or OA, is the most common joint disease affecting middle-age and older
people. It is characterized by progressive damage to the joint
cartilage - the cushioning material at the end of long bones - and causes
changes in the structures around the joint.
People with knee osteoarthritis need to adopt a physically active lifestyle, or at least a goal of 6,000
steps a day, to get major health benefits. Yet most people with knee osteoarthritis often have difficulty with physical
function, such as getting out of a chair and walking, which limits the
ability to be physically active.
‘Most people with knee osteoarthritis already have the physical function necessary to walk at least 6,000 steps a day, the minimum amount needed to improve their arthritis and prevent disability.’
According to new research findings
presented this week at the 2016 ACR/ARHP Annual Meeting in Washington,
most people with knee OA actually already have the physical function
necessary to walk at least 6,000 steps a day, the minimum amount needed
to improve their arthritis and prevent disability.
Researchers at the University of
Delaware's Department of Physical Therapy analyzed publicly available
data from the Osteoarthritis Initiative to measure physical activity and
physical function among OA patients.
"We were interested in
understanding what minimal level of functional ability was necessary to
be physically active," said Daniel K. White, Assistant
Professor and the study's lead author. "For instance, how far does one
need to be able to walk in order to be active in the community?"
minimum physical function thresholds a day helps clinicians prioritize
when to prescribe interventions like physical therapy. Physical function
was measured according to timed, five-repetition sit-to-stand (STS)
tests, timed 400-meter walks, and walking speed on a 20-meter walk. To
establish a minimum threshold for both physical function and activity,
they calculated cut points at 80% and 95% specificity for
walking 6,000 steps per day.
There were 1,790 participants who
wore their monitors for three or more days and moved 6,319 ± 2,920 steps
a day, with 47% walking more than 6,000 steps a day. The mean
STS test results for these participants was 10.2 ± 3.2 seconds, and
their 400-meter walk speed was 305.3 ± 51.4 seconds. Their walking speed
was 1.3 ± 0.2 meters per second. Physical function at or below these
thresholds may be a barrier to people with OA getting the minimum level
of physical activity they need, said White.
The good news is that
most people with knee OA already meet these physical function
thresholds. For those patients who are below these thresholds,
interventions that target improvement of physical function may help them
achieve the target of 6,000 steps a day, he said.
are important to both patients and providers. They are important to
patients to realize that most people with knee OA are able to live a
physically active lifestyle. They are important to providers to
understand when someone may need help with their functional ability to
become physically active, such as receiving a referral for physical
therapy," he said.
In the future, White hopes to utilize this
research and conduct even more studies to promote physical activity to
people with knee OA.
"Now that we have an idea of how much
ability is necessary to be active, we can better develop intervention
strategies that are personalized to patients' individualized needs so we
can get them to be more active," he said.