Painful Arc Syndrome | Nuffield Health

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What is painful arc syndrome?

Painful arc syndrome, also called shoulder impingement, is a common cause of shoulder pain that happens when the tendons and cushioning tissue in your shoulder become irritated as your arm moves. There is pain within a specific part of your arm's range of movement, usually when lifting it to the side or overhead, with less or no pain outside that range.

What are the symptoms of painful arc syndrome?

The main symptom is shoulder pain that occurs only within a certain range as you lift your arm, usually between around 60 and 120 degrees, easing again once your arm goes higher. You might also notice:

pain felt at the front, side or back of your shoulder, sometimes spreading down your upper arm
pain that's worse when reaching overhead or out to the side, such as reaching for a high shelf
difficulty with everyday tasks like doing your hair or getting dressed
weakness in the shoulder
night pain, especially when lying on the affected side
A grinding or popping sensation when you move your shoulder.

What are the causes of painful arc syndrome and who is at risk?

Painful arc syndrome happens when tendons or the fluid-filled cushion (bursa) in your shoulder become irritated as they pass through a narrow space beneath a bony arch, called the subacromial space, when you lift your arm. Common causes include:

Rotator cuff tendinitis: inflammation of the tendons that stabilise your shoulder, most often from repetitive overhead activity or overuse, though it can also follow a specific injury
Subacromial bursitis: inflammation and swelling of the cushioning bursa
Bone spurs or arthritis in a nearby joint (the acromioclavicular joint), which narrow the space available
A partial tear in a rotator cuff tendon.

You're more at risk if you regularly do repetitive overhead activities, such as swimming, throwing sports or overhead manual work.

Are there different types of painful arc syndrome?

'Painful arc syndrome' and 'shoulder impingement' are umbrella terms that can cover a number of related shoulder problems, depending on which structure is mainly affected:

Rotator cuff tendinitis or tendinopathy: inflammation or wear of the tendons
Subacromial bursitis: inflammation of the cushioning bursa
Acromioclavicular (AC) joint arthritis: wear and tear in the small joint at the top of your shoulder
Long head of biceps tendon pain: irritation of a biceps tendon that also runs through this area
A partial rotator cuff tear.

How is painful arc syndrome diagnosed?

Your doctor or physiotherapist can usually diagnose painful arc syndrome from your symptoms and a physical examination, including the 'painful arc test', where they watch your shoulder movement to see exactly when pain occurs as you raise your arm. They may also arrange:

An X-ray, to look for bone spurs or changes in the acromioclavicular joint
An ultrasound scan, which can also show your tendons and bursa moving in real time as you lift your arm
An MRI scan, for a more detailed look at your rotator cuff and joint structures, particularly if an ultrasound doesn't explain your symptoms.

Scan results don't always match symptoms exactly. Some people have bone spurs or tendon changes on a scan without any pain, while others have significant pain with a normal scan, so your doctor will consider your scan alongside your symptoms and examination rather than relying on imaging alone.

How is painful arc syndrome treated?

Non-surgical treatment

Most people improve with non-surgical treatment, which usually combines several of the following:

Modifying activities that bring on your pain, such as overhead work or repetitive lifting, rather than complete rest
Anti-inflammatory painkillers, and ice packs applied for 15 to 20 minutes at a time
Physiotherapy, focused on strengthening your rotator cuff and shoulder blade muscles, improving posture, and gradually building back up to your normal activities
A steroid injection into your shoulder, if pain is severe or is stopping you from progressing with physiotherapy exercises.

Recovery times vary. Mild cases may settle within 6 to 8 weeks, while more longstanding cases can take 3 to 6 months of progressive rehabilitation.

Surgical treatment

Surgery is usually only considered if a proper course of non-surgical treatment hasn't helped, or if there's a clear structural cause such as a large bone spur or a full-thickness rotator cuff tear.

The operation, known as subacromial decompression, aims to create more space for the tendons by removing bone or damaged tissue, and can be done arthroscopically (keyhole surgery) or as open surgery.

For many people, the results of this surgery are similar to those from a well-structured course of physiotherapy, so it isn't automatically the next step if conservative treatment hasn't fully worked.

When should I see a doctor?

See a doctor or physiotherapist if your shoulder pain lasts more than two weeks, disturbs your sleep, or comes with weakness or restricted movement. Get checked promptly if:

You suddenly lose the ability to lift your arm after an injury, which can suggest a rotator cuff tear
Your shoulder feels stiff in every direction, not just when lifting your arm, which can suggest a frozen shoulder
You have pain deep in the joint with catching or locking
Moving your neck brings on your shoulder symptoms.

FAQs

Is painful arc syndrome the same as shoulder impingement?

Yes, these terms are generally used to mean the same thing. You may also hear it called subacromial impingement, subacromial pain syndrome, or rotator cuff related shoulder pain. The newer terms reflect a better understanding that the pain often relates to how well your tendons are coping with load, not just a mechanical pinch.
Does having a bone spur mean I'll need surgery?

Not necessarily. Bone spurs are common on shoulder scans, including in people who have no shoulder pain at all. Your doctor will look at your scan alongside your symptoms and examination, rather than treating the spur alone as the cause or the reason for surgery.
How common is shoulder pain like this?

Shoulder problems are very common. Studies suggest around half the population experiences at least one episode of shoulder pain each year, and over half of those affected still have some symptoms three years later.
Can I keep using my shoulder while it heals?

Yes, in most cases. Complete rest isn't usually recommended, as it can weaken your shoulder further. Instead, it usually helps to modify the activities that bring on your pain while staying gently active, then gradually build your strength back up.
What's the difference between painful arc syndrome and a frozen shoulder?

With painful arc syndrome, you can usually still move your arm through a full range if someone else moves it for you, and pain typically occurs only in the middle part of lifting your arm. With a frozen shoulder, movement is restricted in every direction, even when someone else tries to move your arm for you.

Related tests and scans

X-ray

An X-ray machine produces images of the inside of the body. It is effective in assessing bones and other dense structures within the body.

Related treatments and procedures

Shoulder manipulation

Shoulder manipulation is a treatment for frozen shoulder, that consists of stretching and releasing the shoulder capsule.

Shoulder stabilisation surgery

Living with an unstable shoulder can be painful and limiting. Our experts at Nuffield Health offer shoulder stabilisation surgery, a procedure that repairs the damaged cartilage and ligaments to stop your shoulder from dislocating again.

Shoulder surgery (rotator cuff repair)

The rotator cuff is formed of four tendons and the adjacent muscles that attach your arm to the top of your shoulder blade, which gives the shoulder stability and control. Tears to the rotator cuff tendon can occur for many reasons including acute injury, overuse or normal age-related changes.