## **Core Concept**
A Colles' fracture is a type of fracture that occurs at the distal end of the radius bone in the forearm, typically resulting from a fall onto an outstretched hand. The fracture is characterized by the displacement of the distal fragment of the radius.

## **Why the Correct Answer is Right**
In a Colles' fracture, the distal fragment of the radius is typically displaced posteriorly (dorsally), resulting in a characteristic "dinner fork" deformity of the wrist. This posterior displacement is due to the force of the fall causing the distal radius to fracture and then displace posteriorly.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option might suggest an incorrect direction or type of displacement, which could be anterior (palmar) displacement. However, in a Colles' fracture, the displacement is typically posterior (dorsal), not anterior.
- **Option B:** This option could suggest a different type of fracture or displacement that does not accurately describe the typical Colles' fracture displacement.
- **Option C:** This option is not provided, but if it suggested a displacement in a different direction or a different fracture characteristic, it would be incorrect based on the typical presentation of a Colles' fracture.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl for Colles' fractures is that they are often associated with a "dinner fork" deformity of the wrist due to the posterior displacement of the distal fragment of the radius. This deformity is a classic sign that helps in the clinical diagnosis of a Colles' fracture.

## **Correct Answer:** . Posteriorly.