The abnormal mobility of the humeral head with respect to the scapula glenoid then explains the almost exclusively painful symptoms.
We can separate 2 different clinical situations :
painful post-traumatic instability
related to tearing and lack of proper healing of ligaments and / or labrum
painful instability with constitutional hyperlaxity of the shoulders
possibly decompensated by sometimes minor trauma, intensive or repetitive activity
The treatment is first medical and functional with muscle reinforcement of glenohumeral joint stabilizers.
In case of failure surgical stabilization may be considered with repair of labral lesions or capsuloplasty (‘capsular shift’) in the hyperlax shoulder and in the absence of identifiable lesions.