Introduction

Zilretta is a US Food and Drug Administration (FDA) approved injectable suspension used to manage osteoarthritis pain in the knee joint. It is the first and only FDA-approved treatment for this condition to use extended-release microsphere technology. These microspheres are tiny particles that contain a medicine called triamcinolone acetonide, which helps reduce inflammation and pain. Once injected directly into the knee, the microspheres slowly release the medicine for about three months.

Indications

Zilretta is for treating osteoarthritic knee pain that has not responded to traditional conservative treatments such as anti-inflammatory medications, physical therapy, or other types of injections.

Procedure and Post-procedure Care

During the procedure, the patient is seated or lying down, and the skin over the injection site is sterilized and numbed with a local anesthetic. A needle is inserted into the joint, and the medication is injected. In some cases, a small amount of joint fluid is withdrawn before the medication is administered. After the procedure, you will be observed for a few hours. You may be able to fully bear weight after a couple of hours, but crutches may be needed temporarily. It is common to experience pain, swelling, or discomfort, which can be managed with over-the-counter medications and ice packs. Strenuous activities should be avoided for a couple of days.

Risks and Complications Some potential side effects include allergic reactions, sore throat, runny nose, bruising, headache, back pain, and pain and swelling in the joint.