**Core Concept**
Barton's fracture is a type of intra-articular fracture of the distal radius, characterized by an intra-articular fracture of the distal radius with a dislocation of the radiocarpal joint. This fracture involves the radiocarpal joint, which is the joint between the distal radius and the carpal bones of the wrist.

**Why the Correct Answer is Right**
Barton's fracture occurs when there is a dislocation of the radiocarpal joint with an intra-articular fracture of the distal radius. This type of fracture is often caused by a fall onto an outstretched hand, resulting in a combination of a fracture and a dislocation. The fracture involves the articular surface of the distal radius, which is the part of the bone that articulates with the carpal bones. This results in a disruption of the radiocarpal joint and a potential for long-term damage to the wrist joint.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe Barton's fracture, which involves a dislocation of the radiocarpal joint.
**Option B:** This option is incorrect because it describes a different type of fracture, such as a Colles' fracture, which is a fracture of the distal radius without a dislocation of the radiocarpal joint.
**Option C:** This option is incorrect because it does not accurately describe Barton's fracture, which involves a dislocation of the radiocarpal joint.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that Barton's fracture is a type of intra-articular fracture that requires prompt and accurate diagnosis and treatment to prevent long-term damage to the wrist joint. A high index of suspicion is necessary for diagnosing this fracture, particularly in patients who present with a history of a fall onto an outstretched hand.

**Correct Answer: C. A fracture of the distal radius with a dislocation of the radiocarpal joint.**