Intra-articular Knee Injections

Knee pain and stiffness can be disabling and difficult to treat. It can limit an individual’s lifestyle and negatively impact body image and emotional well-being.

An intra-articular knee injection is a very effective form of treatment where medicine is delivered directly into the knee joint with the primary objective of relieving pain from conditions such as arthritis.

Intra-articular knee injections are usually recommended when pain has not responded to traditional conservative treatments such as anti-inflammatory medications, physical therapy, activity modification, or ice therapy.

Types of Intra-Articular Knee Injections

There are various types of intra-articular injections. Depending on your condition, your doctor may recommend an intra-articular injection of:

• Hyaluronic acid is a naturally occurring substance in the joints that provides lubrication and acts as a shock absorber. With arthritis, this substance is largely deficient, leading to worsening of the condition. Hyaluronic acid injections into the knee can help reduce pain and improve range of motion.
• Your doctor may perform an intra-articular injection of corticosteroids to reduce inflammation in the knee joint. Corticosteroids prevent the production of inflammatory cells that are naturally produced in response to an acute injury or arthritic conditions.
• Platelet-rich plasma or PRP is obtained from your blood and may be used in an intra-articular injection of the knee joint to encourage tissue regeneration, reduce pain and improve function.
• Arthrocentesis is a procedure where excess joint fluid is removed with a needle that is inserted into the joint space. It is done to reduce swelling and pain in the knee. Usually after removing the excess joint fluid from the knee, your doctor will use the same puncture site to inject a corticosteroid preparation or anesthetic to further alleviate pain and inflammation.

Indications

Intra-articular knee injections are commonly indicated for knee conditions such as:

• Osteoarthritis
• Rheumatoid arthritis
• Gout

Procedure

Intra-articular knee injections may be performed using various approaches. During the procedure, you will be seated or will lie on your back with the affected knee flexed or extended. The skin over the injection site is sterilized and numbed with a local anesthetic. The needle is inserted into your knee joint and the medication is injected.  In some cases, ultrasound imaging is used to help guide the needle to the correct site. You may feel some mild discomfort during the injection. In some cases, prior to injecting the medicine, a small amount of joint fluid is withdrawn to make space for the medication. Once the fluid is removed, the same site is used to administer the intra-articular injection. A small dressing is then applied over the injection site to complete the procedure.

Postoperative care

Postoperative care will include the following instructions:

• Avoid strenuous activities for a couple of days
• Apply ice on the injection site for comfort
• Rest, elevation, and medicines are recommended to relieve pain and swelling
• Gentle range of motion exercises are recommended

Risks and Complications

Intra-articular knee injections are a relatively safe procedure. However, as with any procedure, there may be certain risks and complications such as:

• Infection at the injection site
• Reaction at the injection site
• Pain or swelling at the injection site
• Septic arthritis
• Acute arthritis
• Inflammation of the joint lining
• Nerve Injury

Summary

Intra-articular knee injections are a safe and effective procedure to treat pain from conditions such as osteoarthritis and rheumatoid arthritis. The procedure only takes a few minutes and can be performed in an in-office clinic setting. Though results vary from person to person, an intra-articular injection can often help you return to your regular activities and avoid surgery.