Shoulder Impingement Syndrome. Permission Joseph E. Muscolino. Kinesiology - The Skeletal System and Muscle Function, 3ed (Elsevier, 2017).

Six Causes of Shoulder Impingement Syndrome – Part 1

Shoulder impingement syndrome is a condition in which the distal tendon of the supraspinatus and the subacromial bursa become impinged between the head of the humerus and the acromion process of the scapula. Following are the six major causes of shoulder impingement syndrome.

Locked short muscles / locked long muscles in upper crossed syndrome and lower crossed syndrome

Locked Short Muscles – Locked Long Muscles

Two opposing muscle groups, the “facilitated” muscles that are locked short and the “inhibited” muscles that are locked long.