Update 

This article was updated on TK because of a previous error, which was discovered after the preliminary version of the article was posted online. In Table VII, the fracture rate in the study by Walch et al. that had read “4.6% (21 of 457)” now reads “0.9% (4 of 457).”

Background: 

Acromial and scapular fractures after reverse total shoulder arthroplasty (rTSA) are rare and challenging complications, and little information is available in the literature to identify patients who are at risk. This study analyzes risk factors for, and compares the outcomes of patients with and without, acromial and scapular fractures after rTSA with a medialized glenoid/lateralized humeral implant.

Methods: 

Four thousand one hundred and twenty-five shoulders in 3,995 patients were treated with primary rTSA with 1 design of reverse shoulder prosthesis by 23 orthopaedic surgeons. Sixty-one of the 4,125 shoulders had radiographically identified acromial and scapular fractures. Demographic characteristics, comorbidities, implant-related data, and clinical outcomes were compared between patients with and without fractures to identify risk factors. A multivariate logistic regression, 2-tailed unpaired t test, and chi-square test or Fisher exact test identified significant differences (p < 0.05).

Results: 

After a minimum duration of follow-up of 2 years, the rate of acromial and scapular fractures was 1.77%, with the fractures occurring at a mean (and standard deviation) of 17.7 ± 21.1 months after surgery. Ten patients had a Levy Type-1 fracture, 32 had a Type-2 fracture, 18 had a Type-3 fracture, and 1 fracture could not be classified. Patients with acromial and scapular fractures were more likely to be female (84.0% versus 64.5% [p = 0.004]; odds ratio [OR] = 2.75 [95% confidence interval (CI) = 1.45 to 5.78]), to have rheumatoid arthritis (9.8% versus 3.3% [p = 0.010]; OR = 3.14 [95% CI = 1.18 to 6.95]), to have rotator cuff tear arthropathy (54.1% versus 37.8% [p = 0.005]; OR = 2.07 [95% CI = 1.24 to 3.47]), and to have more baseplate screws (4.1 versus 3.8 screws [p = 0.017]; OR = 1.53 [95% CI = 1.08 to 2.17]) than those without fractures. No other implant-related differences were observed in the multivariate analysis. Patients with fractures had significantly worse outcomes than patients without fractures, and the difference in mean improvement between these 2 cohorts exceeded the minimum clinically important difference for the majority of measures.

Conclusions: 

Acromial and scapular fractures after rTSA are uncommon, and patients with these fractures have significantly worse clinical outcomes. Risk factors, including female sex, rheumatoid arthritis, cuff tear arthropathy, and usage of more baseplate screws were identified on multivariate logistic regression analysis. Consideration of these findings and patient-specific risk factors may help the orthopaedic surgeon (1) to better inform patients about this rare complication preoperatively and (2) to be more vigilant for this complication when evaluating patients postoperatively.

Level of Evidence: 

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

中文翻译：

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反向全肩关节置换术和肱骨外侧植入术的肩rom骨肩Total骨骨折：结局和危险因素分析

更新资料 

由于先前的错误，本文在TK上进行了更新，该错误是在将文章的初始版本在线发布后发现的。在表中，Walch等人在研究中的断裂率。原来读为“ 4.6％（457个中的21个）”的数据现在显示为“ 0.9％（457个中的4个）”。

背景： 

逆转全肩关节置换术（rTSA）后的肩and骨和肩cap骨骨折是罕见且具有挑战性的并发症，文献中几乎没有信息可用来确定有风险的患者。这项研究分析了内侧关节盂/外侧肱骨植入物在rTSA后发生肩峰和肩cap骨骨折的风险因素，并比较了有无肩patients骨和肩cap骨骨折的患者的预后。

方法： 

23名整形外科医师对3,995例患者中的1,425例肩部进行了原位rTSA治疗，其中1例设计为反向肩假体。在4125个肩膀中，有61个在影像学上确定了肩峰和肩cap骨骨折。比较有骨折和无骨折的患者的人口统计学特征，合并症，植入物相关数据和临床结果，以确定危险因素。多元逻辑回归，2尾不成对t检验，卡方检验或Fisher精确检验确定了显着差异（p <0.05）。

结果： 

经过至少2年的随访，肩部和肩cap骨骨折的发生率为1.77％，骨折发生在手术后的平均（和标准差）为17.7±21.1个月。10例Levy 1型骨折，32例2型骨折，18例3型骨折和1例无法分类。肩峰和肩cap骨骨折的患者更容易患风湿性关节炎（84.0％比64.5％[p = 0.004]；优势比[OR] = 2.75 [95％置信区间（CI）= 1.45至5.78]） （9.8％对3.3％[p = 0.010]； OR = 3.14 [95％CI = 1.18至6.95]），患有肩袖撕裂性关节炎（54.1％对37.8％[p = 0.005]； OR = 2.07 [95％ CI = 1.24到3.47]），并且要比没有破裂的螺钉多得多（4.1对3.8螺钉[p = 0.017]； OR = 1.53 [95％CI = 1.08至2.17]）。在多变量分析中未观察到其他与植入物相关的差异。与没有骨折的患者相比，具有骨折的患者的预后明显更差，并且这两个队列之间的平均改善差异超过了大多数措施的最小临床重要差异。

结论： 

rTSA后的肩rom骨和肩cap骨骨折很少见，患有这些骨折的患者的临床结局明显恶化。在多因素logistic回归分析中确定了包括女性，类风湿性关节炎，袖带撕裂性关节炎以及使用更多底板螺钉的危险因素。考虑这些发现和患者特定的危险因素可能有助于骨科医生（1）在术前更好地告知患者这种罕见并发症，以及（2）在对患者进行术后评估时更加警惕这种并发症。

证据级别： 

预后III级。有关证据水平的完整说明，请参见《作者说明》。