Subacromial decompression

Expert reviewer, Dr Roger Tillman, Consultant Orthopaedic Surgeon
Next review due September 2019

Subacromial decompression (acromioplasty) is an operation on your shoulder. It’s used to treat a condition called shoulder impingement. This is when the bones and tendons in your shoulder rub against each other when you raise your arm, causing pain.

The word ‘subacromial’ means ‘under the acromion’. The acromion is part of your shoulder blade (scapula), and it helps to form your shoulder joint.

If you’re having a subacromial decompression procedure it will probably be done through keyhole surgery (arthroscopy) under a general anaesthetic. Most people get to go home on the same day. Find out more about having the procedure in our section ‘what happens during subacromial decompression’ below.

A couple sitting on the grass

What is shoulder impingement?

If you have shoulder impingement, a bone at the top of your shoulder rubs against the tendons in your shoulder when you raise your arm. This causes pain when you try to raise your arm, and restricts your movement.

There’s normally a space between the top of your arm bone and the bone at the top of your shoulder blade, called the subacromial area. A small, fluid-filled sac (bursa) in this space allows the tendons between your upper arm and shoulder to glide freely when you move your arm. Your surgeon may mention the words ‘rotator cuff’. This is the name given to the muscles and tendons surrounding the top of your upper arm bone, attaching it to your shoulder blade.

In subacromial impingement, the amount of space between your shoulder blade and rotator cuff tendons is reduced. This may be due to irritation and swelling of the bursa. It can also be caused by the development of growths (bony spurs) on the top of your shoulder blade. These occur because of ‘wear and tear’ arthritis (osteoarthritis).

Subacromial decompression can open up this space by removing any swollen or inflamed bursa, and any bony spurs.

Preparing for subacromial decompression

Your operation will be carried out by an orthopaedic surgeon (a doctor who specialises in bone surgery). They’ll explain how to prepare for your procedure. For example, if you smoke, you’ll be asked to stop. Smoking increases your risk of getting a chest or wound infection, which can slow your recovery.

Before you go into hospital you’ll need to make some preparations for after your surgery. The operation is usually done as a day case, which means you won’t have to stay overnight in hospital. You’ll need to arrange for a friend or family member to collect you from hospital after your surgery and take you home. And make plans for someone to be with you for at least the first day after you come home.

You’ll probably be having a general anaesthetic during your operation, so you’ll be asked to follow fasting instructions. This means not eating or drinking, typically for about six hours beforehand. Follow your anaesthetist or surgeon’s advice carefully.

Your surgeon will discuss with you what will happen before, during and after your procedure, and any pain you might have. This is your opportunity to ask questions so that you understand what will be happening. You don’t have to go ahead with the procedure if you decide you don’t want it. Once you understand the procedure and if you agree to have it, you’ll be asked to sign a consent form.

What are the alternatives to subacromial decompression?

For some people, subacromial decompression isn’t necessary. Shoulder pain has various causes and the symptoms can often be managed with other options such as:

Your surgeon will usually only recommend you have subacromial decompression if other treatments haven’t worked for you.

What happens during subacromial decompression?

Subacromial decompression can take around an hour, depending on how complicated your operation is. The operation is usually done as a keyhole procedure using a narrow, flexible, tube-like telescopic camera called an arthroscope.

Subacromial decompression is usually done under general anaesthesia, which means that you’ll be asleep during the procedure. You may also be given a local (regional) anaesthetic into the nerves around your shoulder. This helps to reduce any pain you may feel after your operation. Once the anaesthetic has taken effect, your surgeon will make small cuts in the skin around your shoulder. Usually there will be three small cuts, but sometimes more are needed.

Your surgeon will look into the area called the subacromial space within your shoulder. This will be either directly through the arthroscope, or at pictures sent from the arthroscope to a monitor. They’ll insert specially designed surgical instruments through the small cuts and reshape this part of your shoulder blade. Your surgeon may also decide to repair any damaged tendons at the same time. This may mean your surgeon has to change from keyhole surgery to an open operation and will make a larger cut in your shoulder. See our FAQ on arthroscopy or open surgery below for more information.

At the end of the operation, your surgeon will remove the surgical instruments and close the cuts, usually with stitches.

What to expect afterwards

You’ll need to rest until the effects of the anaesthetic have passed. Let your nurse know if you’re in pain. You’ll be offered pain relief to help with any discomfort as the anaesthetic wears off.

You’ll usually be able to go home when you feel ready. Someone else should drive you home. Try to have a friend or relative stay with you for the first 24 hours.

Having general anaesthesia can temporarily affect your co-ordination and reasoning skills. So don’t drive, drink alcohol, operate machinery or sign legal documents for 24 hours afterwards. If you’re in any doubt about driving, contact your motor insurer so that you’re aware of their recommendations, and always follow your surgeon’s advice.

Before you leave hospital your nurse will give you advice about caring for your wounds, and what to do about any stitches you have. You may need to keep your arm in a sling for a few days after your operation.

Recovering from subacromial decompression

You’ll need to be patient, as it usually takes between two and four months to make a full recovery from subacromial decompression, sometimes longer. But the operation is successful in between eight and nine out of 10 people.

If you need pain relief, you can take over-the-counter painkillers such as paracetamol or ibuprofen. Always read the patient information leaflet that comes with the medicine and if you have any questions, ask your pharmacist for advice.

You may see a physiotherapist (a health professional who specialises in maintaining and improving movement and mobility) after your operation. It’s really important that you do any exercises that your physiotherapist or surgeon recommends. These may help you to recover more quickly. Your surgeon or physiotherapist will tell you when to start these exercises, and how many to do.

You may be able to return to work within a few days of your procedure. However, this will depend on how complicated your operation was and the type of job you have. Ask your surgeon or physiotherapist for advice about returning to work and other activities.

Side-effects of subacromial decompression

Side-effects are the unwanted but mostly temporary effects you may get after having the procedure.

You may have some pain and stiffness around your shoulder after surgery. This may make moving around uncomfortable at first.

If you develop any of the following symptoms, contact your hospital immediately as it may indicate you have an infection or other complication.

  • Your wound becomes hot, red or swollen.
  • Your wound bleeds or becomes more painful.
  • You have a high temperature.

Complications of subacromial decompression

Complications are when problems occur during or after the procedure. It’s not possible to say for sure how likely each person is to get these – ask your surgeon how these risks might apply to you.

There are several possible complications of any operation. These include an unexpected reaction to the anaesthetic, a blood clot in the veins of your leg (deep vein thrombosis, DVT), excessive bleeding or infection.

A possible complication of subacromial decompression is accidental damage to your shoulder blade or another part of your shoulder joint, including nerves or blood vessels.

Subacromial decompression surgery is successful in between eight and nine out of 10 people. This means that in one or two out of 10 people the surgery is unsuccessful, and they will continue to have shoulder symptoms.

Frequently asked questions

  • Your surgeon or physiotherapist will give you a range of exercises to do after your surgery. It’s important to do these exercises as they will help you to recover more quickly. These may include exercises to:

    • stretch the muscles around your shoulder
    • improve the range of motion of your shoulder
    • improve the strength of your muscles around your shoulder

    Your physiotherapist will tell you when you can start these exercises, and how many you need to do. You’ll have exercises to do at home and you may also be offered a course of hospital-based physiotherapy sessions.

    It may take several months after your operation to completely recover. However, you’ll probably be able to get back to your usual activities after about two to four months.

  • Whether you have open or arthroscopic surgery will depend on the problems you’re having with your shoulder and your medical history. Your surgeon will talk to you about what’s best in your situation.

    It’s common for shoulder surgery to be done using an arthroscopic technique. This means your surgeon will make small cuts in your shoulder to pass specially adapted surgical equipment through to repair your shoulder. Having just small cuts may reduce the pain you have after surgery. It may also mean you recover more quickly than with open surgery – getting back to your usual activities sooner.

    Open surgery means your surgeon makes a larger cut in your shoulder. This allows your surgeon to see your shoulder blade, rotator cuff muscles and tendons directly. Sometimes your surgeon may have to convert from using arthroscopic surgery to open surgery if your rotator cuff tendons need to be repaired as well.

    Doctors aren’t sure yet, but it doesn’t seem that you’re any more likely to get complications after open surgery than arthroscopic surgery.

    Ask your surgeon to explain which is the best option for you in your circumstances.

About our health information

At Bupa we produce a wealth of free health information for you and your family. We believe that trustworthy information is essential in helping you make better decisions about your health and care. That’s why our content is produced to the highest quality standards. Look out for the quality marks on our pages below. You can find out more about these organisations and their standards on The Information Standard and HON Code websites.

Information standard logo  This website is certified by Health On the Net Foundation. Click to verify.

Learn more about our editorial team and principles >

Related information

    • Shoulder impingement syndrome treatment and management. Medscape., updated 23 June 2015
    • Shoulder pain. NICE Clinical Knowledge Summaries., last revised April 2015
    • Map of Medicine. Shoulder pain. International View. London: Map of Medicine; 2015 (Issue 5)
    • Coghlan J, Buchbinder R, Green S, et al. Surgery for rotator cuff disease. Cochrane Database of Systematic Reviews 2008, Issue 1. doi: 10.1002/14651858.CD005619.pub2
    • Shoulder impingement/rotator cuff tendinitis. American Academy of Orthopaedic Surgeons., last reviewed February 2011
    • Shoulder arthroscopy. American Academy of Orthopaedic Surgeons., last reviewed April 2011
    • Shoulder surgery. American Academy of Orthopaedic Surgeons., published August 2009
    • Kulkarni R, Gibson J, Brownson P et al. Subacromial shoulder pain. BESS/BOA Patient Care Pathways. Shoulder & Elbow 2015; 7(2):135–43. doi: 10.1177/1758573215576456
    • Managing rotator cuff disorders. Arthritis Research UK., published 2010
    • What causes shoulder pain? Arthritis Research UK. www.arthritisresearchuk, accessed 9 August 2016
  • Reviewed by Dr Kristina Routh, Freelance Health Editor, August 2016
    Expert reviewer, Dr Roger Tillman, Consultant Orthopaedic Surgeon
    Next review due September 2019

Has our health information helped you?

We’d love to know what you think about what you’ve just been reading and looking at – we’ll use it to improve our information. If you’d like to give us some feedback, our short survey will take just a few minutes to complete. And if there's a question you want to ask that hasn't been answered here, please submit it to us. Although we can't respond to specific questions directly, we’ll aim to include the answer to it when we next review this topic.