Shoulder Impingement Syndrome: Overview and Evidence Summary

Condition Overview

Shoulder impingement syndrome refers to pain and functional limitation caused by irritation or compression of structures within the subacromial space—most commonly the supraspinatus tendon or the subacromial bursa. While the term “impingement” was once used to imply a purely mechanical process, modern research recognizes it as a multifactorial condition involving tendon load tolerance, neuromuscular control, posture, scapular motion, and sometimes structural factors such as acromial shape or osteophytes.

Patients typically report pain during overhead activities, reaching away from the body, or lifting objects in front of them. A common feature is the “painful arc,” where mid-range elevation triggers discomfort, while lower and higher portions of the movement feel easier. Night pain, especially when lying on the affected shoulder, is also frequently described.

Importantly, the majority of symptomatic cases are not caused by physical “pinching” alone. Changes in rotator cuff coordination, fatigue, or altered scapular mechanics can all reduce the subacromial space or increase tendon stress. Because of this, rehabilitation focuses on improving movement patterns, restoring muscle balance, and increasing tendon resilience—rather than relying solely on strategies intended to create more space.

Shoulder impingement responds very well to structured conservative care. With targeted exercise and appropriate load management, most individuals recover without injections or surgery.

Summary of Current Evidence for Shoulder Impingement Syndrome

Evidence-Based Management Discussion

Contemporary Understanding

Traditional models portrayed impingement as a simple mechanical problem, where the supraspinatus tendon or bursa became physically pinched under the acromion. Newer research shows that this view is too narrow. Many people with structural narrowing experience no pain, and many with symptoms show no meaningful reduction in space. Instead, symptoms often arise when the rotator cuff cannot adequately control the humeral head due to weakness, fatigue, or altered neuromuscular control.

Postural adaptations and poor scapular motion can also increase demands on the rotator cuff. For example, reduced upward rotation or posterior tilt of the scapula decreases the effective subacromial space during elevation. Addressing these factors explains why exercise—rather than compression-focused interventions—has become the primary treatment.

Exercise Therapy

Exercise is the cornerstone of treatment. Effective programs typically combine:

• Rotator cuff strengthening, especially external rotation

• Scapular stabilization, focusing on lower trapezius and serratus anterior

• Motor control training, restoring coordinated scapulohumeral rhythm

• Progressive load exposure, matching patient goals and activity demands

• Eccentric and heavy–slow resistance loading, improving tendon resilience

Mild discomfort during exercise is acceptable, provided it does not escalate afterward. Gradual progression is essential.

Manual Therapy

Manual therapy can support rehabilitation by reducing pain and improving mobility in the early stages. Techniques targeting the glenohumeral joint, thoracic spine, and surrounding musculature may help normalize movement. However, long-term outcomes depend on the patient’s active participation in strengthening and retraining rather than passive modalities.

Medications and Injections

NSAIDs and analgesics may help in the short term but should not be relied upon as primary treatment. Subacromial corticosteroid injections can reduce pain temporarily, particularly when bursitis is involved. However, repeated injections may negatively affect tendon quality, making them a supplemental option rather than a central intervention.

Surgical Considerations

Historically, subacromial decompression surgery was frequently performed for impingement. However, multiple large studies have shown that surgery does not outperform conservative care for most patients. Therefore, surgery is reserved for specific cases where rehabilitation has not succeeded and where imaging reveals additional pathology requiring repair.

References

American Academy of Orthopaedic Surgeons. Management of Rotator Cuff Injuries: Clinical Practice Guideline. 2025.

Lewis, J. “Rotator Cuff Related Shoulder Pain: A Modern Clinical Perspective.” British Journal of Sports Medicine, 2018 and updates.

Littlewood, C., et al. “Exercise as a Primary Treatment for Rotator Cuff Related Shoulder Pain.” Journal of Orthopaedic & Sports Physical Therapy, 2015.

Kibler, W., Ludewig, P. “Scapular Dysfunction in Shoulder Injury.” Sports Medicine, 2013.

Reinold, M., et al. “Shoulder Rehabilitation Principles for Overhead Athletes.” Sports Health, 2010 and updates.

Disclaimer

The information in this article is intended for educational purposes and is designed for qualified massage therapists, manual therapists, and rehabilitation professionals. It is not a substitute for medical advice, diagnosis, or treatment. Practitioners must work within their legal scope of practice and regional regulations. Hands-on techniques should only be performed by appropriately trained and licensed individuals. Niel Asher Education is not responsible for any injury, loss, or damage resulting from the use of this content.