
         ------------------------------------------------------------
                          AGING AND HORMONAL CHANGES 
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       All living things grow old. The spine is not immune to the 
       process and in fact ages more rapidly than other parts of the 
       body. 
       
       One of the trademarks of the aging process is the gradual 
       dessication or drying out of body tissues. It seems odd that a 
       man or woman will live comfortably to an age of 80 yet begin to 
       show signs of spinal aging in the early twenties. However, at 
       that early age it can be demonstrated that the intervertebral 
       discs are starting to lose their flexibility and moisture 
       content. Aging has begun. 
       
       This may be due to our genetic makeup as well as the relentless 
       force of gravity constantly pressing on the unstable upright 
       spinal column. 
       
       The discs, as we learned from an earlier chapter, comprise about 
       25% of the length of the spinal column. As aging takes place 
       they gradually become compressed, lose moisture and shrink. 
       Joint motion, flexibility and all-important shock absorbing 
       qualities gradually diminish. Chronic spinal strain thus begins. 
       
       These mechanical stresses are transferred to the vertebrae, 
       supporting muscles and ligaments. The ligaments holding the 
       structure together may be pulled or lifted from the vertebral 
       surfaces which in turn attempt to minimize the instability by 
       creating bony spurs or growth projections to fill the missing 
       spaces. This can eventually lead to osteoarthritis as the spine 
       shrinks in overall length. A classic and for the most part 
       inescapable fact of aging. 
       
       However if the supporting muscles and structures of the spine 
       are kept in good shape with judicious exercise habits, the pain 
       and loss of flexibility is minimized to a certain extent. In the 
       back and spine, as no other site of the body, the truism "use it 
       or lose it" has clear and absolute meaning. 

       Osteoporosis or osteopoenia can be a side effect of aging. 
       Gradually the bones can become brittle and spongy, thus losing 
       critical bone tissue mass. Normal bone tissue is not a static, 
       dead tissue. It may seem dead and brittle, but it is definitely 
       not dead. A constant turnover of bone calcium and other tissue 
       takes place at all times within bones. One perspective is that 
       every bone in your body is replaced, molecule for molecule, 
       every 6.5 years. 
       
       Bones also react to stress and fractures - healing and bonding 
       together to reproduce the original load bearing characteristics 
       and also enlarging slightly along the axis of stress. Put a bone 
       under pressure and, within limits, it will attempt to grow 
       stronger and deposit additional calcium to counteract the 
       stress. Astronauts in the gravity free environment gradually 
       lose calcium. In a sense gravity is both friend and foe: it 
       provides the stress which keeps bones strong yet it eventually 
       collapses and compresses our upright spinal column. A biological 
       paradox at best. 
       
       Bone has two primary anatomic structures: 1) matrix, the protein 
       "sponge" into which calcium is deposited and hardened. 2) An 
       intercellular tissue which fills the hollow pores of the matrix 
       with solid calcium salts - a sort of glue which binds the tissue 
       and calcium together. 

       The matrix onto which calcium is deposited is produced by 
       osteoblast cells. Meanwhile another variety of cell, the 
       osteoclast, reabsorbs bone which has aged and must be removed. 
       
       Thus two opposing forces are at work governed by different 
       cells: one deposits bone mass, the other removes it. Usually the 
       chemical and cellular forces are in balance. However when the 
       osteoclasts gain the upper hand, more bone is removed than is 
       replaced. This is the mysterious mechanism which is the basis of 
       the disease osteoporosis. 
       
       However we need to go a little further to learn about the 
       specific dynamics of this process and how it affects the spine. 
       
       The outer portion of bone is hard and is called the cortical 
       layer. The inner core is softer and spongy and is known as the 
       cancellous layer. The inner cancellous layer is the region where 
       dynamic chemical and cellular activity takes place. Calcium 
       salts are moved around, primary blood cells are generated and a 
       host of other process occur within this bone core area. 
       
       And this is the central clue why the vertebrae of the spine seem 
       to be uniquely prone to osteoporosis, certain infections and 
       some tumors. It is because a LARGER region of the vertebrae is 
       CANCELLOUS (soft tissue - dynamic cell reactions) than cortical 
       (relatively stable - slow chemical turnover). Because of this 
       important difference, the bones of the spine are much more 
       easily disturbed by chemical, hormonal or metabolic imbalances 
       in other parts of the body. 
       
       In this respect, the structure of the vertebrae of the spine are 
       dramatically different from bones in the other parts of the 
       body. Why do these vertebral bones have this unique structure? 
       Some anthropologists speculate that our own evolution is to 
       blame. Our rapid adoption of an upright posture REQUIRED the 
       bones of the spine to become more cancellous and dynamic in 
       cellular activity to allow for an unstable and inherently risky 
       upright spinal posture. Nature and evolution simply did the best 
       it could given the short time frame needed to adopt an upright 
       posture! 

       A particular hormonal imbalance, usually associated with the 
       menopause of women, has been linked statistically to 
       osteoporosis. Apparently the shifting tides of hormones produced 
       at menopause can lead to gradual thinning and spongy weakening 
       of the vertebral bones whose uniquely dynamic and chemically 
       sensitive cancellous core is susceptible to the hormone 
       triggered event we call osteoporosis. 
       
       X rays conclusively reveal the weakening of the vertebral bodies 
       in osteoporosis. The attempted treatment, although by no means 
       conclusively successful, is hormone replacement therapy. 
       Frequently this means administration of both male (testosterone) 
       and female (estrogen) hormones. Calcium tablets and vitamin D 
       may also be prescribed. The benefit of this method of therapy is 
       open to debate among members of the medical community, although 
       it is usually attempted as the the best available treatment for 
       now. Hip fractures in elderly patients have also been reduced by 
       providing vitamin D and calcium within an enriched dietary plan. 

       In the case of senile osteoporosis, a variation not related to 
       menopause, different hormones are usually administered along 
       with calcium and vitamin D tablets. The results are also not 
       clearly demonstrated, but are nonetheless frequently attempted. 

       Once vertebral collapse occurs, back braces or surgery may be 
       required. Bed rest is not always the treatment to use in this 
       situation because once bed rest or disuse sets in, the spongy 
       vertebrae begin to deteriorate rapidly. Lack of use tends to 
       accelerate the process of bone loss in most conditions involving 
       osteoporosis. Bones need a certain amount of use and exposure to 
       gravity to keep calcium deposits in place. Bed rest can 
       accelerate calcium loss. 

       One malady related to osteoporosis is the gradual expansion of 
       the intervertebral discs into the upper and lower plates - the 
       roof and floor - of the bony vertebrae themselves. However, if 
       the vertebrae have already lost most of their elasticity, this 
       likelihood is diminished. Unlike a disc rupture which takes 
       place either into the spinal canal or outwards towards the 
       lateral side of the spinal column, disc expansion can take place 
       directly into the weakened mass of the vertebral body itself in 
       cases of osteoporosis. 

         ------------------------------------------------------------
                                  INFECTIONS 
         -----------------------------------------------------------
        
       Infections and tumors of the spine are rare indeed, but worth 
       mentioning in any discussion of maladies which affect the spine. 
       
       The advent of modern antibiotics has erradicated many spinal 
       infections, but nonetheless prudent physicians consider and test 
       for the presence of spinal infections when other causes cannot 
       be assigned. 
       
       Tuberculosis is usually associated with a severe infection of 
       the lungs but has been reported in medical literature to also 
       infect the vertebrae of the spinal column. The bacteria which 
       causes tuberculosis is easily carried in the blood stream and 
       can take up residence in the spongy core of the vertebrae. Since 
       the bacteria cause slow growing abscesses and eventual formation 
       of scar tissue, patients may eventually report loss of motor or 
       other nerve function as the spine is compressed or pinched by 
       the encroaching scar tissue and gradually collapsing vertebral 
       bone mass. 
       
       In severe cases of tuberculosis of the spine, partial or 
       complete paralysis of the lower body has been reported if spinal 
       nerves are severely affected. A low grade fever, common with 
       most bacterial infections, is an early manifestation. Profuse 
       sweating at night, back pain, vomiting and a limit in the range 
       of motion of the back may follow. A chest X ray may show no 
       evidence of lung involvement. A biopsy with a hypodermic syringe 
       is the conclusive laboratory test for presence of infection. 
       This procedure removes a small quantity of fluid from a 
       suspected spinal abscess which is sent to a medical laboratory 
       for positive identification of the tuberculosis bacillus. 
       Surgery and spinal fusion is the corrective method of choice in 
       advanced stages of the disease. The bacteria which infects the 
       spine selectively attacks the bone mass of the vertebrae and 
       seldom involves the flexible discs since they do not contain 
       oxygen and blood which the bacteria requires for growth. 

       A serious outbreak of antibiotic-resistant tuberculosis began to 
       surface in early 1992 and was reportedly seen in New York and 
       regions of Florida. Although initial reports suggest it is 
       primarily linked to tuberculosis of the lungs, spinal 
       involvement may evolve as the bacteria spreads into the general 
       population. New antibiotic compounds are currently under 
       investigation to treat this unusually virulent form of 
       tuberculosis which could eventually cause a new pandemic and 
       reversion to earlier methods of treatment such as sanitorium 
       care and strict isolation. 

       Meningitis refers to an infection of the spinal cord. A variety 
       of bacteria and virus organisms have been implicated as causing 
       this serious disease. Symptoms include, but are not limited to, 
       stiffness of the neck and spine and painful spasms. The 
       meningoccocus bacteria, a common cause of meningitis, may also 
       cause fever. However, viral organisms causing meningitis may not 
       always produce fever. The early stages of meningitis may begin 
       as simple back pain. A common diagnostic test is for the 
       physician to test muscle reflexes in the lower extremities. If 
       specific lower body reflex sites are hyperactive (overly 
       reactive to touch), meningitis is a strong suspect. 
       
       Polio, or more properly poliomyelitis, involves similar viral 
       infection of the spinal cord. However, common anti-polio 
       vaccines have almost erradicated this disease in the United 
       States, but it does continue to surface in parts of Africa and 
       remote regions of the World. 

       Spondylitis is a bacterial infection of the spine usually 
       involving the common staphylococcus bacteria which may be 
       carried to the site of the spine by the bloodstream. The 
       vertebral bones are usually infected and the bacteria may spread 
       from one vertebrae to the next. Back pain, fever and loss of 
       appetite may be present in spondylitis victims. X rays of the 
       vertebrae in early stages of the disease may show little 
       evidence of infection, but as the bacteria grow, X rays and 
       biopsy (drawing infected fluid from the vertebra with a 
       hypodermic needle) provide conclusive identification of this 
       bacteria. Antibiotics are usually able to halt the spread of the 
       infection. Surgery may be required if the vertebrae have been 
       severely damaged or contain large abscesses. 

         ------------------------------------------------------------
                                    TUMORS 
         -----------------------------------------------------------

       Discussing tumors immediately brings to mind a sinister word: 
       cancer. 
       
       However it is important to note that cancer applies to malignant 
       or spreading tumors which invade and destroy healthy tissue and 
       bone. Benign tumors generally do not spread throughout the body, 
       can be removed by surgery and may present little actual tissue 
       damage. 

       Thankfully, tumors both benign and malignant of the spine are 
       relatively rare. 

       Malignant tumors are generally divided into two classes: Primary 
       and secondary. Primary tumors originate in a specific tissue or 
       bone. Secondary tumors, also known as metastatic tumors, have 
       spread to a specific tissue from another primary site of origin. 
       
       The most common sites where primary malignant tumors begin are 
       the prostate gland, breast, lung, kidney and thyroid. These are 
       the classic sites where the majority of cancers originate. 
       Primary malignant tumors may eventually involve bone, especially 
       the large bones of the spinal column and lumbar vertebrae 
       because of their spongy, blood rich cancellous core which was 
       discussed earlier. 

       Diagnostic methods to determine the primary or original site of 
       the cancer are frequently undertaken by a physician and may 
       involve tests such as X rays of the lung, thyroid studies with 
       radioactive materials, pyelograms of the kidney, mamograms of 
       the breast, ultrasound studies of the prostate and biopsy of the 
       spine. Treatment may involve a combination of radiation, 
       chemotherapy and hormones which is directed at the primary or 
       original site of cancer growth. Treatment of the secondary site 
       may involve a similar or modified treatment with radiation and 
       chemotherapy as well. 

       Malignant tumors can involve areas other than the bones of the 
       spine. Liposarcomas and fibrosarcomas are malignant tumors of 
       fatty tissues and muscles of the back respectively. Schwannoma 
       is a malignant cancerous invasion of the spinal cord. 

       Malignant tumors of the spine are usually secondary - they have 
       spread to that location from another part of the body. In fact 
       the first sign of cancer in another part of the body, the 
       prostate or kidneys for example, is the presence of back pain 
       which results from the invasion of the cancer to the bones of 
       the spine or soft tissue of the back from its primary site. Some 
       physicians note that if back pain increases when the patient 
       lies down, a tumor may be a probable culprit - although this 
       simple clinical observation must be corroborated with additional 
       tests. 
       
       Other than the secondary tumors we have discussed, a few primary 
       tumors of the spine have also been detailed in medical 
       literature. Several rare types have been reported: 1) Osteogenic 
       sarcoma, a rare and extremely deadly form of cancer which grows 
       rapidly. 2) Multiple myeloma which reflects an abnormal rapid 
       growth of bone marrow cells. 3) Chordoma which is usually slower 
       growing and may confine itself to localized areas of the spine. 
       Chordomas can be surgically removed with moderate success, but 
       can recur with time although their growth and reappearance is 
       slow. Sarcomas are usually fast growing and more resistant to 
       surgery, radiation and chemotherapy - and thus among the 
       deadliest of tumors. 
       
       This tutorial is merely a starting point! For further 
       information on back care and back pain, be sure to register this 
       software ($25.00) which brings by prompt postal delivery a 
       printed, illustrated guide to back pain written by a physician 
       plus two software disks. From the main menu select "Print 
       Registration Form." Or from the DOS prompt type the command  
       ORDER. Mail to Seattle Scientific Photography (Dept. BRN), PO 
       Box 1506, Mercer Island, WA 98040. If you cannot print the order 
       form, send $25.00 to the above address and a short letter 
       requesting these materials. End of chapter. 

