The terrible triad of the elbow is already a complex injury, but associated injuries to the ipsilateral upper limb can be missed because pain, swelling and restricted motion limit the initial examination. This systematic review examined additional osseous, ligamentous, chondral and soft-tissue injuries reported alongside terrible triad patterns. The review identified a range of concomitant injuries, with olecranon fractures among the more frequently reported associations. The clinical significance is that a focused elbow diagnosis is not enough: clinicians should assess the entire limb, especially when the trauma mechanism or imaging suggests additional pathology. The paper also reinforces the importance of advanced imaging and careful radiographic review when the examination is limited. From a surgical perspective, identifying associated injuries preoperatively can change the treatment plan, influence positioning and prevent unexpected instability or functional deficits after surgery. The evidence base consists largely of case reports and small series, so the exact frequency of additional injuries remains uncertain. Nevertheless, the principle is highly practical: in severe elbow trauma, a surgeon should actively look for injuries beyond the three classic components of the terrible triad. Better recognition can translate directly into safer planning and fewer missed diagnoses.