Multiple
studies are finding that people having knee replacements continue to gain
weight after surgery.
(Oseoarthr. Cartil. 2010 Apr;
18(4):510-4; Orthopedics 2005 Feb; 28(2): 157-9; Scott Med J 2009 Feb;
54(1):26-8)
So
why are they gaining weight?
Is
it exercise or other lifestyle factors?
In a 2010 study published in Osteoarthritis
and Cartilage, one hundred and six adults with unilateral, end-stage knee
osteoarthritis (OA) and thirty-one persons without knee pain participated in
the prospective longitudinal study. Subjects with OA underwent primary
unilateral total knee replacement and received post-operative out-patient
physical therapy. Height, weight, quadriceps strength and self-perceived
functional ability were measured at baseline and at a 2-year follow-up.
Body Mass Index (BMI)
showed a significant increase in the surgical group, but not in the control
group.
67% of the surgical group
gained an average of 14 lbs (despite decreased pain and improved function).
The weight gains after surgery cannot be attributed to age
alone. The high BMI of the surgical
group should be treated as independent of their OA.
I often
hear from patients that they have gained weight because their knee hurts and
they can't exercise. Studies such as the
one above show they have reduced pain and increased function after
surgery. The patient-described barrier
to weight loss is now gone. There must
be reasons other than a lack of activity for continued weight gain…and it’s not
the total knee
surgery!
Barriers
to weight loss
Sedentary lifestyle. Knee pain was just a good excuse…maybe they
never did much physical activity anyway?
Other medical conditions-
diabetes, hypothyroidism, and other disorders that effect metabolism often
cause weight gain.
Medications-
some prescription medications can directly or indirectly promote weight gain.
Sleep-
inadequate sleep can cause release of stress hormones that can cause weight
gain.
Diet- most
important to weight management is your diet.
Too many calories get stored as fat.
The
studies suggest that patients should not look at their painful knee as the
cause of their weight gain. Prospective
surgical patients should pursue lifestyle modifications prior to surgery that
will promote improved health, including weight loss.
Start lifestyle
changes prior to surgery
·
Set
weight loss goals.
Not just weight, but also take some body measurements such as your
waist. Men should try to have a waist
measurement that is less than 40 inches.
This isn't your pant size, but actually tape measurement at the level of
your belly-button.
·
Increase
physical activity...make it a habit. I realize that your knees may hurt with
walking, so try to pursue lower impact activities such as pool based exercises
and biking. Perform resistance exercises
for your upper body to build muscle. You
would also be surprised that performing resistance exercises for your legs may
also help with your pain.
·
Sleep
eight hours per night.
Sleep is very important for your body to recover and repair from the
day's activities.
·
Discuss
medications with your physician. Medications can directly and indirectly
affect your weight. If you are taking a
number of medications, ask your physician how they may be affecting your
weight. If you are diabetic, your medications
are sensitive to activity level and diet, so please consult with your physician
when making lifestyle changes.
·
Diet. I feel the most important lifestyle
modification is diet. Below are some
recommendations I have found beneficial:
- Avoid processed foods and sugar.
- Cut back on starchy carbohydrates (this included bread and pasta). It is too easy to overindulge in starchy, processed carbs.
- Your best carbohydrate sources are vegetables followed by fruit such as berries. Veggies and fruits are good choices due to their high nutrient density and fiber content.
- Eat a hardy breakfast. Eggs are good for you!
To
answer the question, “Do total knee replacements make you fat?” the answer is, “NO.” However, a total knee replacement alone will
not help you lose weight.
What
has been your experience with weight loss or gain after a total knee
replacement?



