Injections for Hip and Knee Arthritis: What are the options?

Injections for Hip and Knee Arthritis: What Are the Options?

For patients with hip or knee arthritis, injections can sometimes help decrease pain and improve function without surgery. However, not all injections work the same way, and no injection has been proven to reliably reverse advanced arthritis or regrow normal cartilage.

Here are three of the most common options.

Cortisone Injections

Corticosteroid, or cortisone, injections are commonly used to reduce pain and inflammation from arthritis. Steroids block the inflammation pathway associated with arthritis. Relief can occur relatively quickly, although how long it lasts varies from patient to patient. They can be done up to every 90 days, if necessary, as using them more frequently increases risk of infection. 

Cortisone can be particularly useful for an arthritis flare or for patients who are trying to manage their symptoms without surgery. Repeated injections should be considered thoughtfully, especially in patients who may be approaching joint replacement.

The American Academy of Orthopedic Surgeons (AAOS) give steroid injections “Moderate” recommendation for their use in both hip and knee arthritis.

Hyaluronic Acid (“Gel”) Injections

Hyaluronic acid injections—often called gel injections—are primarily used for knee arthritis. They are intended to improve joint symptoms and may provide temporary pain relief for some patients. Hyaluronic acid is a naturally occurring substance in the body and helps make up the fluid lining of any joint. The purpose of the injection is to provide lubrication to the joint and ease pain from the cartilage loss. 

Results are variable. Some patients notice meaningful improvement, while others experience little benefit. Gel injections are generally not routinely used for advanced hip arthritis.

For knee arthritis, the AAOS at this time does not support their “routine” use at this time with “moderate” level of evidence. For hip arthritis they are actually recommended against their use with "strong" level of evidence.

Platelet-Rich Plasma (PRP)

PRP injections use a concentrated preparation made from a patient’s own blood. A sample of blood is taken from the patient, then a centrifuge is used to spin down the blood to identify the plasma layer. This layer has anti-inflammatory cells and properties. This is then injected back into the patient’s body. Research suggests that PRP may improve pain and function in some patients with knee osteoarthritis, particularly with mild to moderate disease.

However, PRP should not be viewed as a cure for arthritis. Current evidence does not demonstrate that PRP reliably regrows normal cartilage or reverses advanced osteoarthritis. PRP is also not covered by insurance and is an out of pocket expense ranging from 350-1,000$+. 

The AAOS gives it “limited” recommendation for treatment in arthritis. 

Which Injection Is Right for Me?

There is no single injection that is best for every patient. The studies and guidelines show that cortisone has the best evidence for its success based on large scale studies with thousands of patients. The other two injections simply do not have good research to back them despite what some marketing promotions may claim.

Injections are also only one part of arthritis treatment. Exercise, weight management when appropriate, medications, physical therapy, and activity modification can all play important roles.

For patients with advanced arthritis whose symptoms continue despite non-surgical treatment, it may be appropriate to discuss whether hip or knee replacement is the next step.

The goal is to understand all of your options and choose a treatment plan based on your symptoms, lifestyle, and individual needs.