Is external rotation the correct immobilisation for acute shoulder dislocation? An MRI study

Abstract

Level IV. Retrospective therapeutic study.

Anterior shoulder instability: a review of pathoanatomy, diagnosis and treatment

“…Placing the arm in 30°of external rotation compresses the subscapularis against the anterior glenoid neck. In doing so, it reduces the anterior joint effusion as well as the separation and displacement of the anterior labrum [31,32]. In their preliminary study, Itoi et al [30] equally assigned 40 patients to either conventional sling immobilization or immobilization in external rotation after their initial anterior shoulder dislocation.…”

Effectiveness of External-Rotation Immobilization After Initial Shoulder Dislocation in Reducing Recurrence Rates

“…Itoi et al 13 and others [14][15][16] have demonstrated better coaptation of the labrum onto the glenoid in ER than IR, allowing for more optimal healing. The ability to reduce displacement and separation of the labrum from the glenoid in ER promotes better healing, thus reducing recurrence.…”

“…Furthermore, glenohumeral IR causes effusion and hematoma to settle in the anterior glenohumeral joint, resulting in capsular distension and laxity. 7,12,16 Conversely, ER pushes the effusion and hematoma posteriorly, which allows the anterior structures to heal and tighten around the joint after dislocation. 7,12,16 Clinicians making recommendations about nonsurgical treatment options after initial shoulder dislocations should consider advocating immobilization in ER, especially if the patient is 21-30 years old.…”

“…7,12,16 Conversely, ER pushes the effusion and hematoma posteriorly, which allows the anterior structures to heal and tighten around the joint after dislocation. 7,12,16 Clinicians making recommendations about nonsurgical treatment options after initial shoulder dislocations should consider advocating immobilization in ER, especially if the patient is 21-30 years old. This is based on 2 studies 1,6 that demonstrated reduced recurrence rates and better functional and stability outcomes scores with immobilization in ER for patients in this age group, as well as the biomechanical and MRI literature.…”

Position of Immobilization After First-Time Traumatic Anterior Glenohumeral Dislocation: A Literature Review

“…After 3 weeks of immobilization, the Bankart lesion was still visible in less than 35% of the patients in the ER group compared to almost 80% of the patients immobilized in IR [31]. In a consecutive study, Siegler et al confirmed that ER has more effect on separation (100%) than displacement (22%) [32]. In this study, the positive influence on reduction of anterior hematoma in ER was also confirmed for 75% of the patients [32].…”