While a Bennett’s fracture involves a single, discrete intra-articular fracture line at the base of the first metacarpal, a Rolando fracture is strictly defined by what distinct, severe radiographic morphological feature at the exact same anatomical location?

Explanation:
The correct option is d. Described by Silvio Rolando in 1910, the Rolando fracture is a significantly more severe and complex injury than a Bennett's fracture. It is defined as a comminuted intra-articular fracture at the base of the first metacarpal, historically described as having three main fragments producing a distinct 'Y' or 'T' shape on radiographs. Because of the comminution and joint surface destruction, it carries a much poorer prognosis and a higher rate of post-traumatic thumb osteoarthritis, often requiring extensive open reduction and internal fixation or external fixation. Reference: Green's Operative Hand Surgery. Important orthopaedic mcq.