Doran Michael, Boin Michael A, Anil Utkarsh, Bustamante Sebastian, Kwon Young W, Zuckerman Joseph D, Virk Mandeep S
Division of Shoulder and Elbow, Department of Orthopedic Surgery, New York University New York, NY, USA.
JSES Int. 2022 Nov 9;7(2):247-251. doi: 10.1016/j.jseint.2022.10.010. eCollection 2023 Mar.
Instability is one of the leading causes of revision for reverse total shoulder arthroplasty (RTSA). Closed reduction (CR) of a dislocated RTSA is recommended by many as initial treatment with varying degrees of success. In this study, we describe polyethylene liner dissociation from the humeral tray (PDH) as a cause of failure of CR of dislocated RTSA.
In this retrospective study, patients who underwent revision RTSA for instability were identified through our institutional database review using specific International Classification of Diseases and Current Procedural Terminology codes. Pertinent clinical information including demographics, details of instability event (early vs. late), traumatic vs. atraumatic, outcomes of CR (if performed), and intraoperative findings during revision surgery were collected and analyzed.
Twenty-two patients met the inclusion criteria with average follow-up of 2 years. CR was attempted in 12 (55%) patients, prior to revision surgery, and was successful in 5 (23%) patients. During the revision surgery polyethylene liner dissociation from the humeral tray (PDH) was identified in 10 patients (45%). Five of these 10 patients had failed CR and the other 5 patients did not undergo CR due to primary surgeon's preference. All patients with PDH event had onlay humeral tray RTSA system. Although not a consistent radiographic finding in our series, the presence of the metallic glenosphere in direct contact with the humeral tray on anteroposterior or axillary radiographs was diagnostic for PDH.
Dissociation of polyethylene liner from the humeral tray can be associated with an RTSA dislocation and is a contraindication for CR. A radiographic finding of the metallic humeral tray articulating directly with the glenosphere is an indication that the polyethylene liner is dissociated from the humeral tray.
不稳定是翻修反式全肩关节置换术（RTSA）的主要原因之一。许多人推荐对脱位的RTSA进行闭合复位（CR）作为初始治疗方法，且成功率各不相同。在本研究中，我们描述了聚乙烯衬垫与肱骨头托盘分离（PDH）是脱位的RTSA闭合复位失败的一个原因。
在这项回顾性研究中，通过我们机构的数据库审查，使用特定的国际疾病分类和当前手术操作术语代码，识别出因不稳定而接受翻修RTSA的患者。收集并分析相关临床信息，包括人口统计学资料、不稳定事件的细节（早期与晚期）、创伤性与非创伤性、CR的结果（如果进行了CR）以及翻修手术期间的术中发现。
22例患者符合纳入标准，平均随访2年。12例（55%）患者在翻修手术前尝试了CR，其中5例（23%）成功。在翻修手术中，10例（45%）患者被发现存在聚乙烯衬垫与肱骨头托盘分离（PDH）。这10例患者中有5例CR失败，另外5例患者由于主刀医生的偏好未进行CR。所有发生PDH事件的患者均使用了覆盖式肱骨头托盘RTSA系统。虽然在我们的系列研究中这不是一个一致的影像学表现，但在前后位或腋位X线片上金属球窝与肱骨头托盘直接接触可诊断为PDH。
聚乙烯衬垫与肱骨头托盘分离可能与RTSA脱位有关，是CR的禁忌证。金属肱骨头托盘与球窝直接相连的影像学表现提示聚乙烯衬垫已与肱骨头托盘分离。
