A Rolando fracture is a comminuted intra-articular fracture-dislocation of the base of the thumb (base of the 1st metacarpal). Simply put, it is a comminuted Bennett fracture. The mechanism is usually an axial blow to a partially flexed metacarpal, such as in a fistfight. The fracture line is typically T or Y-shaped. The volar fragment remains attached to the carpometacarpal joint, while the main dorsal fragment subluxes or dislocates dorsally and radially due to the unopposed pull of the abductor pollicis longus.

This is an unstable injury that requires surgical reduction and fixation.