Glenohumeral joint dislocation is the most frequent joint dislocation with a prevalence of 1.7/100000 citizens/year. It is treated by reduction, under sedation or anaesthesia, followed by an immobilization of the arm.

The purpose of the study is to evaluate the healing of the labrum in first time anterior glenohumeral joint dislocation with a Bankart lesion in young patients by comparing an external rotation brace to an internal rotation brace to immobilize the injured arm.

Inclusion Criteria:

• > 18 years old
• < 40 years old
• anterior glenohumeral joint dislocation proved by radiography
• dislocation needing a reduction manoeuvre
• home close to evaluation site for 24 months follow-up visits
• signed consent form

Exclusion Criteria:

• associated fracture
• Hill-Sachs lesion = or > than 30%
• neurovascular deficit
• hypermobility
• pre-existing instability of the injured shoulder
• systemic neurological disease
• allergy to gadolinium
• functional sequel to the shoulder due to previous injury
• incapacitated adult patient
• minor patient
• home far from evaluation site
• refusal to sign the consent form