Example Video Analysis

The lower trapezius is an important shoulder stabilizer. When the lower trapezius is weak, the body will search for other muscle groups to help raise the arm overhead. Since the person in the video has a weak lower trapezius muscle, he has resorted to using his obliques and quadratus lumborum (a trunk muscle) to assist with the movement. As he raises his arm, he activates the left external obliques, which causes trunk rotation to the right. 

The inability to raise the arm when positioned overhead is often due to poor scapular (shoulder blade) strength, specifically the lower trapezius muscle. The lower trapezius is an important shoulder stabilizer. When not working properly, individuals often have shoulder or neck pain. This muscle is frequently weak in people with shoulder problems due to the forward head, rounded shoulders posture seen across the population.

To raise the arm overhead, a person needs to have adequate thoracic extension and rotation range of motion. People with an increased thoracic kyphosis have difficulty reaching overhead and often report pain in the anterior (front) shoulder. Try this on yourself now! Sit in a slouched position and attempt to raise the arm overhead- it will likely be limited and potentially painful. 

Interview Series

Connecting with Movement Specialists

The Movement Corner connects you with TOP movement experts. The interview series delves into movement assessment, pain management, treating patients, and life skills. 

Enjoy this short clip from the interview with Dr. Ryan DeBell.