any better than letting the condition resolve on its own.
Common nonsurgical measures include:
- Rest: Usually 1-2 days of bed rest will calm severe back pain. Do not stay off your feet for longer, though. Take rest breaks throughout the day, but avoid sitting for long periods of time. Make all your movements slow and controlled. Change your daily activities so that you avoid movements that can cause further pain, especially bending forward and lifting.
- Anti-inflammatory medications: Medicines like ibuprofen or naproxen may relieve pain.
- Physical therapy: Specific exercises can strengthen your lower back and abdominal muscles.
- Epidural steroid injection: In this procedure, steroids are injected into your back to reduce local inflammation.
Of the above measures, only epidural injections have been proven effective at reducing symptoms. There is good evidence that epidural injections can be successful in 42-56% of patients who have not been helped by 6 weeks or more of other nonsurgical care.
Overall, the most effective nonsurgical care for lumbar herniated disk includes observation and an epidural steroid injection for short-term pain relief.
A small percentage of patients with lumbar disk herniations require surgery. This includes the urgent surgeries for people with neurological deficits or cauda equina syndrome.
Surgery for lumbar herniated disk is controversial. Research shows that patients 2 years post-surgery have the same results as patients treated nonsurgically. Patients with significant sciatica who have surgery, however, have better and more rapid pain relief. Surgery resolves symptoms faster for those with motor weakness or numbness, as well.
- Procedure: The most common surgical procedure for a herniated disk in the lower back is a lumbar microdiskectomy. Microdisketomy involves removing the herniated part of the disk and any fragments that are putting pressure on the spinal nerve.
- Rehabilitation: Most patients do not require formal physical therapy after surgery. A simple walking program 30 minutes each day, along with flexibility exercises for the back and legs, can be done as a home program.
Regardless of the kind of treatment prescribed, there is a 5% chance of the disk herniating again.
The risk of nonsurgical treatment is that your symptoms may take a long time to resolve. If after 6 months or so you elect to have surgery, the final outcome may not be as good as if you had elected surgery earlier.
The risk of surgical complications is exceptionally low. Possible complications include:
- Nerve damage
- Dural leak – An opening of the thin lining of the nerve root canal may cause loss of the watery liquid (cerebrospinal fluid) that bathes the nerves roots. When seen during surgery, the lining may be repaired. Sometimes headaches occur afterward, but typically improve with time.
- Hematoma causing nerve compression – This is caused by blood collecting around the nerve roots after the surgery.
Patients who opt for nonsurgical care can return to their normal activities as soon as their pain is manageable.
About 95% of the patients who have surgery experience dramatic pain relief immediately after surgery. Most patients can return to their normal daily activities within 1 to 2 weeks after surgery.
Last reviewed and updated: February 2009
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