What is a Herniated Disc?
Intervertebral discs sit between each vertebra of the spinal column and act as shock absorbers. They have a soft, jellylike inner layer and a tougher outer layer. A herniated disc – also known as a bulging disc – occurs when a part of the inner layer punches through the outer layer. This bulge may then press against the spinal cord or compress nerve roots, causing pain and other symptoms.
Causes and Risk Factors
The most common cause of herniated discs is age-related degeneration. As people age, the intervertebral discs have a tendency to dry out and weaken. This is known as degenerative disc disease.
When the outer layer of a disc becomes weak, the inner layer is more likely to bulge through. Though rare, trauma to the back or spine can also cause herniated discs.
Risk factors for herniated discs can include:
- Age: Disc degeneration accelerates as people age, making herniated discs more likely
- Gender: Men are more likely than women to develop herniated or bulging discs
- Genetics: Some research suggests there may be a genetic component to herniated disc risk
- Improper lifting technique: Lifting with the back instead of the legs can cause trauma to the discs, resulting in herniation
- Smoking: Smoking speeds up the process of discs drying out, which can weaken them and make them more susceptible to bulging
- Weight: Obesity increases strain on the intervertebral discs and increases the risk of herniation
Although herniated discs can happen in any region of the spine, most occur in the lower back, or lumbar spine. Symptoms include:
- Pain in the limbs: Herniated discs that press on a nerve root cause pain to whatever body part that nerve serves. If the herniation is in the lower back, the pain is most often felt in the buttocks and legs. If it is in the neck, usually one of the arms will hurt.
- Numbness, tingling or weakness in the muscles served by the nerve
- Loss of bladder or bowel control: This is a more rare symptom but it signifies a medical emergency. Urinary or bowel incontinence is caused by long-term compression of a nerve, sometimes referred to as cauda equina syndrome.
Herniated disc diagnosis usually starts with a physical examination and medical history. Often, that is all that is necessary to accurately diagnose a herniated disc. Doctors will want to know about symptoms, and during a physical exam they may check muscle strength, reflexes and sensation.
If a medical history and physical exam prove inconclusive, imaging is usually the next step. Herniated discs will not show up on X-rays, but X-rays are nevertheless useful in ruling out other possible sources of pain such as compression fractures or spinal tumors. Magnetic resonance imaging (MRI) and computed tomography (CT) scans can depict herniated discs.
A conservative nonsurgical approach is generally attempted before surgery. Conservative treatment can include:
- Anti-inflammatory drugs
- Corticosteroid injections
- Physical therapy to strengthen the surrounding muscles
- Anticonvulsants that may help with nerve pain
If a conservative approach fails to relieve symptoms, surgery may be warranted. The most common form of herniated disc surgery is a discectomy, in which the protruding piece of disc is surgically removed. A form of this surgery that is becoming popular is a microdiscectomy, in which surgeons use a microscope to see the area. This eliminates the need for a larger incision.
One of the most exciting forms of herniated disc surgery is laser disc decompression. This minimally invasive technique has been shown to be helpful in reducing or eliminating symptoms of herniated discs. One theory of why laser disc decompression works is that the laser energy heats the fluid inside the disc, reducing pressure and volume and causing the bulging part of the disc to retract.
At Edison Spine Center, our surgeons have decades of combined experience using minimally invasive techniques to treat herniated discs. If you are experiencing back pain, neck pain or pain radiating to the arms or legs, request an appointment for a consultation.