Osteoarthritis is a difficult problem to treat. The most definitive solution is of course replacing part or all of the knee. Many of our patients are looking for nonoperative options for their pain related to osteoarthritis prior to undergoing an extensive surgery. The good news is that one more option has become FDA approved to use in osteoarthritic knees.
Zilretta received FDA approval for treatment of osteoarthritis knee pain in late 2017. It slowly gained interest from the orthopedic community and acceptance from insurance payers. We have been using it here at the Grossteam for 2-3 years on select patients and have had good success. To really understand why we use it though, you really have to take a look at how the injection works.
Many people with arthritis will experience at least one steroid injection into their knee. Many have had multiple by the time they reach our office, with varying degrees of pain relief. A traditional corticosteroid injection will provide relief to patients usually over the course of 4-8 weeks. They get the injection, get a strong burst of steroid, and then it's gone. I try to explain this to patients like a mountain, sharp curve up and then right back down the other side.
Zilretta is similar because it contains the same type of steroids we often injection into the knee. (Triamcinolone) It is different in the way this steroid is housed inside the injection. The molecules of steroid are actually surround by a microsphere of PLGA ( Poly Lactic-co-Glycolic Acid) which encapsulates them until release. (See image below) These microspheres settle into the soft tissues of the knee and slowly burst, or release the steroid over time. The studies performed by the manufacture are showing patients getting relief for 4 months after the injection. https://zilretta.com/
Zilretta is one of many nonoperative options for our patients with knee pain. We are happy to discuss this injection with you at your next appointment. As with anything, it is not a perfect fit for everyone, but it is nice to have another treatment choice for our patients with osteoarthritis.