The elbow joint is a biomechanically complex articulation within the functional chain of the upper extremity, as it must simultaneously provide high stability and a wide range of motion. Elbow stability is achieved through a delicate interplay between osseous congruency, capsuloligamentous structures, and dynamic muscular stabilizers. Disruption of this balance may lead to a broad spectrum of instability, ranging clinically from mild apprehension and a subjective sense of insecurity to recurrent subluxations and dislocations, pain, and advanced functional impairment. The most common etiologies of elbow instability include acute traumatic dislocations and fracture-dislocations, repetitive microtrauma (particularly in overhead throwing athletes), iatrogenic ligamentous injuries, and inadequately treated ligamentous lesions. Surgical management constitutes the main treatment option for patients with structural instability and significant functional limitation who fail to respond to conservative measures. Contemporary surgical strategies emphasize that elbow instability should not be regarded as an isolated ligament injury; rather, it should be approached as a pattern-based pathology requiring a comprehensive evaluation of both osseous and soft-tissue components. In this review, the anatomical and biomechanical foundations of elbow instability, its pathophysiology and classification, clinical assessment and diagnostic work-up, surgical indications and techniques, adjunctive stabilization methods, postoperative rehabilitation, clinical outcomes, complications, and current controversies are discussed comprehensively in light of the available literature.