What type of fracture occurs at the distal aspect of the radius, typically from wrist extension and radial deviation?

A Colles fracture is characterized by a fracture at the distal end of the radius, typically resulting from a fall onto an outstretched hand, particularly with wrist extension and radial deviation. This injury is common among older adults, especially in the context of osteoporosis. The distinct feature of a Colles fracture is the dorsal angulation and often dorsal displacement of the distal fragment, which results in a characteristic "dinner fork" or "bayonet" appearance of the wrist when assessed clinically.

In the context of the other fracture types mentioned, a Smith fracture arises from wrist flexion and is distinguished by palmar angulation of the distal fragment. A Greenstick fracture is a type of incomplete fracture often seen in children, where the bone bends and partially breaks on one side. A Navicular fracture generally refers to injuries to the scaphoid bone in the wrist and is associated with specific mechanisms of injury, not typically linked to wrist extension and radial deviation.

Understanding these distinctions is crucial when assessing injuries to the wrist and determining the appropriate treatment and care.