A 28-year-old construction worker presents to the emergency department with severe wrist pain and swelling after a fall on an outstretched hand with the wrist in hyperextension. Lateral X-ray of the wrist shows the structure marked **B** displaced volar (palmar) to its normal anatomic position, while the radius and remaining carpal bones remain aligned. The radiologist notes a "spilled teacup" appearance on the lateral view. Which of the following is the most appropriate immediate management?

Explanation

## Why option 1 is correct The structure marked **B** is the lunate. Volar dislocation of the lunate with the "spilled teacup sign" on lateral X-ray is the hallmark of lunate dislocation — the most severe carpal dislocation. This is a high-energy injury requiring emergency closed reduction with longitudinal traction and direct pressure on the lunate to restore alignment, followed by urgent orthopedic consultation for open reduction, scapholunate ligament repair, and temporary pinning. Immediate intervention is critical to prevent acute carpal tunnel syndrome (from median nerve compression) and long-term avascular necrosis (Kienböck disease). ## Why each distractor is wrong - **Option 2**: Thumb spica immobilization and delayed imaging is appropriate for scaphoid fractures (the most common carpal injury), not lunate dislocation. Lunate dislocation is a true orthopedic emergency requiring immediate reduction, not conservative management. - **Option 3**: While orthopedic consultation is urgent, closed reduction should be attempted first as the initial step. Open reduction is reserved for cases where closed reduction fails or for definitive ligament repair after initial reduction. - **Option 4**: Lunate dislocation does not reduce spontaneously and requires active intervention. Delaying reduction increases the risk of median nerve compression and avascular necrosis of the lunate. **High-Yield:** Lunate dislocation (volar displacement, "spilled teacup" on lateral X-ray) is a true orthopedic emergency requiring immediate closed reduction followed by open reduction and ligament repair; distinguish from perilunate dislocation ("empty teacup") where the lunate stays in place but the rest of the carpus dislocates dorsally. [cite: Gray's Anatomy 42e Ch 49; Apley 10e]