Injection Options for Knee Osteoarthritis: A Guide to Pain Relief

Knee osteoarthritis (OA) is a common condition that affects millions of people worldwide, causing pain, stiffness, and reduced mobility. While lifestyle changes, physical therapy, and medications can help manage symptoms, many individuals turn to injections for targeted pain relief. If you're considering injection therapy, understanding the different options available can help you make an informed decision.

1. Corticosteroid Injections

Corticosteroid injections are a widely used treatment for knee OA. These injections deliver powerful anti-inflammatory medication directly into the knee joint, reducing pain and swelling. Benefits include:

• Quick relief from pain and inflammation

• Minimal downtime post-injection

• Suitable for short-term relief (effects last from a few weeks to several months)

However, repeated use can lead to cartilage damage and diminished effectiveness over time.

Corticosteroid injections are the only injections currently recommended by the American Academy of Orthopedic Surgeons.

2. Hyaluronic Acid Injections

Also known as viscosupplementation, hyaluronic acid injections aim to improve joint lubrication and reduce friction. This treatment can be beneficial for those with mild to moderate OA. Key advantages include:

• Enhancing joint cushioning and movement

• Potential long-term relief lasting up to six months

• Fewer side effects compared to corticosteroids

Large scale clinical studies have suggested that hyaluronic acid injections do not work as well as we originally hoped. Because of this they are no longer widely recommended and your insurance may choose not to cover them.

3. Platelet-Rich Plasma (PRP) Injections

PRP injections utilize a concentration of the patient’s own platelets to promote healing and reduce inflammation. This regenerative therapy is gaining popularity due to its potential to slow OA progression. Benefits include:

• Stimulating tissue repair and regeneration

• Longer-lasting relief compared to steroids

• A natural, drug-free treatment option

Early clinical studies suggest that PRP may reduce arthritis knee pain. However, studies remain mixed on the overall benefit of PRP for knee osteoarthritis and this option is not currently covered by a majority of insurance plans. The cost for a PRP injection is usually between $750 - $1,000 US dollars per shot.

4. Stem Cell Therapy

Stem cell injections have been suggested to aide in the restoration of articular cartilage. However, this claim has never been shown to be true in actual clinical practice. There is little evidence to suggest stem cells help in knee osteoarthritis and they can often be very expensive. These types of injections are not routinely recommended for the treatment of knee osteoarthritis.

Knee Treatment Research Group Opinion

Corticosteroids remain the first-line treatment for knee osteoarthritis. Cortisone injections are recommended to all patients as first treatment. However, cortisone injections loose effectiveness when repeated, and repeat injections may increase the risk of infection if a patient were to go on to a knee surgery in the future. Given the balance between effectiveness and infection risk most orthopedic surgeons limit corticosteroid injections to only a few (less than four) in any joint.

Viscosupplementation injection (gel) injections have mixed effectiveness. They seem to work well for some patients and not at all for other patients. I do not routinely recommend gel injections, however, I am not against them when they are covered by a patient’s insurance.

PRP and stem cell injections remain in a category that show promise but that I do not routinely recommend. Given their out of pocket cost they remain out of reach for many patients. However, the risk of these injections is overall low, so if patients can afford them they do not pose much risk and may offer some benefit.