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Anatomy of the Spine

The 24 bones of your spine (vertebrae) and the cushioning discs between them are arranged in three natural curves:

  1. The Cervical Spine (neck): the top seven vertebrae
  2. The Thoracic Spine (chest): the middle twelve vertebrae
  3. The Lumbar Spine (lower back): the bottom five vertebrae

Attached to the vertebrae are muscles, tendons and a group of strong bands called ligaments. Together they support the spinal column and help protect its delicate nerves.

Your spinal column enables you to walk upright. It is the central support for your upper body and carries the weight of your head, chest and arms. The vertebrae in the lumbar (or lower back) portion of your spine carry the majority of this weight. The constant pressure from this weight, even when you are simply sitting in a chair, is what usually leads to problems associated with the lower back.

The bony vertebrae of your spinal column are separated from one another by “pads” of tough cartilage called intervertebral discs. These discs act like “shock absorbers” during activity, allowing the spine to move freely. When these curves are in their normal alignment, your body is in a balanced position. This spreads your weight evenly throughout the vertebrae and discs, so you are less likely to have strain and injury.

The center of each intervertebral disc is made up of a gelatin-like substance surrounded by a fiber-like outer lining. As your body ages, the disc’s nucleus begins to stiffen. This reduces the flexibility of the discs and increases the chance they may “rupture,” especially in the lumbar spine which carries so much of the body’s weight.

The spinal cord, which begins at the base of the brain and runs within the spinal canal, ends in the lumbar spine area in a bundle of nerves known as the cauda equina. The spinal canal runs through the center of the spinal column and protects the spinal cord and other delicate spinal nerves.

At each vertebrae level, a pair of nerves branch off from the spinal cord or the cauda equina, one to the left and one to the right. These spinal nerve roots are part of the body’s “electrical” system, carrying the “current” for sensation and movement to specific parts of the body. The nerve roots are protected by an “insulated” covering in the same way a “live” electrical wire is coated to prevent direct contact with the core wires. A nerve root damaged by a ruptured disc may have all or part of its “insulation” rubbed off at the point of injury. Prior to surgery, there is no way of telling how much has rubbed off or how much damage has been done to the nerve.

What is Neurosurgery?

Neurosurgery is the art and science of the surgical treatment of the brain, spine and nerves. The physician who surgically treats these diseases is a neurosurgeon. Neurosurgeons undergo between six to eight years of highly specialized training which allows them to become experts in this field of medicine.

Neurosurgeons treat disorders of the brain such as tumors, trauma, brain hemorrhage, aneurysms, abnormal vessels and other disorders that involve surgery of the head. Neurosurgeons also have expert knowledge of spinal disorders, including the surgical treatment of herniated discs, spinal fractures, bone tumors, infections of the spine, spinal cord tumors and degenerative conditions of the spine. Neurosurgeons also treat nerve disorders, such as carpal tunnel syndrome and other nerve entrapment syndromes.

A very select group of neurosurgeons perform laser surgery and laparoscopic disc surgery – two breakthrough methods of surgery proven to be less invasive and traumatic to the patient. Dr. Theofilos is one of the few neurosurgeons in the country trained to perform these minimally invasive techniques. It should be noted not all patients who visit a neurosurgeon require surgery. Neurosurgeons work with patients to seek out the most conservative methods available to treat their particular illness. Conservative methods are often successful in achieving patient recovery and surgery is avoided.

What Causes Back Pain: A Layperson’s Guide

Injury, the normal aging process, or early aging due to misuse, can cause certain spinal problems. Then the discs or bones press on the roots of the spinal nerves, causing symptoms such as pain, stiffness, tingling and numbness.

Using your body incorrectly overstresses the three natural curves and results in an unbalanced spine. Too much flexion (forward bending) or extension (backward arching) puts extra pressure on the spine. As a result, the vertebrae and discs wear out (degenerate) faster than normal, leading to bulging or ruptured discs, arthritis and instability.

Mechanical pain is often called back strain, because it is linked with the movement of the spine. This type of pain occurs when injury to the spine’s discs, facet joints, ligaments or muscles results in inflammation. These conditions include fractures of the vertebra, muscle strains in the paraspinal muscles, ligament injures in the spine and wear and tear of the spine’s joints and discs.

Compressive pain is a result of pressure or irritation on the spinal cord or nerves that leave the spine. Usually, this pressure or irritation causes pain, numbness and muscle weakness where the nerve travels. It can be helpful to understand which part of the spine is causing your back pain and whether the pain is from a compressive or mechanical type problem.

Osteoarthritis is caused by a permanent breakdown of the cartilage inside the affected joint. Cartilage is the material inside the joint that cushions the bones of the joints from impact and allows smooth, gliding motions. Because damaged cartilage cannot repair itself, it begins to fray, making it less flexible and more prone to injury. Over time, the cartilage can wear away completely, causing the bony surfaces of the joint to rub directly against one another. Eventually, the joint becomes worn away, and bone spurs develop around the joint. Sometimes the facet joints are the main cause of back pain. Pressure overload on the facet joints is probably caused by degeneration of the intervertebral discs. As the discs degenerate, they wear down and begin to collapse. This narrows the space between each pair of vertebrae and affects the way the facet joints line up. When this occurs, it places too much pressure on the articular cartilage surface of the facet joint. The excessive pressure leads to damage of the articular surface, and eventually the cartilage begins to wear away. When facet joint arthritis gets bad enough, the cartilage and fluid that lubricate the facet joints are eventually destroyed as well, leaving bone rubbing on bone.

Radiculopathy is the medical term used to describe a “pinched nerve” in the spine when a nerve is irritated by something rubbing or pressing on the nerve. In some cases, such as a herniated (or ruptured) disc, there may also be a chemical reaction irritating the nerve. Chemicals released from inside the disc seem to irritate nerve tissue, causing pain and inflammation of the nerve. There may be numbness in the area where the nerve usually provides sensation or feeling. The key to understanding a radiculopathy is understanding your brain cannot tell where the problem really is. While the irritation or pressure on the nerve may be in your back, your brain thinks the pain is coming from your foot. In addition, the muscles the nerve usually controls may not work right. You may have weakness in the muscles, and the reflexes controlled by the muscles will not work.

Sciatica refers to the pain that travels from the sciatic nerve in the lumbar region into your buttocks, back of the thighs and sometimes calf and foot. The pain is typically caused by irritation of the nerve roots that join outside the spine to make up the sciatic nerve. Conditions that can cause sciatica are herniated discs, bone spurs, cancerous tumors growing into the nerves and fractures that put pressure on the nerves.

Spinal stenosis is a term commonly used to describe a narrowing of a portion of the spinal canal and is most common in the cervical and lumbar spine. Although there is some space between the spinal cord and the edges of the spinal canal, this space can be reduced by many conditions. If anything begins to narrow the spinal canal, the risk of irritation and injury of the spinal cord or nerves increases. Spinal stenosis usually occurs in older people after years of wear and tear or degeneration of the spine. This wear and tear results in changes in the structures around the spinal canal, such as thickening of the large ligaments that connect the vertebrae together, bone spurs around the facet joints and disc space, and bulging of the discs themselves. The lack of space can also cause the supply of blood and oxygen to the spinal cord to be reduced. When the spine needs more blood flow during increased activity, the blood vessels may not be able to swell to get more blood to the spine. This can lead to numbness and pain in the affected nerves. The nerves also lose some of their mobility when the space available to them is reduced. Other symptoms of spinal stenosis include a sensation of heaviness, weakness and pain when walking or standing for a long period. With rest, these symptoms often disappear.

Discogenic pain is a term back specialists use when referring to pain caused by a damaged intervertebral disc. As the disc begins to degenerate, movements that place stress on the disc can result in back pain that appears to come from the disc. It may also feel like the pain is coming from your buttock areas and even down into the upper thighs. The experience of feeling pain in an area away from the real spot causing the pain is common in many areas of the body, not just the spine.

A herniated disc occurs when the intervertebral disc’s outer fibers (the annulus) are damaged and the soft inner material of the nucleus pulposus ruptures out of its normal space. If the annulus tears near the spinal canal, the nucleus pulposus material can push into the spinal canal. This can cause too much pressure on the spinal cord and nerve roots and cause pain, weakness or numbness in the area of the body to which the nerve travels. For this reason, a herniated disc usually causes pain of the compressive type. Sometimes a herniated disc is referred to as a “slipped disc,” though the disc does not actually slip. In most cases, a herniated disc can be treated without surgery.

Spinal instability (spondylolisthesis) occurs when the disc degenerates and flattens, allowing the vertebrae to slip back and forth and eventually allowing a crack to develop. This motion irritates facet joints and nerves and creates or worsens stenosis.

Myofascial pain refers to muscle pain that occurs when muscles become stretched and inflamed. (Source: allaboutbackpain.com)

Boning Up on Osteoporosis: What you need to know

Osteoporosis is one of the body’s most insidious conditions that happens slowly, over years, and often neither doctor nor patient is aware of weakening bones until one snaps unexpectedly. It’s the primary cause of hip fracture, which can lead to permanent disability, loss of independence, and sometimes even death.

Osteoporosis leads to 1.5 million fractures, or breaks, per year, mostly in the hip, spine and wrist, with the cost of treatment estimated at $10 billion to $15 billion a year, according to the National Institutes of Health. It threatens 25 million Americans, mostly older women, but older men get it too. One in three women past 50 will suffer a vertebral fracture, according to the foundation.

Osteoporosis, which means “porous bones,” is a condition of excessive skeletal fragility resulting in bones breaking easily. A combination of genetic, dietary, hormonal, age-related, and lifestyle factors all contribute to this condition. Although some bone loss is expected as people age, osteoporosis is no longer viewed as an inevitable consequence of aging. Diagnosis, treatment and prevention need no longer wait until bones break.

Understanding Bone Density

The skeleton is like a retirement account for minerals, but in our skeletal “account” we can deposit bone faster than we withdraw it only during our first three decades. After that, withdrawals are greater than deposits, and all we can do is try to minimize the net loss. Osteoporotic fractures are the sign of the bankruptcy that occurs when too little bone is formed during youth, too much is lost later in life, or both.

“The upper limit of bone mass you can acquire is genetically determined,” says Mona S. Calvo, Ph.D., a calcium expert in the FDA’s Center for Food Safety and Applied Nutrition. “But even though you may be programmed for high bone mass, other factors can influence how much bone you end up with,” she says.

But there’s another reason. With the decline of the female hormone estrogen at menopause, usually around age 50, bone breakdown markedly increases. For several years, women lose bone two to four times faster than they did before menopause. The rate usually slows down again, but some women may continue to lose bone rapidly. By age 65, some women have lost half their skeletal mass.


Bone density tests are useful for confirming a diagnosis of osteoporosis if a person has already had a suspicious fracture, or for detecting low bone density so preventative steps can be taken. A newer technique for evaluating bone strength is ultrasound, and the FDA has approved several instruments for this purpose. “These machines use the same principles employed when using ultrasound to look at fetuses during pregnancy,” says Leo Lutwak, M.D., Ph.D., of the FDA’s division of radiology, abdominal, and radiological devices. “Although this measurement examines different properties of bone than do X-ray-based bone densitometers, the results are also useful for prediction of fracture.” The devices for ultrasound measurement are cheaper and easier to use. “Because they don’t use X-rays, they are safer and may be used for repeated examinations, even in pregnant women and children, so they provide a means for better public health practice,” Lutwak says.

Another new test provides an indicator of bone breakdown. In 1995, the FDA approved a simple, non-invasive biochemical test that detects in a urine sample a specific component of bone breakdown, called NTx. Clinical labs can get results in about 2 hours. The NTx test, marketed as Osteomark, can help physicians monitor treatment and identify fast losers of bone for more aggressive treatment, but the test doesn’t measure bone metabolism specifically, so it may not be used to diagnose osteoporosis.

Expanding Treatment Options

All drugs approved by the FDA at this time act by slowing the turnover of bone rather than stimulating new bone formation. Before 1995, the only choices were the hormones estrogen and calcitonin. While enthusiasm for new weapons against osteoporosis is warranted, one of the old ones is still considered by some to be the top choice. “If you think about what’s missing at menopause, it’s the hormones,” says Paula Stern, Ph.D., a pharmacologist at Northwestern University Medical School in Chicago.

Estrogen replacement therapy is the best prevention for the drop in bone mass at menopause, and there are now more ways to take it than ever before. But it’s not for everyone. Because estrogen increases the risk of certain cancers and other diseases, taking it may not be appropriate, or it may be given in combination with another female hormone, progesterone, which can also cause undesirable side effects. Women who can’t or don’t want to take hormones–some 30 to 50 percent–have other treatment avenues.

Later in 1996, FDA approved the first non-hormonal treatment for osteoporosis. Alendronate, marketed as Fosamax, falls within a class of drugs called bisphosphonates, which hinder bone breakdown remodeling sites by inhibiting osteoclast activity. In clinical trials lasting three years, Fosamax increased the bone mass as much as 8 percent and reduced fractures as much as 30 to 40 percent, depending on skeletal site.

Other drugs recently approved for the prevention and treatment of osteoporosis are Actonel (risedronate), a bisphosphonate similar to Fosamax, and Evista (raloxifene), a drug in a class known as selective estrogen receptor modulators, or SERMs. Both drugs have been shown to reduce the risk of fracture of the spine.

Fluoride, known for fighting dental cavities, stimulates bone building, but studies in osteoporosis patients found the structure of the new bone was abnormal and weaker than normal bone.

Drugs Not Enough

Calcium and vitamin D supplements are an integral part of all treatments for osteoporosis. At the same time, people who take supplements should keep in mind it is possible to consume excess amounts of these and other nutrients. Attention to diet and exercise are important not only for treatment, but also for prevention.

Calcium intake is critical, and those who need it most–younger women and girls–may not get enough. But calcium alone can’t build bones. Vitamin D is needed to help the body absorb calcium. Most people appear to get enough vitamin D because the skin produces it in sunlight, and from foods such as fortified milk products and breakfast cereals. But older adults and people with little exposure to sunlight may need a vitamin D supplement.

A lifelong habit of weight-bearing exercise, such as walking or biking, also helps build and maintain strong bone. The greatest benefit for older people is that physical fitness reduces the risk of fracture, because better balance, muscle strength, and agility make falls less likely. Exercise also provides many other life-enhancing psychological and cardiovascular benefits.

“The truth is, you don’t have to do very much to get most of the benefits of exercise,” Recker says. He suggests 30 minutes of brisk walking five days a week. Add a little weight lifting, and that’s even better. It’s always smart to ask your doctor before starting a new exercise program, especially if you already have osteoporosis or other health problems.

Brighter Horizons

According to Eric Coleman, M.D., of the FDA’s division of metabolic and endocrine drug products, the ability of a hormone called parathyroid hormone or PTH to stimulate formation of new bone is currently being studied. This drug may eventually provide physicians and patients with an important new treatment option.

The study of risk factors also continues. “We consider that to be the research that has the greatest public health significance,” says Sherry Sherman, Ph.D., of the National Institute on Aging. The institute has begun the Study of Women’s Health Across the Nation, a large-scale national examination of the health of women in their 40s and 50s. Researchers expect to learn a great deal about the factors affecting women’s health during these transitional years and beyond. Studies of genetics, biochemical markers, and life habits are already turning up new insights.

Reducing Your Risk

Osteoporosis has been described as a geriatric disease with an adolescent onset, highlighting the importance of beginning to take steps–in exercise and diet–early in life to reduce its disabling impact in later years.

Even though you can’t change your genes, you can still lower your risk with attention to certain lifestyle changes that will help build and maintain bone mass. The younger you start, and the longer you keep it up, the better. Here’s what you can do for yourself:

  • Be sure you get enough calcium and vitamin D.
  • Engage in regular physical activity, such as walking.
  • Don’t smoke.
  • If you drink alcohol, do so in moderation.

A sedentary lifestyle, smoking, excessive drinking, and low calcium intake all increase risk. Although coffee has been suspected as a risk factor, studies so far are inconclusive.

Calcium Counts

Your skeletal calcium bank has to last through old age. Frequent deposits to this retirement account should begin in youth and be maintained throughout life to help minimize withdrawals. Recommendations for daily calcium intakes were established a few years ago by the Institute of Medicine.

Nutritionists recommend meeting your calcium needs with foods naturally rich in calcium. Adequate calcium intake in childhood and young adulthood is critical to achieving peak adult bone mass, yet many adolescent girls replace milk with nutrient-poor beverages like soda pop. “Bone health requires a lot of nutrients and you’re likely to get most of them in dairy products,” says Connie Weaver, Ph.D., who heads the department of food and nutrition at Purdue University, Indiana. People who have trouble digesting milk can look for products treated to reduce lactose. A serving of milk or yogurt contains about 350 milligrams (mg) of calcium. Fortified products have even more.

“People who don’t consume dairy foods can meet their calcium needs with foods that are fortified with calcium, such as orange juice, or with calcium supplements,” says Mona S. Calvo, Ph.D., a calcium expert in the FDA’s Center for Food Safety and Applied Nutrition. Other good sources of calcium are dark-green leafy vegetables like kale and turnip greens, tofu (if made with calcium), canned fish, and fortified cereal products.

The food label can help you identify foods that are a good source of calcium and other nutrients important for bone health, such as vitamin D. You can use the Nutrition Facts found on the label to see if a food is a good source of these nutrients, that is, if it has at least 10 percent of the Daily Value (DV) per serving. Also, if a food has at least 10 percent of the DV, the label may bear a claim it is a good source of a nutrient. If it has 20 percent or more, the label can say it is “high” in or an “excellent source.” Some foods that are excellent sources of calcium may also bear a health claim about the role of diet and other factors in reducing the risk of osteoporosis.

What about too much calcium? A few years ago, the Institute of Medicine established a level of 2,500 milligrams as an upper intake level for calcium for most people. While intakes considerably above this level may be safe for many people, others may be particularly susceptible to calcium’s potentially harmful effects at these higher levels. Those with higher sensitivities, such as people at risk of kidney stones, should discuss calcium with their doctors. And the risks of getting more than this upper level may be greater than a decade ago because the American food supply includes more calcium-fortified foods. (Source: allaboutbackpain.com; HealthNational Institute of Medicine, Washington D.C.)

How Much Calcium Do You Need?

Recommended Intake
1-3 500 mg
4-8 800 mg
9-18 1,300 mg
19-50 1,000 mg
51+ 1,200 mg

To learn more, contact:

  • National Osteoporosis Foundation, 1232 22nd St., N.W., Washington, DC 20037; 1-800-223-9994; www.nof.org.
  • Osteoporosis and Related Bone Diseases National Resource Center (ORBD-NRC); 1-800-624-2663
  • North American Menopause Society, P.O. Box 94527, Cleveland, OH 44101; 1-800-774-5342; www.menopause.org.

10 Tips for Less Stress on the Spine

Bending, reaching, lifting. We do it every day. Yet for some, these routine stresses on the spine can trigger a serious injury. Strengthening your spine is your best course of action to hedge against injuries. Here are 10 simple guidelines to keep your back in good shape:

  1. Standing – Keeping one foot forward of the other, with knees slightly bent, takes the pressure off your low back.
  2. Sitting – Sitting with your knees slightly higher than your hips provides good low back support.
  3. Reaching – Stand on a stool to reach things above your shoulder level.
  4. Moving Heavy Items – Pushing is easier on your back than pulling. Use your arms and legs to start the push. If you must lift a heavy item, get someone to help you.
  5. Lifting – Kneel down on one knee with the other foot flat on the floor, as near as possible to the item you are lifting. Lift with your legs, not your back, keeping the object close to your body at all times.
  6. Carrying – Carrying two small objects (one in either hand) may be easier to handle than one large one. If you must carry one large object, keep it close to your body.
  7. Sleeping – Sleeping on your back puts 55 lbs. of pressure on your back. Putting a couple of pillows under your knees cuts the pressure in half. Lying on your side with a pillow between your knees also reduces the pressure.
  8. Weight Control – Additional weight puts a strain on your back. Keep within 10 lbs. of your ideal weight for a healthier back.
  9. Quit Smoking – Smokers are more prone to back pain than nonsmokers because nicotine restricts the flow of blood to the discs that cushion your vertebrae.
  10. Minor Back Pain – Treat minor back pain with anti-inflammatories and gentle stretching, followed by an ice pack.
    SOURCE: North American Spine Society