Back-to-School Backpacks

Backpacks have become the most popular means for school age children to carry their books and school supplies.  And in fact, when used correctly, a properly designed backpack is an excellent way to carry the necessities of the school day.  Unfortunately, thousands of children each year experience back pain related to use of school backpacks that are too heavy or used incorrectly.  It appears that public awareness of backpack related back injuries has helped to reduce its incidence.  With the start of the new school year, however, it is worth offering a reminder to parents and children of ways to prevent these from occurring.

Choose the right backpack - Be sure that the backpack is the appropriate size for the child. A well-designed backpack will include wide, padded straps to reduce strain on the shoulders and spine.  A chest (sternum) strap and waist belt will help distribute the load over the entire trunk.  Some of the best ergonomically designed backpacks are made by companies that specialize in equipment for hiking (Jan Sport, Osprey, North Face, etc.).  Additionally, salespersons in outdoor specialty shops can be helpful in making sure that the backpack fits appropriately.  Straps that compress the contents of the backpack will stabilize the load and keep it closer to the back.  If carrying heavy loads is unavoidable, a convertible backpack with wheels may be a consideration.  Reflective material to enhance visibility is an important safety feature for children who walk at dusk or after dark.

Wear the backpack properly - A proper fitting backpack rests evenly in the middle of the back, rather than hanging below the level of the lower back or waist.  Both shoulder straps should be used rather than just one.  Shifting the weight of the backpack to one side by using only one strap alters back symmetry, which can lead to neck and back strain.  This advice also applies to backpacks that are designed with only one strap that crosses the front of the body.  When walking a significant distant, encourage your children to use the chest and sternum strap.

Avoid overloading - Most experts recommend that children carry no more than 15% of their body weight in their packs.  For a 50 pound child, this would mean that the backpack and its contents should not weigh more than 7.5 pounds.  This amount would double to 15 pounds for a 100 pound child.  One way of gauging this is to weigh the child with and without the backpack on the bathroom scales.  More weight than this can cause compression of the discs that serve as cushions between the bones of the spine and cause excessive curvature of the spine.  Studies have shown that the amount of back pain reported by children increases along with the load in the backpack.  Parents can help to reduce the weight in their child's backpack by seeing that only those items needed for the school day are packed.  Unnecessary books or items (cell phones, music devices, video games, etc.) should be left at home.

Consider alternatives -  Whenever possible, children should use lockers or their desks during the school day to minimize the load carried in the backpack during the school day.  If there is an option, purchase paperback, rather than hard-bound books in order to decrease the weight of the books that are being carried.  Only those textbooks that are needed for completing homework should be brought home in the backpack.  If unavoidable due to the number or weight of required textbooks, a second set could be purchased for use at home.

Back pain in children should not be ignored.  Since backpack-related back pain is so common, however, parents should consider this as a possible explanation for their child's problem.  A few of the symptoms or signs that could indicate that a backpack may be responsible for the child's pain include:

•  Back pain that is present when wearing a backpack but goes away when removed.
  
•  Excessive back curvature or alteration of posture when wearing a backpack
  
•  Numbness or tingling affecting the arms or legs
  
• Struggling due to excessive weight when putting on or removing the backpack.

Following the recommendations for proper use of the backpack will, in many cases, take care of the problem.  Back pain in children deserves medical attention if it persists despite these measures, inhibits normal activities, requires regular medication, or affects sleep habits.

Avoiding West Nile Virus Disease

Over the past decade, the incidence of West Nile virus disease (WNV) was highest in 2006 when 4269 cases were reported with 177 deaths attributed to this illness.  This year, a total of 693 cases of WNV have been reported to the Centers for Disease Control (CDC), resulting in 26 deaths.  While these numbers are lower than in 2006, it's important to know that the number of cases of WNV reported so far this year is the highest reported through the second week of August.  Almost certainly, we can expect to see more infections and deaths from this potentially preventable disease.  Let's take a closer look at this  illness and measures that can protect you and your family.

How do humans contract this illness?  Most often, WNV is spread by the bite of a mosquito that has fed on an infected bird.  Over 300 species of birds have been found to be infected with the West Nile virus including common songbirds, crows, blackbirds, bluejays, doves, and pigeons.  Once a bird becomes infected, a mosquito can then transfer the virus from the bird's blood stream to humans, setting the stage for the infection.  In a very small number of cases, WNV also has been spread through blood transfusions, organ transplants, breastfeeding and even during pregnancy from mother to baby.

What Are the Symptoms of WNV?  Four out of five individuals who are infected with WNV will have no symptoms at all.  Twenty percent of those infected will develop West Nile Fever which is characterized by mild fever, headache, and body aches, nausea, vomiting, swollen lymph glands and/or a skin rash on the chest, stomach and back.  Less than 1% of those infected will develop a serious form of the disease associated with inflammation of the brain and spinal cord.  This is known as West Nile Encephalitis or West Nile Meningitis.  Symptoms of these include severe headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis.

How is WNV Infection Treated?  As with most viral illnesses, there is no specific treatment available for WNV infection.  Fortunately, most people recover from the illness in a few days to weeks without complications.  In the more serious cases, hospitalization is usually required for supportive treatment such as intravenous fluids and assistance with breathing.  In these individuals long-term problems may develop such as seizures, memory loss, personality changes, paralysis, tremors, and walking or balance problems. As previously noted, in a small percentage of cases, the infection can be fatal.

What can be done to Prevent WNV?  There is no vaccine available to prevent WNV.  Simply stated, the best way to prevent WNV is to avoid mosquito bites.  This does not mean that you or your family should not go outside for the entire summer, but that you should consider taking the following precautions to avoid being bitten by mosquitoes:

• When outdoors, use an insect repellent that contains an EPA-approved active ingredient such as DEET, Picaridin, IR3535, and Oil of Lemon Eucalyptus.
  
• Since mosquitoes are most active at dusk and dawn, along with using a repellent, consider wearing long sleeves and pants during these times.
  
• Be sure that your window and door screens are intact.
  
• Remove sources of standing water around the home that serve as mosquito breeding sites.

Are insect repellants safe to use?  DEET and Picaridin are considered to be "conventional repellents", derived from chemical sources.  Oil of Lemon Eucalyptus (PMD) and IR3535 (e.g. Avon Skin-So-Soft with IR3535) come from natural materials and are classified by the EPA as "biopesticide repellents".  Any of these products will provide safe and effective protection against mosquito bites when used according to labeled instructions.  The EPA has provided the following instruction when using insect repellents:

• Follow the label directions to ensure proper use.
  
• Repellents should be applied only to exposed skin and/or clothing. Do not use under clothing.
  
• Store insect repellents safely out of the reach of children.
  
• Do not apply near eyes and mouth, and apply sparingly around ears.
  
• When using sprays, do not spray directly into face; spray on hands first and then apply to face.
  
• Never use repellents over cuts, wounds, or irritated skin.
  
• Do not spray in enclosed areas. Avoid breathing a spray product, and do not use it near food.
  
• When using on children, apply to your own hands and then put it on the child.
  
• After returning indoors, wash treated skin and clothes with soap and water.

The CDC reports that as of this week, 43 states have seen WNV in people, birds, or mosquitoes.  Most of the infections affecting humans have occurred in three states---Texas, Mississippi, and Oklahoma.  Since the incidence of WNV peaks in late August and September, we appear to be on pace for a record year.  By taking the measures described above, the risk of being bitten by mosquitoes and exposed to the West Nile can be significantly reduced.

"Stuff That Works" - Effective Home Remedies

Taking a cue from a Guy Clark song in which he sings the praises of practical possessions, such as his "ol' blue shirt" and his "used car", today's Health Tip focuses on simple, yet effective home remedies.


Honey for children's cough. Treatment options for symptomatic relief of a cough associated with colds are fairly limited.  In particular, the American Academy of Pediatrics has taken the position that "over-the-counter cough and cold medicines do not work for children younger than 6 years and in some cases may pose a health risk."  Recently, researchers in Israel found that giving two teaspoons of honey before bedtime relieved coughing better than a placebo.  While they did not compare treatment with honey to a cough medication, considering its safety and acceptability, honey is a reasonable first line choice for cold-related coughing in children.  Because of the slight risk of botulism poisoning, honey should not be given to children under the age of one.

Licorice (or liquorice) for cold sores.  Cold sores are caused by the herpes virus and typically resolve on their own after a week or so. Treatment is usually directed at relieving pain or with shortening the length of the outbreak with antiviral medications (Valtrex, Zovirax, etc.).  Licorice contains a compound called glycyrrhizin (or glycyrrhizic acid) which has been used historically to treat several viral infections including colds, flu, and hepatitis.  While chewing licorice will not cure cold sores, it may help speed up their resolution.  Like most medications, licorice can have toxic side effects, particularly if consumed in excess.  These side effects include hypertension and water retention. Licorice is not related to anise or fennel, which have a similar flavor but not the antiviral properties of licorice from the root of the Glycrrhiza plant.

Duct tape for Warts. In The Adventures of Tom Sawyer, Tom proposes to Huck Finn that an effective treatment for warts involves placing a hand in a hollow stump full of water at mid-night and saying 'Barley-corn, barley-corn, injun-meal shorts, Spunk-water, spunk-water, swaller these warts.'  While this seems fairly far-fetched, some of the remedies with scientific backing are similarly exotic.  One of these involves the use of duct tape placed on top of the wart.  The results of studies evaluating this method have been mixed, but there is some evidence to support its use.  Unfortunately, occlusion with duct tape is reported to take several weeks.  More conventional self-care measures involve the use of OTC salicylic acid formulas (Compound W, Occlusal, etc.) and a non-prescription freezing method (Dr. Scholl's Freeze Away).

Zinc for the common cold.  Many people are aware that the mineral zinc is beneficial in the treatment of colds.  When looking at studies evaluating its effectiveness, the strength of this benefit is surprisingly strong.  The Cochrane Foundation reviewed 15 randomized controlled trials, involving 1360 participants and concluded that, when taken within 24 hours of onset of symptoms, zinc (lozenges or syrup) reduced the duration and severity of the common cold in healthy people.  It was also determined from these studies that people taking zinc were less likely to have persistence of their cold symptoms beyond seven days of treatment.  Use of zinc intranasal preparations is not recommended due to the potential for irreversible loss of smell.  A second popular herbal remedy, Echinacea, was not shown to reduce the number of colds that adults catch.

Coffee for Asthma.  Asthma is a serious and sometimes even life-threatening disease. By no means should any "home remedy" be the first line treatment when a number of more effective medications are available.  Nevertheless, there is some evidence to indicate that caffeine, an active ingredient in coffee, tea, and cola drinks may have a beneficial effect by helping to open airways in people with asthma.  Caffeine is chemically similar to the asthma medication, theophylline, which had been a standard treatment for asthma.  Several studies have shown that the amount of caffeine in a cup of coffee can produce improvement in airway function that can last up to a couple of hours.  The 2nd National Health and Nutrition Examination Survey (NHANES II) sought to compare coffee consumption with the presence of asthma and wheezing symptoms in a representative sample of American adults.  Subjects who drank coffee on a regular basis were almost a third less likely to report asthma symptoms as compared to non-coffee drinkers.

Watch for more "Stuff that Works" in future Health Tips!

What an electrocardiogram can (and can't) tell you - Part 2: limitations of the EKG

Last week's Health Tip discussed the usefulness of the EKG, a highly important test used in the diagnosis and management of heart disease.  Like most clinical tests, however, the EKG is not perfect.  Some of the ways in which the EKG falls short in evaluating heart conditions include:

• Evaluating intermittent problems.  Most of us know how difficult it can be to have a problem that comes and goes affecting an automobile "diagnosed" by a mechanic.  The same can be true with an intermittent problem affecting the heart, such as palpitations.  Unless the person with the irregular heart beat is  experiencing symptoms or signs of the condition at the time that the EKG is being performed, it will most likely appear normal.
• Evaluating heart problems that occur only with activity.  The EKG looks at the electrical activity of the heart only in a resting or "static" state.  Underlying heart problems may not be reflected unless the heart is beating rapidly or is under stress as when exercising.  An example of this is someone with constriction of the arteries that supply oxygen to the heart (coronary artery disease) who experiences chest pain (angina) with activity.  Often, when this person is at rest, his or her EKG will not reflect the underlying heart condition.
• Producing false-positive and false-negative findings.  Sometimes the EKG can be overly sensitive and point toward a heart problem that is not really present.  This is called a "false-positive" finding.  Likewise, an EKG may be entirely normal despite the presence of a serious underlying heart condition.  This is called a false-negative finding and is a likely explanation for the person who has a normal EKG during a routine physical exam and shortly afterwards experiences a serious heart attack.
• Causing non-specific changes on EKG.  Sometimes the lines and waves seen on an EKG are "non-specific", meaning that they may or may not be abnormal.  Some of these findings are known as "normal variants", appearing abnormal but occurring without the presence of heart disease.  Other non-specific changes could be due to a number of conditions without pointing to a specific cause.
• Erroneous diagnosis of heart disease in athletes.  As a result of superb conditioning and physiologic adaptation to exercise, athletes may have EKG "abnormalities" that pose no health risk.  A slow heart rate (sometimes as low as 40 beats/minute), enlargement of the heart similar to that seen in long-standing hypertension, and changes in electrical activity (ST segment elevation, inverted T-waves, etc.) suggesting heart stress are some of the most common of these findings.

How can these limitations of the EKG be overcome?  When the EKG findings and the patient's physical condition are at odds, a more in-depth examination, and often other heart tests, may be required to sort things out.  The following are some of the most common of these tests:

• Ambulatory electrocardiography.  In this test, also known as a 24-hr EKG or Holter monitor, a 24 hour recording of the EKG is made while you are going about your normal activities.  It is particularly valuable in someone who has an intermittent problem, such as palpitations.  Also, some heart problems are only present during activity which an ambulatory electrocardiogram will help document.
• Echocardiography. The echocardiogram uses sound waves to scan the heart's muscle and valves that control the flow of blood through and out of the heart.  It even allows doctors to see the heart while it is beating.  The echocardiogram is especially valuable in and in assessing abnormal heart sounds heard during examination, evaluating an enlarged heart, and in helping clear athletes with questionable EKG changes.
• Exercise electrocardiography.  This test is also known as a "treadmill EKG" or "stress test".  During this test the EKG is monitored while the person is walking on a motor-powered treadmill or pedaling a stationary bicycle.  Exercise often provides the additional stress on the heart required to bring out EKG evidence of coronary artery disease.

On occasion even more invasive testing such as a coronary artery catheterization may be required to confirm or rule out a problem noted on EKG.  This is part of the reason that the US Preventive Services Task Force has advised against doctors performing "screening" EKGs on people at low risk of having heart disease.  In "normal" individuals, the EKG is unlikely to predict a heart attack or uncover an undiagnosed heart problem, and because of false-positives and non-specific findings may lead to unnecessary testing.

What an electrocardiogram can (and can't) tell you - Part 1: how and why it's done

The electrocardiogram, also called an EKG or ECG, is a test that records electrical activity within the heart.  With each heartbeat, an electrical signal is conducted through specialized nerves from the upper to lower chambers of the heart.  This causes the heart muscle to contract in a synchronized manner and pump blood throughout the body.  These electrical signals are detected by an EKG machine (electrocardiograph) and recorded as a series of squiggles, lines, and waves that correspond to various events associated with the heartbeat.

When should an EKG be performed?  Some of the reasons that your doctor might recommend that you undergo EKG testing include:

• Unexplained chest pain suggestive of coronary artery disease.
  
• Palpitations or irregular heartbeat
  
• Abnormal heart sounds heard during an examination
  
• Symptoms suggestive of a heart problem, such as shortness of breath, dizziness, or fainting.
  
• Screening for heart problems when multiple risk factors, such as hypertension, high cholesterol, cigarette smoking, diabetes, or a family history of early heart disease are present.
  

How is an EKG performed?  Performing an EKG generally takes around 10 to 15 minutes and is a painless procedure.  Before conducting the test, sticky patches called electrodes are placed on the skin of the chest, arms, and legs.  The electrodes are connected via wires to an EKG machine and allow the EKG machine to study the heart's electrical activity from several different perspectives at the same time.  While lying at rest, a recording is made on paper and/or saved to a computer by the electrocardiograph.

What does the EKG tell the doctor?  The EKG is a highly useful test when performed for the appropriate reasons, such as those described above. Some of the most important findings noted from EKGs include:

1. The presence of coronary artery disease
   
   
2. Heart attacks that are in progress or that have occurred in the past.
   
   
3. Irregularities of normal heart rhythm, such as atrial fibrillation, "extra" heartbeats (e.g. premature ventricular contractions), and heartbeats that are being blocked
   
   
4. Heart enlargement that may have come about from congenital heart disease (e.g. hypertrophic cardiomyopathy), long-standing hypertension or from a viral infection
   
   
5. Inflammation of the sac that surrounds the heart (pericarditis), usually stemming from a viral infection
   
   
6. Abnormalities in the way that electrical impulses travel through the heart (e.g. bundle branch block, long QT syndrome, etc.).
   
   

Since its invention the EKG has been a highly important tool in diagnosing and treating heart disease.  Willem Einthoven, credited with inventing the modern EKG machine, was awarded the Nobel Prize in Medicine in 1924 for his discovery.  As with other tests used in medicine, however, the EKG is not perfect.  There are some significant limitations to its usefulness that will be considered in next week's Health tip.