What Is It?
Shoulder impingement can be a pain during various movements of your involved shoulder. Let me first explain some of the anatomy of the shoulder complex:
Humeral head--this is the top part of your upper arm bone that helps form the ball-and-socket joint of the shoulder, which should stay centered in the socket
Acromion, coracoid, and coracoacromial ligament--these sit above the humeral head and form what we call the ‘subacromial space’
Supraspinatus tendon (one of the rotator cuff muscles), long head of biceps tendon, and bursa--these structures all reside in the ‘subacromial space’
When does impingement occur?
Mainly when the rotator cuff muscles and the scapular muscles are NOT holding the humeral head in its proper place (centered in the socket).
So, what ends up happening typically is the head of the humerus begins to translate upward (superiorly) and the contents listed above in that subacromial space become impinged/pinched against one or more of the structures above that space. This can then lead to pain with certain ranges of movement or activities.
Types of Impingement:
Impingement by the coracoacromial arch
Primary: bony problem--often due to the shape of an individual’s acromion
Secondary: anterior and/or superior migration of the humeral head due to weakness or muscle imbalance of rotator cuff/scapular muscles
Do You Have Shoulder Impingement?
Best combination of tests to rule in subacromial impingement syndrome:
Hawkins-Kennedy Impingement Test
Painful arc sign
Infraspinatus muscle test
*Park and colleagues found that if 2 out of the 3 of these tests were positive then there was a 98% chance these individuals had subacromial impingement syndrome
What Can You Do About It?
A full assessment by a physical therapist can help you determine the appropriate exercise plan for you and your individual impairments/limitations as there are numerous things that need to be assessed that can influence shoulder pain/impingement.
Shoulder blade (scapula) movement
Dysfunctions can be related to: muscle timing issues, force couple imbalances, weakness, length issues
Shoulder blade positioning
Upper trap vs lower trap muscle activity during overhead movements
Position of our ribcage/rib mobility
Mid back/thoracic spine mobility (extension)
So, if you think you may have shoulder impingement or pain that is limiting you from doing certain activities during your day to day, contact a physical therapist and schedule an evaluation!! You won’t regret it! It’s time to start living pain-free :)
Kaitlin Hartley, PT, DPT
Ludewig PM, Braman JP. Shoulder impingement: Biomechanical considerations in rehabilitation. Manual therapy. 2011; 16 (1): 33-39.
Culham E, Peat M. Functional anatomy of the shoulder complex. Journal of Orthopaedic and Sports Physical Therapy. 1993; 18: 342-350.
Hegedus EJ, Cook C, Lewis J, Wright A, Park J. Combining orthopedic special tests to improve diagnosis of shoulder pathology. Physical Therapy in Sport. 2015; 16 (2): 87-92.