This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Orthopaedics
Which carpal bone fracture causes median nerve involvement? 
Select and explain. 
A. Scaphoid, B. Lunate, C. Trapezium, D. Trapeziod
B: Lunate
Answer: B: Lunate 
Explanation: A palmar pole fracture of lunate may cause carpal tunnel syndrome and median nerve compression.