Which arrangement correctly describes wrist flexion/extension measurement, including patient position and goniometer placement?

• A. Position: Supine with 90 degree GHJ abduction and 90 degree elbow flexion; Stabilize: Radius and ulna to prevent supination or pronation; Fulcrum: lateral aspect of wrist over the triquetrum; Stationary Arm: lateral midline of ulna, using olecranon and ulnar styloid process for ref; Moving Arm: lateral midline of 5th metacarpal
• B. Position: Supine; Stabilize: forearm; Fulcrum: radial styloid; Stationary Arm: along ulna; Moving Arm: along metacarpals
• C. Position: Sitting; Stabilize: elbow; Fulcrum: center of the wrist; Stationary Arm: along the ulna; Moving Arm: along the hand
• D. Position: Prone; Stabilize: radius; Fulcrum: capitate; Stationary Arm: along the radius; Moving Arm: along the metacarpals

Answer: (A)

When measuring wrist flexion and extension with a goniometer, you want to isolate the wrist joint and use consistent landmarks for the axis, the stationary arm, and the moving arm. The axis (fulcrum) should be placed over the triquetrum, the stationary arm should run along the ulna with reference points at the olecranon and ulnar styloid, and the moving arm should point along the long axis of the fifth metacarpal. This setup keeps the forearm stable and allows the measurement to reflect pure wrist motion rather than movement at the forearm or elbow.

The described arrangement achieves this: the patient is positioned with the forearm supported and the elbow flexed about 90 degrees, and the radius and ulna are stabilized to prevent rotation of the forearm. The fulcrum is at the lateral aspect of the wrist over the triquetrum, the stationary arm follows the ulna using the olecranon and ulnar styloid as references, and the moving arm tracks along the long axis of the fifth metacarpal. This combination provides an accurate read of wrist flexion and extension.

Why the other setups aren’t appropriate: placing the axis at the radial styloid or at the center of the wrist shifts the reference away from the primary wrist joint involved in flexion/extension. Stabilizing the elbow or using stabilization focused on the radius alone doesn’t reliably prevent forearm rotation, and using a prone position or a capitate-based fulcrum isn’t aligned with standard wrist flexion/extension goniometry.