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MAYO CLINIC HEALTH LETTER
Reliable Information for a Healthier Life
VOLUME 30 NUMBER 11 NOVEMBER 2012
Inside this issue
Avoiding knee pain
HEALTH TIPS . . . . . . . . . . . . . . . . . 3
Vision for the future.
NEWS AND OUR VIEWS . . . . . 4
High demand likely for prescription weight-control drugs.
COSMETIC SURGERY . . . . . . . . . 4
Common options for older adults.
DENTURE CARE
A daily task.
Meniscus tears
. . . . . . . . . . . . . .
6
OSTEOPOROSIS DRUGS . . . . . . 7
Current and future options.
SECOND OPINION . . . . . . . . . . . 8
Coming in December
You probably know what it’s like to
open products with safety lids — press
down, twist and turn. While that may
work for opening lids, those same types
of motions made in relationship to your
knee joint can cause trouble.
Maneuvers that forcefully compress
and twist or rotate the knee can potentially lead to a torn meniscus, which is
cartilage in the knee joint. This cartilage acts like a cushion between the
shinbone (tibia) and thighbone (femur).
Meniscal tears are among the most
common knee injuries. How torn knee
cartilage is treated varies considerably.
For older adults, treatment decisions
can be more complex if osteoarthritis
also is present in the affected knee.
Inside matter
Within the normal knee joint are
two C-shaped menisci. The job of each
meniscus is to:
■ Help absorb and distribute weight
and force that’s placed on the knee
■ Provide stability to the knee when
pivoting
■ Lubricate the knee joint
In addition, the menisci help protect
other cartilage tissue that covers the
ends of the joint’s tibia and femur bones.
Damage to the menisci may be sudden and severe, as can happen to athletes in competitive contact sports, such
as football. The classic dodge maneuver — where you abruptly stop running
and change directions — is a common
way menisci can tear. Other common
moves, such as kneeling and squatting,
also can cause damage.
On the flip side, tears may go unnoticed, developing over time from
RHEUMATOID ARTHRITIS
Aggressive treatment can halt the
disease.
ISCHEMIC COLITIS
Reduced blood flow to the colon.
TONGUE PROBLEMS
Basic remedies usually help.
PERIPHERAL EDEMA
Causes of swollen legs vary.
Meniscal tears are among the most common knee injuries.
regular joint wear that occurs naturally.
Among older adults, wearing down of
the meniscus is part of degenerative
arthritis that may affect the rest of the
aging knee. These changes in the meniscus are best called wear and tear,
since they often don’t result from an
injury and may have no symptoms.
Pain from an actual meniscus injury can vary. The signs and symptoms
of a meniscal tear may include:
■ A popping sensation when moving
the knee
■ Swelling or stiffness
■ Pain, especially when twisting or
rotating your knee
■ Possible difficulty straightening your
knee fully
Sorting it out
If you have knee pain or swelling
of the joint — whether unexplained or
due to injury — or you find you can’t
move your knee normally, contact your
doctor. Along with a clinical history,
you’ll be asked about any signs or symptoms related to your knee. As part of the
physical examination, your doctor may
manipulate your knee into different positions in order to put stress on the internal structures, such as the meniscus.
A torn meniscus that causes pain
can often be identified during a physical exam. However, if you also have
degenerative changes in the joint related to osteoarthritis, determining
what might be the actual cause of the
knee pain or malfunction can be more
challenging. Both the meniscus and
arthritis can cause pain.
Imaging studies may include X-rays
done in special standing positions,
which can show some changes that
might be related to osteoarthritis. If
there are no major findings on X-rays
suggesting significant arthritis and the
physical examination indicates you
may have a meniscus tear, magnetic
resonance imaging (MRI) will likely be
done to get a clearer picture of the meniscus and the rest of the knee joint.
But MRI scans are best done only
when there are significant symptoms.
2
www.HealthLetter.MayoClinic.com
In the absence of symptoms, MRI scans
could lead to costly and ineffective
treatment. MRI images are so sensitive
that they can pick up abnormalities in
the knees that are causing no noticeable pain. One study of 991 adults between the ages of 50 and 90 with no
knee pain found that half of them had
meniscal wear-and-tear changes that
could be seen on an MRI scan. This
means that not all abnormal-looking
menisci on MRI scan cause pain.
Treatment options
Whenever possible, nonoperative
conservative measures are generally
considered the first line of treatment
when there are symptoms of meniscal
problems. This approach involves resting your knee by avoiding activities that
put pressure on the joint or twist it and
cause pain, such as squatting, kneeling
and repetitive bending of your knee.
Along with rest, ice can help reduce
pain and swelling. Keep your leg elevated while icing the knee for about 15
minutes every four to six hours for a
day or two. A nonprescription pain reliever also may help ease knee pain.
Once pain is diminished, the next
step is typically physical therapy to
strengthen the muscles around your
knee and in your legs. Research has
shown that improving muscle support
around the knee helps to reduce the
pain of knee wear-and-tear problems.
Physical therapy is supplemented by
home exercises, as well. In addition,
an injection of cortisone into the knee
may help relieve inflammation and
pain. This can make the therapy and
exercise treatment more effective. If
after several months of conservative
treatment your knee remains painful,
your doctor may recommend surgery.
Arthroscopic knee surgery for a
meniscal tear that’s causing symptoms
is a common orthopedic procedure
that’s done through tiny incisions
around your knee. The arthroscope
contains a small camera and light that
allow your surgeon to clearly view the
inside of your knee on a monitor. Small
November 2012
surgical tools can be inserted through
the arthroscope or through additional
tiny incisions to remove portions of or
repair meniscal cartilage. You can usually go home the same day, although
full recovery may take weeks or months.
As part of your recovery, you’ll be
taught exercises designed to help
restore motion and strengthen the

muscles of your knee and leg.
However, if osteoarthritis also is
present in the affected knee and the
meniscal problem is due to wear and
tear, surgical treatment may not provide
the kind of pain relief or return to better
joint function normally expected with
arthroscopic surgery. Several studies
involving people with meniscal tears
and advanced osteoarthritis have demonstrated that arthroscopy — including
the prescribed post-surgical physical
therapy — offers no advantage over
MAYO CLINIC HEALTH LETTER
Managing Editor
Aleta Capelle
Medical Editor
Robert Sheeler, M.D.
Associate Editors
Carol Gunderson
Joey Keillor
Associate Medical Editor
Amindra Arora, M.B.,
B.Chir.
Medical Illustration
Michael King
Editorial Research
Deirdre Herman
Customer Service Manager
Ann Allen
Proofreading
Miranda Attlesey
Donna Hanson
Julie Maas
Administrative Assistant
Beverly Steele
EDITORIAL BOARD
Shreyasee Amin, M.D., Rheumatology; Amindra
Arora, M.B., B.Chir., Gastroenterology and Hepatology;
Brent Bauer, M.D., Internal Medicine; Julie Bjoraker,
M.D., Internal Medicine; Lisa Buss Preszler, Pharm.D.,
Pharmacy; Bart Clarke, M.D., Endocrinology and
Metabolism; William Cliby, M.D., Gynecologic
Surgery; Clayton Cowl, M.D., Pulmonary and Critical
Care; Mark Davis, M.D., Dermatology; Michael
Halasy, P.A.-C., Emergency Medicine; Timothy
Moynihan, M.D., Oncology; Suzanne Norby, M.D.,
Nephrology; Norman Rasmussen, Ed.D., Psychology;
Daniel Roberts, M.D., Hospital Internal Medicine;
Robert Sheeler, M.D., Family Medicine; Phillip
Sheridan, D.D.S., Periodontics; Peter Southorn, M.D.,
Anesthesiology; Ronald Swee, M.D., Radiology;
Farris Timimi, M.D., Cardiology; Matthew Tollefson,
M.D., Urology; Debra Zillmer, M.D., Orthopedics;
Aleta Capelle, Health Information. Ex officio: Carol
Gunderson, Joey Keillor.
Mayo Clinic Health Letter (ISSN 0741-6245) is
published monthly by Mayo Foundation for Medical
Education and Research, a subsidiary of Mayo
Foundation, 200 First St. SW, Rochester, MN 55905.
Subscription price is $29.55 a year, which includes a
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nonoperative treatment including physical therapy for relief of symptoms.
Even so, considerable research gaps
still exist in this area, in particular for
those who have meniscal tears and less
advanced osteoarthritis.
Filling the gap
At present, a large, multicenter
study is under way to compare the effectiveness of arthroscopic surgery to
nonoperative treatment — physical
therapy and joint injections — in people who have both mild to moderate
osteoarthritis and meniscal tears. The
Meniscal Tear With Osteoarthritis
esearch (MeTeOR) study involves
R
seven medical centers, including Mayo
Clinic. Recruitment for this large-scale
clinical trial ended in August 2011, and
people were randomly assigned to either the surgical treatment group or the
physical therapy group. Each participant will be followed for five years with
physical exams, radiology images,
questionnaires and phone surveys.
Orthopedic surgeons involved with
MeTeOR hope the study outcomes can
help clarify treatment choices, especially among older adults who often
have knee osteoarthritis along with a
meniscal tear. ❒
Give knees a leg up
Take a few minutes each day to help give your knees the support they need. These
simple exercises are designed to strengthen the large muscles in your upper leg
that play a key role in stabilizing and supporting your knees. Before doing these,
warm up for five minutes or so with a low-impact activity, such as walking:
■ Straight-leg lift — Lie on your back as shown. Relax your upper body while
tightening your stomach muscles so that your low back is flat against the floor.
Tighten the thigh muscles in your straight leg and slowly lift it with a smooth motion
until it’s about a foot off the floor. Hold it for three to five seconds — remember not
to arch your back. Then slowly lower your leg to the floor. Repeat and switch sides.
Wall squat — Stand as shown with
your head, back and hips against the
wall. Step your feet out about two feet
from the wall keeping your feet about
hip-width apart. Tighten your stomach
muscles and slowly slide down the wall
until you are in a high sitting position
— don’t let your knees move forward
over your toes. Hold for five to 10 seconds, then slowly slide up. Repeat. As
you get stronger, you may hold the
position longer.
■
November 2012
Health tips
Vision for the future
Some age-related vision changes
are inevitable, but there are steps
you can take to care for your future eye health, including:
■ Wearing sunglasses — Make
a habit of wearing sunglasses that
block 99 to 100 percent of ultraviolet A and B radiation.
■ Wearing protective eyewear
— When working with power
tools or using chemicals such as
household cleaners and garden
chemicals, wear protective safety
glasses or goggles.
■ Eating for eye health — Eat
plenty of green leafy vegetables
and chose fatty fish, such as salmon. These foods are rich in the
carotenoids lutein and zeaxanthin. Certain antioxidants and
omega-3 fatty acids have been
shown to lower risk of cataracts
and macular degeneration.
■ Scheduling regular eye exams
— Chronic eye disorders, such as
macular degeneration, glaucoma
and diabetic retinopathy, can
cause serious eye damage before
you’re aware of them. Regular,
comprehensive eye exams —
which include dilating the eye to
get a good look at the back of the
eye — can detect eye problems
at their earliest stage. Generally,
if you’re older than 65, exams are
suggested every one to two years.
However, your eye care provider
may recommend more-frequent
exams based on your family history and your personal health —
such as if you have diabetes.
■ Stopping smoking — If you
smoke, stop. Smoking is linked to
increased risk of age-related macular degeneration, cataracts and
optic nerve damage. ❒
3
News and our views
High demand likely for prescription weight-control drugs
Recent approval by the Food and Drug Administration (FDA) of two weightcontrol drugs is fueling renewed interest in medication-based weight loss.
More than one-third of Americans are considered obese — which is defined
as having a body mass index (BMI) of 30 or greater — and more than twothirds are overweight with a BMI between 25 and 30.
If trends persist, the obesity rate is expected to approach 50 percent over
the next two decades. Adding to the concern, obesity is a significant risk
factor for developing other medical conditions — notably diabetes, high
blood pressure, high cholesterol and heart disease.
Doctors generally promote diet and exercise recommendations as key
components to address weight loss. But medical professionals also acknowledge results can be mixed, and most people regain much of the lost weight.
Until these drugs, medication options geared toward weight loss have
been limited. The new prescription drugs — lorcaserin (Belviq) and a combination drug consisting of phentermine and topiramate (Qsymia) — are the
first weight-control drugs in 13 years to receive FDA approval.
Qsymia combines two medications that were previously approved for
other uses. Phentermine is approved for short-term use for weight loss, and
topiramate is approved for preventing migraines and managing seizures.
The combination drug uses lower doses of each. When used in addition to
diet and exercise, Qsymia has produced average weight loss of 6.7 to 8.9
percent over one year, depending on the dose.
Belviq works by activating a serotonin receptor in the brain that regulates
hunger. In clinical trials, it has been associated with an average weight loss
of up to 3.7 percent more than those taking a placebo.
The new drugs are approved for adults with a BMI of 30 or greater, and
for adults who have a BMI of 27 or greater — and have at least one other
weight-related condition, such as high blood pressure or diabetes. Each of
the new medications has been approved for long-term use in conjunction
with a reduced-calorie diet and exercise for chronic weight management.
Among the side effects that may occur while taking Belviq are headache,
dizziness, fatigue and nausea. Those who have diabetes and take Belviq
may experience low blood sugar. With Qsymia, some of the common side
effects include tingling of the hands and feet, dizziness, altered taste sensation and insomnia, but more-serious side effects — including kidney stones
and a type of acute glaucoma — are possible. Qsymia can’t be used if you
have glaucoma or hyperthyroidism and should be avoided if you have had
recent heart disease or stroke.
Mayo Clinic doctors are cautiously optimistic about the two drugs. Despite the need for medications that target obesity, many of the drugs that
have been approved in the past — specifically dexfenfluramine, fenfluramine
and sibutramine — had significant adverse effects requiring them to be pulled
from the market. Because of this, Mayo Clinic doctors recommend working
closely with your doctor or with a doctor who has expertise in weight loss
if you’re considering using these recently approved drugs.
Qsymia may be available soon and Belviq may be available in early
2013. The consumer price for each has not yet been announced. ❒
4
November 2012
Cosmetic
surgery
Common options
for older adults
Most older adults are under no illusion
that they can reverse time and be young
again, but it’s not uncommon for them
to toy with the idea of cosmetic surgery
to improve what they’ve got.
In 2011, about 350,000 adults older
than 55 had some type of cosmetic
surgery. This number is expected to

climb as the population ages. Moreover,
many older adults are hitting the golden
years in good health and full of energy.
Cosmetic surgery may be a way to help
some people look as young as they feel.
However, cosmetic surgery can have
its downsides. You’ll want to consider
your motivations and expectations, the
risks and discomfort of surgery, and the
expense of the procedure and any complications — which isn’t likely to be
covered by a typical insurance plan.
Going into it
Cosmetic surgery is still surgery.
Even if everything goes perfectly, you’ll
still undergo some type of local or general anesthesia, and your body will
need to rally a healing response to cutting and manipulation of tissues. Bruising may take a few weeks to go away,
and swelling may last up to six weeks.
It may take up to six months before the
final results are apparent, and scars may
take longer to improve in appearance.
Good overall health is important.
Healthy older adults have no greater rate
of complications with a face-lift than do
younger people. In essence, your health
status is a more important consideration
than your age. Still, there’s always some
risk of major complications such as heart
or lung problems, or of less s erious but
still problematic complications such as
muscle weakness, skin numbness, blood
pooling under the skin or wound-healing problems.
Heart disease, diabetes and many
other medical issues may make cosmetic surgery much riskier than it would
be in a healthy adult. Smoking also is a
barrier to cosmetic surgery, as smoking
impairs skin healing. It’s usually recommended that any weight-loss goals be
achieved prior to surgery, as fluctuating
weight can loosen or stretch skin.
Your attitude and expectations are
also important. If you’re dissatisfied
with your body image and seek c osmetic
surgery as a cure for that d
issatisfaction
— or for other problems in your life
— your expectations aren’t likely to be
met. In contrast, if you are happy with
yourself overall and seek cosmetic
surgery to improve one aspect of your
body in a realistic way, you’re more
likely to be satisfied with results.
The face-lift
Age, heredity, sun exposure, smoking and obesity can all take a toll on
facial skin. Skin may develop deep

wrinkles, fat deposits may develop and
skin may sag, creating tired-looking
eyes or jowls under the jaw.
A traditional face-lift involves incisions that start inside your hairline at
your temples and extend downward in
front of your ears, under the earlobe
and into your lower scalp. A small incision may also be made under your chin
if you desire tightening of the skin on
your neck. Skin is separated away from
the fat and the muscle that lies beneath.
Tummy tucks
A tummy tuck is an extensive cosmetic surgery involving a large
abdominal incision, removal of
excess fat and skin, and repair
and tightening of muscles.
Some adults 65 and older do
undergo this procedure, but the
recovery is typically harder than
the other procedures discussed in
this article, making tummy tucks
less common among older adults.
Fat may be trimmed and suctioned
away, and underlying tissues may be
tightened. Skin is pulled back into
place, the excess is trimmed away, and
the remaining skin is secured into
place. A face-lift can be performed in
conjunction with other facial procedures such as nose reshaping, chin
augmentation, tightening sagging eyelids (blepharoplasty) and a forehead lift.
Initially, your face will look s wollen,
pale and bruised. It often takes four to
six weeks for the face to start looking
normal again, although facial numbness that may occur can take longer to
go away, and incision scars will take
longer to fade. Results are typically long
lasting, and they will last longer if your
weight is maintained and you have a
healthy lifestyle.
Breast surgery
One of the most common cosmetic
surgeries involving the breasts of older
women is the revision of a previous
breast implant. Over time, implants can
deflate or cause other problems that warrant removal or replacement. Older
women sometimes elect to have firsttime breast implants. If that’s something
you’re considering, realize that it’s fairly common to have a revision surgery
to correct a problem within the first 10
years of receiving the implant.
Another common cosmetic surgery
is the breast lift (mastopexy), which
may be done in conjunction with a
November 2012
breast implant revision or a breast-size
reduction procedure.
Breast tissue is held in position by
breast skin. As breast skin stretches due
to age, gravity, pregnancy or weight
fluctuation, the tissue inside sags with
the sagging skin, giving breasts a less
youthful appearance. Depending on the
characteristics of your breast, a breast
lift may involve incisions around only
the darkened area that surrounds the
nipple (areola), or one or two additional incisions below the areola.
Underlying breast tissues are lifted,
the nipple and areola are positioned
higher, and excess skin tissue is r emoved.
Results are often good, although asymmetry can sometimes be an issue. R
esults
are also fairly long lasting, although
aging and fluctuations in weight may
cause additional sagging.
Liposuction
Liposuction is used to remove fat
from isolated areas where it won’t go
away despite weight loss or maintenance of a healthy weight. It involves
one of several procedures in which a
probe is inserted under the skin to dislodge fat cells and suction them out.
After fat removal, the skin molds
itself to the new contours of the treated
areas. If you have good skin tone and
elasticity, the skin is likely to appear
smooth. If your skin is thin with poor
elasticity — as can occur in older adults
— the skin in the treated areas may appear loose. The resulting contour
changes are generally permanent, as
long as your weight remains stable. ❒
5
Denture care
A daily task
You might think of dentures as a durable, no-frills replacement for unhealthy or missing natural teeth. However, dentures are precisely crafted and
relatively delicate items. They require
careful handling to avoid damage and
frequent cleaning to keep bacteria to a
minimum and to keep them free of
stains and looking their best.
In addition, your gums need daily
attention, and regular visits to your dentist are necessary to ensure your dentures fit properly. In many ways, taking
care of dentures is more work than caring for natural teeth.
Careful handling
Dentures can be fragile, so it pays to
be careful when you’re handling them.
The role of adhesives
Denture adhesives can help provide added stability to well-fitting
dentures, but they shouldn’t be
used to secure poorly fitting dentures. Poorly fitting dentures can
lead to mouth sores and other
problems.
Check with your doctor on
how often to use an adhesive.
Excessive use may be associated
with risks, such as getting too
much zinc.
Don’t treat a mouth sore
caused by dentures with a numbing ointment, unless directed by
your dentist. A numbing ointment
may mask a more extensive problem or allow a sore to worsen
without you even realizing it.
Irritation or soreness caused by
dentures — or dentures that aren’t
working as well as they once did
— requires examination by your
dentist and possible adjustment.
6
For example, dentures can break if
dropped only a few inches. When cleaning them, do so over a folded towel so
that if they’re accidentally dropped, they
won’t be damaged. Additional tips for
avoiding denture damage include:
■ Brush or clean gently — Metal
clasps or other denture components
can become bent or damaged if you
clean dentures too aggressively.
■ Soak overnight — Most types of
dentures need to remain moist to keep
their shape. Ask your dentist to recommend a way to store them. Soaking
them in water or a mild denture-soaking solution is usually fine. However,
some solutions can cause problems in
certain types of dentures, such as chlorine solutions causing tarnish on dentures with metal attachments.
If you use a denture-soaking solution, remember to rinse your dentures
before putting them in your mouth, as
some solutions contain potentially
harmful chemicals.
■ Avoid certain cleansing methods
— Stiff-bristled toothbrushes, abrasive
cleansers and harsh toothpastes such as
whitening paste are all abrasive enough
to damage dentures. In addition, soaking
dentures in bleach can cause the pink
part of the denture to whiten, and placing dentures in hot or boiling water can
cause the plastic to warp.
Cleansing the right way
Poor denture care and oral hygiene
are the top causes of problems such as
soreness, irritation and fungal infections. You can keep your dentures and
your mouth clean by:
■ Removing and rinsing dentures after
eating — Even if you don’t brush after
meals, simply running water over your
dentures removes food debris and other particles.
■ Gently scrubbing dentures at least
daily — This helps prevent permanent
stains and prevents buildup of bacteria
and other deposits. Gently scrub your
dentures with a soft-bristled toothbrush
using a denture cleaner, mild soap or
dishwashing liquid.
November 2012
■ Brushing your mouth, too — Brushing your gums, tongue and palate helps
remove bacteria and stimulates blood
flow to these soft tissues. If you have
any remaining teeth, brush and floss
them every day.
Dentist adjustments
Properly functioning dentures require a good fit. But this can be a
moving target. Natural teeth are supported by a specialized type of bone in
the upper and lower jaws. When teeth
are removed or lost, this bone begins to
shrink and the shape of your gums
changes. The rate at which this occurs
varies from person to person, and it can
be accelerated by continuously wearing
dentures, such as wearing them to bed.
When the shape of your gums
changes, loose or poorly fitting dentures may result, leading to irritation or
sores. It may also become a challenge
to talk and eat, and the dentures may
have a tendency to become dislodged.
Whatever kind of dentures you
have, they will need periodic adjustments by your dentist to keep them
comfortable and prevent problems.
Don’t try to do this yourself. Repairs you
try to make probably won’t work, and
you may cause needless mouth
irritation or denture damage. Gluing
cracked dentures with glue from the
hardware store is a particularly bad idea
as it typically contains harsh chemicals
that you don’t want in your mouth.
In addition to minor repair or refitting, your dentures may occasionally
need to be:
■ Relined — This is the resurfacing of
the part of the denture that contacts
your gums.
■ Rebased — If your denture base is
cracked or damaged — or if relining
isn’t enough — you may need a whole
new denture base for the denture teeth.
■ Replaced — Wear and tear often
necessitates replacing dentures every
five to seven years on average.
Proper denture care is the best way
to ensure that your dentures last as long
as possible. ❒
Osteoporosis
drugs
Current and future
options
The bone-thinning disease osteoporosis
is a major health concern in the United
States, affecting 10 million adults — the
vast majority being older women. If you
have osteoporosis, the risk of having a
fracture during your lifetime may be 40
percent or even higher. In addition,
fractures occurring in the hip and spine
result in hospitalization and the risk of
other complications.
Although there’s no cure for osteoporosis, the mainstays of treatment are
weight-bearing exercise and adequate
amounts of calcium and vitamin D,
preferably from a healthy diet. Increasingly, many drugs are being used to
help manage and recalibrate bone
health. Most of the drugs available to
treat osteoporosis are designed to prevent further bone loss that can lead to
potentially devastating fractures. So far,
there’s only one drug approved for use
in the U.S. that actually builds bone,
but researchers hope to increase that
number in the near future.
Osteoclasts, osteoblasts and fractures
Existing bone tissue is continuously
being replaced with new bone tissue
in a process called bone remodeling.
Those developing new drugs to treat
osteoporosis take their cues from recent
progress in understanding the intricacies of bone-cell biology and how bone
remodeling is controlled.
Bone remodeling occurs in two basic steps — bone breakdown (resorption) and bone formation. Each step is
carried out by specialized bone cells
that are regulated by hormones and
other substances in the body.
Resorption is the job of cells called
osteoclasts, which attach themselves to
bone and make use of special enzymes
to break down bone surface. Proteins
and minerals are released into circulating blood as the osteoclasts create microscopic cavities on bone surfaces.
Cells in the bone formation crew —
called osteoblasts — follow. They migrate to these microscopic bone cavities
and fill them in with a protein meshwork
called collagen. Eventually, this meshwork hardens as minerals carried in the
bloodstream — such as calcium and
phosphorus — are deposited in the collagen. The result is a hard, concrete-like
structure that replaces the bone tissue
that was removed by the osteoclasts.
cur with aging. At present, the only
osteoporosis drug that truly builds new
bone is the daily injectable drug teri
paratide (Forteo).
Teriparatide is a form of the human
parathyroid hormone (PTH), and it’s the
first in the bone drug class known as
anabolics. Its use is generally reserved
for severe osteoporosis and limited to
two years. After completion of a course
of teriparatide, treatment with an antiresorptive medication generally is recommended to preserve new bone
formed during the teriparatide therapy.
Current treatments
The balance of bone remodeling
shifts over time. Generally, through
young adulthood, more bone is formed
than is removed. As you age, the rate
of bone breakdown overtakes bone
formation, setting up a slow process of
bone loss. However, that process increases among older adults, and dramatically so for women in the years just
after menopause.
Of the medications approved by the
Food and Drug Administration to treat
osteoporosis, most are anti-resorptive
drugs — they slow bone resorption. Essentially, anti-resorptives slow the process of bone loss by preventing the
development and activity of osteoclast
cells or the activity of osteoclasts.
The majority of anti-resorptives are
in a class of drugs called b
isphosphonates
and include alendronate (Fosamax),
ibandronate (Boniva), risedronate (Actonel) and zoledronic acid (Reclast,
Zometa). Additional anti-resorptive drugs
include raloxifene (Evista), which is a
selective estrogen receptor modulator
(SERM), and the hormone calcitonin
(Fortical, Miacalcin), which is produced in the thyroid gland. The latest
addition to the anti-resorptive drug arsenal is a monoclonal antibody drug
called denosumab (Prolia).
While anti-resorptive drugs play a
key role in managing osteoporosis and
preserving the bone you have, they
don’t restore bone structure lost to the
bone remodeling imbalances that oc-
The anabolic pipeline
Interest in anabolic therapies is considerable because some people, such
as those with severe osteoporosis, may
still experience fractures despite taking
bone-preserving medications like alendronate. In addition, simply maintaining current bone density may not be a
suitable goal for younger or steroidtreated people who’ve already experienced osteoporotic fractures.
As a testament to research efforts,
several of these newer bone-forming
drugs are midway along or through the
multiphase clinical trials. Among the
anabolic drugs under study, the one
that appears nearest to possible approval is anti-sclerostin antibody.
Sclerostin is a protein that plays a
role in regulating cellular activities relevant to bone remodeling. Normally,
sclerostin increases bone breakdown by
putting the brakes on the bone-forming
osteoblast cells. Anti-sclerostin antibody
turns the tables and lets off the brakes,
resulting in new bone formation.
Based on cost, monitoring and how
anabolics are taken — typically by injection — anabolic therapy treatment
is much more intensive than anti-resorptive therapies.
As with teriparatide, future anabolic drugs generally will be reserved
to treat severe osteoporosis. This almost
always means people who have already experienced osteoporotic fractures rather than those who simply have
low bone density scores. ❒
November 2012
7
Second opinion
Q
I saw a celebrity on television
running a marathon on a replaced knee joint. Is it OK to do things
like that on a replaced knee or hip?
A
Surveys of orthopedic surgeons
show that high-impact sports such
as jogging, basketball, football and soccer typically aren’t recommended for
those with a replaced knee or hip joint.
When walking, the force transmitted to the hip joint is about two times
your body weight. During running, the
peak force transmitted to the hip joint
is five times your body weight, and can
be even higher at the knee joint.
The more force that’s applied to an
artificial joint, the more likely it is that
problems may arise, such as breakage,
loosening, instability, or excessive wear
and tear of the implant. Any of these issues could lead to additional surgery.
Further, most people receive a hip
or knee replacement to relieve pain, and
once this goal is achieved, it can be hard
to justify the risk of participating in highimpact activities. Many enjoyable sports
and activities, such as cycling, walking,
dancing, swimming and golf, are allowed without restriction.
It has yet to be proved that jogging
on a knee or hip replacement is reasonably safe, and research has yet to determine the amount of risk you may be
taking if you jog on a replaced joint.
Still, it’s not out of the question for
someone with a background in a sport
such as running to attempt to get back
into the sport on a limited basis after
joint replacement. But in general, marathon-running isn’t recommended after
knee replacement.
Talk to your surgeon about potential
risks before resuming any high-impact
activities. Risks may vary based on the
type of implant you have, or other factors that may lead to wear or mechanical failure of your joint replacement.
There are certainly risks, but if approached with caution, your doctor’s
consent —
and extensive physical therapy to develop hip, knee, back and core
strength — as well as appropriate sportspecific training, it’s possible to continue a very active lifestyle. ❒
Although the 10,000 steps recommendation isn’t specifically part of the
guidelines, counting steps is a way people may choose to meet the guidelines.
The downside is that a pedometer doesn’t
differentiate between casual walking and
moderately intense walking.
If you choose to use step counting
as a way to help you reach your exercise goals, brisk walking that incrementally improves your daily step count is
a great way to improve your capacity
for physical activity. ❒
Q
Correction
I recently purchased a pedometer to see how many steps I
take in a day. Where did the idea of
walking 10,000 steps a day originate?
A
The 10,000 steps a day walking
program originated in Japan in the
1960s. Japanese walking clubs were
increasingly using pedometers made in
Japan. The pedometer’s nickname was
manpo-kei, which literally translated is
“10,000 steps meter.” At the time, it
was roughly assumed that 10,000 daily
steps was a good idea.
In the decades since, 10,000 steps
has become popular advice and an informal marker used by some to gauge
their activity levels from day to day. Current guidelines recommend at least 150
minutes of moderately intense activity
— such as brisk walking — every week
for older adults who are generally fit and
have no limiting health conditions.
Those 150 minutes can be broken up
into half-hour chunks of activity on most
days of the week. Even shorter periods
of moderate activity that last at least 10
minutes count toward the weekly goal.
On page 5 of the September 2012 issue,
we wrongly stated that spinal cord stimulators are a newer use of technology
that hasn’t been approved by the FDA.
Instead, it’s peripheral nerve stimulators
that are a newer use of technology that
hasn’t been approved by the FDA. ❒
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November 2012
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