Cortisone Shots for Hip & Knee Arthritis: How Often and How Long They Last

When an arthritic hip or knee flares up, a cortisone shot is often the fastest way to calm it down. I use it regularly, for the right patient at the right time. I think of it as a way to buy time, not as a cure.

What a cortisone shot does

Cortisone is a corticosteroid, a strong anti-inflammatory. Placed into the hip or knee, it calms the inflammation that drives much of the pain and swelling of arthritis. Many people notice relief within a few days.

Some people have a day or two of extra soreness before the shot kicks in. If you have diabetes, your blood sugar may run higher for a few days.

How long does a cortisone shot last?

Three to six months on average, but the range is wide. Some people get more than a year. Some get only a few weeks. I talk about it as a bell curve rather than a single number, because the average hides how much people differ. The same person can also respond differently over time as the arthritis changes.

How often can you get a cortisone shot?

I won't repeat a shot in the same joint within 3 months. After that, it can be repeated as needed, for as long as it keeps helping.

You may have heard that you're limited to three a year. There is no fixed limit. Very frequent steroid shots aren't good for a joint over the long run, which is why we space them out, not because of a number on a chart.

Cortisone shots in the hip

In the hip, there are two different injections, and the right one depends on where it hurts and what your X-rays show:

I never do both at the same visit, so we can tell which one helped. For more, see hip injections: the joint or the bursa?

Cortisone shots in the knee

In the knee, the shot goes into the joint. It's one of three injection options for knee arthritis, along with gel and PRP. Which one I recommend depends on where you are with your arthritis. A knee that keeps swelling from arthritis often settles with a cortisone shot.

When the shots stop lasting

There's no set number of years you can keep getting cortisone. What usually changes is that the shots stop lasting as long. The shot that gave you six good months two years ago may give you six weeks now.

That isn't the injection failing. It's a sign the arthritis has progressed. If you need shots closer and closer together, it's time to talk about what's next, especially if the hip or knee is affecting your sleep, your walking or the things you enjoy. See signs you may need a knee replacement and the signs for the hip.

Cortisone and surgery

If a replacement is in your future, timing matters. I wait at least 3 months after a shot before replacing that same joint, because a shot close to surgery raises the risk of infection. If you're seriously considering surgery, think ahead before scheduling another shot. More on that in cortisone injections before joint replacement.

Cortisone vs. gel and PRP

• Cortisone: fast relief of inflammation, hip or knee, generally covered by insurance.
• Gel (hyaluronic acid): knee only.
• PRP: your own platelets, for the hip or knee. Not covered by insurance.

For a side-by-side comparison, see injection options compared. All of them are part of the broader non-surgical treatment plan.

Are cortisone shots covered by insurance?

Generally, yes. Cortisone injections are a long-established part of arthritis care and are typically covered, unlike PRP. Coverage details vary by plan, so it's worth confirming with your insurer.