7 Reasons Your Knee Cortisone Shots Keep Wearing Off Faster (And What Australian Seniors Are Doing Instead)

Let's be fair to cortisone. When your knee flares up, a shot can settle it down, and for a lot of people it does exactly that.

Cortisone calms the inflammation inside the joint for a while. That's its job. Australia's GP guideline for knee osteoarthritis says the benefit shown in studies lasts up to about six weeks.

For many people, that means relief measured in weeks, not months.

What a shot doesn't do is look after the knee on all the other days. Your knee cartilage has no direct blood supply of its own. It depends on the circulation in the tissue around it. A shot doesn't change that.

So when the relief runs out, it's the same knee underneath, with a few more months of stairs, low chairs and car doors behind it. No wonder each shot can feel like it runs out sooner.

It was never you. It's the gap between the shots.

Most of what people try between appointments does one thing. A heat pack warms the skin, then goes cold. A brace holds the joint, but does nothing for the tissue around it. A cheap massager buzzes on the surface.

Mendable Knee runs three therapies used in rehabilitation, at the same time, around the whole knee:

Not one therapy. All three, together, in one 12-minute session.

Wrap it around the knee, press start, and all three run together while you sit. It's the kind of support that used to mean a clinic. Now it fits in your lounge room.

It won't replace your GP, your physio or your surgeon. But it gives your knee something on the days between appointments, instead of nothing.

Mendable Knee was designed by Dr. James Anderson, a Sydney orthopaedic surgeon with 22 years in practice.

He isn't against cortisone. He still sees a place for it when a knee flares up badly.

What bothered him was what happened after the shot: people coming back with the same knee, with nothing to do for it in the meantime but tablets and rest.

So he brought together three therapies that are standard in rehabilitation clinics, heat, compression and vibration, into one session you can run at home in 12 minutes, every day.

Tablets dull the pain for a few hours. A heat pack goes cold in minutes. A brace holds the joint while you wear it. Another shot buys a few more weeks.

None of them looks after the knee every day. And repeating the shot raises its own questions.

Australia's GP guideline for knee and hip osteoarthritis (RACGP, 2018) says: "Clinicians need to be cautious of the potential harms of repeated use."

And a study published in 2025 in Radiology, the journal of the Radiological Society of North America, linked a single cortisone injection with more knee joint wear on MRI over the following two years, compared with people who had no injection. It was a small US study, with 44 people given cortisone, and it shows a link, not proof that the injection caused it.

That's not a reason to cancel anything your doctor has planned. It's a reason to do something for your knee on all the other days of the year.

Mendable Knee is a one-time purchase you use in your own lounge room, for as long as your knee needs it. And the more you get, the less each one costs: two for A$179 (A$89.50 each), or three for A$229 (A$76.33 each).

Included free: The Knee Pain Survival Guide (e-book).

When your knee hurts, you move less. When you move less, the knee gets stiffer. A stiffer knee hurts more. And the next appointment starts to feel a long way off.

Add a public waiting list and the wait can stretch even further. One Australian wrote on a public forum: "I know country Qld where I was is 3 years just for specialist."

And for some people, the next needle is a worry of its own. As one Australian wrote on a public patient feedback site: "I was anxious about having the injection and feel like next time will be even more challenging"

Twelve minutes of warmth, compression and gentle vibration before you get moving can help the knee feel looser and more comfortable, so it's easier to keep moving between appointments.

An injection means a referral, an appointment, a waiting room and a needle. One Victorian wrote on an Australian forum about his own knee injection: "Had one in the knee and concurr with the "Hurts like bloody hell" message."

Mendable Knee is the opposite. Wrap it around the knee, fasten the strap and press start. Twelve minutes later, you're done. Watch the news. Have a cup of tea. Do it again tomorrow.

No appointments. No needle. No travel.

And because it only takes 12 minutes, it's something people actually keep doing, every single day. The extension strap is included for larger frames.

More comfort getting out of the chair. Steadier on the stairs. Back in the garden. Not miracles, just what can happen when your knee gets looked after every day, not only on injection day.

Use Mendable Knee every day for up to 90 days. Put it through your worst knee days. If it's not for you, send it back within those 90 days for a full refund.

And for the next two years, your device is covered by the 2-Year Replacement Warranty.

No pressure. No catch. Just a fair go.