To measure shoulder internal rotation, which combination is correct for patient position and goniometer setup?

• A. Position: Supine with 90 degrees GHJ abduction; Stabilize: distal humerus to keep 90 degrees abduction and scapula stabilized to prevent anterior tilting; Fulcrum: Over olecranon process; Stationary Arm: parallel or perpendicular to the floor; Moving Arm: aligned with ulna from olecranon to ulnar styloid
• B. Position: Supine with arm by the side; Stabilize: thorax; Fulcrum: lateral epicondyle; Stationary Arm: along spine; Moving Arm: along the radius
• C. Position: Seated; Stabilize: ribcage; Fulcrum: center of the head; Stationary Arm: line between acromions; Moving Arm: forearm
• D. Position: Prone; Stabilize: scapula; Fulcrum: olecranon; Stationary Arm: along ulna; Moving Arm: along radius

Answer: (A)

When measuring shoulder internal rotation, you want to isolate the glenohumeral joint motion and minimize any contribution from the scapulothoracic complex. Placing the shoulder at 90 degrees of abduction with the elbow flexed helps keep the humeral head in the joint while preventing contributions from shoulder elevation or forward tilt. Stabilizing the distal humerus so that the arm remains at 90 degrees of abduction and stabilizing the scapula prevents unwanted movement (like anterior tilting or scapular motion) that would distort the measurement. The goniometer should have its fulcrum right over the olecranon process, the stationary arm perpendicular to the floor, and the moving arm aligned along the ulna from the olecranon toward the ulnar styloid. This setup follows the standard orientation for internal rotation of the shoulder and yields an accurate read of how far the humerus can rotate inward. The other setups either place the limb in a nonabducted position, use an incorrect fulcrum, or misalign the arms in a way that would reflect movements of the scapula, forearm rotation, or other joints rather than pure glenohumeral internal rotation.