Herniated intervertabral disk (HID)
HERNIATED INTERVERTEBRAL DISK
HERNIATED INTERVERTEBRAL DISK DEFINITION
A herniated disk refers to a problem with one of the rubbery cushions (disks) between the individual bones (vertebrae) that stack up to make your spine.
A spinal disk is a little like a jelly donut, with a softer center encased within a tougher exterior. Sometimes called a slipped disk or a ruptured disk, a herniated disk occurs when some of the softer “jelly” pushes out through a crack in the tougher exterior.
A herniated disk can irritate nearby nerves and result in pain, numbness or weakness in an arm or leg. On the other hand, many people experience no symptoms from a herniated disk. Most people who have a herniated disk don’t need surgery to correct the problem.
HERNIATED INTERVERTEBRAL DISK CAUSES
Disc herniations can result from general wear and tear, such as when performing jobs that require constant sitting. However, herniations often result from jobs that require lifting. Traumatic injury to lumbar discs commonly occurs when lifting while bent at the waist, rather than lifting with the legs while the back is straight. Minor back pain and chronic back tiredness are indicators of general wear and tear that make one susceptible to herniation on the occurrence of a traumatic event, such as bending to pick up a pencil or falling.
When the spine is straight, such as in standing or lying down, internal pressure is equalized on all parts of the discs. The spinal vertebrae are separated by disks filled with a soft, gelatinous substance. These disks cushion the spinal column and space between the vertebrae. These disks may herniate or rupture from trauma or strain. When this happens, the spinal nerves may become compressed, resulting in pain, numbness, or weakness.
The lower back, or lumbar area of the spine is the most common area for a slipped disk. The cervical disks are affected 8% of the time. The upper-to-mid-back disks are rarely involved.
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.
HERNIATED INTERVERTEBRAL DISK PATHOPHYSIOLOGY
It has been widely held that symptoms of lumbar disc disease are the result of either herniation of the nucleus pulposus through a mechanically weak anulus fibrosis or from tearing of the anulus itself. This can lead to radiculopathy from nerve root compression or an inflammatory process affecting nerve roots or the spinal cord. Herniation is thought to be the result of a defect in the anulus fibrosis, most likely the result of excessive stress applied to the disc.=15 Histological evaluation has revealed that whatever the cause of the tear, the extruded portion always involves material from the nucleus pulposus. Herniation most often occurs on the posterior or posterolateral aspect of the disc. Morphological characteristics, namely the arrangement of the anularfiber bundles, seem to contribute to the propensity for disc herniation on the posterior aspect of the disc. This directs the herniation toward the exiting and traversing nerve roots.
The degree of disease in the lumbar spine is characterized by the location of the abnormal portion of the disc. A disc bulge is a symmetrical extension of the disc beyond the endplates, whereas a protrusion is a focal area of extension still attached to the disc. An extruded fragment is one that is no longer connected to the disc, and a sequestered fragment is contained within the PLL.
HERNIATED INTERVERTEBRAL DISK SYMPTOMS
You can have a herniated disk without knowing it — herniated disks sometimes show up on spinal images of people who have no symptoms of a disk problem. But some herniated disks can be painful. Most herniated disks occur in your lower back (lumbar spine), although they can also occur in your neck (cervical spine).
The most common signs and symptoms of a herniated disk are:
- Arm or leg pain. If your herniated disk is in your lower back, you’ll typically feel the most intense pain in your buttocks, thigh and calf. It may also involve part of the foot. If your herniated disk is in your neck, the pain will typically be most intense in the shoulder and arm. This pain may shoot into your arm or leg when you cough, sneeze or move your spine into certain positions.
- Numbness or tingling. People who have a herniated disk often experience numbness or tingling in the body part served by the affected nerves.
- Weakness. Muscles served by the affected nerves tend to weaken. This may cause you to stumble, or impair your ability to lift or hold items.
HERNIATED INTERVERTEBRAL DISK DIAGNOSIS
A physical examination and history of pain may be all that a 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 a person sits down on an exam table and lifts the leg straight up usually suggests a herniated lumbar disk.
A foraminal compression test of Spurling is done to diagnose cervical radiculopathy. For this test, one will bend the head forward and to the sides while the doctor puts slight downward pressure on the top of the head. Increased pain or numbness during this test is usually a sign of cervical radiculopathy. Radiculopathy refers to any disease that affects the spinal nerve roots. A herniated disk is one cause of radiculopathy, or sciatica.
An MRI is commonly used to aid in making the diagnosis of a herniated disc. It is very important that patients understand that the MRI is only useful when used in conjunction with examination findings. It is normal for a MRI of the lumbar spine to have abnormalities, especially as people age. Patients in their 20s may begin to have signs of disc wear, and this type of wear would be expected on MRIs of patients in their 40s and 50s. This is the reason that your physician may not be concerned with some MRI findings noted by the radiologist.
EMG may be done to determine the exact nerve root that is involved and a nerve conduction velocity test may also be done, and a Myelogram may be done to determine the size and location of disk herniation.
HERNIATED INTERVERTEBRAL DISK TREATMENT
Conservative treatment — mainly avoiding painful positions and following a planned exercise and pain-medication regimen — relieves symptoms in 9 out of 10 people with a herniated disk.
- Over-the-counter pain medications. If your pain is mild to moderate, your doctor may tell you to take an over-the-counter pain medication, such as ibuprofen (Advil, Motrin IB, others) or naproxen (Aleve, others).
- Narcotics. If your pain doesn’t improve with over-the-counter medications, your doctor may prescribe narcotics, such as codeine or an oxycodone-acetaminophen combination (Percocet, Oxycontin, others), for a short time. Sedation, nausea, confusion and constipation are possible side effects from these drugs.
- Nerve pain medications. Drugs such as gabapentin (Neurontin, Gralise, Horizant), pregabalin (Lyrica), duloxetine (Cymbalta), tramadol (Ultram) and amitriptyline often help relieve nerve-damage pain. Because these drugs have a milder set of side effects than do narcotic medications, they’re increasingly being used as first line prescription medications for people who have herniated disks.
- Muscle relaxers. Muscle relaxants may be prescribed if you have muscle spasms. Sedation and dizziness are common side effects of these medications.
- Cortisone injections. Inflammation-suppressing corticosteroids may be given by injection directly into the area around the spinal nerves. Spinal imaging can help guide the needle more safely. Occasionally a course of oral steroids may be tried to reduce swelling and inflammation.
Physical therapists can show you positions and exercises designed to minimize the pain of a herniated disk. A physical therapist may also recommend:
- Heat or ice
- Electrical stimulation
- Short-term bracing for the neck or lower back
A very small number of people with herniated disks eventually need surgery. Your doctor may suggest surgery if conservative treatments fail to improve your symptoms after six weeks, especially if you continue to experience:
- Numbness or weakness
- Difficulty standing or walking
- Loss of bladder or bowel control
In many cases, surgeons can remove just the protruding portion of the disk. Rarely, however, the entire disk must be removed. In these cases, the vertebrae may need to be fused together with metal hardware to provide spinal stability. Rarely, your surgeon may suggest the implantation of an artificial disk.