Overview

Shoulder impingement syndrome is a common cause of shoulder pain, particularly in individuals who perform repetitive overhead activities. It occurs when the tendons of the rotator cuff and the bursa (a fluid-filled sac that reduces friction) are compressed or “impinged” during shoulder movements. Left untreated, impingement can progress to tendon tears or long-term dysfunction. Early diagnosis and appropriate treatment are essential to prevent worsening symptoms and restore full shoulder function.

Anatomy of the Shoulder

The shoulder is a highly mobile joint where the head of the humerus (upper arm bone) fits into the shallow socket of the scapula (shoulder blade). The rotator cuff—a group of four muscles and their tendons—stabilises the shoulder during movement.

Above the rotator cuff lies the acromion, a bony part of the scapula. The subacromial space is between the rotator cuff and the acromion, which houses the subacromial bursa. During arm elevation, this space naturally narrows slightly. In shoulder impingement, further narrowing causes the rotator cuff tendons and bursa to become compressed and inflamed.

Causes of Shoulder Impingement

The most common causes of shoulder impingement involve repetitive overhead movements, overuse injury, and anatomical factors that narrow the space where the rotator cuff tendons and bursa pass through.

Repetitive overhead activity:

• Sports like swimming, tennis, and weightlifting
• Occupational tasks involving overhead work (e.g., painting, construction)

Structural factors:

• Variations in the shape of the acromion (e.g., hooked acromion)
• Bone spurs

Functional factors:

• Muscle weakness or imbalance
• Poor shoulder blade control (scapular dyskinesis)

A history of rotator cuff injury or instability can also predispose individuals to impingement.

Symptoms of Shoulder Impingement

The most typical symptoms of shoulder impingement include:

• Pain when lifting the arm, particularly overhead or behind the back
• Pain at night, especially when lying on the affected side
• A feeling of weakness in the shoulder
• Difficulty reaching for objects up high, or performing overhead tasks
• A painful arc of motion (pain between approximately 60°–120° of arm elevation)

In chronic cases, stiffness and decreased range of motion may develop.

How to Diagnosis Frozen shoulder

Diagnosis is based on a combination of clinical examination and imaging:

• Physical examination: Specific tests such as Neer’s and Hawkins-Kennedy impingement signs reproduce the characteristic pain.
• X-rays: Assess bone structure, acromial shape, and possible spurs.
• Ultrasound scan: Visualises the rotator cuff tendons and subacromial bursa for signs of inflammation or tears.
• MRI scan: Provides a detailed assessment of soft tissues, particularly when a rotator cuff tear is suspected.

Differential Diagnosis

There are a number of conditions that may present similarly to shoulder impingement. It’s important to exclude these so your consultant will also be looking for potential problems such as:

• Rotator cuff tears
• Calcific tendinitis
• Shoulder bursitis
• Glenohumeral osteoarthritis
• Labral tears
• Cervical radiculopathy (nerve compression in the neck)

A thorough subjective and clinical examination will help ensure an accurate diagnosis and effective management. And at LBO we are lucky to have access to a full spectrum of diagnostic and scanning equipment and technologies.

Treatment Options

Non-Surgical Management for Shoulder Impingement

Initial treatment for shoulder impingement is almost always non-surgical:

• Activity modification: Avoid aggravating overhead activities.
• Physiotherapy: Focused on improving rotator cuff strength and restoring normal scapular mechanics.
• Anti-inflammatory medications (NSAIDs): Help to control pain and inflammation.
• Subacromial corticosteroid injection: Reduces inflammation and provides temporary pain relief, aiding engagement with physiotherapy.
• Shockwave therapy: Occasionally used if calcific tendinitis is contributing to impingement.

Most patients experience significant improvement over 6–12 weeks with a structured rehabilitation programme.

Surgical Treatment for Shoulder Impingement

If conservative management has not been effective, then there are other options that might be available to you.
Surgery may be considered when:

• Symptoms persist despite at least 4-6 months of appropriate non-surgical treatment
• Imaging shows significant structural impingement or associated rotator cuff damage

Surgical options include:

Arthroscopic Subacromial Decompression:

• A minimally invasive “keyhole” surgery performed, usually under general anaesthetic
• Involves shaving part of the underside of the acromion (acromioplasty) and removing inflamed tissue to increase space for the rotator cuff tendons.
• If a rotator cuff tear is identified, it can be repaired during the same procedure.

Outcomes:

• The majority of patients undergoing subacromial decompression experience good to excellent outcomes, with marked improvement in pain and function.
• Patients can often return to full activity, including a gradual return to sports by 4-6 months postoperatively.
• Complications are rare but may include infection, stiffness, or persistent pain if a concurrent rotator cuff tear is not addressed.

Frequently Asked Questions

Can shoulder impingement heal without surgery?
Yes, many cases respond well to non-surgical treatments such as physiotherapy and injections, particularly when started early.

How long does it take to recover from shoulder impingement?
With non-surgical treatment, recovery often takes 6–12 weeks. Post-surgical recovery may take 3–6 months depending on the severity and individual healing.

What exercises should I avoid with shoulder impingement?
Avoid heavy overhead lifting, behind-the-neck presses, and activities that provoke pain until your clinician or physiotherapist advises otherwise.

Is a corticosteroid injection a cure for shoulder impingement?
No, corticosteroid injections are used to reduce inflammation and pain but must be combined with physiotherapy to address the underlying cause and ensure proper rehabilitation.

What happens if shoulder impingement is left untreated?
Persistent impingement can lead to rotator cuff degeneration and tears, worsening pain, weakness, and long-term loss of shoulder function.