What is a herniated disc?
A herniated disc refers to an issue with one of the rubbery cushions (discs)that sit between your bones (vertebrae)that stack to form your spine. A spinal disc is composed of a soft, jelly-like center (nucleus), and a harder, more rubbery outer (annulus). A herniated disc is also known as a slipped disc. The lower back is the most common place to find a herniated disc. It can cause pain, numbness or weakness in one arm or leg depending on the location of the herniated disc. A herniated disc can cause no symptoms in many people. Those who have symptoms will usually experience improvement over time. The problem is rarely treated with surgery.
Signs and Symptoms of a Herniated Disc
The size and position of the herniated disc will determine the symptoms and signs that the patient may experience. The patient might feel a low backache, or not at all, if the herniated disc is not pressing on any nerves. It may cause pain, numbness or weakness in the region of the body where the nerve travels if it presses on a nerve. A herniated disc is usually preceded by low back pain, or a history of low back pain.
- Lumbar spine (lower back): Sciatica/Radiculopathy frequently results from a herniated disc in the lower back. The sciatic nerve is susceptible to pressure, which can lead to burning, tingling and pain radiating from the buttocks into the legs and feet. It is usually one side that is affected (left or right).
It is often described as electric shock-like and sharp. This pain may be worse if you are standing, walking, or seated. The pain can be worsened by straightening the leg on one side. Low back pain can also be experienced along with leg pain. However, acute sciatica often causes the pain in one’s leg to be worse than that in the low back.
- Cervical spine (neck): Cervical Radiculopathy can be described as a condition that causes nerve compression in the neck. It may present with dull or sharp pain between the shoulder blades or in the neck. Also, it may radiate down the arm to the fingers, or numbness in the arm or shoulder. Certain positions or movements may cause the pain to worsen.
Risk factors
The following factors can increase the likelihood of a herniated disc:
- Weight. Extra weight can cause extra strain on the discs at the lower back.
- Occupation. Back problems are more common in those who work in physically demanding occupations. A herniated disc can also be caused by repetitive lifting, pulling, pushing and twisting.
- Genetics. Some people inherit the predisposition to develop a herniated disc.
- Smoking. Smoking is thought to reduce the oxygen supply to discs and cause them to fail more quickly.
- Frequent driving. The vibrations from the motor vehicle engine and prolonged sitting can cause pressure to the spine.
- Being sedentary. Regular exercise can prevent a herniated disc.
How and when to seek medical care
Most herniated discs don’t require surgery. With time, the symptoms of sciatica/radiculopathy improve in approximately 9 out of 10 people. It can take anywhere from a few days up to several weeks for symptoms to improve.
General Guidelines
- Limit activity for two to three days. Walking is allowed if it is tolerated. If necessary, an anti-inflammatory such as ibuprofen may be used if the patient’s condition calls for it. It is not advised to use a bedrest.
- This is a time when primary care evaluation may be done.
- The American College of Radiology does not recommend radiographic imaging such as an MRI unless there have been symptoms for at least six weeks.
- If symptoms last more than four weeks, a referral to a spine specialist such as a neurosurgeon is recommended. Advanced imaging such as an MRI will be required by a specialist before the appointment.
If you have symptoms such as severe leg/arm weakness, loss of feeling in the genital/rectal area, no control over urine or stool, history of metastatic cancer, recent infection, fever or radiculopathy, or a fall/injury, an urgent evaluation is recommended. If progressive neurologic deficits (such as progressive weakness), are found on the exam, imaging should be performed sooner.
Diagnosis & Testing
Below are the testing modalities. MRI is the most commonly used imaging method for this condition. To complete the assessment of the vertebrae, plain x-rays are often taken of the affected area. A disc herniation can’t be seen on plain radiographs. Myelograms and CT scans were used more frequently before MRI. However, they are now less commonly ordered for diagnostic imaging. A very rare use of an electromyogram is to diagnose.
- X-ray: This is the use of radiation to create a film or a picture of a portion of the body. It can show the structure and outline of the vertebrae. To search for potential pain causes, X-rays are taken of the spine. tumors, infections, fractures, etc.
- Computed Tomography (CT or CAT scan: This is a diagnostic image that is created when X-rays are read by a computer. It can show the size and shape of the spinal canal and its contents as well as the structures surrounding it.
- Magnetic resonance imaging (MRI), a diagnostic test that creates 3D images of the body using powerful magnets, computer technology, can show the spine, nerve roots and surrounding areas, as well as enlargements, degeneration and tumors.
- Myelogram: A X-ray taken of the spinal canal after injection of contrast material in the cerebrospinal fluid space. It can show pressure on the spine or nerves due herniated discs or bone spurs or tumors.
- Electromyogram and Nerve Conduction Studies, (EMG/NCS), are tests that measure electrical impulses along nerve roots, peripheral nervous systems, and muscle tissue. This test will show if there is any ongoing nerve damage, whether the nerves are healing from an injury in the past, or if there is another area of nerve compression. This test is not often ordered.
Prevention
These steps will help to prevent a herniated disc:
- Exercise. Stabilizing and supporting the spine by strengthening the trunk muscles is a great way to strengthen them.
- Good posture is important. This will reduce pressure on your spine, and discs. When sitting for long periods, keep your back straight and aligned. Properly lift heavy objects, allowing your legs to do the bulk of the lifting.
- Keep your weight under control. An excess weight can put more pressure on the spine, discs, and make them more vulnerable to herniation.
- Stop smoking. Do not smoke.