We report the case of a 72-year-old woman in whom a mega wrist prosthesis was used to reconstruct the distal radius after en-bloc resection of a giant cell tumour. Three years later, her pain score was 2/10 and motion ranges were 20° of flexion, 70° of extension, 70° of pronation, 60° of supination, 20° of radial deviation, and 20° of ulnar deviation. The QuickDASH score was 52.27/100 and the Enneking score was 83%. Radiographically, the prosthesis was well aligned, with no evidence of loosening but with dorsal subluxation of the ulnar head. The outcome in this patient, together with published data, indicate that mega prosthesis use is among the treatment options for distal radius reconstruction after en-bloc resection of a giant cell tumour, provided a biocompatible, bipolar, unconstrained prosthesis is used.