What Patients and Implants Are Most at Risk for Complications?

Which patient and implant variables are the biggest risk factors for complications and revisions after anatomic (aTSA) and reverse (rTSA) shoulder arthroplasty?

Every surgical procedure has risks, but by identifying the risk factors for patients that have previously experienced complications, we can potentially reduce the risk of complications going forward. Aibinder and colleagues analyzed an international database of over 8,500 patients (2,964 aTSA and 5,616 rTSA) to statistically analyze risk factors such as prior surgery, age or specific component sizes that increase the odds of complications and revisions after aTSA and rTSA.

• Revision risk by prosthesis type: aTSA patients had a significantly higher rate of complications (8.9% aTSA vs. 7.1% rTSA, p=0.0026) and revisions (5.7% aTSA vs. 2.4% rTSA, p<0.0001) compared to rTSA patients. However, no differences were observed in the intraoperative complication rate between aTSA and rTSA patients.
• Risk factors for revision: Younger age (<66yrs), more native glenoid retroversion (≥12°), Larger humeral stem size (≥12mm), greater humeral liner thickness, larger glenosphere diameter (>40mm), and more intraoperative blood loss (≥240mL) were risk factors for revision surgery after aTSA/rTSA.
• Implant/operative risk factors for revision: Larger humeral stem size (≥12mm), greater humeral liner thickness, larger glenosphere diameter (>40mm) and more intraoperative blood loss (≥240mL) were risk factors for revision surgery after aTSA/rTSA.

Preoperative identification of risk factors for complications and revisions can help surgeons better counsel their patients, set realistic expectations, and take extra precautions in the OR to help avoid occurrence.

These findings are limited because aTSA patients had a significantly longer follow-up time than rTSA patients, and these identified risk factors may not be generalizable given that all 8500+ shoulder prostheses were from the same implant design.