A herniated (slipped) disk occurs when all or part of a spinal disk is forced through a weakened part of the disk. This places pressure on nearby nerves.
See also: Low back pain
Lumbar radiculopathy; Cervical radiculopathy; Herniated intervertebral disk; Prolapsed intervertebral disk; Slipped disk; Ruptured disk; Herniated nucleus pulposus
Causes, incidence, and risk factors:
The bones (vertebrae) of the spinal column run down the back, connecting the skull to the pelvis. These bones protect nerves that come out of the brain and travel down your back, forming the spinal cord. Nerve roots are large nerves that branch out from the spinal cord and leave your spinal column between each vertebrae.
- The spinal vertebrae are separated by disks filled with a soft, gelatinous substance. These disks cushion the spinal column and space between your vertebrae.
- These disks may herniate (move out of place) or rupture from trauma or strain . When this happens, the spinal nerves may become compressed, resulting in pain, numbness, or weakness.
- The lower back (lumbar area) of the spine is the most common area for a slipped disk. The cervical (neck) disks are affected 8% of the time. The upper-to-mid-back (thoracic) disks are rarely involved.
Radiculopathy refers to any disease that affects the spinal nerve roots. A herniated disk is one cause of radiculopathy (sciatica ).
Disk herniation occurs more frequently in middle-aged and older men, especially those involved in strenuous physical activity. Other risk factors include any conditions present at birth (congenital) that affect the size of the lumbar spinal canal.
Low back or neck pain can vary widely. It may feel like a mild tingling, dull ache, or a burning or pulsating sensation. In some cases, the pain is severe enough that you are unable to move. You may also have numbness .
The pain most often occurs on one side of the body.
- With a lumbar (lower back) herniated disk, you may have sharp pain in one part of the leg, hip, or buttocks and numbness in other parts. You may also feel the sensations on the back of the calf or sole of the foot. The affected leg may feel weak.
- With a cervical (neck) disk herniation, you may have pain when moving your neck, deep pain near or over the shoulder blade, or pain that radiates to the upper arm, forearm, or (rarely) fingers.
The pain often starts slowly. It may get worse:
- After standing or sitting
- At night
- When sneezing, coughing, or laughing
- When bending backwards or walking more than a few yards, especially if it is caused by spinal stenosis
You may also have weakness in certain muscles. Sometimes, you may not notice it until your doctor examines you. In other cases, you will notice that you have a hard time lifting your leg or arm, standing on your toes on one side, squeezing tightly with one of your hands, or other problems.
The pain, numbness, or weakness often will go away or improve a lot over a period of weeks to months.
Signs and tests:
A physical examination and history of pain may be all that your health care provider needs to diagnose a herniated disk. A neurological examination will evaluate muscle reflexes, sensation, and muscle strength. Often, examination of the spine will reveal a decrease in the spinal curvature in the affected area.
Leg pain that occurs when you sit down on an exam table and lift your leg straight up usually suggests a herniated lumbar disk.
A foraminal compression test of Spurling is done to diagnose cervical radiculopathy. For this test, you will bend your head forward and to the sides while the health care provider puts slight downward pressure on the top of your head. Increased pain or numbness during this test is usually a sign of cervical radiculopathy.
- Spine x-ray may be done to rule out other causes of back or neck pain. However, it is not possible to diagnose a herniated disk by spinal x-ray alone.
- Spine MRI or spine CT will show spinal canal compression by the herniated disk.
- EMG may be done to determine the exact nerve root that is involved.
- Nerve conduction velocity test may also be done.
- Myelogram may be done to determine the size and location of disk herniation.
The first treatment for a herniated disk is a short period of rest with pain and anti-inflammatory medications, followed by physical therapy. Most people who follow these treatments will recover and return to their normal activities. A small number of people need to have further treatment, which may include steroid injections or surgery.
Nonsteroidal anti-inflammatory medications (NSAIDs) and narcotic painkillers will be given to people with a sudden herniated disk caused by some sort of injury (such as a car accident or lifting a very heavy object) that is immediately followed by severe pain in the back and leg.
If you have back spasms, you will usually receive muscle relaxants. On rare occasions, steroids may be given either by pill or directly into the blood through an IV.
NSAIDs are used for long-term pain control, but narcotics may be given if the pain does not respond to anti-inflammatory drugs.
Diet and exercise are crucial to improving back pain in overweight patients.
Physical therapy is important for nearly everyone with disk disease. Therapists will tell you how to properly lift, dress, walk, and perform other activities. They will work on strengthening the muscles that help support the spine. You will also learn flexibility of the spine and legs.
Steroid injections into the back in the area of the herniated disk may help control pain for several months. Such injections reduce swelling around the disk and relieve many symptoms. Spinal injections are usually done on an outpatient basis, using x-ray or fluoroscopy to identify the area where the injection is needed.
Surgery may be an option for the few patients whose symptoms do not go away despite other treatments and time.
See also: Diskectomy
Ask your doctor which treatment options are best for you.
Most people will improve with conservative treatment. A small percentage may continue to have chronic back pain even after treatment.
It may take several months to a year or more to resume all activities without pain or strain to the back. People with certain occupations that involve heavy lifting or back strain may need to change job activities to avoid recurrent back injury.
- Long-term back pain
- Loss of movement or sensation in the legs or feet
- Loss of bowel and bladder function
- Permanent spinal cord injury (very rare)
Calling your health care provider:
Call your health care provider if:
- You develop persistent, severe back pain develops
- You have any numbness, loss of movement, weakness, or bowel or bladder changes
Safe work and play practices, proper lifting techniques, and weight control may help prevent back injury in some people.
Some health care providers recommend the use of back braces to help support the spine. Such braces can help prevent injuries in people whose work requires them to lift heavy objects. However, overuse of these devices can weaken the abdominal and back muscles, making the problem worse.
Chou R, Huffman LH. Medications for acute and chronic low back pain: a review of the evidence for an American Pain Society/American College of Physicians clinical practice guideline. Ann Intern Med. 2007;147:505-514.
Chou R, Huffman LH. Nonpharmacologic therapies for acute and chronic low back pain: a review of the evidence for an American Pain Society/American College of Physicians clinical practice guideline. Ann Intern Med. 2007;147:492-504.
Chou R, Huffman LH. Diagnosis and treatment of low back pain: a review of the evidence for an American Pain Society/American College of Physicians clinical practice guideline. Ann Intern Med. 2007;147:478-491.