In the TFCC load test, which wrist action and loading produce pain if TFCC pathology is present?

• A. Wrist in ulnar deviation; Apply a longitudinal load through the 5th metacarpal bone to the TFCC. Positive is pain
• B. Wrist in radial deviation; Apply a longitudinal load through the 3rd metacarpal; Positive is pain
• C. Neutral wrist; Apply a longitudinal load through the 2nd metacarpal; Positive is pain
• D. Wrist in ulnar deviation; Apply a transverse load through the 4th metacarpal; Positive is pain

Answer: (A)

The test targets the triangular fibrocartilage complex by loading the ulnar side of the wrist and compressing it through the axis of the 5th metacarpal. The TFCC stabilizes the distal radioulnar joint and cushions the ulnocarpal articulation, so placing the wrist in ulnar deviation increases the mechanical load on the ulnar-sided structures. Adding a longitudinal (axial) load through the 5th metacarpal directly transmits force to the TFCC. If there is TFCC pathology, this combination of position and load provokes pain, making the test positive.

Loading the wrist in radial deviation would shift load away from the TFCC toward the radial-sided structures, not optimally stressing the TFCC. A neutral wrist or loading through the 2nd or 3rd metacarpal tends to stress other carpal or radiocarpal structures rather than specifically the TFCC. Similarly, a transverse load through a different metacarpal doesn’t reproduce the same compression pattern on the TFCC.