After falling on the pavement, a 72-year-old woman is found to have a fracture of the radius and ulna (Colles' fracture). What is true of this fracture?

The distal radial metaphysis is displaced dorsally. This fracture was described by Colles over 150 years ago. The impact is caused by a fall on the flexor surface of the wrist. The distal segment is displaced dorsally. The reverse injury, involving a fall on the extensor surface of the wrist and flexor deformity, is a Smith fracture. Colles fracture occurs more commonly in older women. The styloid of the ulna not the shaft of this bone is fractured.