Biomechanics of posterior shoulder instability - current knowledge and literature review

Table 2 Different therapeutic options and considerations of posterior shoulder instability

Procedure	Consideration	Success rate
Conservative	Leads to loss of rotation and deformity of the shoulder, mainly performed in elderly patients	68%-77%, however only in isolated posterior shoulder instability; recurrence rate up to 96%[38,86]
Capsular-labral repair (i.e., post. - inf. capsular shift) or reverse Bankart repair	In isolated unidirectional posterior instability	96% in post. - inf. capsular shift[73] 91% in posterior capsulorrhaphy in isolated post. instability[5] Posterior Bankart repair – 93%[87]
Other procedures not/or rarely performed:
Thermal capsulorrhaphy	High recurrence rate	57%, capsular insufficiency 33%[88,89]
Posterior bone block or posterior wedge osteotomy	After failed capsular plication, or congenital formations	Posterior glenoid transfer: 53%; 41% complication rate[22,90] Posterior bone block: 45%; 36% osteoarthritis[36]
McLaughlin’s procedure	In patients with locked posterior shoulder dislocation from reverse Hill-Sachs lesions	improvement in average constant scoring system from 16 preoperatively to 72 postoperatively[91]
Humeral head allograft	Alternative option to McLauglin’s procedure	Complication rate between 25%-50%[92,93]