Giant cell tumor of the distal radius is a rare, locally destructive, and frequently recurrent tumor. We present a case of Campanacci Grade III giant cell tumor of the distal radius with pathologic fracture and cortical destruction which was treated with neoadjuvant denosumab. This facilitated en-bloc resection of the entire distal radius, including the articular surface, while minimizing tumor contamination. Reconstruction was accomplished using a vascularized ulnar transposition flap to facilitate radioulnoscapholunate fusion, which was fixated using a long-stem contralateral variable angle locking volar distal radius plate in a dorsal position. This case illustrates multidisciplinary management of a challenging reconstructive problem and demonstrates a novel strategy for fixation which repurposes familiar and readily available hardware to provide optimal osteosynthesis.