Most patients begin to notice improvement within 3–7 days after a cortisone injection for calcific tendonitis.
Some feel relief sooner, while maximum benefit is usually experienced within 1–2 weeks.
Why Doesn’t It Work Immediately?
A cortisone injection does not act like a local anaesthetic alone. While the injection may contain anaesthetic that gives short-term relief for a few hours, the steroid component takes time to reduce inflammation.
Cortisone works by:
- Reducing inflammation around the calcium deposit
- Settling irritation in the subacromial bursa
- Decreasing swelling in the rotator cuff
- Lowering pain signals in the affected area
Because inflammation needs time to settle, improvement is gradual rather than instant.
Typical Timeline After a Cortisone Injection
Here is what most patients experience:
First 24 hours
- Possible mild soreness at the injection site
- Temporary numbing from local anaesthetic
2–3 days
- Some patients notice early improvement
- In rare cases, a temporary “steroid flare” (short-term increase in pain)
3–7 days
- Clear reduction in shoulder pain
- Improved range of movement
1–2 weeks
- Maximum anti-inflammatory effect
- Significant improvement in daily function
How Long Does Relief Last?
Relief from an ultrasound-guided cortisone injection for calcific tendonitis can last:
- Several weeks
- Several months
The injection reduces inflammation but does not directly dissolve the calcium deposit. In many cases, once inflammation settles, the body gradually reabsorbs the calcium naturally.
Why Ultrasound Guidance Matters
At Alton Pain Clinic, all shoulder injections are performed using ultrasound guidance, which allows us to:
- Precisely target the inflamed subacromial space
- Avoid surrounding structures
- Improve accuracy
- Enhance clinical outcomes
Research shows ultrasound-guided shoulder injections are more accurate than blind injections, leading to better results.
When Should You Consider a Cortisone Injection?
You may benefit if you have:
- Severe shoulder pain
- Night pain affecting sleep
- Limited shoulder movement
- Imaging-confirmed calcific tendonitis
- Persistent inflammation not settling
Early treatment can shorten recovery time and reduce prolonged discomfort.
Frequently Asked Questions
Does a cortisone injection work straight away?
Not usually. Most patients notice improvement within 3–7 days.
Can pain worsen before it improves?
A temporary steroid flare can occur but typically settles within 48 hours.
How long does the relief last?
Relief may last several weeks to months.
Does the injection remove the calcium deposit?
No, it reduces inflammation while the body gradually reabsorbs the calcium.
Are ultrasound-guided injections more effective?
Yes. They improve precision and treatment outcomes.