Amongst people with shoulder pain, shoulder impingement syndrome (SIS) is the most common, accounting for 36% of all shoulder disorders.
SIS is an overarching term for injury to the structures in the subacromial space affecting the rotator cuff tendons and bursa. Commonly related pathologies include rotator cuff tendinosis, partial tears of the rotator cuff muscles, and bursitis. However, it is still unclear as to whether these conditions cause physical compression of the structures that result in symptoms.
Symptoms
Common symptoms include pain and weakness especially with overhead activities. Pain at the shoulder joint usually presents at the front or outside causing restrictions to movement typically between 70° and 120°, pain on forced movements above head and inability to sleep on the affected side.
Causes
Possible causes of subacromial space narrowing and shoulder impingement include:
Trauma to the shoulder resulting in inflammation of the subacromial space
Bony spurs or irregular shape of the acromion
Thickening or calcification of the internal ligaments (such as the coracoacromial ligament)
Poor mechanics of the shoulder due to weakness of the shoulder stabilising muscles and poor scapula movement
Management
Good results can be seen in approximately 80% of cases, with either conservative or surgical management. In the absence of severe structural damage, conservative management is preferred initially, lasting over 3 - 6 months. However, approximately 30% of patients will undergo surgery due to ineffective conservative treatments.
Conservative management usually involves a combination of treatments such as immobilisation, exercise, manual therapy and acupuncture. Exercise in particularly is used to facilitate the rehab process, and allows an individual to self-manage their condition in between physiotherapy reviews.
An example of the recovery process is as follows:
Initial management usually involves rest from the aggravating activities at first, and trying to settle the irritated tissue and reduce pain, while maintaining as much function as possible.
Stretching and other treatments are used to address any tightness in the shoulder capsule that may be limiting movement.
Once the acute symptoms have improved, and full movement of the shoulder is restored, rehabilitation is focused on exercises to strengthen the shoulder.
Conditioning the shoulder so that it has good endurance and overall fitness to cope with activities.
Functional retraining for returning to work or sport, focusing on commonly required movements.
References
Garving, C., Jakob, S., Bauer, I., Nadjar, R., & Brunner, U. H. (2017). Impingement syndrome of the shoulder. Deutsches Ärzteblatt International, 114(45), 765.
Koester, M. C., George, M. S., & Kuhn, J. E. (2005). Shoulder impingement syndrome. The American journal of medicine, 118(5), 452-455.
Images obtained from physio-pedia.com