The aim of this retrospective study was to evaluate the medium-term clinical and functional outcomes of patients with closed, displaced, and unstable, simple or complex, intra- and extra-articular distal radius fractures (DRFs) treated with a bridging external fixator (BEF) and optional K-wires (KWs). AO classification was used to differentiate the injuries radiographically. Clinical-functional outcomes were evaluated using the Patient-Rated Wrist and Hand Evaluation Score (PRWHE Score) and the Quick Disabilities of the Arm Shoulder and Hand Score (QuickDASH). A total of 269 dorsally displaced fractures of 202 female (75%) and 67 male subjects (25%) were included, with a mean follow-up of 58.0 months. Seventy-five patients (28%) were treated by additional KWs. No differences were found comparing the two groups of patients (BEF vs. BEF + KWs) regarding age, sex, and fracture side (dominant vs. non-dominant). PRWHE and QuickDASH scores were lower in the BEF + KWs group compared to the BEF group (p < 0.0001 and p = 0.0007, respectively). Thus, patients treated with KWs had a better clinical outcome. Beta multivariate regression analysis confirmed that patients of the BEF + KWs group exhibited a better PRWHE score but not a better QuickDASH score. Patients treated by the BEF + KWs with the fracture on the dominant site were characterised by better clinical outcomes. Older patients had a better PRWHE score independently from the treatment. Our findings suggest that the use of BEF for DRFs with optional KWs can be indicated in both young and elderly patients of any gender, independent of limb side and fracture pattern. As the best functional results were achieved in the elderly when KWs were added, the combination of BEF and KWs seems to be mainly indicated for the treatment of DRF, also complex, in the elderly population.