22
Evaluation and Treatment of Rotator Cuff Impairments: Summary
Rotational Motions Unlike translational movements, rotational movements change the scapula’s orientation as it pivots around a point. These rotations are important for maintaining balance and alignment during more complex shoulder movements, such as raising or lowering the arm. Upward rotation : When the lateral edge of the scapula tilts upward, it’s called upward rotation. This is the movement that occurs when you raise your arm overhead. Without upward rotation, the arm wouldn’t have the clearance it needs. The upper trapezius, lower trapezius, and serratus anterior work together to create this motion, keeping the shoulder joint in alignment and protecting it from impingement. Downward rotation : Downward rotation occurs as the arm lowers from an elevated position. Muscles like the levator scapula, rhomboids, and pectoralis minor guide the scapula back to its resting position to ensure smooth arm movement. Upward and downward rotation are defined by the tilt of the acromion process. LEARNING TIP! The acromion process, which acts
EVIDENCE-BASED PRACTICE Standing in anatomical position, the scapula is naturally oriented slightly upward and forward, around 30 to 35 degrees anterior to the frontal plan, a position that supports optimal shoulder function and helps prevent issues like impingement . To become more aware of the movement mechanics in the shoulder girdle, particularly how the clavicle and scapula contribute to shoulder mobility, try the following exercise: 1. Put your right index finger on your left clavicle. 2. Slowly move your left arm into shoulder flexion. 3. Can you feel the clavicle moving? 4. Locate the acromion process. 5. Abduct your humerus. 6. Can you feel the scapula rotating THE ROTATOR CUFF The rotator cuff is a group of four muscles, the supraspinatus, infraspinatus, teres minor, and subscapularis, that are essential for stabilizing the shoulder joint. They work together to keep the humeral head centered in the coracoacromial arch during movement. Without this stabilization, the shoulder would be at risk for dislocation or impingement . Supraspinatus The supraspinatus is a relatively small muscle that is crucial for initiating arm abduction, handling the first 15 degrees before the deltoid takes over. Located at the top of the scapula, it is often vulnerable to injury due to its position under the acromion, where impingement can easily occur if shoulder mechanics are off.
as the “peak” of the scapula, helps determine which way the scapula is rotating. This rotational motion is crucial for maintaining proper alignment of the humerus and scapula, which prevents impingement as well as decreased strength and range of motion, and it keeps the shoulder functioning properly.
Translational and rotational movements work in harmony to keep the shoulder joint stable and functioning efficiently. For instance, when you raise your arm, the scapula not only rotates upward but also elevates and protracts slightly, allowing for full range of motion.
Powered by FlippingBook