There are several causes to SIS including:
- Repetitive overhead movements, such as golfing, throwing, racquet sports, and swimming, or frequent overhead reaching or lifting.
- Injury, such as a fall, where the shoulder gets compressed.
- Bony abnormalities of the acromion (tip of the scapula), which narrow the subacromial space.
- Osteoarthritis in the shoulder region.
- Poor rotator cuff and shoulder blade muscle strength, causing the humeral head to move abnormally.
- Thickening of the bursa.
- Thickening of the ligaments in the area.
- Tightness of the soft tissue around the shoulder joint called the joint capsule.
The mainstay of conservative treatment for SIS involves therapeutic exercises to restore normal flexibility and strength to the shoulder girdle. Supervised therapeutic exercise has been proven more superior to home exercise for SIS. Manual therapy combined with supervised therapeutic exercise has proven to be significantly more effective than supervised therapeutic exercise alone.
In 2000 Bang and Deyle compared manual therapy and exercise to exercise only in a group of patients with SIS. The two groups received 7 sessions over 3 weeks and were followed for 1 year. The manual therapy group reported 70% less pain, 35% improvement in function, and 16% increase in isometric shoulder strength. In contrast the exercise only group reported 35% less pain, 17% improvement in function, and no significant improvement in shoulder strength.
So if you want twice the pain relief and improved shoulder strength go see your local PT with orthopaedic specialty credentials and receive an individualized exercise program and manual therapy techniques to address your shoulder problem.
Bang, M., & Deyle, G. (2000). Comparison of supervised exercise with and without manual physical therapy for patients with shoulder impingement syndrome. Journal of Orthopaedic & Sports Physical Therapy, 30(3), 126-137.
APTA. (2015). Physical therapist's guide to shoulder impingement.