A cortisone injection calms inflammation inside the knee and can relieve arthritis pain for a few weeks, sometimes a few months. UK NICE guidelines suggest it for short-term relief when other treatments have not worked well enough, alongside exercise.
What to expect
- A quick injection in the clinic, sometimes guided by ultrasound
- Relief often starts within days
- Rest the knee from heavy activity for a day or two
Limits
- Relief is temporary
- Doctors usually limit injections to a few per year in the same knee
- Some studies raise concerns that frequent injections may speed cartilage loss
- Can raise blood sugar for a few days in people with diabetes
If cortisone no longer helps, doctors may discuss PRP, stem cells or surgery.