This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Avascular Necrosis, Subject name: Orthopaedics
Most common complication of scaphoid fracture- 
Select and explain. 
A. Malunion, B. Avascular necrosis of proximal part, C. Wriststiffners, D. Arthritis
B: Avascular necrosis of proximal part
Answer: B: Avascular necrosis of proximal part 
Explanation: Ans. is 'b' i.e., Avascular necrosis Complication of scaphoid fracture o Fractures of the scaphoid bone, even when undisplaced, are potentially troublesome and the incidence of complications is high, o The most important complications are :- Delayed union Non-union Avascular necrosis Osteoarthritis of wrist "AVN is the most common complication of a scaphoid fracture, occuring in 15% to 30% of cases". o Risk of AVN depends on the location of the fracture :- Fracture of the proximal segment (proximal 1/3) has the highest risk Fracture of middle segment (waist) has moderate risk Fracture of distal segment rarely causes AVN o The proximal part is more susceptible for AVN because of retrograde vascular supply. Most of the blood supply to the scaphoid enters distally, and proximal part has precarious supply after fracture through waist or proximal part of the bone. o Therefore, AVN occurs in proximal part.