Traumatic anterior glenohumeral subluxations comprise the majority of glenohumeral instability events and are endemic in young athletes. Unlike the definitive complete dislocation event, subluxation events may often be more subtle in presentation and, therefore, may be overlooked by clinicians. Glenohumeral subluxation events are associated with a high rate of labral tears as well as humeral head defects. While less is known of the natural history of these injuries, young athletes are at risk for recurrent instability events if not properly diagnosed and treated. While reports of surgical treatment outcomes isolated to subluxation events are limited, arthroscopic and open Bankart repair have been shown to result in excellent outcomes. The purpose of this paper is to review the etiology and pathoanatomy of traumatic anterior glenohumeral subluxations as well as to review the appropriate evaluation and management of patients with this injury.
Keywords: subluxation; glenohumeral subluxation; shoulder instability; instabilityThe glenohumeral joint has the greatest range of motion of any joint in the body, leaving it susceptible to instability, particularly during extremes in ranges of motion, such as those encountered among contact athletes.24 Glenohumeral instability comprises a spectrum of injuries that range from atraumatic subluxations to traumatic dislocations. Although glenohumeral subluxation accounts for the majority of shoulder instability events, studies that have investigated shoulder instability have focused primarily on glenohumeral dislocations. 21,26 Glenohumeral subluxation events are more difficult to investigate because of the challenge of precisely defining and diagnosing these events.
27In 1980, Protzman 29 clearly delineated glenohumeral subluxation as a unique type of shoulder instability that is present in shoulders that have not previously sustained a glenohumeral dislocation event. In 1983, Warren 37 reported on a series of patients with chronic recurrent glenohumeral subluxations who underwent a stabilization procedure. Radiographic evaluation of these patients revealed that 37% of patients had a Hill-Sachs lesion and 50% had a Bankart lesion. In 1983, Mizuno and Hirohata 21 also reported on a series of 55 patients with chronic recurrent anterior glenohumeral subluxations. They reported that radiographs demonstrated a Bankart lesion in 45 of these patients. In 1992, Burkhead and Rockwood 4 reported on a series of patients with traumatic glenohumeral subluxation, and 55% of these patients had radiographic evidence of an osseous Bankart lesion. In 2007, Owens et al 26 demonstrated that 85% of traumatic glenohumeral instability events are glenohumeral subluxations rather than dislocations. These were diagnosed by a history of a traumatic shoulder event combined with physical examination findings of a positive anterior apprehension sign and a symptomatic load shift. Despite long-term knowledge of glenohumeral subluxations and the subsequent studies that demonstrated a high rate of associated gl...