Herniated Disk
Herniated Disk
Definition
Disk herniation is a rupture of fibrocartilagenous material (annulus fibrosis) that surrounds the intervertebral disk. This rupture involves the release of the disk's center portion containing a gelatinous substance called the nucleus pulposus. Pressure from the vertebrae above and below may cause the nucleus pulposus to be forced outward, placing pressure on a spinal nerve and causing considerable pain and damage to the nerve. This condition most frequently occurs in the lumbar region and is also commonly called herniated nucleus pulposus, prolapsed disk, ruptured intervertebral disk, or slipped disk.
Description
The spinal column is made up of 26 vertebrae that are joined together and permit forward and backward bending, side bending, and rotation of the spine. Five distinct regions comprise the spinal column, including the cervical (neck) region, thoracic (chest) region, lumbar (low back) region, sacral, and coccygeal (tailbone) region. The cervical region consists of seven vertebrae, the thoracic region includes 12 vertebrae, and the lumbar region contains five vertebrae. The sacrum is composed of five fused vertebrae, which are connected to four fused vertebrae forming the coccyx. Intervertebral disks lie between each adjacent vertebra.
Each disk is composed of a gelatinous material in the center, called the nucleus pulposus, surrounded by rings of a fibrous tissue (annulus fibrosus). In disk herniation, an intervertebral disk's central portion herniates through the surrounding annulus fibrosus into the spinal canal, putting pressure on a nerve root. (There is often a progression of small fissures in the annulus fibrosis before the disk herniates.) Disk herniation most commonly affects the lumbar region between the fifth lumbar vertebra and the first sacral vertebra. However, disk herniation can also occur in the cervical spine. The incidence of cervical disk herniation is most common between the fifth and sixth cervical vertebrae. The second most common area for cervical disk herniation occurs between the sixth and seventh cervical vertebrae. Disk herniation is less common in the thoracic region.
Predisposing factors associated with disk herniation include age, gender, and work environment. The peak age for occurrence of disk herniation is between 20-45 years of age. Studies have shown that males are more commonly affected than females in lumbar disk herniation by a 3:2 ratio. Genetic factors are suspected of playing a role in disk herniation. Prolonged exposure to a bent-forward work posture is correlated with an increased incidence of disk herniation. Pain from a herniated disk is usually greatest when sitting and is lessened when standing.
There are four classifications of disk pathology:
- A protrusion may occur where a disk bulges without rupturing the annulus fibrosis.
- The disk may prolapse where the nucleus pulposus migrates to the outermost fibers of the annulus fibrosis.
- There may be a disk extrusion, which is the case if the annulus fibrosis perforates and material of the nucleus moves into the epidural space.
- The sequestrated disk may occur as fragments from the annulus fibrosis and nucleus pulposus are outside the disk proper.
Causes and symptoms
Any direct, forceful, and vertical pressure on the lumbar disks can cause the disk to push its fluid contents into the vertebral body. Herniated nucleus pulposus may occur suddenly from lifting, twisting, or direct injury, or it can occur gradually from degenerative changes with episodes of intensifying symptoms. As individuals age, the intervertebral disk changes in shape and volume. Changes in the chemical and mechanical characteristics of the disk also occur. It is these changes that predispose certain individuals to disk herniation. The annulus may also become weakened over time, allowing stretching or tearing and leading to a disk herniation. Depending on the location of the herniation, the herniated material can also press directly on nerve roots or on the spinal cord, causing a shock-like pain (sciatica ) down the legs, weakness, numbness, or problems with bowels, bladder, or sexual function.
Diagnosis
A variety of non-invasive physical tests can be performed to help diagnose disk herniation. A straight-leg raising test may be performed by the health practitioner. If severe pain is produced in the back of the leg, then it may suggest a lumbar nerve root problem. A crossed straight-leg raising test may also be performed. This involves raising the leg opposite to that with current pain. This test tends to produce a more localized but less intense pain than the straight-leg raising test. Several radiographic tests are useful for confirming a diagnosis of disk herniation and locating the source of pain. These tests also help the surgeon indicate the extent of the surgery needed to fully decompress the nerve. X rays show structural changes of the lumbar spine. Myelography is a special x ray of the spine in which a dye or air is injected into the patient's spinal canal. The patient lies strapped to a table as the table tilts in various directions and spot x rays are taken. X rays showing a narrowed dye column in the intervertebral disk area indicate possible disk herniation.
Computed tomography, or computed axial tomography (CT or CAT) scans, reveal the details of pathology necessary to obtain consistently good surgical results. Magnetic resonance imaging (MRI) analysis of the disks can accurately detect the early stages of disk aging and degeneration. MRI is most useful in assessing how the disk and nerve roots change over time. The MRI has become the standard diagnostic imaging tool for disk herniation. A newer technology called magnetic resonance myelography does not provide a better overall image of the spine than an MRI, but it can improve diagnosis of disk herniation in some cases.
Treatment
Drugs
Unless serious neurologic symptoms occur, herniated disks can initially be treated with pain medication and up to 48 hours of bed rest. There is no proven benefit from resting more than 48 hours. Many patients benefit from lying on a very firm mattress or an ordinary mattress with a board placed underneath. Heat or cold applied to the affected region often helps many patients. Patients are then encouraged to gradually increase their activity. Pain medications, including non-steroidal anti-inflammatory drugs, muscle relaxers, or in severe cases, narcotics, may be continued if needed.
Epidural steroid injections have been used to decrease pain by injecting an anti-inflammatory drug, usually a corticosteroid, around the nerve root to reduce inflammation and edema (swelling). This partly relieves the pressure on the nerve root as well as resolves the inflammation. Some physicians are using trigger point injections of lidocaine without epinephrine to provide localized pain relief for extended periods of time. Some of these physicians also use electrical or ultrasound therapy over these localized areas, but these methods have not been scientifically validated.
Physical therapy
Physical therapists are skilled in treating acute back pain caused by disk herniation. The physical therapist can provide noninvasive therapies, such as ultrasound or diathermy to project heat deep into the tissues of the back or administer manual therapy, if mobility of the spine is impaired. They may help improve posture and develop an exercise program for recovery and long-term protection. Appropriate exercise can help take pressure off inflamed nerve structures, while improving overall posture and flexibility. Traction can be used to try to decrease pressure on the disk. A lumbar support can be helpful for a herniated disk at this level as a temporary measure to reduce pain and improve posture.
Surgery
Surgery is often appropriate for conditions that do not improve with the usual treatment. In this event, a strong, flexible spine is important for a quick recovery after surgery. There are several surgical approaches to treating a herniated disk, including the classic discectomy, microdiscectomy, or percutaneous discectomy. The basic differences among these procedures are the size of the incision, how the disk is reached surgically, and how much of the disk is removed.
Discectomy is the surgical removal of the portion of the disk that is putting pressure on a nerve causing the back pain. In the classic disectomy, the surgeon first enters through the skin and then removes a bony portion of the vertebra called the lamina, hence the term laminectomy. The surgeon removes the disk material that is pressing on a nerve. Rarely is the entire lamina or disk removed. Often, only one side is removed, and the surgical procedure is termed hemilaminectomy.
In microdiscectomy, through the use of an operating microscope, the surgeon removes the offending bone or disk tissue until the nerve is free from compression or stretch. This procedure is possible using local anesthesia. Microsurgery techniques vary and have several advantages over the standard discectomy, such as a smaller incision, less trauma to the musculature and nerves, and easier identification of structures by viewing into the disk space through microscope magnification.
Percutaneous disk excision is performed on an outpatient basis, is less expensive than other surgical procedures, and does not require a general anesthesia. The purpose of percutaneous disk excision is to reduce the volume of the affected disk indirectly by partial removal of the nucleus pulposus, leaving all the structures important to stability practically unaffected. In this procedure, large incisions are avoided by inserting devices that have cutting and suction capability. Suction is applied and the disk is sliced and aspirated.
Arthroscopic microdiscectomy is similar to percutaneous discectomy, however it incorporates modified arthroscopic instruments, including scopes and suction devices. A suction irrigation of saline solution is established through two entry sites. A video discoscope is introduced from one site and the deflecting instruments from the opposite side. In this way, the surgeon is able to search and extract the nuclear fragments under direct visualization.
Laser disk decompression is performed using similar means as percutaneous excision and arthroscopic microdiscectomy, however laser energy is used to remove the disk tissue. Here, laser energy is percutaneously introduced through a needle to vaporize a small volume of nucleus pulposus, thereby dropping the pressure of the disk and decompressing the involved neural tissues. One disadvantage of this procedure is the high initial cost of the laser equipment. It is important to realize that only a very small percentage of people with herniated lumbar disks go on to require surgery. Further, surgery should be followed by appropriate rehabilitation to decrease the chance of reinjury.
Chemonucleolysis
Chemonucleolysis is an alternative to surgical excision. Chymopapain, a purified enzyme derived from the papaya plant, is injected percutaneously into the disk space to reduce the size of the herniated disks. It hydrolyses proteins, thereby decreasing waterbinding capacity, when injected into the nucleus pulposus inner disk material. The reduction in size of the disk relieves pressure on the nerve root.
Spinal fusion
Spinal fusion is the process by which bone grafts harvested from the iliac crest (thick border of the ilium located on the pelvis) are placed between the intervertebral bodies after the disk material is removed. This approach is used when there is a need to reestablish the normal bony relationship between the vertebrae. A total discectomy may be needed in some cases because lumbar spinal fusion can help prevent recurrent lumbar disk herniation at a particular level.
Alternative treatment
Acupuncture involves the injection of fine needles to relieve pain. An acupuncturist determines the location of the nerves affected by the herniated disk and positions the needles appropriately. Massage therapists may also provide short-term relief from a herniated disk. Following manual examination and x-ray diagnosis, chiropractic treatment usually includes manipulation to correct muscle and joint malfunctions, while care is taken not to place an additional strain on the injured disk. If a full trial of conservative therapy fails, or if neurologic problems (weakness, bowel or bladder problems, and sensory loss) develop, the next step is usually evaluation by an orthopedic surgeon.
Health care team roles
Nurses play an important role in the diagnosis and treatment of disk herniation disease. They assist health care practitioners in performing basic physical testing, such as the straight-leg raising test. They also play an important role in determining the history of the patient and how the patient developed the herniated disk. They also will often assist in procedures such as the steroid or lidocaine injection. Surgical nurses assist in the operative repair of herniated disks.
Physical therapists play an important role in the prevention and treatment of patients with herniated disk disease. They can create an exercise and posture program that can reduce the risk of developing the condition in the first place as well as generate a course of therapy that will help restore function in those with serious disease.
Radiologic technologists play a critical role in the diagnosis of disk herniation. They are involved in the three most important diagnostic imaging tests: CAT scans, MRI procedures, and x rays.
Patient education
Nurses play a critical role in patient education in the prevention and treatment of disk herniation. One of the most important areas in which they educate patients is following disk herniation surgery. These postoperative care instructions are vital to the success of the surgery. Pharmacists play a key role in dispensing accurate information about the proper use of drugs, particularly non-steroidal anti-inflammatory agents, muscle relaxants, and narcotic-based compounds. They also provide instructions to patients on the proper use of drugs prescribed following surgery. Physical therapists instruct individuals on how to properly lift heavy objects, how to maintain good posture while working and during other activities, and how to perform certain exercises to prevent or treat disk herniation. Occupational therapists provide information to individuals and employers on how to minimize back and neck strain in the workplace. Dietitians can design a weight-loss program in those cases where extra weight helped precipitate and aggravate disk herniation.
Prognosis
Only 5-10% of patients with unrelenting sciatica and neurological involvement, leading to chronic pain of the lumbar spine, need to have a surgical procedure performed. This strongly suggests that many patients with herniated disks at the lumbar level respond well to conservative treatment. For those patients who do require surgery for lumbar disk herniation, the reviewed procedures of nerve root decompression caused by disk herniation is favorable. Results of studies varied from 60-90% success rates. Disk surgery has progressively evolved in the direction of decreasing invasiveness. Each surgical procedure is not without possible complications, which can lead to chronic low back pain and restricted lifestyle.
Prevention
Proper exercises to strengthen the lower back and abdominal muscles are key in preventing excess stress and compressive forces on lumbar disks. Good posture will help prevent problems on cervical, thoracic, and lumbar disks. A good flexibility program is critical for prevention of muscle and spasm that can cause an increase in compressive forces on disks at any level. Proper lifting of heavy objects is important for all muscles and levels of the individual disks. Good posture in sitting, standing, and lying down is helpful for the spine. Losing weight, if needed, can prevent weakness and unnecessary stress on the disks caused by obesity. Choosing proper footwear may also be helpful to reduce the impact forces to the lumbar disks while walking on hard surfaces. Wearing special back support devices may be helpful if heavy lifting is required with combinations of twisting.
KEY TERMS
Annulus fibrosis— The outer portion of the intervertebral disk made primarily of fibrocartilage rings.
Epidural space— The space immediately surrounding the outermost membrane of the spinal cord.
Excision— The process of excising, removing, or amputating.
Fibrocartilage— Cartilage that consists of dense fibers.
Nucleus pulposus— The center portion of the intervertebral disk that is made up of a gelatinous substance.
Percutaneous— Performed through the skin.
Resources
BOOKS
Beers, Mark H. et al. The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck, 2005.
Current Medical Diagnosis & Treatment 2001. Ed. Lawrence M. Tierney et al. New York: Lange, 2001.
Fauci, Anthony S. Harrison's Principles of Internal Medicine. New York: McGraw-Hill, 1998.
Ferri, Fred F. Ferri's Clinical Advisor. St. Louis: Mosby, 2001.
PERIODICALS
Humphreys, S. Craig et al. "Clinical Evaluation and Treatment Options for Herniated Lumbar Disc." American Family Physician 59 (1999).
McCall, I. W. "Lumbar Herniated Disks." Radiologic Clinicians of North America 38 (200).
Miyamoto, H. et al. "The Role of Cyclooxygenase-2 and Inflammatory Cytokines in Pain Induction of Herniated Lumbar Intervertebral Disc." Kobe Journal of Medical Science 46 (2000).
Patel, Atul T. et al. "Diagnosis and Management of Acute Low Back Pain." American Family Physician 61 (2000).
Pui, M.H. et al. "Value of Magnetic Resonance Myelography in the Diagnosis of Disk Herniation and Spinal Stenosis." Australasia Radiology 44 (2000).
Vanichkachorn, J. S. et al. "Thoracic Disk Disease: Diagnosis and Treatment." Journal of the American Academy of Orthopedic Surgery 8 (2000).
OTHER
FreedomQuest Inc. "Acupuncture." 1998. 〈http://acupuncture.com/Acup/AcuInd.htm〉.
Medical Strategies Inc. (MSI). "Back Pain." 1993–1998. Healthtouch Online. 〈http://www.healthtouch.com〉.
ORGANIZATIONS
American Chronic Pain Association. P.O. Box 850, Rocklin, CA 95677-0850. (916) 632-0922. 〈http://www.theacpa.org〉.
National Chronic Pain Outreach Association. P.O. Box 274, Millboro, VA 24460. (540) 862-9437. [email protected].
Herniated Disk
Herniated disk
Definition
Disk herniation is a rupture of fibrocartilagenous material (annulus fibrosis) that surrounds the intervertebral disk. This rupture involves the release of the disk's center portion containing a gelatinous substance called the nucleus pulposus. Pressure from the vertebrae above and below may cause the nucleus pulposus to be forced outward, placing pressure on a spinal nerve and causing considerable pain and damage to the nerve. This condition most frequently occurs in the lumbar region and is also commonly called herniated nucleus pulposus, prolapsed disk, ruptured intervertebral disk, or slipped disk.
Description
The spinal column is made up of 26 vertebrae that are joined together and permit forward and backward bending, side bending, and rotation of the spine. Five distinct regions comprise the spinal column, including the cervical (neck) region, thoracic (chest) region, lumbar (low back) region, sacral and coccygeal (tailbone) region. The cervical region consists of seven vertebrae, the thoracic region includes 12 vertebrae, and the lumbar region contains five vertebrae. The sacrum is composed of five fused vertebrae, which are connected to four fused vertebrae forming the coccyx. Intervertebral disks lie between each adjacent vertebra.
Each disk is composed of a gelatinous material in the center, called the nucleus pulposus, surrounded by rings of a fibrous tissue (annulus fibrosus). In disk herniation, an intervertebral disk's central portion herniates through the surrounding annulus fibrosus into the spinal canal, putting pressure on a nerve root. (There is often a progression of small fissures in the annulus fibrosis before the disk herniates.) Disk herniation most commonly affects the lumbar region between the fifth lumbar vertebra and the first sacral vertebra. However, disk herniation can also occur in the cervical spine. The incidence of cervical disk herniation is most common between the fifth and sixth cervical vertebrae. The second most common area for cervical disk herniation occurs between the sixth and seventh cervical vertebrae. Disk herniation is less common in the thoracic region.
Predisposing factors associated with disk herniation include age, gender, and work environment. The peak age for occurrence of disk herniation is between 20–45 years of age. Studies have shown that males are more commonly affected than females in lumbar disk herniation by a 3:2 ratio. Genetic factors are suspected of playing a role in disk herniation. Prolonged exposure to a bent-forward work posture is correlated with an increased incidence of disk herniation. Pain from a herniated disk is usually greatest when sitting and is lessened when standing.
There are four classifications of disk pathology:
- A protrusion may occur where a disk bulges without rupturing the annulus fibrosis.
- The disk may prolapse where the nucleus pulposus migrates to the outermost fibers of the annulus fibrosis.
- There may be a disk extrusion, which is the case if the annulus fibrosis perforates and material of the nucleus moves into the epidural space.
- The sequestrated disk may occur as fragments from the annulus fibrosis and nucleus pulposus are outside the disk proper.
Causes and symptoms
Any direct, forceful, and vertical pressure on the lumbar disks can cause the disk to push its fluid contents into the vertebral body. Herniated nucleus pulposus may occur suddenly from lifting, twisting, or direct injury, or it can occur gradually from degenerative changes with episodes of intensifying symptoms. As individuals age, the intervertebral disk changes in shape and volume. Changes in the chemical and mechanical characteristics of the disk also occur. It is these changes that predispose certain individuals to disk herniation. The annulus may also become weakened over time, allowing stretching or tearing and leading to a disk herniation. Depending on the location of the herniation, the herniated material can also press directly on nerve roots or on the spinal cord , causing a shock-like pain (sciatica ) down the legs, weakness, numbness, or problems with bowels, bladder, or sexual function.
Diagnosis
A variety of non-invasive physical tests can be performed to help diagnose disk herniation. A straight-leg raising test may be performed by the health practitioner. If severe pain is produced in the back of the leg, then it may suggest a lumbar nerve root problem. A crossed straight-leg raising test may also be performed. This involves raising the leg opposite to that with current pain. This test tends to produce a more localized but less intense pain than the straight-leg raising test. Several radiographic tests are useful for confirming a diagnosis of disk herniation and locating the source of pain. These tests also help the surgeon indicate the extent of the surgery needed to fully decompress the nerve. X rays show structural changes of the lumbar spine. Myelography is a special x ray of the spine in which a dye or air is injected into the patient's spinal canal. The patient lies strapped to a table as the table tilts in various directions and spot x rays are taken. X rays showing a narrowed dye column in the intervertebral disk area indicate possible disk herniation.
Computed tomography, or computed axial tomography (CT or CAT) scans reveal the details of pathology necessary to obtain consistently good surgical results. Magnetic resonance imaging (MRI) analysis of the disks can accurately detect the early stages of disk aging and degeneration. MRI is most useful in assessing how the disk and nerve roots change over time. The MRI has become the standard diagnostic imaging tool for disk herniation. A newer technology called magnetic resonance myelography does not provide a better overall image of the spine than an MRI, but it can improve diagnosis of disk herniation in some cases.
Treatment
Drugs
Unless serious neurologic symptoms occur, herniated disks can initially be treated with pain medication and up to 48 hours of bed rest. There is no proven benefit from resting more than 48 hours. Many patients benefit from lying on a very firm mattress or an ordinary mattress with a board placed underneath. Heat or cold applied to the affected region often helps many patients. Patients are then encouraged to gradually increase their activity. Pain medications, including non-steroidal anti-inflammatory drugs, muscle relaxers, or in severe cases, narcotics, may be continued if needed.
Epidural steroid injections have been used to decrease pain by injecting an anti-inflammatory drug, usually a corticosteroid, around the nerve root to reduce inflammation and edema (swelling). This partly relieves the pressure on the nerve root as well as resolves the inflammation. Some physicians are using trigger point injections of lidocaine without epinephrine to provide localized pain relief for extended periods of time. Some of these physicians also use electrical or ultrasound therapy over these localized areas, but these methods have not been scientifically validated.
Physical therapy
Physical therapists are skilled in treating acute back pain caused by disk herniation. The physical therapist can provide noninvasive therapies, such as ultrasound or diathermy to project heat deep into the tissues of the back or administer manual therapy, if mobility of the spine is impaired. They may help improve posture and develop an exercise program for recovery and long-term protection. Appropriate exercise can help take pressure off inflamed nerve structures, while improving overall posture and flexibility. Traction can be used to try to decrease pressure on the disk. A lumbar support can be helpful for a herniated disk at this level as a temporary measure to reduce pain and improve posture.
Surgery
Surgery is often appropriate for conditions that do not improve with the usual treatment. In this event, a strong, flexible spine is important for a quick recovery after surgery. There are several surgical approaches to treating a herniated disk, including the classic discectomy, microdiscectomy, or percutaneous discectomy. The basic differences among these procedures are the size of the incision, how the disk is reached surgically, and how much of the disk is removed.
Discectomy is the surgical removal of the portion of the disk that is putting pressure on a nerve causing the back pain. In the classic disectomy, the surgeon first enters through the skin and then removes a bony portion of the vertebra called the lamina, hence the term laminectomy. The surgeon removes the disk material that is pressing on a nerve. Rarely is the entire lamina or disk removed. Often, only one side is removed and the surgical procedure is termed hemilaminectomy.
In microdiscectomy, through the use of an operating microscope , the surgeon removes the offending bone or disk tissue until the nerve is free from compression or stretch. This procedure is possible using local anesthesia . Microsurgery techniques vary and have several advantages over the standard discectomy, such as a smaller incision, less trauma to the musculature and nerves, and easier identification of structures by viewing into the disk space through microscope magnification.
Percutaneous disk excision is performed on an out-patient basis, is less expensive than other surgical procedures, and does not require a general anesthesia . The purpose of percutaneous disk excision is to reduce the volume of the affected disk indirectly by partial removal of the nucleus pulposus, leaving all the structures important to stability practically unaffected. In this procedure, large incisions are avoided by inserting devices that have cutting and suction capability. Suction is applied and the disk is sliced and aspirated.
Athroscopic microdiscectomy is similar to percutaneous discectomy, however it incorporates modified arthroscopic instruments, including scopes and suction devices. A suction irrigation of saline solution is established through two entry sites. A video discoscope is introduced from one site and the deflecting instruments from the opposite side. In this way, the surgeon is able to search and extract the nuclear fragments under direct visualization.
Laser disk decompression is performed using similar means as percutaneous excision and arthroscopic microdiscectomy, however laser energy is used to remove the disk tissue. Here, laser energy is percutaneously introduced through a needle to vaporize a small volume of nucleus pulposus, thereby dropping the pressure of the disk and decompressing the involved neural tissues. One disadvantage of this procedure is the high initial cost of the laser equipment. It is important to realize that only a very small percentage of people with herniated lumbar disks go on to require surgery. Further, surgery should be followed by appropriate rehabilitation to decrease the chance of reinjury.
Chemonucleolysis
Chemonucleolysis is an alternative to surgical excision. Chymopapain, a purified enzyme derived from the papaya plant, is injected percutaneously into the disk space to reduce the size of the herniated disks. It hydrolyses proteins , thereby decreasing water-binding capacity, when injected into the nucleus pulposus inner disk material. The reduction in size of the disk relieves pressure on the nerve root.
Spinal fusion
Spinal fusion is the process by which bone grafts harvested from the iliac crest (thick border of the ilium located on the pelvis) are placed between the intervertebral bodies after the disk material is removed. This approach is used when there is a need to reestablish the normal bony relationship between the vertebrae. A total discectomy may be needed in some cases because lumbar spinal fusion can help prevent recurrent lumbar disk herniation at a particular level.
Alternative treatment
Acupuncture involves the injection of fine needles to relieve pain. An acupuncturist determines the location of the nerves affected by the herniated disk and positions the needles appropriately. Massage therapists may also provide short-term relief from a herniated disk. Following manual examination and x-ray diagnosis, chiropractic treatment usually includes manipulation to correct muscle and joint malfunctions, while care is taken not to place an additional strain on the injured disk. If a full trial of conservative therapy fails, or if neurologic problems (weakness, bowel or bladder problems, and sensory loss) develop, the next step is usually evaluation by an orthopedic surgeon.
Health care team roles
Nurses play an important role in the diagnosis and treatment of disk herniation disease. They assist health care practitioners in performing basic physical testing, such as the straight-leg raising test. They also play an important role in determining the history of the patient and how the patient developed the herniated disk. They also will often assist in procedures such as the steroid or lidocaine injection. Surgical nurses assist in the operative repair of herniated disks.
Physical therapists play an important role in the prevention and treatment of patients with herniated disk disease. They can create an exercise and posture program that can reduce the risk of developing the condition in the
KEY TERMS
Annulus fibrosis —The outer portion of the inter-vertebral disk made primarily of fibrocartilage rings.
Epidural space —The space immediately surrounding the outer most membrane of the spinal cord.
Excision —The process of excising, removing, or amputating.
Fibrocartilage —Cartilage that consists of dense fibers.
Nucleus pulposus —The center portion of the intervertebral disk that is made up of a gelatinous substance.
Percutaneous —Performed through the skin.
first place as well as generate a course of therapy that will help restore function in those with serious disease.
Radiologic technologists play a critical role in the diagnosis of disk herniation. They are involved in the three most important diagnostic imaging tests: CAT scans, MRI procedures, and x rays.
Patient education
Nurses play a critical role in patient education in the prevention and treatment of disk herniation. One of the most important areas in which they educate patients is following disk herniation surgery. These postoperative care instructions are vital to the success of the surgery. Pharmacists play a key role in dispensing accurate information about the proper use of drugs, particularly non-steroidal anti-inflammatory agents, muscle relaxants , and narcotic-based compounds. They also provide instructions to patients on the proper use of drugs pre scribed following surgery. Physical therapists instruct individuals on how to properly lift heavy objects, how to maintain good posture while working and during other activities, and how to perform certain exercises to pre vent or treat disk herniation. Occupational therapists provide information to individuals and employers on how to minimize back and neck strain in the workplace. Dietitians can design a weight-loss program in those cases where extra weight helped precipitate and aggra vate disk herniation.
Prognosis
Only 5–10% of patients with unrelenting sciatica and neurological involvement, leading to chronic pain of the lumbar spine, need to have a surgical procedure performed. This strongly suggests that many patients with herniated disks at the lumbar level respond well to conservative treatment. For those patients who do require surgery for lumbar disk herniation, the reviewed procedures of nerve root decompression caused by disk herniation is favorable. Results of studies varied from 60–90% success rates. Disk surgery has progressively evolved in the direction of decreasing invasiveness. Each surgical procedure is not without possible complications, which can lead to chronic low back pain and restricted lifestyle.
Prevention
Proper exercises to strengthen the lower back and abdominal muscles are key in preventing excess stress and compressive forces on lumbar disks. Good posture will help prevent problems on cervical, thoracic, and lumbar disks. A good flexibility program is critical for prevention of muscle and spasm that can cause an increase in compressive forces on disks at any level. Proper lifting of heavy objects is important for all muscles and levels of the individual disks. Good posture in sitting, standing, and lying down is helpful for the spine. Losing weight, if needed, can prevent weakness and unnecessary stress on the disks caused by obesity . Choosing proper footwear may also be helpful to reduce the impact forces to the lumbar disks while walking on hard surfaces. Wearing special back support devices may be helpful if heavy lifting is required with combinations of twisting.
Resources
BOOKS
Beers, Mark H. et al. The Merck Manual of Diagnosis and Therapy Whitehouse Station, NJ: Merck, 1999.
Current Medical Diagnosis & Treatment 2001. Ed. Lawrence M. Tierney et al. New York: Lange, 2001.
Fauci, Anthony S. Harrison's Principles of Internal Medicine. New York: McGraw-Hill, 1998.
Ferri, Fred F. Ferri's Clinical Advisor. St.Louis: Mosby, 2001.
PERIODICALS
Humphreys, S. Craig et al. "Clinical Evaluation and Treatment Options for Herniated Lumbar Disc." American Family Physician 59 (1999).
McCall, I.W. "Lumbar Herniated Disks." Radiol Clin North Am 38 (200).
Miyamoto H. et al. "The Role of Cyclooxygenase-2 and Inflammatory Cytokines in Pain Induction of Herniated Lumbar intervertebral Disc." Kobe Journal of Medical Science 46 (2000).
Patel, Atul T. et al. "Diagnosis and Management of Acute Low Back Pain." American Family Physician 61 (2000).
Pui M.H. et al. "Value of Magnetic Resonance Myelography in the Diagnosis of Disk Herniation and Spinal Stenosis." Australasia Radiology 44 (2000).
Vanichkachorn, J.S. et al. "Thoracic Disk Disease: Diagnosis and Treatment." Journal of the American Academy of Orthopedic Surgery 8 (2000).
OTHER
FreedomQuest Inc. "Acupuncture." 1998. <http://acupuncture.com/Acup/AcuInd.htm>.
Medical Strategies Inc. (MSI). "Back Pain." 1993-1998. Healthtouch Online. <http://www.healthtouch.com>.
ORGANIZATIONS
American Chronic Pain Association. P.O. Box 850, Rocklin, CA 95677-0850. 1-916-632-0922. <http://www.theacpa.org>.
National Chronic Pain Outreach Association. P.O. Box 274, Millboro, VA 24460. 1-540-862-9437. [email protected].
Mark Mitchell
Herniated Disk
Herniated Disk
Definition
Disk herniation is a rupture of fibrocartilagenous material (annulus fibrosis) that surrounds the intervertebral disk. This rupture involves the release of the disk's center portion containing a gelatinous substance called the nucleus pulposus. Pressure from the vertebrae above and below may cause the nucleus pulposus to be forced outward, placing pressure on a spinal nerve and causing considerable pain and damage to the nerve. This condition most frequently occurs in the lumbar region and is also commonly called herniated nucleus pulposus, prolapsed disk, ruptured intervertebral disk, or slipped disk.
Description
The spinal column is made up of 26 vertebrae that are joined together and permit forward and backward bending, side bending, and rotation of the spine. Five distinct regions comprise the spinal column, including the cervical (neck) region, thoracic (chest) region, lumbar (low back) region, sacral and coccygeal (tail-bone) region. The cervical region consists of seven vertebrae, the thoracic region includes 12 vertebrae, and the lumbar region contains five vertebrae. The sacrum is composed of five fused vertebrae, which are connected to four fused vertebrae forming the coccyx. Intervertebral disks lie between each adjacent vertebra.
Each disk is composed of a gelatinous material in the center, called the nucleus pulposus, surrounded by rings of a fiberous tissue (annulus fibrosus). In disk herniation, an intervertebral disk's central portion herniates or slips through the surrounding annulus fibrosus into the spinal canal, putting pressure on a nerve root. Disk herniation most commonly affects the lumbar region between the fifth lumbar vertebra and the first sacral vertebra. However, disk herniation can also occur in the cervical spine. The incidence of cervical disk herniation is most common between the fifth and sixth cervical vertebrae. The second most common area for cervical disk herniation occurs between the sixth and seventh cervical vertebrae. Disk herniation is less common in the thoracic region.
Predisposing factors associated with disk herniation include age, gender, and work environment. The peak age for occurrence of disk herniation is between 20-45 years of age. Studies have shown that males are more commonly affected than females in lumbar disk herniation by a 3:2 ratio. Prolonged exposure to a bent-forward work posture is correlated with an increased incidence of disk herniation.
There are four classifications of disk pathology:
- A protrusion may occur where a disk bulges without rupturing the annulus fibrosis.
- The disk may prolapse where the nucleus pulposus migrates to the outermost fibers of the annulus fibrosis.
- There may be a disk extrusion, which is the case if the annulus fibrosis perforates and material of the nucleus moves into the epidural space.
- The sequestrated disk may occur as fragments from the annulus fibrosis and nucleus pulposus are outside the disk proper.
Causes and symptoms
Any direct, forceful, and vertical pressure on the lumbar disks can cause the disk to push its fluid contents into the vertebral body. Herniated nucleus pulposus may occur suddenly from lifting, twisting, or direct injury, or it can occur gradually from degenerative changes with episodes of intensifying symptoms. The annulus may also become weakened over time, allowing stretching or tearing and leading to a disk herniation. Depending on the location of the herniation, the herniated material can also press directly on nerve roots or on the spinal cord, causing a shock-like pain (sciatica) down the legs, weakness, numbness, or problems with bowels, bladder, or sexual function.
Diagnosis
Several radiographic tests are useful for confirming a diagnosis of disk herniation and locating the source of pain. These tests also help the surgeon indicate the extent of the surgery needed to fully decompress the nerve. X rays show structural changes of the lumbar spine. Myelography is a special x ray of the spine in which a dye or air is injected into the patient's spinal canal. The patient lies strapped to a table as the table tilts in various directions and spot x rays are taken. X rays showing a narrowed dye column in the intervertebral disk area indicate possible disk herniation.
Computed tomography scan (CT or CAT scans) exhibit the details of pathology necessary to obtain consistently good surgical results. Magnetic resonance imaging (MRI) analysis of the disks can accurately detect the early stages of disk aging and degeneration. Electomyograms (EMGs) measure the electrical activity of the muscle contractions and possibly show evidence of nerve damage. An EMG is a powerful tool for assessing muscle fatigue associated with muscle impairment with low back pain.
Treatment
Drugs
Unless serious neurologic symptoms occur, herniated disks can initially be treated with pain medication and up to 48 hours of bed rest. There is no proven benefit from resting more than 48 hours. Patients are then encouraged to gradually increase their activity. Pain medications, including antiinflammatories, muscle relaxers, or in severe cases, narcotics, may be continued if needed.
Epidural steroid injections have been used to decrease pain by injecting an antiinflammatory drug, usually a corticosteroid, around the nerve root to reduce inflammation and edema (swelling). This partly relieves the pressure on the nerve root as well as resolves the inflammation.
Physical therapy
Physical therapists are skilled in treating acute back pain caused by the disk herniation. The physical therapist can provide noninvasive therapies, such as ultrasound or diathermy to project heat deep into the tissues of the back or administer manual therapy, if mobility of the spine is impaired. They may help improve posture and develop an exercise program for recovery and long-term protection. Appropriate exercise can help take pressure off inflamed nerve structures, while improving overall posture and flexibility. Traction can be used to try to decrease pressure on the disk. A lumbar support can be helpful for a herniated disk at this level as a temporary measure to reduce pain and improve posture.
Surgery
Surgery is often appropriate for conditions that do not improve with the usual treatment. In this event, a strong, flexible spine is important for a quick recovery after surgery. There are several surgical approaches to treating a herniated disk, including the classic discectomy, microdiscectomy, or percutanteous discectomy. The basic differences among these procedures are the size of the incision, how the disk is reached surgically, and how much of the disk is removed.
Discectomy is the surgical removal of the portion of the disk that is putting pressure on a nerve causing the back pain. In the classic disectomy, the surgeon first enters through the skin and then removes a bony portion of the vertebra called the lamina, hence the term laminectomy. The surgeon removes the disk material that is pressing on a nerve. Rarely is the entire lamina or disk entirely removed. Often, only one side is removed and the surgical procedure is termed hemi-laminectomy.
In microdiscectomy, through the use of an operating microscope, the surgeon removes the offending bone or disk tissue until the nerve is free from compression or stretch. This procedure is possible using local anesthesia. Microsurgery techniques vary and have several advantages over the standard discectomy, such as a smaller incision, less trauma to the musculature and nerves, and easier identification of structures by viewing into the disk space through microscope magnification.
Percutaneous disk excision is performed on an outpatient basis, is less expensive than other surgical procedures, and does not require a general anesthesia. The purpose of percutaneous disk excision is to reduce the volume of the affected disk indirectly by partial removal of the nucleus pulposus, leaving all the structures important to stability practically unaffected. In this procedure, large incisions are avoided by inserting devices that have cutting and suction capability. Suction is applied and the disk is sliced and aspirated.
Arthroscopic microdiscectomy is similar to percutaneous discectomy, however it incorporates modified arthroscopic instruments, including scopes and suction devices. A suction irrigation of saline solution is established through two entry sites. A video discoscope is introduced from one site and the deflecting instruments from the opposite side. In this way, the surgeon is able to search and extract the nuclear fragments under direct visualization.
Laser disk decompression is performed using similar means as percutaneous excision and arthroscopic microdiscectomy, however laser energy is used to remove the disk tissue. Here, laser energy is percutanteously introduced through a needle to vaporize a small volume of nucleus pulposus, thereby dropping the pressure of the disk and decompressing the involved neural tissues. One disadvantage of this procedure is the high initial cost of the laser equipment. It is important to realize that only a very small percentage of people with herniated lumbar disks go on to require surgery. Further, surgery should be followed by appropriate rehabilitation to decrease the chance of reinjury.
Chemonucleolysis
Chemonucleolysis is an alternative to surgical excision. Chymopapain, a purified enzyme derived from the papaya plant, is injected percutaneously into the disk space to reduce the size of the herniated disks. It hydrolyses proteins, thereby decreasing water-binding capacity, when injected into the nucleus pulposus inner disk material. The reduction in size of the disk relieves pressure on the nerve root.
Spinal fusion
Spinal fusion is the process by which bone grafts harvested from the iliac crest (thick border of the ilium located on the pelvis) are placed between the intervertebral bodies after the disk material is removed. This approach is used when there is a need to reestablish the normal bony relationship between the vertebrae. A total discectomy may be needed in some cases because lumbar spinal fusion can help prevent recurrent lumbar disk herniation at a particular level.
Alternative treatment
Acupuncture involves the use of fine needles inserted along the pathway of the pain to move energy locally and relieve the pain. An acupuncturist determines the location of the nerves affected by the herniated disk and positions the needles appropriately. Massage therapists may also provide short-term relief from a herniated disk. Following manual examination and x-ray diagnosis, chiropractic treatment usually includes manipulation to correct muscle and joint malfunctions, while care is taken not to place an additional strain on the injured disk. If a full trial of conservative therapy fails, or if neurologic problems (weakness, bowel or bladder problems, and sensory loss) develop, the next step is usually evaluation by an orthopedic surgeon.
KEY TERMS
Annulus fibrosis— The outer portion of the intervertebral disk made primarily of fibrocartilage rings.
Epidural space— The space immediately surrounding the outermost membrane of the spinal cord.
Excision— The process of excising, removing, or amputating.
Fibrocartilage— Cartilage that consists of dense fibers.
Nucleus pulposus— The center portion of the intervertebral disk that is made up of a gelatinous substance.
Percutaneous— Performed through the skin.
Prognosis
Only 5-10% of patients with unrelenting sciatica and neurological involvement, leading to chronic pain of the lumbar spine, need to have a surgical procedure performed. This strongly suggests that many patients with herniated disks at the lumbar level respond well to conservative treatment. For those patients who do require surgery for lumbar disk herniation, the reviewed procedures of nerve root decompression caused by disk herniation is favorable. Results of studies varied from 60-90% success rates. Disk surgery has progressively evolved in the direction of decreasing invasiveness. Each surgical procedure is not without possible complications, which can lead to chronic low back pain and restricted lifestyle.
Prevention
Proper exercises to strengthen the lower back and abdominal muscles are key in preventing excess stress and compressive forces on lumbar disks. Good posture will help prevent problems on cervical, thoracic, and lumbar disks. A good flexibility program is critical for prevention of muscle and spasm that can cause an increase in compressive forces on disks at any level. Proper lifting of heavy objects is important for all muscles and levels of the individual disks. Good posture in sitting, standing, and lying down is helpful for the spine. Losing weight, if needed, can prevent weakness and unnecessary stress on the disks caused by obesity. Choosing proper footwear may also be helpful to reduce the impact forces to the lumbar disks while walking on hard surfaces. Wearing special back support devices may be helpful if heavy lifting is required with combinations of twisting.
Resources
OTHER
"Back Pain." Healthtouch Online Page. 〈http://www.healthtouch.com〉.
Herniated Disk
Herniated disk
Definition
Disk herniation is a breakdown of a fibrous cartilage material (annulus fibrosus) that makes up the intervertebral disk. The annulus fibrosus surrounds a soft gel-like substance in the center of the disk called the nucleus pulposus. Pressure from the vertebrae above and below may cause the nucleus pulposus to be forced against the sides of the annulus. The constant pressure of the nucleus against the sides of the annulus will cause the fibers of the annulus to break down. As the fibers of the annulus break down, the nucleus will push toward the outside of the annulus and cause the disk to bulge in the direction of the pressure. This condition most frequently occurs in the lumbar region and is also commonly called a herniated nucleus pulposus, prolapsed disk, ruptured disk, or a slipped disk.
Description
The spinal column is made up of 24 vertebrae that are joined together and permit forward and backward bending, side bending, and rotation of the spine. There are seven cervical (neck), twelve thoracic (chest region), and five lumbar (low back) vertebra. There are intervertebral disks between each of the 24 vertebrae as well as a disk between the lowest lumbar vertebrae and the large bone at the base of the spine called the sacrum.
Disk herniation most commonly affects the lumbar region. However, disk herniation can also occur in the cervical spine. The incidence of cervical disk herniation is most common between the fifth and sixth cervical vertebrae. The second most common area for cervical disk herniation occurs between the sixth and seventh cervical vertebrae. Disk herniation is uncommon in the thoracic region.
The peak age for occurrence of disk herniation is between 20 and 45 years of age. Studies have shown that males are more commonly affected than females in lumbar disk herniation by a 3:2 ratio. Long periods of sitting or a bent-forward work posture may lead to an increased incidence of disk herniation.
There are four classifications of disk pathology:
- A protrusion occurs when a disk bulges without rupturing the annulus fibrosus.
- A prolapse occurs when the nucleus pulposus pushes to the outermost fibers of the annulus fibrosus but does not break through them.
- An extrusion occurs when the outermost layer of the annulus fibrosus is torn and the material of the nucleus moves into the epidural space.
- A sequestration occurs when fragments from the annulus fibrosus or the nucleus pulposus have broken free and lie outside the confines of the disk.
Causes & symptoms
Any direct or, forceful in a vertical direction pressure on the disks can cause the disk to push its nucleus into the fibers of the annulus or into the intervertebral canal. A herniated disk may occur suddenly from lifting, twisting, or direct injury, but more often it will occur from constant compressive loads over time. There may be a single incident that causes symptoms to be felt, but very often the disk was already damaged and bulging prior to any one particular incident.
Depending on the location of the herniation, the herniated material can also press directly on nerve roots or on the spinal cord. Pressure on the nerve roots or spinal cord may cause a shock-like pain sensation down the arms if the herniation is in the cervical vertebrae or down the legs if the herniation is in the lumbar region.
In the lumbar region a herniation that presses on the nerve roots or the spinal cord may also cause weakness, numbness, or problems with bowels, bladder, or sexual function. It is unclear if a herniated disk causes pain by itself without pressing on neurological structures. It is likely that irritation of the disk or the adjacent nerve roots may cause muscle spasm and pain in the region of the disk pathology.
Diagnosis
Several radiographic tests are useful for confirming a diagnosis of disk herniation and locating the source of pain. X rays show structural changes of the lumbar spine. Myelography is a special x ray of the spine in which a dye or air is injected into the patient's spinal canal. The patient lies strapped to a table as the table tilts in various directions and spot x rays are taken. X rays showing a narrowed dye column in the intervertebral disk area indicate possible disk herniation.
Computed tomography scan (CT scans) exhibit the details of pathology necessary to obtain consistently good treatment results. Magnetic resonance imaging (MRI) analysis of the disks can accurately detect the early stages of disk aging and degeneration. Electromyograms (EMGs) measure the electrical activity of the muscle contractions and possibly show evidence of nerve damage.
A number of physical examination procedures may be used to determine if a herniated disk is pressing on a nerve root. While these tests may not identify the definitive presence of a herniated disk, they are very useful for
indicating if there is pressure on a nerve root from some structure such as a herniated disk. The straight leg raise test may be used to identify pressure on nerve roots in the lumbar region while the Spurling's test (involving neck motion) may be used to identify compression of nerve roots in the cervical region. Compression of nerve roots in the cervical, thoracic, or lumbar regions may be apparent with the slump test.
Treatment
It is unclear if herniated disks cause pain themselves, or if they must press on a nerve root to cause pain. Pain may also occur with herniated disks as a result of mechanical or neurological irritation of surrounding structures such as muscles, tendons, ligaments, or joint capsules. Therefore, many treatment strategies will be primarily focused on managing symptoms that occur in conjunction with a herniated disk. Unless a serious neurological problem exists, most symptoms of a herniated disk will resolve on their own. Yet, the interventions listed below may greatly speed the time required to resolve symptoms associated with a herniated disk.
Chiropractic manipulations are often used to treat herniated disks. There is often significant joint restriction that accompanies a herniated disk and the manipulative therapy is effective at helping to mobilize movement restrictions in the spine. Mobilizing the spine will help the patient get back to moderate activity levels sooner. The earlier an individual can return to moderate activity levels, the quicker they can expect a resolution of their symptoms. Chiropractic manipulations are generally done with a greater frequency when a condition is in an acute stage. The frequency of treatments will be reduced as the condition improves.
Osteopathic therapy, considered by some to be an alternative treatment, may use manipulations or manual therapy techniques very similar to those of chiropractors. However, osteopathic physicians often employ more manual therapy techniques that focus on the role of the muscles and other soft tissues in producing pain sensations with herniated disks. Osteopathic physicians may also recommend use of the same medications prescribed by allopathic physicians. Some osteopaths also perform surgery for herniated disks.
Acupuncture involves the use of fine needles inserted along the pathway of the pain to move energy through the body and relieve the pain. Neurological irritation is considered to be a frequent source of pain with a herniated disk. Many believe acupuncture is particularly effective for pain management and addressing this neurological irritation. Acupuncture can also help break the cycle of pain and muscle spasm that often accompanies a herniated disk.
Massage therapists focus on muscular reactions to the herniated disk. Neurological irritation that comes with a herniated disk will often cause excessive muscle spasms in the lower back muscles. These spasms will perpetuate dysfunctional movements in the joints of the spine and may exaggerate compressive forces on the intervertebral disk. By relaxing the muscles, massage therapists will attempt to manage the symptoms of disk herniation until proper movement can be restored. Proper movement and avoidance of aggravating postures, like sitting for long periods, will often be a great help in completely resolving the symptoms.
Allopathic treatment
Unless serious neurologic symptoms occur, herniated disks can initially be treated with pain medication. Pain medications, including anti-inflammatories, muscle relaxants, or in severe cases, narcotics, may be used if needed. Bed rest is sometimes prescribed. However, bed rest is frequently discouraged as a treatment for herniated disks unless movement is severely painful. It has become apparent that prolonged periods of bed rest may aggravate symptoms, slow down the healing time, and cause other complications.
Epidural steroid injections have been used to decrease pain by injecting an anti-inflammatory drug, usually a corticosteroid, around the nerve root to reduce inflammation and edema (swelling). This treatment partly relieves the pressure on the nerve root as well as resolves the inflammation.
Physical therapists are skilled in treating acute back pain caused by disk herniation. The physical therapist can provide noninvasive therapies, such as ultrasound or diathermy, to project heat deep into the tissues of the back or administer manual therapy, if mobility of the spine is impaired. They may help improve posture and develop an exercise program for recovery and long-term protection. Traction can be used to decrease pressure on the disk. A lumbar support can be helpful for a herniated disk at this level as a temporary measure to reduce pain and improve posture.
Surgery may be used for conditions that do not improve with conservative treatment. There are several surgical approaches to treating a herniated disk. A number of surgical procedures may be used to remove a portion of the intervertebral disk that may be pressing on a nerve root. When a portion of the disk is removed through a surgical procedure it is called a discectomy. Sometimes a spinal fusion will be performed after disk material has been removed. In this process a portion of bone is taken from the pelvis and placed between the bodies of the vertebrae. A spinal fusion will limit motion at that vertebral segment, but may be helpful in the event that significant disk material has been removed.
Chemonucleolysis is an alternative to surgical removal of the disk. Chymopapain, a purified enzyme derived from the papaya plant, is injected into the disk space to reduce the size of the herniated disks. The reduction in size of the disk relieves pressure on the nerve root. In 2002, Tokyo doctors produced evidence that a growth factor called vascular endothelial growth factor (VEGF) may speed up the process of injured disk resorption.
In September 2002, a noted orthopedic and spine authority named John Engelhardt became the first American to receive an artificial disk replacement (using the Bristol disk) in an operation in Switzerland. The artificial disk technology was still in clinical trials in the United States and was not expected to be approved until about 2005 or later.
Expected results
Only a small percentage of patients with unrelenting neurological involvement, leading to chronic pain of the spine, need to have a surgical procedure performed. This fact strongly suggests that many patients with herniated disks respond well to conservative treatment. Alternative therapies can play a significant role in managing the pain and discomfort for the majority of patients with a herniated disk. In fact, magnetic resonance imaging (MRI) studies of the lumbar spine have indicated that many people without any back pain at all have herniated disks. This finding means it is unclear what role the herniated disk plays in many back pain cases. For many of these patients, proper symptom management of pain and improvement in joint motion and mobility through manual therapies will be enough to fully resolve their symptoms. For those patients who do require surgery, options are available for newer and less invasive procedures that will allow a quicker healing time.
Prevention
Proper exercises to strengthen the lower back and abdominal muscles are key in preventing excess stress and compressive forces on lumbar disks. Good posture will help prevent problems on cervical, thoracic, and lumbar disks. A good flexibility program is critical for prevention of muscle spasm that can cause an increase in compressive forces on disks at any level. Proper lifting of heavy objects is important for all muscles and levels of the individual disks. Good posture in sitting, standing, and lying down is helpful for the spine. Losing weight, if needed, can prevent weakness and unnecessary stress on the disks caused by obesity .
Such alternative treatments as chiropractic, massage therapy , or acupuncture may play a very important role in prevention of herniated disk problems. Regular use of these approaches may help maintain proper muscular tone and reduce the cumulative effects of postural strain that may lead to the development of disk problems.
Resources
BOOKS
Hammer, W. Functional Soft Tissue Examination and Treatment by Manual Methods, 2nd ed. Gaithersburg, MD: Aspen, 1999.
Kessler, R.M. Management of Common Musculoskeletal Disorders: Physical Therapy Principles and Methods. Philadelphia: J.B. Lippincott Co., 1990.
Liebenson, C. Rehabilitation of the Spine. Baltimore: Williams & Wilkins., 1996.
Maciocia, G. Foundations of Chinese Medicine. London: Churchill Livingstone, 1989.
Magee, D.J. Orthopedic Physical Assessment. Philadelphia: W.B. Saunders, 1992.
Waddell, G. The Back Pain Revolution. London: Churchill Livingstone, 1998.
PERIODICALS
"Factor Could Speed Absorption of Herniated Disks." Pain & Central Nervous System Week (July 29, 2002): 2.
"Industry Authority Becomes First American to Receive Artificial Cervical Disk." Medical Devices & Surgical Technology Week (September 22, 2002): 3.
Jensen, M., et al. "Magnetic Resonance Imaging of the Lumbar Spine in People Without Back Pain." New England Journal of Medicine 331 (July 14, 1994): 69.
Whitney Lowe
Teresa G. Odle
Slipped Disk
Slipped Disk
How Is Slipped Disk Diagnosed?
What Is the Treatment for Slipped Disk?
Slipped disk is a condition in which a disk in the spinal column becomes displaced from its normal position in the spine and presses on the spinal nerves, causing pain and sometimes muscle weakness.
KEYWORDS
for searching the Internet and other reference sources
Skeletal disorders
Spine
What Is a Slipped Disk?
The spine is made up of bones called vertebrae (VUR-te-bray) that protect the delicate spinal cord. These vertebrae are separated from each other and cushioned by disks. The disks contain a soft inner layer and a tough outer layer. If the outer layer tears, the soft inner layer can push out and put pressure on the spinal nerves. This can cause severe pain as well as muscular weakness. Slipped disks are also called “herniated,” “protruded,” and “bulging.”
Most slipped disks occur in the lower back. However, slipped disks can occur in any part of the spine, including the neck.
What Causes Slipped Disks?
In most cases, the condition develops gradually over a number of years. A person may be totally unaware that anything is wrong, until the disk begins to cause pain. There are a small number of cases of slipped disk that occur to people who have made a sudden difficult movement, such as lifting a heavy object or making a sudden awkward movement. Slipped disks can also be the result of normal wear and tear on the disks due to aging.
How Common Is Slipped Disk?
Slipped disk is a fairly common disorder that happens mainly to people between the ages of 30 and 40. However, it can occur in younger people and even in children. After the age of 40, disks become more stable because extra tissue forms around them. Between the ages of 30 to 40, disks tend to lose fluid and become less resistant to pressures put on them. Slipped disk is more common in men than in women. People of either sex, however, who sit for long periods of time are more susceptible to the condition.
How Is Slipped Disk Diagnosed?
A person suffering from severe, sudden back pain should be evaluated by a physician to determine if he or she has a slipped disk, particularly if there is muscular weakness or pain and numbness in the legs or feet. The doctor administers nerve-reflex and muscle-strength tests after taking a personal history of the patient.
Among the tests used to locate and confirm a diagnosis, x-rays and other imaging tests may be performed. Another test, an electromyogram (e-LEK-tro-MY-o-gram) can measure the amount of electrical activity in the muscles and help determine how much muscle or nerve damage the patient has.
What Is the Treatment for Slipped Disk?
Total bed rest used to be prescribed for 2 weeks. Doctors now believe that this much bed rest does not help, and patients may be told to stay in bed 2 to 3 days. Medications are given to help relax muscle spasms and to relieve pain. After their initial symptoms have improved, patients are given certain exercises to strengthen the muscles of the back and abdomen and they are told to avoid twisting the spine. Lifting should be done by bending the knees first and keeping the spine upright. Most patients recover within 3 months.
However, if these treatments are not successful, surgery may be necessary. Disk surgery involves removing a part of the disk that has slipped against a nerve. Exercise, weight management, and lifestyle changes are recommended following surgery to avoid a recurrence of the injury.
See also
Sciatica