The Terrible Triad of the Elbow: A Narrative Review of Anatomy, Biomechanics, Classification, and Surgical Management

Abstract

The terrible triad of the elbow posterior elbow dislocation combined with fractures of the radial head and coronoid process is among the most unstable and historically challenging patterns of upper-extremity trauma. This review summarizes the applied anatomy and biomechanics of elbow stability, the classification systems used to describe coronoid and radial head fractures, the principles of clinical and radiological evaluation, and the evolution of surgical management from nonoperative care to structured, sequential fixation of the coronoid, radial head, and lateral collateral ligament complex. Current evidence on surgical approach selection lateral-only versus combined lateral-and-medial strategies remains genuinely mixed: the largest available network meta-analysis and several pairwise comparisons suggest combined approaches may achieve superior range of motion and functional scores, while lateral-only approaches carry a substantially lower risk of iatrogenic ulnar nerve injury. We summarize this evidence, alongside data on coronoid-fixation thresholds, postoperative rehabilitation, and complication rates, to provide a current, evidence-based overview for clinicians managing this injury.