Anatomy of Shoulder Function

The shoulder's functionality relies heavily on the balance between large prime movers and smaller stabilizer muscles. Key muscles such as the latissimus dorsi, pectoralis major, and deltoid, which are responsible for significant movements, attach further down the humerus, providing them with a mechanical advantage during actions like throwing. In contrast, the rotator cuff muscles, which stabilize the shoulder, connect closer to the humeral head, functioning like a seesaw that counters the force exerted by the larger muscles. This intricate relationship is especially crucial during the acceleration phase of throwing, where improper rotation can lead to instability and potential injury.