Which of the following is a cause of scapular winging?

Scapular winging occurs when the scapula is not properly stabilized against the rib cage, resulting in a protrusion or "winging" of the scapula away from the thorax. One of the primary causes of this condition is poor eccentric control of the scapulothoracic region. Eccentric control refers to the ability of muscles to lengthen while producing tension, which is crucial for maintaining stability during movement.

When there is poor eccentric control, the muscles that stabilize the scapula—mainly the serratus anterior, trapezius, and rhomboids—struggle to perform their functions effectively. This can lead to improper movement patterns and inadequate stabilization of the scapula during shoulder motions, contributing to winging.

Identifying this cause allows for targeted corrective strategies, focusing on strengthening and improving the coordination of the stabilizing muscles, which can help restore proper scapular function and alleviate winging. Other options may relate to shoulder mechanics and muscle balance, but they do not directly pinpoint the eccentric control aspect, which is crucial for maintaining scapular stability.