What is Subacromial Impingement?

The diagnosis of impingement is an umbrella term to describe the mechanism of shoulder pain that stems from the structures under the subacromial arch and coracohumeral ligament. It’s a broad term. Some clinicians feel that it’s a junk term. It does not specifically identify the painful structure(s). It’s kinda in the same ballpark as “mechanical back pain.” The truth is, for both conditions - shoulder impingement and mechanical back pain - we don’t really know 100% the true source of pain.1 However, like mechanical low back pain, subacromial impingement can definitely direct the patients’ conservative and surgical management strategy.