Goodloe J Brett, Denard Patrick J, Lederman Evan, Gobezie Reuben, Werner Brian C
Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA, USA.
Southern Oregon Orthopedics, Medford, OR, USA.
JSES Int. 2022 Aug 10;6(6):929-934. doi: 10.1016/j.jseint.2022.07.004. eCollection 2022 Nov.
Prosthetic instability is one of the most common short-term complications following reverse total shoulder arthroplasty (RTSA). Numerous strategies exist to attempt to mitigate this complication, including utilization of constrained polyethylene humeral liners. A concern of constrained humeral liners is that they may come at the expense of restricted rotational range of motion (ROM). The purpose of the present study is to compare range of ROM and patient-reported outcomes (PROs), and satisfaction among matched cohorts using constrained vs. unconstrained liners after RTSA.
A multicenter shoulder arthroplasty registry was retrospectively reviewed to identify patients with two-year clinical follow-up after RTSA with constrained liners used at the surgeon's discretion. All patients had the same inlay humeral prosthesis with a 135° neck shaft angle. This study cohort was matched 1:2 to control patients who underwent RTSA with standard liners based on age, sex, total glenoid-sided lateralization, glenosphere diameter, and surgery performed on the dominant arm. Improvement in PROs and ROM was compared between groups.
Twenty-two patients were identified who underwent RTSA with a constrained humeral liner; these were compared to 44 matched patients with standard liners. The groups were found to have no notable differences in demographics, baseline PROs and ROM. At two years postoperatively, both cohorts demonstrated improvements in all PROs without statistically significant differences between the two groups. There were no differences between groups in improvement in any ROM measure, including forward flexion (constrained: 54, standard: 57, = .771), external rotation at the side (constrained: 42°, standard: 41°, = .906) or internal rotation at 90 of abduction (constrained: 24, standard: 20, = .587).
For an inlay humeral prosthesis with a 135 neck shaft angle, utilization of a constrained liner for RTSA demonstrates no significant difference in ROM or PROs compared to a well-matched cohort of patients who underwent RTSA with a standard polyethylene humeral liner. These are reassuring data for using constrained liners when there is intraoperative concern for prosthetic instability.
假体不稳定是反式全肩关节置换术（RTSA）后最常见的短期并发症之一。存在多种策略试图减轻这种并发症，包括使用限制性聚乙烯肱骨头衬垫。限制性肱骨头衬垫的一个问题是它们可能以限制旋转活动范围（ROM）为代价。本研究的目的是比较RTSA后使用限制性衬垫与非限制性衬垫的匹配队列之间的ROM范围、患者报告结局（PROs）和满意度。
回顾性分析一个多中心肩关节置换登记处的数据，以确定在RTSA后接受两年临床随访且由外科医生酌情使用限制性衬垫的患者。所有患者均使用相同的内嵌式肱骨头假体，颈干角为135°。根据年龄、性别、全盂侧外移、关节盂球直径以及在优势臂上进行的手术，将该研究队列与接受标准衬垫RTSA的对照患者按1:2进行匹配。比较两组之间PROs和ROM的改善情况。
确定了22例接受带有限制性肱骨头衬垫的RTSA患者；将这些患者与44例匹配的使用标准衬垫的患者进行比较。发现两组在人口统计学、基线PROs和ROM方面无显著差异。术后两年，两个队列的所有PROs均有改善，两组之间无统计学显著差异。在任何ROM测量的改善方面，两组之间均无差异，包括前屈（限制性：54，标准：57，P = 0.771）、侧方外旋（限制性：42°，标准：41°，P = 0.906）或外展90°时的内旋（限制性：24，标准：20，P = 0.587）。
对于颈干角为135°的内嵌式肱骨头假体，与接受标准聚乙烯肱骨头衬垫的RTSA且匹配良好的队列相比，RTSA使用限制性衬垫在ROM或PROs方面无显著差异。当术中担心假体不稳定时，这些数据对于使用限制性衬垫是令人安心的。
