Yes, for a while. A cortisone shot in the knee can calm a flare of knee arthritis and ease pain for a few weeks, sometimes longer. Major US guidelines still support it for SHORT-TERM relief.
It doesn’t slow the arthritis or rebuild cartilage. And regular shots are a different story. In a two-year trial, shots every three months led to slightly more cartilage thinning than salt water, and people’s pain was no better.
So the best use is an occasional shot to get you through a bad patch, paired with exercise. Not a standing appointment every few months.
What the shot does in an arthritic knee
- Calms the joint lining: in a flare, the lining of the knee gets irritated and makes extra fluid. The steroid settles this down
- Eases swelling and pain: often noticeable within a few days to a week
- Buys time: relief tends to last a few weeks. Some people get longer, some get little. See how long a cortisone shot lasts
- Doesn’t change the arthritis: the worn cartilage and bone changes stay the same
Knees with a lot of swelling or a clear flare often respond best. A knee that aches steadily without much swelling may get less from it.
What about repeated shots?
This is the question most people want answered. The clearest test came from a trial of 140 people with knee arthritis and an irritated joint lining. Half had a steroid shot every three months for two years. The other half had salt water on the same schedule.
- Cartilage: the steroid group lost about TWICE as much cartilage thickness on scans. The amounts were small, fractions of a millimeter
- Pain: no better than salt water over the two years
- What it means: a shot every three months, long term, doesn’t look like a good deal for most people
One trial doesn’t settle everything, and it didn’t look at the odd shot for a flare. Doctors still disagree on how much the cartilage finding matters in daily life. But it’s a good reason not to lean on regular shots as your main treatment.
A shot for a flare is reasonable. A shot on a schedule is worth questioning.
What guidelines say
- US orthopedic surgeons: say steroid shots can give short-term relief in knee arthritis
- US rheumatologists: recommend them for knee and hip arthritis, in their latest guidance
- Both put exercise first: strengthening and staying active are recommended for everyone with knee arthritis. The shot is an add-on
- The usual limit: at least three months between shots and no more than about three a year. Your doctor may advise fewer
What to do after a knee shot
- Take it easy for a day or two: normal walking around the house is fine. Skip long walks and sport
- Expect a possible flare: the knee can ache more for a day or two before it settles. Ice helps. See cortisone shot side effects
- Start strengthening within the first week or two: sit-to-stands, step-ups, mini squats. The thigh muscles are the knee’s shock absorber
- Build up walking gradually: the pain is quieter, but the knee hasn’t changed. Add a little each week
- Work on the basics: if you carry extra weight, losing some takes real load off the knee. See knee arthritis
If you’re heading toward knee replacement
- Tell your surgeon about any recent knee shot. Many surgeons want a gap of a few months between a shot and the operation, to lower the risk of infection
- Don’t book a shot just before a surgery date without checking first
- If shots stop working and pain is limiting your life despite exercise, that’s a fair time to talk about surgery. See partial knee replacement
Call your doctor today if
- The knee gets hotter, redder and more swollen after the first two days
- You have a fever or chills, or feel unwell
- You suddenly can’t bend or put weight on the knee
- Your calf becomes swollen, warm or painful
Get it checked if
- The shot made no difference after two weeks
- Each shot is lasting less time than the one before
- You’re being offered shots more often than every three months
- The knee locks, catches or keeps giving way
Use the shot to get through a flare, and use your thigh muscles to get through the years.