Polisetty Teja, Cannon Dylan, Grewal Gagan, Vakharia Rushabh, Levy Jonathan C
Department of Orthopaedic Surgery, Holy Cross Hospital, Fort Lauderdale, FL, USA.
Department of Orthopaedic Surgery, Holy Cross Hospital, Fort Lauderdale, FL, USA.
J Shoulder Elbow Surg. 2023 Jan;32(1):76-81. doi: 10.1016/j.jse.2022.06.020. Epub 2022 Aug 6.
Postoperative fracture of the acromion is a complication uniquely more common after reverse shoulder arthroplasty (RSA) than other forms of shoulder arthroplasty. There is limited knowledge regarding the etiology of these fractures or the anatomic risk factors. The purpose of this study is to identify associations of the acromioclavicular (AC) joint and relative humeral and glenoid positioning on the occurrence of acromial fractures after RSA.
A retrospective case-controlled study was performed on primary RSA patients treated by a single surgeon from September 2009 to September 2019. Patients with a postoperative acromion fracture were matched in a 3:1 ratio based on gender, indication, and age to those without a fracture and with a 2-year minimum follow-up. Preoperative and the immediate postoperative radiographs were reviewed by 2 investigators to measure critical shoulder angle, acromion-humeral interval, global lateralization, delta angle, preoperative glenoid height, and the level of inlay or onlay of the humeral stem. The morphology, width, and stigmata of osteoarthritis in the AC joint were assessed using computed tomography scans taken preoperatively.
Of a total of 920 RSAs performed, 47 (5.1%) patients suffered a postoperative acromion fracture. These patients were compared with a control group of 141 patients, with a mean age of 76.4 years and similar distributions of gender and surgical indication. Patients in both groups had similar preoperative glenoid height (P = .953) and postoperative degree of inset or offset of humeral implant relative to the anatomic neck (P = .413). There were no differences in critical shoulder angle, acromion-humeral interval, global lateralization, and delta angle both preoperatively and postoperatively between the fracture and nonfracture groups. Computed tomography analysis also showed no differences in AC joint morphology (P = .760), joint space (P = .124), and stigma of osteoarthritis (P = .161).
There was no relation between the features of the AC joint and the anatomic parameters of the humerus relative to the glenoid and acromion on postoperative acromion fractures after RSA.
肩峰术后骨折是一种独特的并发症，在反式肩关节置换术（RSA）后比其他形式的肩关节置换术更常见。关于这些骨折的病因或解剖学危险因素的了解有限。本研究的目的是确定肩锁（AC）关节以及肱骨和肩胛盂相对位置与RSA后肩峰骨折发生之间的关联。
对2009年9月至2019年9月由单一外科医生治疗的原发性RSA患者进行回顾性病例对照研究。术后发生肩峰骨折的患者根据性别、适应症和年龄以3:1的比例与未发生骨折且至少随访2年的患者进行匹配。两名研究人员对术前和术后即刻的X线片进行评估，以测量关键肩角、肩峰-肱骨间距、整体侧方移位、三角角、术前肩胛盂高度以及肱骨干的嵌入或覆盖水平。使用术前计算机断层扫描评估AC关节的形态、宽度和骨关节炎特征。
在总共进行的920例RSA手术中，47例（5.1%）患者发生了术后肩峰骨折。将这些患者与141例对照组患者进行比较，对照组患者的平均年龄为76.4岁，性别和手术适应症分布相似。两组患者术前肩胛盂高度相似（P = 0.953），术后肱骨头假体相对于解剖颈的嵌入或偏移程度相似（P = 0.413）。骨折组和非骨折组术前和术后的关键肩角、肩峰-肱骨间距、整体侧方移位和三角角均无差异。计算机断层扫描分析还显示AC关节形态（P = 0.760）、关节间隙（P = 0.124）和骨关节炎特征（P = 0.161）无差异。
RSA术后肩峰骨折与AC关节特征以及肱骨相对于肩胛盂和肩峰的解剖学参数之间没有关联。
