What is a cortisone injection?
Cortisone (a corticosteroid) is a strong anti-inflammatory medicine. When it is injected into or around a painful part of the shoulder, it reduces inflammation in that area, which can ease pain and make it easier to move and exercise.
A local anaesthetic is usually given with the cortisone. A cortisone injection does not repair a torn tendon or worn cartilage. It is used to settle pain and inflammation, so that you can get on with physiotherapy and your normal activities.
Which shoulder problems can it help?
A cortisone injection may be used for:
- Subacromial bursitis and rotator cuff tendinopathy: inflammation around the rotator cuff, causing pain when lifting the arm.
- Frozen shoulder: an injection into the shoulder joint, usually early in the condition.
- Shoulder arthritis: an injection into the ball-and-socket joint.
- AC joint arthritis: an injection into the small joint on top of the shoulder.
- Long head of biceps problems: an injection around the biceps tendon, in the groove at the front of the shoulder (the bicipital groove).
An injection works best when it is aimed at the right problem, which is why getting the diagnosis right comes first. Shoulder pain can also come from the neck, and a shoulder injection will not help that. See Why does my shoulder hurt?
How Dr Constantin uses cortisone injections
- Image-guided injections: Dr Constantin prefers to send patients to a sports physician or radiologist, who performs the injection using ultrasound or other image guidance. This is particularly important when the injection needs to go into the shoulder joint or around the biceps tendon in the bicipital groove.
- Dr Constantin's rule: no more than one injection every 3 months, and no more than two injections. This is Dr Constantin's own rule. It is not proven in the research.
- Keep a pain diary: after your injection, keep a pain diary or a note in your phone of how your shoulder feels. Dr Constantin will then review your symptoms at about 3 months.
We don't really know how many injections someone should have, how long they last, or if they even provide long-term benefit. Certainly, repeated injections are not good for the soft tissues. They increase the risk of infection and make the tendon quality worse.
However, with one or two injections the harm and risk are minimal. An injection helps reduce your pain and inflammation, and then allows you to rehabilitate your shoulder to help you avoid surgery.
If the injections don't work, or pain is still a big issue after 3 to 6 months, then it is the right time to start talking about surgical options to improve your quality of life.
Does a cortisone injection work straight away?
No. The local anaesthetic works straight away, but it wears off in 12 to 24 hours, so the pain may come back after the first day.
The cortisone can take 2 to 3 weeks to start working, and it does not reach its full effect until about 6 weeks after the injection. So be patient, and do not assume the injection has not worked until you have given it a good 6 to 12 weeks.
Cortisone injections and surgery
If you and Dr Constantin decide that surgery is the right option, you will need to wait 3 to 6 months after a cortisone injection before your operation. This is because a cortisone injection can increase the risk of infection around the shoulder after surgery, including infection of a shoulder replacement (prosthetic joint infection). Waiting 3 to 6 months is what the recommended guidelines state.
Please tell Dr Constantin if you have had a cortisone injection, and when, so that your surgery can be planned safely.
Side effects and risks
Most people have no problems after a cortisone injection, but side effects can happen. These include:
- Pain flare: the shoulder can be sore for a day or two after the injection.
- Facial flushing: a warm, red face for a day or two.
- Raised blood sugar: if you have diabetes, your blood sugar may rise for a few days, so check it more often.
- Skin changes: thinning or lightening of the skin where the needle went in.
- Tendon damage: repeated injections can weaken tendons, which is one reason Dr Constantin limits the number of injections.
- Infection: rare, but serious. Seek medical help straight away if your shoulder becomes hot, red and swollen, or you have a fever, after an injection.
What does the research show?
Research on cortisone injections for shoulder pain shows variable results. A Cochrane review of 26 trials (Buchbinder et al. 2003) found that cortisone injections may help shoulder pain, but the effect may be small and may not last. The main benefit is in frozen shoulder.
- Frozen shoulder: an injection into the joint reduces pain for the first 6 to 8 weeks and improves movement. It works best in the first year, combined with a home exercise program (Cochrane review, Wang et al. 2017, Challoumas et al. 2020).
- Rotator cuff problems and bursitis: the benefit is small and may not last, and an injection was no better than anti-inflammatory tablets (Cochrane review). A large UK trial of 708 patients (GRASP, Hopewell et al. 2021) found that an injection into the bursa gave a modest improvement in pain and function at 8 weeks, but no benefit at 6 or 12 months.
- Before surgery: an injection in the 3 months before a shoulder replacement was linked with a higher risk of infection in the new joint (Akhtar et al. 2024).
What does this mean for you?
Will a cortisone injection fix my rotator cuff tear? This is a very common question.
What we do know is that a cortisone injection can help treat the pain from the tear, or from the inflammation around the shoulder, so that you can do physiotherapy to recover your range of motion. This may be enough for you to have a pain-free and functional shoulder.
But a cortisone injection does not cure you or make your tear heal. The natural history of rotator cuff tears is that about 50% of them will progress (get bigger) at about 3 years, even after a good period of no symptoms.
Frequently asked questions
Do cortisone injections work for shoulder pain?
Results are variable. The main benefit is in frozen shoulder, where an injection into the joint can reduce pain and improve movement, especially in the first year. For rotator cuff problems and bursitis the benefit is often small and may not last. An injection works best when it is aimed at the right problem and combined with physiotherapy.
Does a cortisone injection work straight away?
No. The local anaesthetic works straight away but wears off in 12 to 24 hours. The cortisone takes 2 to 3 weeks to start working and reaches its full effect at about 6 weeks, so give it a good 6 to 12 weeks before deciding whether it has worked.
How many cortisone injections can I have in my shoulder?
We don't really know how many injections someone should have. Repeated injections are not good for the soft tissues, so Dr Constantin's own rule, which is not proven in the research, is no more than one injection every 3 months, and no more than two. If the injections don't work, or pain is still a big issue after 3 to 6 months, it is the right time to start talking about surgical options.
Who gives the injection?
Dr Constantin prefers to send patients to a sports physician or radiologist, who performs the injection using ultrasound or other image guidance. This helps make sure the cortisone goes to the right place, particularly in the shoulder joint and around the biceps tendon.
Will a cortisone injection fix my rotator cuff tear?
No. A cortisone injection can help treat the pain from the tear, or from the inflammation around the shoulder, so that you can do physiotherapy to recover your range of motion, and this may be enough for you to have a pain-free and functional shoulder. But it does not cure you or make the tear heal. About 50% of rotator cuff tears get bigger at about 3 years, even after a good period of no symptoms. See Rotator cuff repair.
How long after a cortisone injection can I have shoulder surgery?
You should wait 3 to 6 months after a cortisone injection before shoulder surgery, as an injection can increase the risk of infection after surgery, including infection of a shoulder replacement.
Do cortisone injections damage tendons?
Repeated injections are not good for the soft tissues. They increase the risk of infection and make the tendon quality worse. With one or two injections the harm and risk are minimal, which is why Dr Constantin limits cortisone injections to two.
Do I need a referral?
Yes. You'll need a referral from your GP or another specialist to see Dr Constantin. See Referrals.
Book an appointment
If your shoulder pain is not settling, or you are wondering whether a cortisone injection is right for you, Dr Constantin can assess your shoulder and talk through your options. Please contact Dr Constantin for an assessment, or call (02) 9409 0503.
If you need surgery, it will be performed at the Mater Hospital (private health insurance, DVA, workers compensation and CTP) or Canterbury Hospital (Medicare).
Related pages
The information on this page is general in nature and is not a substitute for individual medical advice. Recovery timeframes are a guide only and will be tailored to you.
Book a shoulder assessment
A GP or specialist referral is needed to claim a Medicare rebate. Consultations are available in North Sydney, Kogarah and Miranda.