A patient presents with severe pain in the flexor muscles of the forearm, fixed flexion of the fingers, swelling, cyanosis, and anesthesia. Which of the following fractures is the most likely precipit

The correct answer is A. Colles' fracture.

• The symptoms described—severe pain in the flexor muscles of the forearm, fixed flexion position of the fingers, swelling, cyanosis, and anesthesia of the fingers—are classic signs of acute compartment syndrome of the forearm. If left untreated, this can lead to Volkmann's ischemic contracture, characterized by fixed flexion deformities.
• Acute compartment syndrome occurs when increased pressure within a confined fascial compartment compromises circulation and nerve function.
• Among the given options, a Colles' fracture (a fracture of the distal radius) is a common traumatic injury to the forearm that can lead to significant swelling and hemorrhage, thereby precipitating acute compartment syndrome. The other fractures listed (scaphoid and Bennett's) are less likely to cause such widespread and severe symptoms affecting the entire forearm flexor compartment and hand.