The relationship of bilateral shoulder arthroplasty timing and postoperative complications

Background: Though several case series have described bilateral shoulder arthroplasty results with range of motion, patient-reported outcomes, and complications, little guidance exists regarding the optimal interval timing between surgeries.

Methods: All patients from 2 insurance databases who underwent staged bilateral shoulder arthroplasty between 2005 and 2016 were identified. These patients were then stratified by elapsed time between surgeries into 4 study groups: (1) less than 3 months, (2) 3-6 months, (3) 6-9 months, and (4) 9-12 months. Surgical and perioperative medical complications of these patient cohorts were compared to a control group that underwent bilateral shoulder arthroplasty with a greater than 1-year interval between surgeries.

Results: From 2005-2016, a total of 1764 patients (6.3%) underwent bilateral shoulder arthroplasty out of 27,962 shoulder arthroplasties performed in the 2 databases. Of the bilateral patients, 49.1% waited more than 1 year before their second shoulder arthroplasty. Patients waiting less than 3 months between surgeries comprised 4.9% of the total number of staged bilateral surgeries. Demographics and comorbidities were similar between the study groups. Overall, implant complications were higher in patients with surgeries less than 3 months apart compared to controls, including revision arthroplasty (11.6% vs. 5.4%, odds ratio [OR] 2.29, P = .037), loosening/lysis (8.1% vs. 3.5%, OR 2.46, P = .032), and periprosthetic fracture (4.7% vs. 1.2%, OR 4.18, P = .010). There were no significant increases in any implant-related complications when surgeries were staged by 3 months or more compared to controls. Venous thromboembolism (VTE; 8.1% vs. 2.2%, OR 3.95, P = .001) and blood transfusion (9.3% vs. 1.7%, OR 5.82, P < .001) occurred at a significantly higher rate in patients with less than 3 months between surgeries compared with controls. There were no differences in any medical complications when surgeries were staged by 3 months or more compared with controls.

Conclusions: Patients with staged bilateral shoulder arthroplasty who have the second arthroplasty within 3 months have significantly higher rates of revision surgery, loosening/lysis, periprosthetic fracture, VTE, and blood transfusions. Based on these lower complication rates, surgeons should consider waiting a minimum of 3 months before performing the second portion of a staged bilateral shoulder arthroplasty.