Systematic Review and Meta‐Analysis of Locked Posterior Dislocation of the Shoulder Treated with Shoulder Arthroplasty: Improved Outcomes for Total Shoulder Arthroplasty are Associated with Increased Age

Abstract

Locked shoulder dislocations account for up to 5% of shoulder dislocations. These relatively rare injuries are characterized by dislocation of the humeral head from the scapular glenoid cavity with the humeral head incarcerated on the glenoid in a "locked" fashion. Diagnosis is often delayed because of the complexity of clinical presentation and subtle radiographic findings, resulting in locking of the humeral head out of the glenoid cavity with severe functional deficits. Most commonly, there are bony injuries to the glenoid and humeral head that engage and prevent closed reduction. Since few patients present with this injury, evidence-based treatment guidelines have not been established. The objective of this review is to assess postoperative outcomes following shoulder arthroplasty for locked posterior shoulder dislocations (LPSD) to guide best practices for treatment. This systematic review was conducted following PRISMA guidelines, searching the PubMed and Web of Science databases for original articles assessing outcomes following arthroplasty for locked posterior shoulder dislocations. Seven publications that evaluated 102 patients were included. Additionally, nine case studies were included, assessing 20 shoulder arthroplasties. Overall, the analysis demonstrated significant improvement in shoulder pain following total shoulder arthroplasty (TSA) (P = 0.0003). Older operative patient ages for TSA resulted in significantly improved modified Neer outcomes scores and patient satisfaction compared to younger patients (P = 0.047). A positive correlation was noted for the duration of dislocation and necessity for revision surgery following hemiarthroplasty (HSA) and TSA combined and TSA separately. The risk ratios assessing the incidence of postoperative complications (RR = 0.56, 95% CI = 0.28-1.11) and necessity for revision surgery (RR = 0.58, 95% CI = 0.24-1.39) were insignificant but noted outcomes favoring TSA. Data from the included studies show that both TSA and HSA are efficacious at treating locked posterior shoulder dislocation. Postoperative outcomes following TSA versus HSA are similar. TSA may be a more efficacious surgical treatment in elderly patients, with improved outcomes and patient satisfaction scores compared to younger patients. Early diagnosis and treatment of posterior locked dislocations may lead to reduced postoperative complications and revision surgery, signaling the importance of proper injury investigation and early treatment. The role of RSA in the management of locked posterior shoulder dislocation remains to be determined, as there is insufficient clinical outcome data currently in the literature.

A Case of Neglected Posterior Fracture Dislocation of the Shoulder Treated With Greater Tuberosity Osteotomy

“…Treatment options vary for posterior shoulder dislocations depending on the duration of dislocation, the size of the humeral head defect, the severity of the glenoid bony injury, the integrity of the rotator cuff, and the patient's functional demand [ 3 , 14 ]. With more severe clinical presentations where dislocation is accompanied with extensive damage to the bony structures, cartilage, or ligaments, or with osteoarthritis, shoulder arthroplasty is preferred to reduce the dislocation and optimize long-term shoulder stability and function in older adult patients [ 16 – 18 ]. In contrast, if the degree of instability in the shoulder joint is not severe without bone loss of the humeral head and glenoid fossa, preservation of the shoulder joint should be considered in young active patients.…”

“…Posterior fracture dislocations show a locked fashion as they are accompanied with simultaneous fractures of the humerus or scapula [ 19 – 21 ]. Bony injuries to the glenoid and humeral head can lock into place, thereby preventing closed reduction [ 18 ]. Open reduction and internal fixation should be considered even for chronic conditions if there is no deficiency in terms of rotator cuff integrity.…”

From Diagnosis to Decision-Making: A Systematic Review of the Management of Reverse Hill-Sachs Lesions after Posterior Shoulder Dislocations

“…Furthermore, in elderly patients, partial or total shoulder replacement may be the most effective option [9][10][11].…”