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.