In sidelying, which pillow placement helps prevent shoulder protraction/internal rotation and brachial plexus stretch?

• A. Behind back: prevents rolling backward
• B. Under top arm: prevent shoulder protraction/internal rotation, reduce brachial plexus stretch
• C. Between knees: prevent hip adduction
• D. Under head: fill space between head/mattress, maintain neutral cervical spine

Answer: (B)

In sidelying, the goal is to keep the top shoulder in a neutral position so it doesn’t protract or rotate inward, which can lengthen the brachial plexus. Placing a pillow under the top arm provides direct support to the arm and shoulder girdle, helping the humerus stay in a more neutral/external-rotated posture. This prevents the shoulder from sliding forward and keeps the scapula in a stable position, reducing tension along the brachial plexus and improving comfort for the upper body.

Other placements don’t address shoulder alignment as effectively: a pillow behind the back mainly stops backward rolling but doesn’t prevent shoulder protraction; a pillow between the knees targets hip alignment; a pillow under the head maintains the neck position but doesn’t influence the shoulder girdle.