Background 

Lateralized reverse shoulder arthroplasty (RSA) has emerged as an attempt to improve on some of the drawbacks of conventional RSA, such as glenoid notching and decrease in ROM. Although this new design is being used in clinical practice, the evidence is mostly limited to case series and has not been systematically reviewed.

Questions/purposes 

(1) How much did patient-reported outcome measures (PROMs) and ROM improve among patients who receive a lateralized RSA implant? (2) What proportion of shoulders experience complications, revision surgery, or scapular notching?

Methods 

The PubMed and EMBASE databases were searched from database inception to January 31, 2020. We included clinical studies that reported the PROMs and/or ROM of patients with insufficient rotator cuffs undergoing RSA with a lateralized implant. All other types of studies and those including patients with fractures, instability or escape, infection, rheumatologic disease, neurologic disease, or revision surgeries as an indication for RSA were excluded. PROMs and ROM were collected and are reported as mean values and ranges. Complications, revision surgery, and scapular notching are presented as proportions. The percentage of the mean change relative to the minimum clinically important difference (MCID) was calculated using the anchor-based value for each outcome. The Methodological Index for Non-randomized Studies (MINORS) was used to assess study quality. The initial search yielded 678 studies; 61 full-text articles were analyzed according to our eligibility criteria. After a detailed analysis, we included nine studies that evaluated 1670 patients (68% of whom [1130] were women) with a mean age of 71.8 ± 0.6 years. The mean follow-up period was 41.1 ± 5.6 months. The mean MINORS score was 12 ± 4.

Results 

Active ROM improved for forward flexion (mean change 47° to 82°; MCID 12°), abduction (mean change 43° to 80°; MCID 7°), external rotation (mean change 8° to 39°; MCID 3°), and internal rotation (mean change -2 to 1 points). PROM scores also improved, including the American Shoulder and Elbow Surgeons score (mean change 20 to 50; MCID 20.9 points), Constant score (mean change 28 to 40; MCID 5.7 points), Simple Shoulder Test score (mean change 3 to 7; MCID 2.4 points), and VAS score (mean change -1.8 to -4.9; MCID -1.6 points). The proportion of shoulders with complications ranged from 0% (0 of 44) to 21% (30 of 140), and the proportion of shoulders with scapular notching ranged from 0% (0 of 76) to 29% (41 of 140). The proportion of patients undergoing revision ranged from 0% (0 of 44) to 13% (10 of 76) at short-term follow-up.

Conclusion 

Lateralized RSA is a reasonable alternative to medialized implants for patients with rotator cuff insufficiency because it might reduce the likelihood of scapular notching without apparently compromising PROMs or ROM. More studies are required to determine whether there is a direct correlation between the amount of lateralization and PROMs or ROM.

中文翻译：

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侧向反向肩关节置换术后临床结果的改善：系统评价

背景 

侧向反向肩关节置换术 (RSA) 的出现是为了改善传统 RSA 的一些缺点，例如关节盂切迹和 ROM 减少。尽管这种新设计正在临床实践中使用，但证据大多仅限于病例系列，并且尚未经过系统审查。

问题/目的 

(1) 在接受侧向 RSA 植入​​的患者中，患者报告的结果测量 (PROM) 和 ROM 改善了多少？(2) 有多少比例的肩膀出现并发症、翻修手术或肩胛骨切迹？

方法 

PubMed 和 EMBASE 数据库的检索时间为从数据库建立到 2020 年 1 月 31 日。我们纳入了一些临床研究，这些研究报告了接受侧向植入物 RSA 的肩袖不足患者的 PROM 和/或 ROM。所有其他类型的研究以及包括以骨折、不稳定或逃逸、感染、风湿病、神经系统疾病或翻修手术为 RSA 指征的患者的研究均被排除。收集 PROM 和 ROM 并报告为平均值和范围。并发症、翻修手术和肩胛骨切迹以比例形式呈现。使用每个结果的基于锚的值计算平均变化相对于最小临床重要差异 (MCID) 的百分比。非随机研究方法学指数（MINORS）用于评估研究质量。初步检索产生了 678 项研究；根据我们的资格标准对 61 篇全文文章进行了分析。经过详细分析，我们纳入了 9 项研究，评估了 1670 名患者（其中 68% [1130] 是女性），平均年龄为 71.8 ± 0.6 岁。平均随访时间为 41.1 ± 5.6 个月。平均未成年人分数为 12 ± 4。

结果 

前屈（平均变化 47° 至 82°；MCID 12°）、外展（平均变化 43° 至 80°；MCID 7°）、外旋（平均变化 8° 至 39°；MCID 3°）的主动活动度得到改善，和内旋（平均变化-2到1点）。PROM 评分也有所提高，包括美国肩肘外科医生评分（平均变化 20 至 50；MCID 20.9 分）、Constant 评分（平均变化 28 至 40；MCID 5.7 分）、简单肩部测试评分（平均变化 3 至 7；MCID 5.7 分） MCID 2.4 分）和 VAS 评分（平均变化 -1.8 至 -4.9；MCID -1.6 分）。发生并发症的肩部比例范围为 0%（44 人中的 0 人）至 21%（140 人中的 30 人），有肩胛切迹的肩部比例范围为 0%（76 人中的 0 人）至 29%（140 人中的 41 人）。在短期随访中，接受翻修的患者比例从 0%（44 例中的 0 例）到 13%（76 例中的 10 例）不等。

结论 

对于肩袖功能不全的患者来说，侧化 RSA 是内侧植入物的合理替代方案，因为它可以减少肩胛骨切迹的可能性，而不会明显损害 PROM 或 ROM。需要更多的研究来确定侧化量与 PROM 或 ROM 之间是否存在直接相关性。