Can viscosupplements alleviate arthritic knee pain? Eugene Lotter

There are more than 100 kinds of arthritis, but the three most
common kinds are osteoarthritis, rheumatoid arthritis and
psoriatic arthritis.
Osteoarthritis is often referred to as “wear and tear” arthritis
and affects a large part of the population. It happens as people
grow older, but can also be caused by overweight/obesity or
joint injuries.
No cure for osteoarthritis
Weight-bearing joints like the hips, feet, spine and knees are
the areas that are most affected by osteoarthritis.
According to the American National Institutes of Health (NIH)
osteoarthritis mostly affects cartilage. Cartilage is the slippery
tissue that covers the ends of bones in a joint, allowing bones
to glide over each other. In osteoarthritis, the top layer of
cartilage wears away, which causes bones under the cartilage
to rub together.
This rubbing motion can cause symptoms like pain, swelling,
tenderness, stiffness, loss of flexibility, “grating” and bone
spurs.
Apart from joint replacement surgery there is no cure for
osteoarthritis, but a lot can be done to alleviate symptoms and
prevent the situation from becoming worse. Some ways to
relieve the pain of osteoarthritis and improve mobility are:
- Exercise
- Weight loss
- Anti-inflammatory medication
- Pain relievers
- Steroid injections
- Corticosteroid injections
- Hyaluronic acid injections/viscosupplementation
- Alternative medicine
- Physical devices
- Physical therapy
Hyaluronic acid injections
When nothing else has worked, many doctors are willing to
give hyaluronic acid injections a try before turning to surgery
(knee replacement), especially if the patient can’t take
painkillers like ibuprofen and paracetamol. The side effects are
mild, recovery time is short, and there is a lot of anecdotal
evidence for the effectiveness of viscosupplementation.
Hyaluronic acid is a natural substance in the synovial fluid
surrounding joints where it lubricates bones, enabling them to
move smoothly over each other. Osteoarthritis sufferers have
less hyaluronic acid in their joints than other people and the
idea is that injecting hyaluronic acid into the affected joint will
provide relief from arthritic symptoms.
According to SANOFI , to prepare your knee for injection your
doctor may:
- Clean your knee with alcohol and/or iodine
- Apply a local anaesthetic to your knee
- Insert a needle into your joint
- Withdraw any excess fluid from your joint
- Inject the viscosupplement into your knee joint (intra-articular
injection)
The procedure only takes a few minutes and you can go home
directly afterwards. At home the patient is advised to rest and
to avoid putting strain on the knee. Any pain may be alleviated
with an ice pack. Side effects are usually mild and temporary.
Sanofi says that for people with osteoarthritis of the knee relief
has been shown to last up to a year with three
viscosupplement injections. Success varies from person to
person and repeat treatment is safe and effective.
Hyaluronic acid is often made from rooster combs, and
patients who are allergic to chicken products should avoid
viscosupplements from avian sources.
'Minimal or nonexistent benefit'
Viscosupplementation is widely used for symptomatic knee
osteoarthritis to improve biomechanical function, and the FDA
approved it in 1997.
Although popular, the therapy is controversial, and Anne W.S.
Rutjes, PhD, with the Institute of Social and Preventive
Medicine, at the University of Bern, in Bern, Switzerland, and
colleagues reported their findings regarding the practice online
June 12, 2012 in the Annals of Internal Medicine .
The conclusion of the authors’ meta-analysis was: “The benefit
of viscosupplementation on pain and function in patients with
symptomatic osteoarthritis of the knee is minimal or
nonexistent." They also found that the procedure increased the
risk for “serious adverse events”.
The American Academy of Orthopaedic Surgeons (AAOS) also
recently stated in their guidelines for the treatment of
osteoarthritis of the knee that they cannot recommend using
hyaluronic acid (HA) for patients with symptomatic
osteoarthritis of the knee. (This is bad news for companies
like SANOFI that sell hyaluronic acid [HA].)
Health24 asked Cape Town rheumatologist Dr David Gottlieb
about the use of viscosupplementation for osteoarthritis. He
replied via email that he has no strong belief in the therapy and
doesn’t “think it works any better than a cheap cortisone
injection” and doesn’t use it anymore.
For some it works
There are however influential organisations that strongly
advocate the use of viscosupplementation.
An article by the American Arthritis Foundation gives what is
probably the best assessment of the situation, stating that the
weight of evidence suggests that a (hyaluronic acid) shot in
the knee may bring some osteoarthritis patients relief. And
although studies of viscosupplementation have yielded some
disappointing results, many doctors who treat osteoarthritis
say that, in their clinical experience, hyaluronic acid can
produce significant relief for some patients.
Arthritis Research UK also sends out a generally positive
message: “Hyaluronan injections are most useful in
osteoarthritis when the smooth, highly polished surfaces of the
joint have become roughened but there’s no significant
inflammation.”
Cost of viscosupplementation
According to The Journal of Family Practice the cost of one
hyaluronic acid (30 mg/mL) injection is approximately $230. If
you receive a course of three to five weekly knee injections,
your total cost per treatment could be more than $1 000 per
knee. This is a lot of money and the benefit of
viscosupplementation must be carefully compared with other
therapies.
- Health24