What
are viscosupplement injections?
Hyaluronic
acid is a natural component of synovial fluid that lubricates joints. Hyaluronan injections are mostly used in osteoarthritis
when the smooth, highly polished surfaces of the joint have become roughened, but there is not any significant inflammation.
What
preparations are available?
There are
many, for example: Hyalgan, Synvisc, Arthrease, Durolane, Fermathron, Orthovisc, Ostenil
and Suplasyn.
Which
of these will be used in my case?
This decision
will be made by your doctor. They differ in their thickness, some components and cost. Different viscosupplements may be suited
to specific joints.
Why
have I been chosen for this treatment?
The articulating
surfaces within your joint have become roughened by disease and are therefore painful when you move. An injection to lubricate
the joint should reduce friction and pain. However, if the damage to the joint has occurred as a result of an inflammatory
disease such as rheumatoid arthritis it makes sense to treat the cause of the problem first. Sometimes the roughening of osteoarthritis
is accompanied by episodes of inflammation. In this case, hyaluronan injection would not be a first choice.
Will
hyaluronan injections stop my osteoarthritis progressing?
Although
there are claims that this is the case, current evidence suggests these injections can give relief from symptoms for variable
duration of time, but not to ‘cure’ or stop the disease..
Which
joints can be injected?
Theoretically,
any affected joint could benefit from treatment. However, some joints are easier to inject than others. The knee joint is
most frequently injected. Some doctors also inject other joints of comparable size such as the shoulder, elbow or ankle. Injection
into the hip joint is technically more difficult, although this may be achieved using ultrasound or xray (in your local X-Ray
Department) to ensure that the needle is inserted in the correct place.
How many injections of hyaluronan
will I need?
This varies,
according to your needs and the specific agent being used. A course of between three and five injections is often suggested,
each separated by between 1–3 weeks, but this will be decided by your doctor.
How
long will the injections last?
If effective
they should work within days. The duration of effect is variable. Sometimes repeat courses will be recommended.
Do
these injections really stay localised in the joint?
When a drug consisting of very small particles
is injected into one knee joint it can be identified in the opposite (non-injected) knee joint only 15 minutes later. The
particles in hyaluronan are quite large, however, so hyaluronan will stay in the joint much
longer before it is absorbed into the blood and transported to the liver for safe destruction. Some of the hyaluronan preparations
available contain significantly larger particles than others and there is some evidence that for these the effects of a single
injection last longer. This may also influence the choice made by your doctor.
Do I need to rest after the injections?
With some injections, such as steroids, it
has been suggested that resting for a few hours after the injection improves the benefit by around 10%. With hyaluronan, resting
after the injection is probably not necessary. However, if your joints are painful enough to require injection you are unlikely
to want to exercise them strenuously.
What are the possible risks or side-effects?
There are very few risks or side-effects.
There is sometimes a slight allergic reaction in the joint causing temporary pain and swelling after the injection. As in
the case of any injection into a joint, there is a remote risk that an infection will be introduced. There is no risk of damage
to the skin or muscle if the injection is slightly misplaced.
Will the hyaluronan injections interfere
with any other drugs I am taking?
There are no known interactions with any drugs.
Will I need any special checks while
having hyaluronan injections?
No.
