Herniated Lumbar Disks

The vertebrae (bones of the spine) are cushioned by blocks or pads of tissue called disks. These disks are round and flat and made up of 2 parts: the annulus (a tough outer capsule or ring) and the nucleus (an inner, spongy core of jellylike material). When these disks are healthy, they act as shock absorbers for the spine and are essential in keeping the spine flexible. The normal, everyday pressures on the spine force the outer surface to bulge slightly. When these disks are damaged from an injury, normal wear and tear, or disease, they may bulge abnormally or rupture (break open). When a damaged disk bulges abnormally or ruptures, it is called a herniated (slipped) disk. Herniated disks can occur in any part of the spine but most often affect the lumbar spine (lower back). The abnormal disk material can place pressure on the adjacent spinal cord or nerve roots, resulting in pain, numbness, or weakness in areas of the lower back, buttocks, and legs. The November 22/29, 2006, issue of JAMA includes 2 articles about surgery for herniated disks.


RISK FACTORS FOR A HERNIATED DISK
Natural aging process—ongoing loss of water and proteins from the disk
Genetic (inherited) predisposition—an accelerated degeneration of disk materials
Obesity—excessive body weight places added stress on the spine
Lack of exercise—results in a loss of trunk muscle strength and diminished spine support
Work activities—long periods of sitting, lifting or pulling heavy objects, frequent bending or twisting, heavy physical exertion, repetitive motions, or exposure to constant vibration
Smoking—deprives blood flow and nutrients needed for disk repairs
History of back injury, previous herniated disk, or prior back surgery
CONSULT YOUR DOCTOR IF
A moderate injury causes immediate numbness or weakness in one or both legs
You have shooting leg pains with coughing, sneezing, or straining
Leg pain is accompanied by persistent weakness, tingling, or numbness
Back pain persists or builds in intensity over a few weeks' duration
Back pain is accompanied by pain during urination
You experience severe deep back muscle pain and muscle spasms
You have loss of bowel or bladder control
DIAGNOSIS AND TREATMENT OPTIONS
Diagnosis is based on a complete medical history accompanied by a thorough physical examination performed by your doctor. Tests involving imaging of the spine are sometimes done. Treatments can include oral medications, drug injections, and physical therapy. Most back and leg pain will resolve with these simple measures. For persons who have chronic pain and disability, surgical options may be considered.
FOR MORE INFORMATION
American Academy of Family Physicians http://familydoctor.org/341.xml
American Association of Orthopaedic Surgeons http://www.aaos.org/
American Association of Neurological Surgeons http://www.neurosurgerytoday.org/what/patient_e/herniated.asp

Spinal Stenosis

Spinal stenosis is a term used to describe a narrowing of the spinal canal, which contains the spinal cord and emerging nerve roots. It can occur in any portion of the spine. Because of limited space, changes in the bone (vertebral bodies) or soft tissues (spinal ligaments) can result in compression of the affected spinal cord and blood vessels. This narrowing can be congenital (genetic) or acquired (arthritis, trauma, bone disease, tumor) or a combination of both. Stenosis can be classified by location: central (involving the spinal cord) or lateral (affecting the nerve roots). Cord compression can also occur in patients with advanced cancer. The February 27, 2008, issue of JAMA includes an article about treatment options for cord compression due to metastatic cancer.


CONDITIONS THAT RESULT IN SPINAL STENOSIS
Osteophytes—formation of bony spurs associated with osteoarthritis
Herniated disk—protrusion of a cartilage disk between vertebrae
Malignancy—cancer
Scarring and inflammation of supporting spinal ligaments
Abscess—localized infection
Spondylolisthesis—a shift or abnormal stacking of 2 vertebral bodies
Congenital—genetic predisposition, which results in a developmentally small spinal canal
Systemic bone diseases (such as Paget disease of bone)

SYMPTOMS OF SPINAL STENOSIS
Pseudoclaudication—difficulty in walking
Paresthesia—abnormal skin sensations such as numbness and tingling
Muscle weakness
Localized or radiating pain
Loss of bladder or bowel control

DIAGNOSIS AND TREATMENT
Spinal stenosis can be diagnosed based on the history of symptoms, a physical examination, and imaging tests. Once the diagnosis is confirmed, treatment may be conservative (rest, steroid injections, medications, and exercise) or surgical. As symptoms become debilitating, surgery may be considered a treatment option. The main goal of any surgical procedure is to remove pressure from the spinal cord or nerve roots. This means that the tube of the spinal canal must be made larger by removing excess bone, ligaments, and abnormal tissues that are compressing the nerve roots. This type of surgical procedure is termed a decompressive laminectomy (removing a portion of the vertebral body and surrounding soft tissue). If individuals have both spinal stenosis and instability of the spine, the surgical procedure should include a decompression coupled with a spinal fusion (use of instrumentation supplemented with bone graft to maintain the structural support of the spinal column).

FOR MORE INFORMATION
American Association of Neurological Surgeons (AANS) http://www.neurosurgery.org/
American Association of Orthopaedic Surgeons (AAOS) http://www.aaos.org/
North American Spine Society (NASS) http://www.spine.org/