Irreducible Anterior Shoulder Dislocation Caused by Soft Tissue Interposition: A Comprehensive Review.

Anterior shoulder dislocation is the most common type of joint dislocation encountered in clinical practice, with the vast majority being successfully managed using closed reduction techniques. However, in rare instances, anatomical obstacles prevent successful closed reduction, necessitating open surgical intervention. Irreducible anterior shoulder dislocations caused by soft tissue interposition represent a challenging clinical entity that requires prompt recognition and appropriate management. This comprehensive review examines the pathophysiology, clinical presentation, diagnostic approaches, and treatment strategies for irreducible anterior shoulder dislocations secondary to soft tissue interposition, with an emphasis on recent literature from 2008 to 2025. The most commonly interposed structures include the long head of the biceps tendon (LHBT), the subscapularis tendon, other rotator cuff components, and, rarely, peripheral nerves. Understanding the mechanisms of irreducibility, recognizing clinical red flags, and implementing appropriate imaging protocols are essential for optimal patient outcomes. The deltopectoral approach remains the standard surgical access, with external rotation maneuvers facilitating the delivery of interposed subscapularis tissue. MRI provides superior soft tissue characterization compared to CT when plain radiographs fail to demonstrate obvious bony pathology. Outcomes are generally favorable when early recognition is coupled with appropriate surgical intervention and structured rehabilitation, although complications, including nerve injury and residual functional deficits, can occur.