Subacromial Impingement Syndrome
What is the Subacromial Space?
The shoulder girdle is made up of the connection between three bones: the scapula (the shoulder blade), the clavicle (the collarbone), and the humerus (the upper arm bone). The space in between the top of the humerus and the “roof” of the scapula is known as the subacromial space. Inside this space run the tendons of muscles such as the biceps brachii and the rotator cuff muscles along with a fluid filled sac known as a bursa1.
What is impingement?
Impingement is often described as the start of a continuum, which can eventually lead to tendon breakdown followed by partial and full tears of the tendon. This occurs when one of the structures that run through the subacromial space (often one of the tendons) gets pinched by the surrounding bone during movement. Impingement is characterized by a “painful arc” where one feels pain partway through a movement - generally halfway through the full range - with no pain at the start or end of the full range. A painful arc is usually experienced in flexion (bringing the arms straight forward) and abduction (bringing the arms out to the side) of the shoulder.
Impingement is often caused by repetitive overhead work. Factors such as abnormal biomechanics and muscle imbalances within the shoulder can contribute to impingement syndrome. Impingement can also occur as a result of instability of the shoulder joint, or from a tight joint capsule which can lead to abnormal shoulder mechanics.
Who is at risk of developing impingement?
Repetitive overhead work is a big risk factor for developing impingement, along with the anatomical factors discussed above. In addition genetic factors such as differently shaped bones may also lead to an increased risk of developing impingement.
What can physiotherapy do for impingement?
Since shoulder biomechanics play such a large role in the development of impingement, physiotherapy has been found to be a very effective treatment1! Physiotherapists can work to control the pain and inflammation that is present early on in impingement. Afterwards, physiotherapy treatment aims to restore proper shoulder position and biomechanics in order to help you return to your normal functional self. This can be done in ways such as:
Motor control exercises
Contact us for more information on what physiotherapy can do for your sore shoulder!
Josh Chung, UWO PT Student
Dickens VA., et al. 2005. Role of physiotherapy in the treatment of subacromial impingement syndrome: a prospective study. Physiotherapy. 91:159-64
Lewis JS., et al. 2005. Subacromial impingement syndrome: the role of posture and muscle imbalance. J Shoulder Elbow Surg. 14(4):385-92.
Kuhn JE. 2009. Exercise in the treatment of rotator cuff impingement: A systematic review and a synthesized evidence-based rehabilitation protocol. J Shoulder Elbow Surg. 18:138-60.
Sauers EL. 2005. Effectiveness of Rehabilitation for Patients with Subacromial Impingement Syndrome. Journal of Athletic Training. 40(3):221-3.