Disc Herniation
Herniated Disc a.k.a. "Slipped Disc"
Herniation describes an abnormality of the intervertebral disc that is also known as a "slipped," "ruptured," or "torn" disc. This process occurs when the inner core of the intervertebral disc, (nucleus pulposus), bulges out through the outer ligamentous layer, (annulus fibrosis). This tear in the annulus fibrosis causes pain in the back at the point of herniation. If the protruding disc presses or irritates a spinal nerve, the pain may spread to the area of the body that is served by that nerve. Between each vertebra in the spine are pairs of spinal nerves,which branch off from the spinal cord to specific areas in the body. Any part of the skin that can experience hot and cold, pain or touch refers that sensation to the brain through one of these nerves. In turn, pressure on a spinal nerve from a herniated disc will cause pain in the part of the body that is served by that nerve.
Four Types of Disc Herniation:
Nuclear Herniation Disc Protrusion Nuclear Extrusion Sequestered Nucleus
Most disc ruptures occur when a person is in their thirties or forties when the nucleus pulposus is still a gelatinous substance, and most disc herniations will occur in the morning. The causes of this phenomenon are not entirely known, but are probably due to the physiology of the spine and the changes in the water content of the disc that occur throughout the day. The two most common locations for a herniated disc in the lower back are at the disc between fourth and fifth lumbar vertebra (L4/L5) and the disc between the fifth lumbar vertebra and the first sacral vertebra (L5/S1). These two discs account for over 95 percent of all painful disc herniations. A disc herniation can occur elsewhere along the spine, but lower lumbar herniations are the most common.
Symptoms of Disc Herniation
Frequently the patient's main complaint is a sharp, stabbing pain. In some cases there may be previous episodes of localized low back pain, which is present in the back and continues down the leg. This is known as sciatica when the goes below the knee. This pain is usually described as a deep and sharp, and may get worse as it moves down the affected leg. The onset of pain with a herniated disc may occur out of the blue or it may be announced by a tearing or snapping sensation in the spine that is thought to be the result of a sudden tear of part of the annulus fibrosis.
Diagnosis of Disc Problems
Patients with herniated discs usually complain of low back pain that may or may not radiate into the lower thigh or leg. They will often demonstrate a limitation in range of motion when asked to bend forward or lean backwards, and they may lean to one side as they try to bend.
Neurological and Orthopaedic examination performed by a doctor provides the most objective evidence of nerve root compression and may include the straight leg test. Abnormalities in strength and sensation of particular parts of the body are considered positive results. There are no laboratory tests that can detect the presence or absence of a herniated disc, but they may be helpful in the diagnosis of inflammation which can cause nerve root pain and irritation. An MRI is the gold standard for diagnosis of a herniated disc, but a CT scan (CAT scan) may often be helpful because it provides better visualization of the bones of the spinal column, indicating where the source of pressure on the nerve root is located. An EMG, (electromyographic test) may help to determine which nerve root in particular is being compressed or is not working normally in the situation where several nerve roots may be involved.
Treatment of Herniated Disc
The treatment for a vast majority of patients with a herniated disc does not normally include surgery. Eighty percent of patients will respond to conservative therapy when followed. Treatment is most effective when a patient and their doctor have a good relationship and the patient understands the rationale behind the prescribed treatment. The primary element of conservative treatment is controlled physical activity. Usually treatment will begin with chiropractic adjustments, electric stimulation known as interferential current, and ice for inflammation and analgesic effect. A short period of bed rest followed by physical therapy and a gradual return to normal activities is appropriate. Sitting is bad for this condition because the sitting posture puts a large amount of stress and pressure on the lumbar spine, which may increase the pressure on the affected nerve root. The appropriate use of medication can be an important part of conservative treatment. This can include aspirin, anti-inflammatory drugs, analgesics and muscle relaxants or tranquilizers to aid in pain control. Surgical treatment is reserved for patients in whom conservative treatment options are not effective and a sufficient period of time has passed to indicate that the patient may need to have surgery for resolution. A neurosurgical consult is appropriate at that time.