Hyluronate Injections
What is Hyluronate?
It is a solution of a substance called sodium hyaluronate (hyaluronic acid). Hyaluronic acid is a large molecule that is part of the articular cartilage (the structure that covers the bone in a joint).
How do these injections work?
There are some theories as to why the injections may be of benefit. The simplest explanation is that these big molecules act as a lubricant, like oil on a rusty hinge. The next theory is that the injected hyaluronic acid helps to create a more normal environment inside the knee. This environment helps to protect the cartilage and calm the pain receptors in the knee thereby reducing pain.
What are the complications associated with these injections?
- Injection site pain.
- Local skin rash, bruising, and/or itching.
- Allergic reaction.
- Infection. (This can occur with any injection and does not occur any more likely with hyaluronic acid injections.)
Who might benefit from these injections?
- Osteoarthritis (OA) of the knee.
- OA of the knee which has failed to improve with conservative treatment; such as Tylenol, activity modifications, exercise, and weight loss.
- Pain for a long period of time. (If the pain has only been present a short period of time, a steroid injection may be of more benefit.)
Are there reasons the injections can’t be given?
- Allergic to hyaluronic acid.
- Infection in the knee.
- Skin disease over the knee.
- Must be over the age of 18 years old.
How are the injections given?
The Hyluronate is given 1 injection a week for 3 weeks.
What can you realistically expect from these injections?
The studies thus far have shown some benefit from these injections. The best studies have documented that about 50-60 % of patients will obtain some reduction in their pain and increase in their function. The maximal benefit is usually seen about a month after the last injection and may last for a while (not forever). Overall, the number of patients getting relief with these injections is similar to the number getting relief from naprosyn (NSAID). There are fewer complications with the injection versus naprosyn. Unfortunately, at this time there is no way to tell in advance who is going to benefit.
What is the cost of the injections and does insurance cover the costs?
The cost of the injectable medicine is expensive. There is also the cost of giving the injections. Some insurance companies cover these injections and others don’t. The best thing to do is contact your insurance carrier directly. If we decide to do the injections, we will pre-certify you for the injections prior to starting. This may take 1-2 weeks.
Written by James A. Shapiro, MD