Subacromial Impingement Syndrome: Symptoms, Causes, Treatment & Exercises

Key Takeaways

• Subacromial impingement syndrome is a painful condition where shoulder tendons become compressed between the humeral head and acromion.

• Symptoms are debilitating pain at night and sleep disturbances, with mechanical symptoms such as catching or clicking sensations during certain shoulder movements.

• The condition frequently results from a combination of anatomical factors and repetitive overhead activities, making certain professions and sports participants particularly vulnerable to developing symptoms.

• Early intervention through targeted physical therapy and appropriate activity modification is crucial to prevent progression to more serious rotator cuff tears that require surgical management.

• At MSK Doctors, we use advanced AI movement analysis technology to identify precise musculoskeletal factors contributing to your shoulder impingement syndrome and develop unique treatments for comprehensive management. 

Subacromial Impingement Syndrome Overview

Understanding Shoulder Anatomy

To fully grasp what subacromial impingement syndrome entails, understanding the basic anatomy of the shoulder is necessary. 

The shoulder is a complex joint composed of three main bones: the humerus (upper arm bone), the scapula (shoulder blade), and the clavicle (collarbone). The rotator cuff, a group of muscles and tendons, surrounds the shoulder joint, stabilising it and enabling a wide range of motion (image courtesy of Cleveland Clinic).

Between the acromion and the rotator cuff tendons lies the subacromial bursa, a fluid-filled sac that reduces friction and allows smooth movement. 

Subacromial impingement syndrome occurs when the tendons of the rotator cuff and the subacromial bursa are compressed or pinched under the acromion. Over time, this repeated compression can lead to inflammation, pain, and even tears in the tendons.

Impact on Daily Life

Subacromial impingement syndrome can significantly impact one's daily life. 

Simple tasks like reaching for an object on a high shelf, lifting groceries, or even putting on a shirt can become painful and challenging. 

The discomfort can disrupt sleep, making it difficult to find a comfortable position. Moreover, if left untreated, the condition can worsen, potentially leading to rotator cuff tears that may require surgical intervention.

Symptoms of Subacromial Impingement

Pain with Overhead Activities

• Individuals with subacromial impingement syndrome typically experience sharp or aching pain when performing overhead movements such as reaching for objects on high shelves, washing hair, throwing, or participating in racquet sports. 

• This pain pattern is particularly characteristic, as it occurs within a specific arc of motion (typically between 60-120 degrees of shoulder abduction) often called the "painful arc."

Night Pain and Sleep Disturbance

• Many patients report significant discomfort when lying on the affected shoulder, which can severely disrupt sleep patterns. 

• This nocturnal pain often occurs even without daytime symptoms and may force individuals to sleep in altered positions, potentially causing secondary neck or back issues.

Localised Tenderness and Swelling

• Physical examination frequently reveals point tenderness over the anterior and lateral aspects of the acromion and sometimes along the bicipital groove. 

• Visible or palpable swelling may be present due to inflammation of the subacromial bursa or rotator cuff tendons, particularly after activity that provokes symptoms.

Progressive Weakness and Limited Range of Motion

• As the condition advances, patients may notice gradual weakness, especially with lifting or overhead activities. This weakness stems from both pain inhibition and potential rotator cuff tendon damage. 

• Range of motion becomes increasingly restricted, with particular difficulty reaching behind the back (internal rotation) or to the side and back (combined extension and external rotation).

Catching, Clicking, or Crepitus

• Many individuals report mechanical symptoms such as a sensation of catching or clicking during certain shoulder movements. 

• Audible or palpable crepitus (a grinding or popping sound/sensation) may be present during shoulder rotation or elevation, indicating roughened surfaces of the inflamed tendons moving against the acromion.

Primary Causes

Overuse and Repetitive Motion

Activities that require repeated overhead movements, such as swimming, tennis, or painting, can place significant stress on the shoulder joint. Over time, this can lead to inflammation and impingement of the rotator cuff tendons.

Posture and Weakness Factors

Poor posture, especially when sitting or working at a desk, can lead to muscle imbalances and weakness in the shoulder area. Rounded shoulders or a forward head posture can alter the alignment of the shoulder joint, increasing the risk of shoulder impingement.

Treatment Options

Non-Surgical Solutions

For many individuals, non-surgical treatments can alleviate symptoms and improve shoulder function. These options are often the first line of defense and can include a combination of rest, medication, and lifestyle modifications. 

Resting the shoulder and avoiding activities that exacerbate pain is vital. Over-the-counter pain relievers, such as ibuprofen or acetaminophen, can help reduce inflammation and manage discomfort. Applying ice packs to the affected area may also provide relief.

Surgical Interventions

In cases where non-surgical treatments do not provide sufficient relief, surgical intervention may be considered. Surgery is typically reserved for severe cases where there is significant structural damage, such as a rotator cuff tear, or when conservative treatments have failed.

One common surgical procedure is subacromial decompression, which involves removing a small portion of the acromion to create more space for the rotator cuff tendons. This procedure can be performed arthroscopically, which is minimally invasive and often results in a quicker recovery.

Role of Physical Therapy

Therapists often use manual techniques, such as joint mobilisation and soft tissue massage, to reduce pain and improve mobility. Additionally, they may incorporate modalities like ultrasound or electrical stimulation to further enhance healing.

Exercises to Alleviate Symptoms

Strengthening Exercises

Strengthening the rotator cuff and surrounding muscles is crucial for stabilising the shoulder joint and reducing the risk of impingement. Exercises such as external rotations with resistance bands and scapular retractions can be particularly effective.

For example, to perform an external rotation:

1.  Attach a resistance band to a secure object. 

2. Stand with your elbow bent at a 90-degree angle and your upper arm close to your body. 

3. Rotate your forearm outward, keeping your elbow at your side. 

4. Perform 2-3 sets of 10-15 repetitions.

Stretching Techniques

Stretching the shoulder and surrounding muscles can help improve flexibility and reduce tension. The cross-body shoulder stretch is an effective way to target the posterior shoulder muscles. To perform this exercise:

1. Simply extend one arm across your chest and use the opposite hand to gently pull it closer to your body.

2. Hold each stretch for 15-30 seconds and repeat 2-3 times. 

3. It's important to stretch both sides to maintain balance and symmetry.

Posture Improvement Drills

Improving posture is essential for reducing the risk of subacromial impingement syndrome. Simple drills, such as wall angels and chin tucks, can help correct posture and alleviate strain on the shoulder joint.

Your Shoulder Health Journey With MSK Doctors

With MSK Doctors, you're choosing a proven pathway to restore shoulder function and return to the activities you love, supported by specialists who understand both the clinical and personal impact of shoulder pain.

At MSK Doctors, we understand that this common shoulder condition often begins subtly but can progressively limit your ability to perform even simple tasks like reaching overhead or sleeping comfortably.

Our specialist-led approach bypasses traditional referral pathways, providing immediate access to expert assessment. Using advanced MAI-Motion technology allows us to precisely identify the unique physiological factors contributing to your impingement—whether postural issues, muscle imbalances, or anatomical variations. 

Rather than generic treatment protocols, we develop highly individualised rehabilitation programmes targeting your specific needs. Our well-rounded approach incorporates evidence-based physical therapy, activity modification guidance, and when appropriate, cutting-edge interventional treatments.

Whether you're dealing with a recent shoulder injury or chronic discomfort, our team is here to support you every step of the way. Book your consultation with MSK Doctors today and start your journey to recovery.

Frequently Asked Questions (FAQ)

What is subacromial impingement syndrome?

Subacromial impingement syndrome occurs when the tendons of the rotator cuff are compressed under the acromion, leading to pain and restricted movement. It is often caused by repetitive overhead activities, poor posture, or anatomical factors that narrow the space in the shoulder joint.

What exercises are best for improving shoulder mobility?

• External rotations with resistance bands

• Scapular retractions

• Cross-body shoulder stretches

• Wall angels

Are there preventive measures for subacromial impingement?

Yes; maintain good posture, especially when sitting or working at a desk, incorporate shoulder-strengthening exercises into your fitness routine, avoid repetitive overhead activities that can strain the shoulder joint, and use proper techniques and equipment when engaging in sports or physical activities.

What are the risks of delaying treatment?

Delaying treatment for subacromial impingement syndrome can lead to a progression of symptoms and potentially more serious complications. 

How can MSK Doctors assist with shoulder issues?

At MSK Doctors, we provide a range of services to address shoulder conditions, including comprehensive assessments, personalised treatment plans, and rehabilitation programs.